Category: Water

A generational historic struggle to regain our water

A generational historic struggle to regain our water

By Sharon Udasin

May 14, 2021 — Editor’s note: This story is part of a collaboration, Tapped Out: Power, justice and water in the West, in which eight Institute for Nonprofit News newsrooms — California Health Report and High Country News; SJV Water and the Center for Collaborative Investigative Journalism; Circle of Blue; Columbia Insight; Ensia; and New Mexico In Depth — spent more than three months reporting on water issues in the Western U.S. The result documents serious concerns including contamination, excessive groundwater pumping and environmental inequity — as well as solutions to the problems. It was made possible by a grant from The Water Desk, with support from Ensia and INN’s Amplify News Project.

A riverbed that has been parched since the end of the 19th century — a portion of the historic lifeblood of the Gila River Indian Community — is now coursing again with water, luring things like cattails and birds back to its shores.

“You add water and stuff just immediately starts coming back naturally. Birds have returned and it’s just such a different experience,” says Jason Hauter, an attorney and a Community member. “It’s amazing how much has returned.”

INN Tapped Out logo in white

The revival of this small segment of the 649-mile (1045-kilometer) Gila River, which has served the tribes that make up the Gila River Indian Community — the Akimel O’odham (Pima) and the Pee-Posh (Maricopa) — for roughly 2,000 years, was an added benefit of a grassroots infrastructure overhaul, known as “managed aquifer recharge,” or MAR, which aimed to restore the local groundwater basin. The MAR project has not only secured a water supply for local agriculture, but it has also generated a stable source of income and strengthened the Community’s ties to tradition.

“The land started to heal itself, reinvigorate itself,” says Governor Stephen Roe Lewis, who recently began his third term as leader of the Gila River Indian Community.

Hauter credits Lewis and his colleagues for ensuring that Community members have long-term access to their own resources while helping solve broader water supply problems in the region through innovative partnerships and exchanges with neighbors.

“They are very thoughtful about future generations, but they also recognize they live in this larger community and that you have to collaborate,” Hauter says. “Encouraging your neighbors to have good water practices, but also helping your neighbors, is good water policy.”

A Particularly Longstanding Claim to Water Rights

The ins and outs of water management and usage in the U.S. West are complex. In a region where every drop is important, questions about water — such as who gets what, how it’s moved from one place to another, and who pays for it — are vital to communities’ capacity to survive and thrive. These decisions are often based on century-plus-old legal doctrines that don’t always fit neatly into a modern, warming world — or address longstanding disregard for Native American tribal nations’ rights.

Western U.S. states adhere to legal doctrines called “prior appropriation” — sometimes referred to as “first in time, first in right” — linked to the mid-19th century Gold Rush and the Homestead Act, through which miners and farmers were able to claim and divert water sources for “beneficial use” — defined by activities such as irrigation, industry, power production and domestic use. A 1908 Supreme Court case ruled that the federal decision to establish Native American reservations inherently meant there would be sufficient water for those reservations. The priority date for water rights on these reservations therefore had to match the date of establishment, meaning that many tribal nations’ water rights took precedence over those of most existing users. During the past few decades, these nations have largely opted for settlements with the relevant federal, state and private bodies, rather than entering extensive and costly litigation to recover their water rights. 

These settlements allow tribal nations to take part in the competitive markets that have long ruled water in the West. These markets involve things like selling water rights, getting money for helping mitigate drought and accruing “credit” from the Arizona Water Banking Authority by storing water in underground basins administered by the Arizona Department of Water Resources. 

Governor Stephen Roe Lewis, leader of the Gila River Indian Community, stands in the dry bed of the Gila River, outside of Sacaton, Arizona. Photo © J. Carl Ganter / Circle of Blue
Governor Stephen Roe Lewis, leader of the Gila River Indian Community, stands in the dry bed of the Gila River, outside of Sacaton, Arizona. Photo © J. Carl Ganter / Circle of Blue

One such pivotal settlement came in 2004: To resolve tribal water rights claims, Congress passed the Arizona Water Settlement Act, which allocates a set amount of water each year to the Gila River Indian Community, drawing that water budget from a variety of sources in Arizona. The Community had a particularly longstanding claim to water rights due to its two-millennia history of farming, curtailed when miners and white settlers began diverting water following the Civil War. The governor’s late father, Rodney Lewis, devoted his career as Gila River Tribal Attorney to fighting for a just water settlement.

“It was the theft of our water, so this was a generational historic struggle to regain our water,” Lewis says. “We were and we still are historically agriculturalists, farmers. Our lineage, our ancestors were the Huhugam. And the Huhugam civilization had pretty much cultivated the modern-day Phoenix area in central Arizona.”

“They were master builders,” he adds, referring to complex water systems and canals that he says rivaled those of the Nile Valley.

As more and more nations regain control of their water resources, they are securing a critical provision for the long-term financial prosperity of their people and protection of their lands.

Mutually Beneficial Partnerships

As often occurs in tribal water rights settlements, the 2004 agreement served to restore the Gila River Indian Community’s claims to the river and its tributaries without displacing the descendants “of those who committed the original sin,” says Hauter, a partner at the law firm Akin Gump Strauss Hauer & Feld, which currently serves as outside counsel for the Community.

Toward that end, Hauter says, “really, what’s provided is an alternative supply.”

That alternative supply comes from the Central Arizona Project (CAP), an infrastructural behemoth that conveys about 1.5 million acre-feet (1.85 billion cubic meters; one acre-foot is about 326,000 gallons) of water from the Colorado River to central and southern Arizona each year. Serving as the single largest renewable water supply for the state of Arizona, the 336-mile (540-kilometer) system was authorized by then-President Lyndon B. Johnson in 1968, soon after which construction by the Bureau of Reclamation began. Three years later, the Central Arizona Water Conservation District ­— a multi-county water district — formed to repay the federal government for the project’s costs and oversee regional water supply.

The Central Arizona Project / Circle of Blue photo
The Central Arizona Project canal moves water from the Colorado River to interior Arizona. Photo © J. Carl Ganter / Circle of Blue

Through the 2004 settlement, the Gila River Indian Community has the single largest CAP entitlement — bigger than that of the city of Phoenix — at 311,800 acre-feet (385 million cubic meters), Hauter explains. Finding mutual benefit in helping quench the thirst of the surrounding region, the Community entered into various water exchanges and leases that delivered about 60,000 acre-feet (74 million cubic meters) to Phoenix and other municipalities annually and left about 250,000-acre-feet (308 million cubic meters) for its own purposes, according to Hauter.

But this sudden surplus from the CAP actually posed a problem.

Pumping water from the project, Community members understood, would eventually become prohibitive due to water transport and associated electricity costs. The Lower Colorado River Basin Development Fund, managed by the U.S. Department of Interior, covers the Fixed OM&R (operation, maintenance and replacement) for certain Arizona tribes with settlements, but funding is only projected to last until 2045, Hauter explains.

The Community was using only about 50,000 acre-feet (62 million cubic meters) for irrigation purposes, leaving about 200,000-acre-feet (247 million cubic meters) unused, Hauter says. Because any unused CAP water can be remarketed by the state, Arizonans began counting on the Community to not use its full share.  

With the legal guidance of Hauter and his team, the Community launched a strategic venture to store, share and sell much more of its CAP water in 2010.

The first such partnership occurred with former water supply rival the Salt River Project, the name of the utilities responsible for providing most of Phoenix’s water and power. Had the Community decided to enter litigation to recover its water rights, rather than settling, the Salt River Project could have faced enormous supply losses.

But the former rivals instead became partners, after identifying that the Salt River Project’s underground storage facility (USF), the Granite Reef Underground Storage Project, was an ideal place to store a portion of the CAP allocation the Gila River Indian Community was not currently using. The partnership has enabled the Salt River Project to withdraw water from storage — while maintaining a “safe yield,” or making sure any water that is taken from aquifers is replenished. In return, the Community has gained long-term storage credit, Hauter explains. Such storage credit enables the holder to bank CAP water and, when necessary, recover the water for future use.

The Community also stores water in groundwater savings facilities (GSF), including one operated by the Salt River Project and another south of the Gila River operated by the Maricopa Stanfield Drainage District. While a USF physically stores water in the aquifer through direct recharge, a GSF is an “indirect” recharge facility that uses CAP water instead of pumping local groundwater.

In what Hauter described as an “in lieu” agreement, the Community provides the operators of these GSF facilities with a renewable water supply — another portion of its CAP allocation — and so reduces the Salt River Project and Maricopa District’s need to extract groundwater. In return, the Community gets storage credit for the water that can remain in the ground.

“Everything We Needed Was at the River”

While these external collaborations bolstered the resilience of the Community, as well as that of the arid surrounding region, Gila River residents only really saw the revival of their long-lost local waterway when Community leaders launched a homegrown storage initiative. Recognizing the value in keeping some unused CAP resources at home, they chose to establish a network of managed aquifer recharge (MAR) sites. This type of underground storage allows for the free flow of water from a naturally permeable area, such as a streambed, into an aquifer, as opposed to “constructed recharge” sites that involve injecting water into percolation basins by means of a constructed device.

