The Maldives is located in the Indian Ocean and comprised of 1192 coral islands, it is also the world’s lowest lying country. At its highest point it is only 2.4 meters above sea level. As such, water has been the lifeline of the islands for most of the past. With climate change, however, it is increasingly becoming a threat. On the one hand parts of the Maldives ae experiencing drinking water shortages, while others are regularly being flooded. Rising ocean temperatures and acidification are also affecting coral reefs, which are crucial for many local livelihoods.
In this United Nations Development Programme (UNDP) video, we see the efforts undertaken in the Maldives to help vulnerable communities with climate change induced water shortages. The “Supporting vulnerable communities in Maldives to manage climate change-induced water shortages” project is being implemented by the Ministry of Environment and Energy. The project targets 49 islands across of 13 atolls that experience water shortages linked to low rainfall and extended dry periods, brought on by a changing climate. It aims to provide safe and reliable freshwater to 105,000 people, roughly 30 percent of the island nation’s residents.
Watch the video below to learn more about this project and howthe Maldives are adapting to climate change related water shortages:
The nation’s two largest reservoirs, Lake Mead on the Arizona/Nevada border and Lake Powell on the Arizona/Utah border, were brim full in the year 2000. Four short years later, they had lost enough water to supply California its legally apportioned share of Colorado River water for more than five years. Now, 17 years later, they still have not recovered.
This ongoing, unprecedented event threatens water supplies to Los Angeles, San Diego, Phoenix, Tucson, Denver, Salt Lake City, Albuquerque and some of the mostproductive agricultural lands anywhere in the world. It is critical to understand what is causing it so water managers can make realistic water use and conservation plans.
While overuse has played a part, a significant portion of the reservoir decline is due to an ongoing drought, which started in 2000 and has led to substantial reductions in river flows. Most droughts are caused by a lack of precipitation. However, our published research shows that about one-third of the flow decline was likely due to higher temperatures in the Colorado River’s Upper Basin, which result from climate change.
This distinction matters because climate change is causing long-term warming that will continue for centuries. As the current “hot drought” shows, climate change-induced warming has the potential to make all droughts more serious, turning what would have been modest droughts into severe ones, and severe ones into unprecedented ones.
How climate change reduces river flow
In our study, we found the period from 2000 to 2014 is the worst 15-year drought since 1906, when official flow measurements began. During these years, annual flows in the Colorado River averaged 19 percent below the 20th-century average.
During a similar 15-year drought in the 1950s, annual flows declined by 18 percent. But during that drought, the region was drier: rainfall decreased by about 6 percent, compared to 4.5 percent between 2000 and 2014. Why, then, is the recent drought the most severe on record?
The answer is simple: higher temperatures. From 2000 to 2014, temperatures in the Upper Basin, where most of the runoff that feeds the Colorado River is produced, were 1.6 degrees Fahrenheit higher than the 20th-century average. This is why we call this event a hot drought. High temperatures continued in 2015 and 2016, as did less-than-average flows. Runoff in 2017 is expected to be above average, but this will only modestly improve reservoir volumes.
High temperatures affect river levels in many ways. Coupled with earlier snow melt, they lead to a longer growing season, which means more days of water demand from plants. Higher temperatures also increase daily plant water use and evaporation from water bodies and soils. In sum, as it warms, the atmosphere draws more water, up to 4 percent more per degree Fahrenheit from all available sources, so less water flows into the river. These findings also apply to all semi-arid rivers in the American Southwest, especially the Rio Grande.
A hotter, drier future
Knowing the relationship between warming and river flow, we can project how the Colorado will be affected by future climate change. Temperature projections from climate models are robust scientific findings based on well-tested physics. In the Colorado River Basin, temperatures are projected to warm by 5°F, compared to the 20th-century average, by midcentury in scenarios that assume either modest or high greenhouse gas emissions. By the end of this century, the region would be 9.5°F warmer if global greenhouse gas emissions are not reduced.