Image of local water cycle and groundwater basics

Creating a balance of water that’s taken from aquifers and water that replenishes aquifers is an important aspect of making sure water will be available when it‘s needed. Image from ”Getting down to facts: A Visual Guide to Water in the Pinal Active Management Area“, courtesy of Ashley Hullinger and the University of Arizona Water Resources Research Center.

In order to implement these plans, the Gila River Indian Community came to an agreement with Arizona to acquire state regulatory permits for the MAR projects, despite the fact that tribal nations have sovereign control over water management. As a result of this decision, the Community has been able to market long-term storage credits in a sort of environmentally friendly banking system that allows more groundwater to stay in the ground.

“They realized they could get multiple benefits from deciding to have their project permitted per the Arizona regulations,” says Sharon Megdal, director of The University of Arizona Water Resources Research Center. 

“They voluntarily chose to abide by the regulations for storage and recovery and therefore come under the whole credit accrual and accounting system,” she continues, stressing that not only can credits be used to recover water when needed in the future, but they can also be purchased by outside entities, which creates a revenue stream for the Community. “That’s really exciting.”

Managed Aquifer Recharge site #5 (MAR 5)
“You add water and stuff just immediately starts coming back naturally. … It’s amazing how much has returned,” says Jason Hauter. The “managed aquifer recharge,” or MAR, projects have allowed the Gila River Indian Community to achieve river and riparian restoration. Image courtesy of the Gila River Indian News

Three MAR facilities are already operating on the reservation today: MAR-5, the Olberg Dam underground storage facility, permitted in 2018; MAR-1B, the Cholla Mountain underground storage facility, permitted in 2020; and MAR-6B, a western and downstream expansion of MAR-5, which came online a few months ago. Construction of MAR-8, located downstream from MAR-5, will be complete in a few years, according to Hauter.

Hauter adds that it was only while planning the initial MAR-5 site that Community members envisioned the riparian restoration program that served “to recreate the river,” allowing cattails and other plants to blossom and enabling community members to create baskets and traditional medicines. Although the idea of restoring the river was secondary to the storage plans, Hauter says that its flow is intrinsic to the Community’s culture.

“The tangible benefit for most members is really having the river back to some degree,” Hauter adds. “It wasn’t something the settlement intended to accomplish, but the settlement gave the Community the tools to make it happen.”

Lewis and his father, who had already retired at the time, used those tools to see the first MAR site to fruition. The Lewises and their colleagues understood the benefit in adopting innovative methods for accumulating water at their future storage site.

Following the death of water rights attorney Rodney Lewis, his widow Willardene Lewis — a child welfare attorney and a writer, as well as the governor’s mother — published a poem about death and the Gila River. Click to expand. Image courtesy of the Gila River Indian News

“He truly saw the MAR-5 as a living testament to our historic tie to the Gila River,” the governor says, adding that his father considered the facility an opportunity to “return the flow of the river.”

With the revived river flow, the riparian habitat quickly began blossoming, including 50 documented species of birds within the first year of MAR-5’s operations, Lewis says. An interpretive trail now weaves through the once arid wetland, providing educational signposts and offering sacred cultural spaces for spiritual practice, Lewis explains. Elders are now taking advantage of the plants and silt available to engage in traditional basket weaving, medicine making and pottery, he adds.

“They still remember the river sometimes flowing and the smell of the water,” Lewis says.

In recent years, before the opening of the MAR-5 site, the channel filled with water only in particularly wet seasons involving floods or heavy snowpack upstream, according to Lewis.

“Everything we needed was at the river,” he adds. “That was our lifeblood.”

Continuing to Plan For a Drought-Ridden Future

In conjunction with the opening of the MAR facilities, the Community cemented a pivotal agreement in 2019 with the Central Arizona Groundwater Replenishment District (CAGRD), a groundwater replenishment entity operated by the Central Arizona Water Conservation District. Through this agreement, CAGRD leases 18,185 acre-feet (22 million cubic meters) of the Community’s CAP water and stores the majority of that water in the MAR sites, while receiving long-term storage credits in return from the Arizona Water Banking Authority. Only if the MAR facilities are full is CAGRD allowed to store the leased water elsewhere, Hauter explains.

Alongside the MAR projects, the Community has also been rehabilitating existing wells and building new ones in order to create a backup supply for agricultural use when Gila River flow is minimal. Well water is less expensive than CAP water, since wells can recharge naturally during storms — so much so that such events collectively add at least 100,000 acre-feet (123 million cubic meters) to the Community’s annual water supply, according to Hauter. The Community took additional steps to reroute its CAP supplies after the federal government and the seven Colorado River Basin States implemented their drought contingency plans, meant to elevate water levels in Lake Mead, in 2020. As part of that regional effort, Hauter explains, the Community is providing a total of at least 200,000 acre-feet (247 million cubic meters) of water to be stored in Lake Mead from 2020 to 2026, when the drought contingency plans expire. For its contribution, the Community gets money through the Arizona Water Bank and the Bureau of Reclamation.

Lake Mead water levels from 2000 to 2015
This animation shows a comparison of Lake Mead water levels from 2000 to 2015. The Gila River Indian Community is taking part in efforts to elevate water levels in the lake by contributing portions of its Central Arizona Project entitlement. Images by Joshua Stevens, using Landsat data from the U.S. Geological Survey, courtesy of NASA Earth Observatory (public domain)

Only through the Community’s creative collaborations and homegrown projects has so much of its CAP entitlement been able to help replenish Lake Mead, Hauter says. Today, the Community has reduced its CAP water usage for irrigation to 15,000 acre-feet (19 million cubic meters) per year, while its CAP water storage capacity in the MAR projects is up to about 40,000 acre-feet (49 million cubic meters) per year. After construction of MAR-8 is complete, total CAP water use for storage and irrigation will reach about 75,000 acre-feet (93 million cubic meters), Hauter says.

As the Community’s leaders continue to plan for a drought-ridden future, they are evaluating whether it will be necessary to use more of its CAP allocation for their own needs. At the moment, much of the reservation’s agriculture involves water-intensive crops like alfalfa, feed corn and cotton. An overhaul of the farming infrastructure, according to Hauter, would require “changing attitudes about how food is grown” and incorporating more efficient technologies, as well as encouraging farming among younger people.

Overall, Hauter says, “it’s an exciting future for the Community, and it will be interesting to see what happens in the next 20 or so years.”

Lewis is confident that the Community’s agricultural tradition will remain strong, particularly due to the younger generation’s concerns for social justice, equity and environmental issues.

“We want to provide opportunities for our community members to reengage in any way in our agricultural heritage,” he says. “We’ve always been innovators, going back to the Huhugam with their amazing engineering.”

In addition to the commercial company Gila River Farms, which is owned by the tribe and employs Community members, Lewis says that local family farms continue to thrive. Lewis also says that “there’s a big push” for young people to obtain degrees in agro-business, hydrology, water engineering and other relevant fields that will provide them with a livelihood while working for their Community — a place that has become even more special to them during the pandemic year.

“It’s a public health emergency that we’ve been going through,” Lewis adds. “But at the same time, I think this is an opportunity where you see a lot [of] our younger generation that are wanting to learn who it is to be from the Gila River Indian Community.”

“A Total Win-Win”

While the MAR projects and the larger water exchange deals serve to safeguard the Community’s water supplies, Hauter says he’s uncertain as to whether neighboring tribal nations could replicate this model. Other tribes, he explains, might have different agricultural interests or economic concerns, as well as varying geological and hydrological conditions.

In Megdal’s opinion, at least one aspect of the Community’s strategy could be replicable regardless of geography: the strategic accrual and marketing of long-term storage credits in permitted recharge facilities. The Gila River Indian Community has diversified its portfolio of storage credit and sales through “multiple vehicles,” she explains, including its MAR projects, the Salt River Project partnership, and its transfer of credits to CAGRD. 

“They are able to meet their objectives including having riparian benefits and river benefits and sell the credits — because the credits are then recovered elsewhere. … For them, it’s like a total win-win,” Megdal says, adding that she considers the Community’s achievements to be “a bellwether project.”

Already, she says, the Tucson-region Tohono O’odham Nation has begun selling some credits to CAGRD. Acknowledging that the two cases involve varying geological and legislative circumstances, Megdal stresses that the Gila River Indian Community has demonstrated the benefits of the storage and credit accrual system.

“These long-term storage credits are the most marketable part of the water system,” Megdal says. “It’s an emerging market, and the Gila River Indian Community has emerged as a key leader in that market.”

“I see this example of a tribal nation entering voluntarily into an intergovernmental agreement with the state so that all the parties can develop these mutually beneficial exchanges or marketing transactions in a voluntary way,” she adds. “It’s really a notable innovation.”

Editor’s note: This story is also part of a four-part series — “Hotter, Drier, Smarter: Managing Western Water in a Changing Climate” — about innovative approaches to water management in the U.S. West and Western tribal nations. The series is supported by a grant from the Water Desk at the University of Colorado Boulder and is included in our nearly year-long reporting project, “Troubled Waters,” which is supported by funding from the Park Foundation and Water Foundation. You can find the other stories in the series, along with more drinking water reporting, here.  