Using simple but strong relationships derived from hydrology models, which were buttressed by observations, we and our colleagues calculated how river flows are affected by higher temperatures. We found that Colorado River flows decline by about 4 percent per degree Fahrenheit increase, which is roughly the same amount as the increased atmospheric water vapor holding capacity discussed above. Thus, warming could reduce water flow in the Colorado by 20 percent or more below the 20th-century average by midcentury, and by as much as 40 percent by the end of the century. Emission reductions could ease the magnitude of warming by 2100 from 9.5°F to 6.5°F, which would reduce river flow by approximately 25 percent.
Large precipitation increases could counteract the declines that these all-but-certain future temperature increases will cause. But for that to happen, precipitation would have to increase by an average of 8 percent at midcentury and 15 percent by 2100.
Moreover, climate models do not agree on whether future precipitation in the Colorado Basin will increase or decrease, let alone by how much. Rain gauge measurements indicate that there has not been any significant long-term change in precipitation in the Upper Basin of the Colorado since 1896, which makes substantial increases in the future even more doubtful.
Megadroughts, which last anywhere from 20 to 50 years or more, provide yet another reason to avoid putting too much faith in precipitation increases. We know from tree-ring studies going back to A.D. 800 that megadroughts have occurred previously in the basin.
March of 2017 was the warmest March in Colorado history, with temperatures a stunning 8.8°F above normal. Snowpack and expected runoff declined substantially in the face of this record warmth. Clearly, climate change in the Colorado River Basin is here, it is serious and it requires multiple responses.
It takes years to implement new water agreements, so states, cities and major water users should start to plan now for significant temperature-induced flow declines. With the Southwest’s ample renewable energy resources and low costs for producing solar power, we can also lead the way in reducing greenhouse gas emissions, inducing other regions to do the same. Failing to act on climate change means accepting the very high risk that the Colorado River Basin will continue to dry up into the future.
While India’s diminishing groundwater is widely attributed to over extraction, especially in the northern agricultural belts of Punjab and Haryana, the study holds decline in rainfall caused by the rise in the temperatures in the Indian Ocean — a major factor in monsoonal rainfall patterns over the Indo-Gangetic Plain — to be a more important cause.
“This study adds another dimension to the existing water management framework. We need to consider not just the withdrawals but also the deposits in the system,” says Yoshihide Wada, co-author of the study and deputy director, Water Programme, International Institute for Applied Systems Analysis, Austria.
“This indirectly suggests that the declining trends may continue in the future because of this warming — which can affect water availability in the region.” – Vimal Mishra, lead author
Importantly, the study finds links between the rise in sea surface temperatures of the Indian Ocean and the declining monsoonal rainfall which the study’s lead author Vimal Mishra says may be linked to climate change, though this is yet to be scientifically proven.
“Rise in the sea surface temperature in the Indian Ocean affects the rainfall in the Indo-Gangetic Plain. The long-term decline in rainfall in the Indo-Gangetic Plain is related to temperature in the Indian Ocean. This indirectly suggests that the declining trends may continue in the future because of this warming — which can affect water availability in the region,” Mishra, who is also an assistant professor at the Indian Institute of Technology, Gandhinagar, tells SciDev.Net.
India relies heavily on groundwater for irrigation particularly in the dry northern regions where precipitation is scarce. Groundwater withdrawal has increased tenfold — from 10-20 cubic kilometres per year in 1950 to 240-260 cubic kilometres in 2009. Satellite imagery shows major declines in groundwater, particularly in northern India.
India should avoid growing water-intensive crops in water-stressed regions such as Punjab, Mishra tells SciDev.Net. He also suggests the development of policies and technology to improve groundwater recharge during the monsoon season and also improvement of irrigation efficiency through adoption of scientific methods such as the use of sprinkler and drip systems.