Cover photo by Gila River India News.
Heating of the Tasman sea warms up the climate of Antarctic Peninsula via changes in wind patterns, suggests new study

Heating of the Tasman sea warms up the climate of Antarctic Peninsula via changes in wind patterns, suggests new study

Heating of the Tasman sea warms up the climate of Antarctic Peninsula via changes in wind patterns, new study by Japanese and Australian scientists shows

The Antarctic Peninsula is melting faster than ever. In a recent study, scientists have revealed how heating in the Tasman sea causes warming of the West Antarctic region and leads to melting of ice and rise in sea levels. They suggest that wind streams flowing towards poles from the tropics play an important role in these oceanic and temperature variations. These findings can be helpful to populations that are vulnerable to sea level rise.

The melting of the Earth’s ice cover intensified in the 20th century, with glaciers and sea ice in the Arctic and Antarctic regions melting at alarming speeds. In fact, The Antarctic Peninsula (AP), which is the only landmass of Antarctica extending out past the Antarctic Circle, was found to be one of the most rapidly warming regions on the planet during the second half of the 20th century. This rapid change in climate has raised serious concerns of rising sea levels the world over.

Multiple factors have been associated with the melting of the ice cover: the primary factor being the greenhouse gas emissions from human activities that cause warming up of the atmosphere and the oceans and the consequent ice melting. Apart from this, atmospheric variations, ocean currents, and wind patterns also play a significant role. Now, a collaborative group of scientists from Japan and Australia—led by Assistant Professor Kazutoshi Sato from Kitami Institute of Technology and Associate Professor Jun Inoue from the National Institute of Polar Research in Japan—has focused efforts on understanding how fluctuations in these climatic factors affect the warming of the Antarctic. They have documented their findings in a brand-new article published in Nature Communications.

Previous studies have examined the relationship between the wind dynamics over the Southern Ocean (also called SO; located north of Antarctica) and climate variability in tropical oceans. It was found that heating in tropical regions generates atmospheric waves called “Rossby wave trains” from the tropics to the Antarctic region via the SO, which causes heating of the West Antarctic region. Interestingly, Rossby waves are an attempt of nature to balance heat in the atmosphere as they transfer heat from the tropics to the poles and cold air towards the tropics.

On the path of understanding the warming of AP, Dr. Sato points out, “The impacts of climate variabilities over the mid-latitudes of the Southern Hemisphere on this Antarctic warming have yet to be quantified”. His team addressed this gap by looking at the climate changes in the Tasman Sea located between Australia and New Zealand and the SO and drew correlations with temperature variations in the AP.

Dr. Sato and his team analyzed the temperature data from six stations in AP and the wind and cyclone patterns over the Tasman sea and the SO from 1979 to 2019. They found that even without unusual heating in the tropics, only the heating in the Tasman Sea modifies the wind patterns over the SO and forces the Rossby waves to move even deeper into the Amundsen sea low, a low-pressure area lying to the west of the AP. This larger pressure gradient causes stronger colder winds towards the poles. The meandering wind stream moves towards the AP, resulting in the warming of this region. Additionally, this effect was found to be prominent in the winter months when the cyclones are more active. “We have shown that warm winter episodes in the Tasman Sea influence warm temperature anomalies over key regions of West Antarctica, including the AP, through a poleward shift of South Pacific cyclone tracks”, Dr. Sato summarizes.

The ever-increasing warming of the AP—rather, the whole of Antarctica at large—is a major concern plaguing climatologists all over the world. Commenting on the serious implications of this rapid rise in temperature and sea levels and the importance of the findings of their study, Dr. Inoue says, “Antarctic warming accelerates Antarctic ice sheet melting and contributes to the rise in sea levels across the world. Therefore, knowledge of the mechanisms of the melting of the Antarctic ice sheet would help scientists, policymakers, and administrations to devise measures for people who will be most affected by the rising sea levels.”

Dr. Sato and his team conclude by stating that the findings of their study can also aid the future forecast of ice sheet melting in Antarctica and the consequent global sea level rise.

Read the original story here.
Cover photo by Phillip Capper / Wikimedia Commons.
Podcast: Climate change is flooding the Arctic Ocean with light – what it means for the species that live there

Podcast: Climate change is flooding the Arctic Ocean with light – what it means for the species that live there

By Daniel Merino and Gemma Ware

This is a transcript of episode 5 of The Conversation Weekly podcast, How climate change if flooding the Arctic Ocean with light. In this episode, two experts explain how melting ice in the far north is bringing more light to the Arctic Ocean and what this means for the species that live there. And we hear from a team of archaeologists on their new research in Tanzania’s Olduvai Gorge that found evidence of just how adaptable early humans were to the changing environment.

NOTE: Transcripts may contain errors. Please check the corresponding audio before quoting in print.

Dan Merino: Hello and welcome back. From The Conversation, I’m Dan Merino in San Francisco.

Gemma Ware: And I’m Gemma Ware in London and you’re listening to The Conversation Weekly, the world explained by experts.

Dan: In this episode, two Arctic Ocean researchers explain how melting ice in the far north leads to more light in the Arctic – and what that means for sea life.

Karen Filbee-Dexter: Our ecosystems are responding, because these changes are really dramatic and they’re noticeable.

Gemma: And we talk to a team of archaeologists about the early humans who lived in Tanzania’s Olduvai Gorge 2 million years ago.

Makarius Peter Itambu: In this scenario, hominims from Oldupa maintained the very same toolkit.

Dan: So Gemma, today we’re going on a journey up to just about as far north as we can go, all the way up to the Arctic. What do you imagine when I say the word Arctic?

Gemma: I feel a bit cold already, and I guess I think of big expanses of snow and ice, drifting, like wind. Maybe the odd polar bear. And I guess in winter it’s just dark.

Dan: That’s a great example if you were to stay on top of the ice, but there’s a whole different world beneath it. And it’s full of ocean, like teeming alive.

Gemma: We know climate change is causing some of this ice to melt though, right?

Dan: Yeah totally… well some of the ice melts every summer. The sun’s up and then in winter when the sun goes away it grows back, but that ice is melting much more than it used to. So in September 2020, Arctic sea ice covered 3.74 million square kilometres.

Gemma: Well that sounds like a lot…

Dan: It does. But it’s the second smallest measurement ever. And only roughly half of what was measured in 1980.

Gemma: So what does that melting sea ice mean for all that teeming sea life living in the Arctic Ocean?

Dan: It’s not clear cut… it’s not all bad news even. Different scientists are studying all sorts of changes to see how it’s going to matter for the life in the Arctic, but one of the things they’re looking at is light. If there’s less and less sea ice, more light gets down into the ocean. And in the dark winter, where ice would normally cover the ice caps, it’s not there, so ships are driving through more and more and bringing with them a lot of artificial light.

I spoke to two researchers who’ve been spending a lot of time in the cold icy waters way up north to study all of this. And let’s just let one of them kind of set the scene. So Gemma, and all you listeners out there, imagine you step off a plane in the far, far north. Here’s what you might see.

Karen: So you have these places that are so covered in snow and ice, that they almost have a moon landscape of just bare rock in the summer. No leaves, no forest, no trees.

Dan: That’s Karen Filbee-Dexter, a research fellow at the university of Western Australia and a scientist at the Institute of Marine Research in Norway. She’s talking about the shoreline there. The long dark winters make it so that even in the sunny summer, the landscape is barren. But in the ocean, there’s a very a different story.

Karen: And then you go under water and you have to go a little bit deeper, but when you dive you sort of past this zone, where all of a sudden these amazing underwater forests appear.

Dan: These forests are not made of trees of course, but of kelp, attached to the sea floor, swaying in the currents.

Karen: So you have these long blades that will float in the water column and then they, just like a forest, shade light and create these understory conditions that fish and animals use and live in the same way as a forest does on land.

Dan: And how big are we talking? And I’m thinking Redwood trees, or am I thinking a bush in my yard kind of size?

Karen: It depends on the species and it depends on the forest. So, the first kelp forest that I dove on in the Arctic was about one to two meters tall. And it was actually in Arctic Norway. But the largest kelp forest that I’ve been in the Arctic has been in Canada. So there is an area in Nunavut where the kelp was about three to five meters tall. And that was spectacular.

Dan: Until recently, not too much was known about Arctic kelp. What kind grow where, or even how much there is.

Karen and her colleagues at the Arctic Kelp project, an aptly named group of universities, institutions and NGOs across Canada, are trying to catalogue which kelps are growing in the Arctic today, and how the warming temperatures are going to affect where they grow in the future.

Karen has spent a lot of time underwater using scuba gear to study these kelp ecosystems. But for many of these places, you can only access them in the short window when sea ice disappears.

Karen: So that’s what’s incredible about these habitats. They’re covered by ice. For sometimes more than half of the year and they require light to live. So they’re just growing based on light that reaches the sea floor in this very short period when the ice is not there.

A scuba diver swims through kelp fronds.
A diver explores a four-metre-high sugar kelp forest off Southampton Island, Canada. Ignacio Garrido/ArcticKelp, Author provided

Dan: Kelps, and well, everything in the Arctic Ocean, spend a huge amount of time in the dark, either because it’s winter the sun hasn’t come up for months, or because the sea surface is covered by ice. When the ice melts and daylight returns, kelps grow really fast. They have to, it’s a short growing season. But that growing season is getting longer.

Karen: What’s happening now in the Arctic is we have this massive and dramatic loss of sea ice. So this means that a large amount of Arctic coastline, which is normally covered in ice and normally doesn’t get that much light is now suddenly sort of open to, to the sun.

Dan: All you gardeners out there will know this equation: more sunlight, more growth. As Arctic temperatures warm due to climate change and sea shrinks, these underwater forests are expanding, and kelp is now growing in places where it didn’t used to.

Karen: So based on, how the conditions have changed from 1950 to now, we can predict that the migration rate in the Arctic is about, 20km per decade. So this sort of poleward expansion is definitely marching along, and there’s all the evidence that these changes are accelerating.

Daniel: 20km per decade is pretty fast for a bunch of trees

Karen: Yes, the marching forest. It is definitely something out of a Lord of the Rings movie. But the rules are different in the Arctic, right? So, so it’s changing much faster than the rest of the world. Everything happening there is happening at, you know, two to three times the rate of change. So, we’re already way into the climate change future, along our Arctic coastlines. So it’s not surprising that our ecosystems are responding because these changes are really dramatic and they’re noticeable. And they’re going to put a lot of pressure on marine species to move.

Dan: These changes which are causing kelp to expand and move are not good everywhere though. A lot of the Arctic coastline is made of permafrost.

Karen: This is essentially frozen soil. When that frozen soil thaws all of that dirt and sediment just flushes into the coastal zone and creates a lot of turbidity.

Dan: This murky brown water prevents light from reaching the seafloor and the kelps growing there.

Another side effect of climate change is that glaciers and ice sheets are melting and dumping huge amounts of fresh water into coastal areas, that can also harm kelp.

So while not every change is good for kelps and seaweeds way up north, overall Karen says that predictive models show the future is looking pretty good for Arctic kelp forests.

In many other parts of the world, these ecosystems are shrinking, so it’s kind of cool that, as least to some extent, these losses are being offset up north. And a large expansion of underwater kelps might actually help slow climate change ever so slightly.

Just like trees on land, kelps rely on carbon dioxide to grow. Expanding kelp forests in the Arctic could become a pretty significant carbon sink. When these kelps die, they just drift slowly to the deep dark depths of the ocean, and because it’s so cold, they don’t really rot either. Instead, they just sit there, keeping corbon dioxide locked up at the bottom of the ocean.

There are other more tangible benefits to larger kelp forests too. It’s great habitat for marine life.

Karen: They’re going to have a higher canopy height and a higher biomass. This means that there’s more space for animals to live in. So basically more rooms in the house, more structure, more niches for different species to occupy.

It also probably will mean a shift in species. So most seaweeds and most kelps in the Arctic were almost kicked out in the last ice age and then they’ve been slowly inching their way back in. And some of them have done a better job and have adapted to these really extreme conditions, better than others.

Dan: Kelps aren’t the only thing that likes less sea ice. Us humans do as well. As sea ice decreases in both summer and winter, the formerly dark polar night that last for weeks or months, is now being lit up like never before by boats and the artificial light they bring in with them. This is a big deal to the multitudes of sea creatures that have adapted over millions of years to the darkness of the polar winter. One group of scientists is studying how this new influx of light is changing the behaviour of these animals.

Jørgen Berge: My name is Jørgen Berge, I’m a professor in marine biology at UIT, the Arctic University of Norway.

Dan: Jørgen, unlike most people, doesn’t actually mind the long dark, polar, winter. I spoke to him late last year, when the polar night in Norway had just begun

Jørgen: We actually just started the polar night items sitting now in Tromsø at 70 degrees north. The sun orbits around our horizon for 24 hours a day for two months in a row. There is still clear difference between day and night. But that difference becomes less and less the further north you get. And then once you get up to around 80 degrees, then the human eye is hardly able to distinguish any difference between night and day during the darkest part of the polar night.

But the polar night is certainly not just dark. It’s actually all about different kinds of light. Both background illumination from the sun, the aurora borealis the moon, also biological light.

Dan: Up until fairly recently, scientists used to think that the darkness of the polar night was uninteresting, devoid of life. But a research project that Jørgen started back in 2006 changed all that – and kind of by accident. His team was actually looking at how retreating sea ice would affect the marine ecosystem in an Arctic Fjord.

Jørgen: So we had to be there in the late autumn to deploy instruments that would then be in place and do measurements when the sun came back. But then as more or less a byproduct, the instruments were also doing measurements during the dark polar night. But when we got these data back, we started to realise that, hang on something, something is actually happening here.

Dan: What him and his team found changed scientists’ understanding of the polar night. The polar night isn’t not boring, far from it in fact.

Jørgen: So it’s a system that is in fact in full operation. Seabirds, fishes, zooplankton. It’s just so fascinatingly full of life during the, during the dark polar night.

Dan: One of the processes Jørgen and his colleagues has studied is called diel vertical migration.

Jørgen: That is the behaviour where organisms – zooplankton and fish – they move up from the deep up into the shallow, during nighttime and go migrate down into the deep, during daytime.

Dan: This is entirely controlled by light, so researchers just assumed it would stop. The polar night is just perpetual darkness after all.

Jørgen: It turns out that it doesn’t stop, it’s ongoing. One of the things that we have started to realise is how extremely intimately, these organisms are connected to the light climate, to ambient light.

Dan: Even with the sun gone during the winter months, light plays a huge role in the Arctic. The sun still brightens the sky ever so slightly as the earth rotates. Moon cycles also change light levels, and so does the aurora borealis. And creatures react to all of this. But when Jørgen and his colleagues were studying these creatures, they got conflicting data between the instruments they left alone over one winter and the data they collected from their boats. The reason was light pollution from the researchers themselves.

Jørgen: The first year we really didn’t fully really understand why the samples we took never matched the data that we got from acoustic instruments that had been deployed autonomously. But it turns out that these organisms, they are able to respond to extreme small levels of light.

Dan: Jørgen and his team need, well, light to work on their boat, so they use headlamps and floodlights and stuff. For ultra light-sensitive sea creatures, these lights are huge signals. Some swim towards them, some swim violently away. And not just animals near the surface. The team found this happening down to depths of 200 metres below the sea level.

The effect of light pollution could be happening on a large scale, thanks to melting sea ice and increased human presence.

Jørgen: As sea ice retreats, as we start fishing further north, oil and gas exploration, shipping, not the least, more and more human presence in the high Arctic during the polar night, then we also bring with us artificial lights. At the moment we are not able to, to, to say to which degree this really is a problem, but, that is one of the things that we are now really starting to look into.

A large ship covered in yellow lights illuminates the icy water.
Creatures which have adapted to the polar night over millions of years are now suddenly exposed to artificial light. Michael O. Snyder, Author provided

Dan: And melting sea ice, well that’s climate change.

Jørgen: So artificial light, it’s not of course a direct effect of climate change, but it’s certainly related to climate change because as it gets warmer, as there is less sea ice then we see more human presence and human presence will, it means there’s more artificial lights involved.

Dan: So what does this all mean for the fish, zooplankton and other sea creatures that are super-sensitive to light and live in this high Arctic environment? Jørgen says that’s a difficult question to answer.

Jørgen: Personally, I think that we have to look at the effects in two ways. One is the direct effect of light pollution. It does affect organisms there and then. Most likely that effect is limited, because it only last while there is artificial light there. And there’s certainly a limit to the, the geographical extent of that impact.

However, I think there’s another effect that is much more important. And that is how it’s affecting our knowledge about the polar night. To take one example, there’s more and more fisheries the high Arctic during the polar night. If you want to do surveys to give an estimate about how much there is of say haddock or cod, you have to do acoustic surveys with research vessels in the polar night, in where we are fishing. And these measurements might be strongly biased and impaired.

Dan: Essentially what Jørgen is saying is that every measure of arctic fisheries even taken in winter could be way off. By bringing in light, the fishermen and researchers change how fish and other animals behave. This is one of the oldest problems in biology: how to study ecosystems without disturbing them. And I asked him he feels as a scientist, to discover that his own presence could be distorting the results of his research.

Jørgen: Yeah, it sorta makes you feel unwanted. You know, that your presence is affecting the organisms, but it also, as a scientist, it also makes me, maybe wonder and questions. And I find it fascinating trying to understand things I cannot see.

It’s difficult to explain, but to me, when you really go, go up into the high Arctic and you allow yourself to be in the darkness and you start to take in all the senses, the sounds, the light, it’s just a, just a miracle sometimes.

I can still remember one on the experience we had. This was one of the first years when we were up on Svalbard in, early January, and I was out in a small boat out in the middle of the fjord and we turned off the engines. We turned off all lights because we wanted to look for seabirds. And we looked down and we saw this upside down sky filled with blue-green light, and that was just an amazing experience to see all this organisms from big jellies to small unicellular organisms blinking and glowing and moving in all directions. That was a beautiful sight.

Dan: What Jørgen saw was bio-luminescence – light produced by creatures in the Arctic night to communicate with each other. When you live in total darkness, light is, almost paradoxically, one of the most important and useful things there could possibly be. Even to the scientists who study it, the darkness of the polar night is so much more complex than anyone even imagined.

Gemma: I love the idea of the ocean blinking back at you, that’s just so beautiful as Jørgen said.