According to a report by the Punjab Agricultural University (PAU), more than 1.3 million tube wells irrigate 73 per cent of agricultural land in Punjab where the total annual demand for irrigation is 4.76 million hectare metres.
Punjab, as per the PAU report, accounts for only 1.5 per cent of India’s geographical area but contributes 35 per cent and 60 per cent of India’s rice and wheat granaries, respectively.
With droughts set to become more frequent due to global warming, delivering timely, long-term weather forecasts to farmers in the developing world will be key to limiting damage and saving lives, the head of the U.N. food agency said on Monday.
Droughts have killed more than 11 million people worldwide since 1900 and now affect double the land area than in 1970, according to the U.N. Food and Agriculture Organization (FAO). Developing countries are the most exposed, with their agricultural sectors shouldering 80 percent of all damage caused by drought, FAO says.
Better access to reliable weather data and early warning systems could help farmers in rural areas get ready to endure long spells of no rain, said FAO director-general Jose Graziano da Silva. “Most of the times poor rural communities in developing countries don’t even know that a drought is about to strike,” he told a conference at the FAO headquarters in Rome. Measures such as planting resistant crops and building water reservoirs can greatly reduce the impact of droughts, but international responses too often focus on emergency relief, said Graziano da Silva. “People die because they are not prepared to face the impacts of the drought – because their livelihoods are not resilient enough,” he said.
In Rome, FAO and the World Meteorological Organization (WMO) signed an accord to increase cooperation in the face of climate change, improving agro-meteorological services to help small farmers prepare for droughts. WMO secretary general Petteri Taalas said weather forecast accuracy had greatly increased in recent years thanks developments in satellite, computing and scientific research. “Weather forecasts are not anymore a joke, they are something you can very much rely on,” he told the conference.
Know-how related to long-term forecasts and prediction of major climate events like El Niño had to be shared between rich and poor countries, he added. The last El Niño, a warming of ocean surface temperatures in the eastern and central Pacific that typically occurs every few years, subsided in 2016 and was linked to crop damage, fires, and flash floods.
Reporting by Umberto Bacchi @UmbertoBacchi, Editing by Ros Russell. Article originally posted on Zilient.org. Credit: Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women’s rights, trafficking, property rights, climate change and resilience. Visit http://news.trust.org
This is an excerpt from a newly published article on Atavist. To read the full article please click here.
By Will Bugler
India has a tempestuous relationship with water. The seasonal monsoon winds drive dramatic changes to the country’s weather systems, blowing in wet weather from the south-west, or dry from the north-east. The rainfall brought by these weather systems does not fall uniformly across the country, with some areas suffering intense droughts, while others experience severe floods. The dualism of overabundance and scarcity of water presents huge challenges for the country’s growing urban population, whose health, homes and livelihoods are increasingly threatened by India’s water woes.
Water issues affect India’s burgeoning cities in several ways. Surging demand for drinking, sanitation and industry, is putting pressure on scarce resources, while at the same time, the impact of severe flood events is felt most keenly by the poorest city dwellers, who often live in poor quality housing, and in low-lying areas. So what can be done to manage urban water resources in a land of floods and droughts?
India’s cities are growing fast. By 2030 the country’s urban population is expected to reach 600 million, as opposed to today’s almost 400 million. Gorakhpur in Uttar Pradesh is one of these fast-growing cities.
As is often the reality when urbanisation moves at such high rates, local and municipal governments have difficulties keeping up with the provision of essential infrastructure, especially in informal settlements. This leads to several problems, a very prominent one being missing sewerage systems.
In Gorakhpur, this has become a serious issue in the transitional areas between the city and the rural surroundings, i.e. the peri-urban areas. They have become dumping grounds for sewage and garbage that is collected from the streets. This not only pollutes arable land, but it also contaminates water. During heavy rainfall or floods, the sewage piles dilute and run off into nearby rivers and waterways. This has serious health implications for the local population.