Dan: It made me want to take a vacation to the polar night in the middle of winter, which I’d never thought I’d say before. But, it is also dangerous, both Karen and Jørgen were talking about polar bears and how you actually have to carry guns, so it’s not all blinky lights and gorgeousness.

Dan: Both Karen and Jørgen have written for The Conversation as part of a series we’re running called Oceans 21. It examines the history and future of the world’s oceans. On The Conversation’s website, we’ve actually got a profile of every ocean on earth and Jørgen and Karen contributed to the one on the Arctic.

Dan: We’ve put a link to that, and the Oceans 21 series, in the show notes.

Gemma: Coming up, a group of archaeologists talk to us about some of their recent finds from Tanzania. But first, we’ve got a message with some recommended reading from Laura Hood, politics editor and assistant editor at The Conversation in London.

Laura Hood: Hello. My name is Laura Hood. I’m a politics editor for The Conversation here in London. I’ve got two recommendations this week. I worked with a team of psychologists led by Daniel Jolley from the University of Northumbria here in the UK. He told me about some work his team has been doing investigating how young people are being affected by conspiracy theories in the pandemic. Before they got in touch. I hadn’t realised that almost everything we know about conspiracy theories is based on work investigating adults. We know next to nothing about how children encounter and absorb misinformation. So they’ve been conducting surveys with British adolescents to try to work out at what age we’re most vulnerable to conspiracy theories and the extent to which young people are being exposed to them during lockdown. It’s really interesting reading, I think, particularly for parents.

I’d also like to recommend an article written by Mark Toshner, he’s an expert in respiratory medicine at the University of Cambridge. He’s put together a guide for anyone who’s feeling a bit overwhelmed by the scientific information that’s flying around about vaccines right now. He says, he feels really sorry for us trying to absorb all this information and he wants to make it a bit easier. So he’s tackling topics such as what it means when we hear that one vaccine is 90% effective, say, or another one is only 70% effective. Is that something we should be worrying about? Should we be trying to pick and choose our vaccines? He’s also talking about what it means for a vaccine to be potentially less effective against particular types of variant of COVID-19. So it’s useful information at this stage of the pandemic.

Daniel: That was Laura Hood from The Conversation in London.

Gemma: So for our next story, we’re heading to a warmer climate, thankfully, to Tanzania in East Africa and a place called the Olduvai Gorge. It’s known as the birthplace of humanity.

Dan: Birthplace, so how long we talking here?

Gemma: Ages, so about 2 million years or so. And today, archeologists from around the world, come to Olduvai to study the remains of different species of early humans. But scientists are also interested in the ancient environment and what the gorge actually looked like back then.

Dan: So is there a name for studying ancient climates?

Gemma: Yes, and it’s a great one. It’s paleoecology. So basically this is looking for evidence of ancient plants and pollen, and even bits of airborne charcoal by delicately sifting through layers of sediment. So we’ve been talking to a group of researchers who’ve been doing this work in a specific parts of the Olduvai Gorge called Ewass Oldupa, which actually means “the way to the gorge” in the Maa language of the local Masaai and what they’ve found has provided new insights into just how adaptable early humans were to the changing environment around them.

Julio Mercader: I’m Julio Mercader and I’m a professor with the University of Calgary, which is in Western Canada.

Gemma: OK, and we’re talking to you today, Julio, about your most recent research that’s just been published. It’s about an area in Tanzania, in East Africa. Can you just give me a bit of context? Why is this part of the world so important for our history?

Julio: Olduvai Gorge is in East Africa, and if you think of it as a region – there is this reef that is splitting the crust of the earth that is allowing volcanoes to spit out lava and ash. But at the same time as the splitting, it’s making the terrain sink. And when that happens, you have water building up that forms lakes and rivers and swamps. And because of that biodiversity tends to be really, really high because nature is a really productive in these kind of a rfit context.

Now in East Africa, which is where Olduvai is, the rift has been alive, so to speak, for more than 20 million years so that when humanity is forming, several million years ago, early humans, like any other animal, are being attracted to the resources that you find in the rift.

Now life near volcanoes was preserved because the eruptions and the sediments covered that up and then archaeologists exposed it. So now imagine an African Pompeii. But this time is much older. It is two million years. And instead of Romans, you want to imagine humans. But these humans are not like you and I, huh? They are early humans, several species. Unlike today when there is only one species. And among them on Olduvai Gorge, you have the first member of our genus, that we say in biology, and that is the genus homo. Right? And so to sum it up, Olduvai Gorge is important because many aspects of early human life have been buried, covered and preserved for posterity. And it’s not only the human fossils, but what we humans did on a daily basis, our activities.

And as you know, the gorge is like a canyon, it’s like a small version of the Grand Canyon. And because there is like a scar in the terrain, you can see the fossils in the remains, popping out from the walls that create the canyon.

Archaeologists working next to a tent on a hillside.
The research site at the Olduvai Gorge. Author provided (No reuse)

Gemma: So it seems like an incredibly important place for archaeologists like you and your colleagues. How long ago are we talking and is this a period of time when different species are actually competing for dominance?

Julio: Well, there is a lot we don’t know about this, but what we do know is that it was 2 million years ago. And at this point, what you have is humans belonging with a several genera. So for example, various homo habilis, and that species belongs with the same genus as you and I. But there is also paranthropus boisei, and other members of the australopithecines.

Now, are they competing directly with one another? From an ecological point of view, maybe not. Maybe not because we know that the adaptations, the morphology of the body, the cranial architecture, the diets may be a little different. So to explain this, imagine different species taking on different niches within the environment.

Gemma: OK, so let’s get into a bit more detail now about the research that you and your colleagues have recently published a paper on. What did you find?

Julio: We uncovered evidence that hominins were coming to a specific location within the gorge, which is on the western side of it. And, they kept coming back.

Gemma: To understand more about what the team of archaeologists found in the gorge, I spoke to two of the Tanzanians who’d worked on the study. Pastory Bushozi and Makarius Peter Itambu. I got them on a slightly dodgy line. So bear with us.

Pastory Bushozi: My name is Pastory Bushozi. I’m a senior lecturer at the University of Dar es Salaam, and archaeologist working on paleoanthropology.

Makarius: My name is Makarius, I’m a lecturer in archaeology, teaching human evolution, paleoenvironment and African stone age.

Gemma: What did you find? What did the ecology of the Olduvai gorge look like when these populations you were studying were living there 2 million years ago?

Makarius: The discovery revealed that the oldest Olduvai hominins used diverse but rapidly changing environments, that range from fern meadows, to woodland mosaics, but also natural band landscape to the lakeside. But also there’s woodland and palm groves, as well as steppes. Those were the kind of environment that looked like during 2 million years ago.

Gemma: So the landscape was changing, you were having forest, you having like a big steppe, you were having grasslands.

Makarius: Right, but the more interesting things, hominims continued to utilise the same toolkit, which is Olduwan. And this is so interesting because we believed that climatic change always trigger technological change, but in this scenario, hominins from Oldupa, it was the Oldupa site, maintain the very same toolkit, the Olduwan stone tools.

Gemma: You were seeing that they were using the same tools throughout that period?

Makarius: Yeah, that was so fascinating that despite of these rapid changes, adaptation to this major geomorphic and ecological transformation did not have any impact.

Gemma: Here’s Julio Mercader again.

Julio: What is interesting here is that over the course of 300,000 years, these Olduwan hominins are coming back to exploit different environments. And so what we have here for the first time is evidence in one place of the diversity of the adaptive tools and strategies that humanity is using to exploit many different ecologies and environments, showing an early example of great adaptability

Gemma: So you were seeing a real ability to use the environment to their benefit?

Julio: That is right. And so to me, this is a real landmark because there is technological dependence, but also the ability to adapt to whatever changes there are happening. And so, in a way it is like the very beginnings of the invasive behaviour typifies any other pioneer.

Gemma: Dr. Bushozi, can I bring you in there. I understand it was you who made one of the oldest discoveries?

Pastory: Yes, it was me, because actually I found those stone tools that were coming on the lower sequence. So I was excited, myself, and I called my colleague to come and see that. That day, everybody was excited. So by then we were collecting everything to see what we were going to do in the lab.

Gemma: And are you able to do research at the moment or is the pandemic stopping your research in the gorge?

Pastory: Because of the pandemic, we are not doing research, but still we are working on the lab. The work I’m doing now is to clean those stone tools by using chemicals so that I can get a good picture on those stone tools, and then after that we are also trying to do get what kind of raw materials, what kind of implement they were using to shape those tools. And then when we go back into the field, we’ll be able to find, trace now where those rocks were coming from.

Gemma: Thank you so much for your time, I really appreciate it.

Makarius and Pastory: Thank you so much.

Gemma: You can read more about the research in a piece that Julio Mercader wrote for The Conversation about their findings.

Alright, that’s it for this week. Thanks to all the academics who’ve spoken to us for this episode – and to The Conversation editors Natasha Joseph, Jack Marley, Hannah Hoag and Laura Hood.

Dan: You can find links to all the expert analysis we’ve mentioned in the episode – and tonnes of other recommended reading – in the show notes. And if you learnt loads and want to read more, click the link to sign up for our free daily email.

Gemma: This episode is co-produced by Mend Mariwany and me, with sound design by Eloise Stevens.

Dan: Our theme music is by Neeta Sarl. Final thanks also to Alice Mason, Stephen Khan and Imriel Morgan.

Gemma: Thanks for listening everybody. Until next time.

Read the original article here.
Cover photo by Francesco Ungaro on Unsplash.
Weakening Gulf Stream may disrupt world weather

Weakening Gulf Stream may disrupt world weather

By Tim Radford

The Gulf Stream is growing feebler, the Arctic seas are gaining fresh water. Together they could affect the world’s weather.

LONDON, 2 March, 2021 − The Atlantic Conveyer, otherwise the Gulf Stream − that great flow of surface water pouring northwards that overturns in the Arctic and heads south again at great depth − is now weaker than at any point in the last 1,000 years, European scientists report.

And in a second, separate but related study, researchers have found that the Beaufort Sea, in the Arctic, has gained two-fifths more fresh water in the last 20 years: water that could flow into the Atlantic to affect the Conveyor, and with it, climatic conditions.

Scientists call it the Atlantic Meridional Overturning Circulation or just AMOC. Europeans know it as the Gulf Stream: the current that conveys tropic warmth to their coasts and keeps Britain and Western Europe at a temperature several degrees higher than latitude alone might dictate.

And for years, oceanographers and climate scientists have been observing a slowing of the flow, by as much as 15%. But direct measurement of the great current began only relatively recently in 2004: researchers needed to know whether the slowdown was part of a natural cycle, or a consequence of climate change driven by global heating.

Now they know a little more. European researchers report in Nature Geoscience that they looked for evidence of ocean circulation shifts in what they call “proxy evidence”: the story of climate change told by tree growth rings, ice cores, ocean sediments, corals and historical records, including naval logbooks.

The combined evidence of temperature patterns, the sizes of particles of ocean floor sediment and the salinity and density of sub-surface water helps build up a picture of the Atlantic current for the last 1,600 years.

“The Gulf Stream System moves nearly 20 million cubic meters of water per second, almost a hundred times the Amazon flow”

The verdict? Up to the 19th century, ocean currents were stable. The flow is now more sluggish than at any time in the last millennium.

This is roughly what climate models have predicted: the warm salty water moves north, cools, becomes more dense, sinks to the deep and flows back south. But the Arctic has begun to warm, Greenland to melt, and the flow of fresh water into the northern seas to intensify.

Since the flow is driven by the difference in temperatures, any change in the regional thermometer will play back into the rate of flow. And any extra arrival of fresh water could further slow the overturning circulation.

“The Gulf Stream system works like a giant conveyor belt, carrying warm surface water from the equator up north, and sending cold, low-salinity deep water back down south. It moves nearly 20 million cubic meters of water per second, almost a hundred times the Amazon flow,” said Stefan Rahmstorf, of the Potsdam Institute for Climate Impact Research, in Germany, one of the authors.

“For the first time, we have combined a range of previous studies and found they provide a consistent picture of the AMOC evolution over the past 1600 years. The study results suggest that it has been relatively stable until the late 19th century.

“With the end of the Little Ice Age in about 1850, the ocean currents began to decline, with a second, more drastic decline following since the mid-20th century.”

Outcome awaited

The change could have ominous consequences for European weather systems: it could also deliver more intense coastal flooding to the US eastern seaboard. If the current continues to weaken, the consequences could be catastrophic.

Which is why a new study in Nature Communications matters so much. US researchers tracked the flow of fresh water from the Beaufort Sea − melt water from glaciers, rivers and disappearing Arctic sea ice − through the Canadian Archipelago and into the Labrador Sea.

Arctic water is fresher than Atlantic water, and richer in nutrients. But this extra volume, measured at a total of 23,300 cubic kilometres, could also affect the rate of flow of the overturning circulation. That is because relatively fresh water is less dense than saline water, and tends to float on top.

Quite what role it could play is uncertain: the message is that, sooner or later, it will escape into the North Atlantic. Then the world will find out.

“People have already spent a lot of time studying why the Beaufort Sea fresh water has gotten so high in the past few decades,” said Jiaxu Zhang,  of the Los Alamos National Laboratory, first author. “But they rarely care where the freshwater goes, and we think that’s a much more important problem.” − Climate News Network

This article was originally posted on the Climate News Network.
Cover photo by Michael Studinger, NASA (public domain), via Wikimedia Commons
Water, Climate, Conflict, and Migration: Coping with One Billion People on the Move by 2050

Water, Climate, Conflict, and Migration: Coping with One Billion People on the Move by 2050

By Nidhi Nagabhatla

Do migrants willingly choose to flee their homes, or is migration the only option available?

There is no clear, one-size-fits-all explanation for a decision to migrate — a choice that will be made today by many people worldwide, and by an ever-rising number in years to come due to a lack of access to water, climate disasters, a health crisis, and other problems.

Data is scarce on the multiple causes, or “push factors”, limiting our understanding of migration. What we can say, though, is that context is everything.

United Nations University researchers and others far beyond have been looking for direct and indirect links between migration and the water crisis, which has different faces — unsafe water in many places, and chronic flooding or drought in other places.

The challenge is separating those push factors from the social, economic, and political conditions that contribute to the multi-dimensional realities of vulnerable migrant populations — all of them simply striving for dignity, safety, stability, and sustainably in their lives.

A new report, Water and Migration: A Global Overview, from the UNU Institute for Water, Environment, and Health, offers insights into water and migration interlinkages, and suggests how to tackle existing gaps and needs.

The report’s information can be understood easily by stakeholders and proposes ideas for better informed migration-related policymaking. This includes a three-dimensional framework applicable by scholars and planners at multiple scales and in various settings.

The report also describes some discomforting patterns and trends, among them:

  • By 2050, a combination of water and climate-driven problems and conflicts will force 1 billion people to migrate, not by choice, but as their only option.
  • Links to the climate change and water crises are becoming more evident in a dominant trend — rural-urban migration.
  • There is a severe lack of quantitative information and understanding regarding direct, and indirect, water and climate-related drivers of migration, limiting effective management options at local, national, regional, and global scales.
  • Global agreements, institutions, and policies on migration are concerned mostly with response mechanisms; a balanced approach that addresses water, climate, and other environmental drivers of migration is needed.
  • Unregulated migration can lead to rapid, unplanned, and unsustainable settlements and urbanisation, causing pressure on water demand and increasing the health risks and burdens for migrants, as well as hosting states and communities.
  • Migration should be formally recognised as an adaptation strategy for water and climate crises; while it is viewed as a “problem”, in fact it forms part of a “solution”.
  • Migration reflects the systemic inequalities and social justice issues pertaining to water rights and climate change adaptation; lack of access to water, bad water quality, and a lack of support for those impacted by extreme water-related situations constitute barriers to a sustainable future for humankind.

Case studies in the report provide concrete examples of the migration consequences in water- and climate-troubled situations, including:

  • the shrinking of Lake Chad in Africa, and the Aral Sea in Central Asia;
  • the saga of Honduran refugees;
  • the rapid urbanisation of the Nile Delta; and
  • the plight of island nations facing both rising seas and more frequent, more intense extreme weather events; in addition, the added health burdens imposed on people and communities by water pollution and contamination create vicious cycles of poverty, inequality, and forced mobility

While the Sustainable Development Goals (SDGs) do not include an explicit migration target, mitigation of migration should be considered in the context of SDGs that aim to strengthen capacities related to water, gender, climate, and institutions. These issues resonate even as the world deals with the COVID-19 pandemic.

Recent news stories have chronicled the plight of desperate migrant workers trapped in the COVID-19 crisis in India, and of displaced people in refugee camps where social distancing is unachievable, as is access to soap and water, the most basic preventive measure against the disease.

Add to that the stigma, discrimination, and xenophobia endured by migrants that continue to rise during the pandemic.

Even at this moment, with the world fixated on the pandemic, we cannot afford to put migration’s long-term causes on the back burner.

While the cost of responses may cause concerns, the cost of no decisions will certainly surpass that. There may be no clear, simple solution but having up-to-date evidence and data will surely help.

On World Environment Day (5 June), we were all encouraged to consider human interdependencies with nature.

Let us also acknowledge that water and climate-related disasters, ecological degradation, and other environmental burdens cause economic, health, and well-being disparities for migrants and populations living in vulnerable settings.

This article was first published by Inter Press Service News.
Cover photo by International Organization for Migration / Sibylle Desjardins
Rivers flood, seas rise – and land faces erosion

Rivers flood, seas rise – and land faces erosion

By Tim Radford

Polar melting cannot be separated from farmland soil erosion and estuarine flooding. All are part of climate change.

Climate heating often ensures that calamities don’t come singly: so don’t forget what erosion can do.

In a warmer world the glaciers will melt ever faster to raise global sea levels ever higher. In a wetter world, more and more topsoil will be swept off the farmlands and downriver into the ever-rising seas.

And the pay-off of silt-laden rivers and rising sea levels could be catastrophic floods, as swollen rivers suddenly change course. Since many of the world’s greatest cities are built on river estuaries, lives and economies will be at risk.

Three new studies in two journals deliver a sharp reminder that the consequences of global heating are not straightforward: the world responds to change in unpredictable ways.

First: the melting of the ice sheets and the mountain glaciers. Researchers warn in the journal Nature Climate Change that if the loss of ice from Antarctica, Greenland and the frozen rivers continues, then climate forecasters and government agencies will have to think again: sea levels could rise to at least 17cms higher than the worst predictions so far.

“Avulsions are the earthquakes of rivers. They are sudden and sometimes catastrophic. We are trying to understand where and when the next avulsions will occur”

That means an additional 16 million people at hazard from estuarine floods and storm surges.

In the last 30 years, the flow from the Antarctic ice cap has raised sea levels by 7.2mm, and from Greenland by 10.6mm. Every year, the world’s oceans are 4mm higher than they were the year before.

“Although we anticipated the ice sheets would lose increasing amounts of ice in response to the warming of the oceans and the atmosphere, the rate at which they are melting has accelerated faster than we could have imagined,” said Tom Slater of the University of Leeds, in the UK, who led the research.

“The melting is overtaking the climate models we use to guide us, and we are in danger of being unprepared for the risks posed by sea level rise.”

Dr Slater and his colleagues are the third team to warn in the last month that observations of climate already match the worst-case scenarios dreamed up by forecasters preparing for a range of possible climate outcomes.

Erosion risk rises

The latest reading of glacial melt rates suggests that the risk of storm surges for many of the world’s greatest cities will double by the close of the century. But coastal cities – and the farmers who already work 38% of the terrestrial surface to feed almost 8bn people – have another more immediate problem.

In a warmer world, more water evaporates. In a warmer atmosphere, the capacity of the air to hold moisture also increases, so along with more intense droughts, heavier rainfall is on the way for much of the world. And the heavier the rain, or the more prolonged the drought, the higher the risk of soil erosion.

In 2015 the world’s farmers and foresters watched 43 billion tonnes of topsoil wash away from hillsides or blow away from tilled land and into the sea. By 2070, this burden of silt swept away by water or blown by wind will have risen by between 30% and 66%: probably more than 28 bn tons of additional loss.

This could only impoverish the farmland, according to a study by Swiss scientists in the Proceedings of the National Academy of Sciences. It could also impoverish people, communities and countries. The worst hit could be in the less developed nations of the tropics and subtropics.

But the flow of ever-higher silt levels into ever-rising seas also raises a new hazard: hydrologists call it river avulsion. It’s a simple and natural process. As conditions change, so rivers will naturally change their flow to spill over new floodplains and extend coastal lands.

Survival in question

But river avulsions can also be helped along by rising sea levels. Since 10% of humanity is crowded into rich, fertile delta lands, and since some of the deadliest floods in human history – two in China in 1887 and 1931 claimed six million lives – have been caused by river avulsions, the question becomes a matter of life and death.

US scientists report, also in the Proceedings of the National Academy of Sciences, that rising sea levels alone could make abrupt river avulsion more probable, especially as delta lands could be subsiding, because of groundwater and other extraction.

The dangers of avulsion are affected by the rate of sediment deposit in the river channels, and this is likely to rise with sea levels. This in turn raises the level of the river and eventually a breach of a levee or other flood defence will force the river to find a swifter, steeper path to the sea.

Cities such as New Orleans and the coastal communities of the Mississippi delta are already vulnerable. “Avulsions are the earthquakes of rivers,” said Michael Lamb, of California Institute of Technology, one of the authors.

“They are sudden and sometimes catastrophic natural events that occur with statistical regularity, shifting the direction of major rivers. We are trying to understand where and when the next avulsions will occur.” – Climate News Network

This article was originally posted on The Climate News Network.
Iran: decades of unsustainable water use has dried up lakes and caused environmental destruction

Iran: decades of unsustainable water use has dried up lakes and caused environmental destruction

By Zahra Kalantari, Davood Moshir Panahi, Georgia Destouni

Salt storms are an emerging threat for millions of people in north-western Iran, thanks to the catastrophe of Lake Urmia. Once one of the world’s largest salt lakes, and still the country’s largest lake, Urmia is now barely a tenth of its former size.

As the waters recede, extensive salt marshes are left exposed to the wind. These storms are getting saltier and are now happening more often – even in the cold and rainy seasons of the year. As more drying uncovers more salt marshes, things will only get worse.

Salt storms pose a direct threat to the respiratory health and eyesight of at least 4 million people living in both rural and urban areas around Lake Urmia. Increasing soil salinity reduces the yield of agricultural and orchard crops grown around the lake, while the lake has shrunk so much that boating is no longer possible, resulting in a loss of tourism.

Urmia 1986-2016. Salt marshes have been exposed as the lake has shrunk. (Source: Google Timelapse)

This dramatic decline is down to human activity. Over the past three decades, Iran has followed a succession of five-year economic development plans, part of which involved providing large government loans for the agricultural sector to expand and switch from being primarily rain-fed to irrigated. To provide the necessary water for the farms, as well as for growing domestic and industrial use, more than 50 dams were constructed on rivers that drain much of north-western Iran and flow into the lake.

While these dams siphoned off the water that once fed the lake, the drying process was intensified by climate change. The rate of rainfall has reduced in recent decades and the Urmia basin has experienced several multi-year droughts.

All this has left a massively shrunken lake and a host of associated economic, social and health impacts. Yet what’s happening with Lake Urmia is just one example of water-environmental problems emerging right across Iran.

Iran is getting warmer and drier

In a recent journal article, we examined how both climate change and human activity had affected hydrological changes in Iran in recent decades. The country has 30 main river basins, and we gathered three decades of key hydro-climatic data for each, including surface temperature, precipitation, how much water was stored underground in soil and rock, surface runoff (the amount of excess rainwater that cannot be absorbed by the soil), and measures of evaporation and transpiration from plants.

We then calculated the average values of each of these variables over two 15-year periods, 1986-2001 and 2002-2016, and compared the two. This allowed us to see what was changing in each of these basins and by how much.

Our work showed that Iran’s main river basins have got warmer but are receiving less precipitation, are storing less water underground, and seeing less runoff.

Rusting boat on salty ground, lake and mountains in distance.
A boat is left to rust as Lake Urmia shrinks. Tolga Subasi / shutterstock

Some river basins where precipitation and runoff decreased still saw an increase in evapotranspiration (the sum of evaporation and plant transpiration). This may seem odd at first, as less rainwater surely means there is less water to evaporate or for plants to transpire. Lake Urmia, for instance, is an endorheic basin, which means nothing flows out of it and all water that flows in eventually evaporates (this is why the lake is salty). But why would evapotranspiration have actually increased, even as the basin is fed by less water?

This is actually an indicator of human activity. First, all those dams generally increase the surface area of the body of water, compared to the natural flow before the dam was built. Artificial lakes and reservoirs, therefore, leave more water exposed to air and direct sunlight, thus increasing evaporation.

But it’s also down to farming. As more crops are grown, more water is transpired by plants – and more water is needed to grow those plants. To add water where needed, farmers have turned to groundwater and large-scale water transfer engineering projects.

This use of water to maintain and expand human activities is unsustainable and has serious environmental and socio-economic consequences, particularly in this dry part of the world, as seen by changes to Lake Urmia. Policymakers need to mitigate the adverse hydrological changes and associated socio-economic, environmental and health impacts, and move towards something more sustainable.

This article was originally posted on The Conversation.
Cover photo of Lake Urmia, Iran from Flickr by Ninara.
UCCRTF backs training for improved early flood warning in Central Viet Nam

UCCRTF backs training for improved early flood warning in Central Viet Nam

By Trang Dinh and Bas Stengs

Modernizing flood forecasting and warning often comes with the requirements of knowledge transfer and expertise enhancement for forecasters, decision makers, and the residents in local communities. To ensure that the Flood Forecasting and Warning System that is being built for Hoi An city and VGTB Basin — a major catchment in Viet Nam—is able to operate effectively, an extensive collaborative modelling and training programme was held from July 2019 to February 2020, with support from the Urban Climate Change Resilience Trust Fund (UCCRTF).

The on-the-job training program was held in Tam Ky, Quang Nam, the mid-central province of Vietnam under ADB Grant 0462-VIE[1]: Urban Environment and Climate Change Adaptation Project. Key deliverables of the project are: 

  1.  a Flood Forecasting and Warning System (FFWS);
  2. supporting the Provincial Hydrological and Meteorological Centre;
  3. a Decision Support System (DSS); and,
  4.  supporting the Provincial Steering Committee for Disaster Prevention, Search and Rescue (PSCDPSR).​
Officers of Standing Office of Provincial Steering Committee for Natural Disasters Prevention, Search and Rescue participating in the Decision Support System training, February/2020, in Tam Ky, Quang Nam Province. Credit to Dang Thi Kim Nhung, Emergency communication & Management Specialist of Vietnam Institute of Water Resources Planning.

The project, underway since March 2018, is led by a consortium of Deltares (Netherlands), HaskoningDHV Nederland B.V. (Netherlands), SUEZ Consulting (SAFEGE) (France) and the Institute for Water Resources Planning (Vietnam).  The FFWS and DSS for the Vu Gia-Thu Bon river system, was considered to be one of the most urgent (non-structural) project measures. The FFWS system is designed to improve the procedures for flood warning and timely evacuation, while the DSS enables the analysis of both structural and non-structural measures regarding flood management, and the study of water shortage problems and salinity intrusion during dry periods.

The project applied a state-of-art flood early warning system, called “Delft FEWS” – an open, flexible, free-of-charge software package developed by Deltares, to the Vu Gia Thu Bon river basin. This was paired with an upgraded MIKE river basin modelling package and a new Delft3D marine model to create an integrated FFWS.

​Training to ensure long term sustainability

The goal of the training is to ensure the long-term sustainability of the FFWS, by building the capabilities of system developers and operators. A collaborative approach was deployed through a series of technical on-the-job training sessions, allowing participants to gain knowledge and know how to operate and maintain the FFWS and DSS in the future. The specific objective of the technical working and training sessions was to train the staff in using the calibrated models and operate the FFWS and DSS, and to teach them the process of building, calibrating and maintaining the systems.

​One participant, Mr. Truong Xuan Ty, Chief of Standing Office of the Provincial Steering Committee for Disaster Prevention, Search and Rescue, said “we currently don’t use any forecasting software. If we can better understand the flood forecasting and flood warning models, by using the FFWS+DSS, this will greatly improve the efficiency of the decision making and will speed up the warnings to the communities”.

​A total of nine training sessions were delivered to end users such as the Provincial Hydro-Met Centre (PHMC), the Mid-Central Regional Hydro-Met Centre (RHMC) and the Provincial Steering Committee for Disaster Prevention, Search & Rescue (PSCDPSR). The training was divided into two main components: (i) Catchment and river model development and (ii) Delft-FEWS flood early warning system configuration and operation.

​The on-the-job training was organized at the end users’ location in Tam Ky city, Quang Nam province. Priority was given to the group of potential operators: forecasters from PHMC and RHMC and technical officers from PSCDPSR, by delivering intensive instructions and knowledge ensuring as much interaction as possible between trainers and trainees. Characteristics of the training sessions included: 

  • Each technical session introduced a specific topic providing expertise on applicable tools, software, features, required data, know-how to self-configure and operate the models through various practical exercises.
  • Demo versions pre-configured for the project were provided for demonstration and practice during and after each session.  
  • The demo versions were updated to reflect comments and requests from end users during and after each session. Agile work plans for the following sessions were arranged together with the end-users at the end of each session, to incorporate the user needs as much as possible.

​The training was designed and lead international consultants. Because most local officers are not fluent in English, language barriers were a considerable challenge. To overcome this, a Vietnamese user interface was developed for both software systems and the training was delivered in Vietnamese by local trainers.

​With the final training session held in February this year, a recap of the complete training was done with lots of room for interaction, by means of a Q&A session and a variety of user-selected practical exercises, such as the Delft-FEWS basic configuration and river catchment model set-up. The fact that most exercises were completed with little or no support from the trainers proved that the local skills on modelling, flood forecasting and warning had significantly improved through the concept of “learning by doing”. 

​For further information about the project and the training, please contact the authors: Bas Stengs ( or Trang Dinh (

This article was originally posted on the Asian Development Bank Livable Cities Blog.
Cover image by Ngocnb at Vietnamese Wikipedia
Greening the grey in Washington DC – a resilience success story

Greening the grey in Washington DC – a resilience success story

The pioneering infrastructure project to upgrade Washington DC’s combined sewer system used green infrastructure to reduce capital cost and build resilience to future flood risk. DC Water, the District of Colombia’s Water and Sewer Authority, adapted the $2.6 billion-dollar project to incorporate $100 million dollars of green infrastructure.

A new case study, produced by Acclimatise for The Resilience Shift, tells the story of DC Water’s journey to incorporate green infrastructure into such a large and important critical infrastructure project. From inventing the world’s first Environmental Impact Bond to finance the project, to delivering a jobs programme that allowed DC residents to maintain the green infrastructure, the Clean Rivers Project innovated at each stage of the development process.

Read the full case study

DC Water, embarked on the Clean Rivers Project to managing combined sewer overflow events by implementing green infrastructure above ground, alongside grey infrastructure below ground, to help control the volume of water reaching the storm water drainage system. Like many older U.S. cities, DC has a combined sewer system. During heavy rainfall events the capacity of the combined system can be exceeded, resulting in combined sewage and stormwater discharge into DC’s river.

Phase one of the Clean Rivers Project in the Rock Creek Area of DC, includes implementing green infrastructure techniques such as bio retention (e.g. rain gardens) in curb extensions and planter strips, and permeable pavements on streets and alleys that will can manage the volume associated with 1.2 inches of rain falling on 365 impervious acres of land. Just as underground tunnels are designed to a given holding capacity, the green infrastructure was likewise designed to manage certain volume of rainfall.

The green infrastructure was financed by the first of its kind Environmental Impact Bond (EIB) where both the investors and DC Water, hedge the financial risks and share the benefits. If the green infrastructure performs better than expected at reducing storm water runoff, DC Water will make an outcome-based payment to the investors. If the green infrastructure underperforms at reducing runoff, the investors will make a risk-share payment to DC Water. If performance falls within the expected outcome range then neither party will make a payout.

The results of phase one are presently being monitored and evaluated to understand the green infrastructure efficacy to attenuate the stormwater, although are expected to deliver a range of benefits beyond reducing the occurrence of CSO events.  This includes creating local employment opportunities through installation and maintenance, improving the micro-climate and building climate change resilience and reducing crime through greener communities.

This case study offers important insights to other municipalities struggling to manage CSO overflows, and shows how green infrastructure can be implemented, in partnership with other city programs, to achieve win-win measures. In particular, city planners, the water and sewage authority, environmental departments and organizations focused on urban regeneration, climate resilience and mitigation and more broadly environmental causes, can implement green infrastructure to achieve multiple objectives in tandem in a cost-effective way. The innovative financing approach can also be readily replicated in other context.

Access the full case study here

This article was originally posted on The Resilience Shift website.
Less rain will fall during Mediterranean winters

Less rain will fall during Mediterranean winters

By Tim Radford

A warmer world should also be a wetter one, but not for the cockpit of much of human history: Mediterranean winters will become increasingly parched. Winter rainfall – and winter is the rainy season – could see a 40% fall in precipitation.

Agriculture and human civilisation began in the Fertile Crescent that runs from eastern Turkey to Iraq: cattle, sheep and goats were domesticated there; the first figs, almonds, grapes and pulses were planted there; the progenitors of wheat were sown there.

Cities were built, irrigation schemes devised, empires rose and fell. Greece colonised the Mediterranean, Rome later controlled it and set the pattern of law and civic government for the next 2000 years in Northern Europe.

Islamic forces brought a different civilisation to the Balkans, North Africa and almost all of Spain. The grain fields of the Nile Valley underwrote the expansion of the Roman Empire.

“What’s really different about the Mediterranean is the geography. You have a big sea enclosed by continents, which doesn’t really occur anywhere else in the world”

But the pressure of history is likely to be affected by the high pressure of summers to come. In a world of rapid climate change, the already dry and sunny enclosed sea will become sunnier and drier, according to two scientists from the Massachusetts Institute of Technology.

They report in the American Meteorological Society’s Journal of Climate that the winter rains that are normally expected to fill the reservoirs and nourish the rich annual harvest from the orchards, vineyards and wheat fields can be expected to diminish significantly, as atmospheric pressures rise, to reduce rainfall by somewhere between 10% and 60%.

Ordinarily, a warmer world should be a wetter one. More water evaporates, and with each degree-rise in temperature the capacity of the air to hold water vapour increases by 7%, to fall inevitably as rain, somewhere.

But episodes of low pressure associated with rain clouds over the Mediterranean become less likely, according to climate simulations. The topography of the landscape and sea determines the probable pattern of the winds.

High pressure grows

“It just happened that the geography of where the Mediterranean is, and where the mountains are, impacts the pattern of air flow high in the atmosphere in a way that creates a high-pressure area over the Mediterranean,” said Alexandre Tuel, one of the authors.

“What’s really different about the Mediterranean compared to other regions is the geography. Basically, you have a big sea enclosed by continents, which doesn’t really occur anywhere else in the world.”

Another factor is the rate of warming: land warms faster than sea. The North African seaboard and the southern fringe of Europe will become 3 to 4°C hotter over the next hundred years. The sea will warm by only 2°C. The difference between land and sea will become smaller, to add to the pattern of high pressure circulation.

“Basically, the difference between the water and the land becomes smaller with time,” Tuel says.

Frequent warnings

Once again, the finding is no surprise: Europe has a long history of drought and flood, but drought tends to leave the more permanent mark. The eastern Mediterranean has already experienced its harshest drought for 900 years and this has been linked to the bitter conflict in Syria.

Researchers have repeatedly warned that the pattern of drought on the continent is likely to intensify, and at considerable economic and human cost.

What is different is that the latest research offers detailed predictions of the nature of change, and identifies the regions likeliest to be worst hit. These include Morocco in north-west Africa, and the eastern Mediterranean of Turkey and the Levant.

“These are areas where we already detect declines in precipitation,” said Elfatih Eltahir, the senior author. “We document from the observed record of precipitation that this eastern part has already experienced a significant decline of precipitation.” 

This article was originally posted on the Climate News Network.
Image: By Mohamed Hozyen, via Wikimedia Commons