Fortunately, change is underway. Communities in Gorakhpur have started treating their wastewater before releasing it into surrounding fields and rivers using Decentralized Wastewater Treatment Systems (DEWATS).
To learn more about these efforts, watch the short film below.
Climate change impacts on water are well documented, from floods to droughts hydrological climate impacts affect the lives and livelihoods of millions of people around the world. One aspect of the issue that is, perhaps, less well reported is that of climate impacts on wastewater. In an effort to correct this, the UN has made wastewater its theme for this year’s World Water Day.
The issue of wastewater and water reuse is becoming increasingly important. The vast majority of wastewater entering the natural environment untreated, and with millions of people, mostly in developing countries, forced to drink wastewater that is contaminated with human faeces, the issue has serious implications for human health and development.
The recent UN Sustainable Development Goals (SDGs) set a target for reducing by half, the amount of wastewater that enters the environment untreated by the year 2030. But what can be done to achieve this? And how might climate change impact wastewater treatment and reuse? To find out more Acclimatise spoke with Johannes Cullmann, Head of Climate and Water at the World Meteorological Organisation (WMO).
Higher costs of water as a result of droughts and floods linked to climate change are severely affecting corporate financial performance globally. Companies worldwide are being warned that taking water preservation measures is now vital, and that those whole fail to act are likely to face mounting financial losses.
The Carbon Disclosure Project (CDP), a not-for-profit organisation that tracks corporate environmental performance, says a combination of droughts and floods linked to climate change, plus a tightening of water regulations, are costing companies billions of dollars.
In a new report, Thirsty business: Why water is vital to climate action, CDP says data supplied by more than 600 companies around the world showed that corporate costs related to water amounted to US$14 billion over the last financial year. These costs include preservation measures put in place by many companies.
Drought also affected the operations of the US multinational General Motors, which says it incurred costs of $8 million in 2015 due to drought conditions at various locations, and also because of higher utility charges.
The CDP report says progress on water issues and on cutting back on climate-changing greenhouse gases (GHGs) has been made by many companies, noting that more than 50% of companies surveyed said that efforts they made to preserve water had also led to reductions in GHG emissions.
Some companies performed well on preservation, while others are described as laggards.
“The energy sector is a major laggard and the least transparent about water risks,” CDP reports.
It says 77 of the 109 energy companies surveyed did not provide information about their water risk management policies. These included the giant concerns ExxonMobil, Chevron and Shell.
Morgan Gillespy, head of CDP’s water division, says: “For a long time, companies have taken water for granted as a free and plentiful resource. But these assumptions are unravelling as the impacts of climate change gather pace.
“From the $100 billion-worth of energy infrastructure at risk from rising sea levels in Louisiana to Chinese industry facing tightening restrictions on water use, investors are right to worry about the impacts of water risks on their assets.”
This article was originally published on Climate News Network and is shared under a Creative Commons license. Read the original article here.
Cover photo by Matthew Robey/Flickr (CC by CC by NC-2.0)
Once upon a time (over 2000 years ago), in a land far far away (depends on where you are), the ancient kings of Sri Lanka decided to do something about the water scarcity on their island and built one of the most sophisticated rain harvesting systems of their day and maybe ours.
Sri Lanka, which lies just south of India, has about 80% of its area covered by a dry zone prone to water scarcity. This meant that people would only be able to work their land during the wet season. However, around 300 BC, King Pandukabhaya was the first of many ancient kings to start building a network of water tanks for rain harvesting – a network that still exists today. Canals connect the tanks to large reservoirs. This creates a cascading system that uses the natural topography of the land to collect every drop of rain and distribute it.
After many years of existence and of negligence due to poor understanding of how the system was built and worked, it doesn’t function as effectively anymore which has led to severe problems for many farmers. Now, with the additional pressures resulting from climate change, it is even more important for this water system to be rehabilitated.
That is why the Government of Sri Lanka with the help of UNDP are repairing and upgrading 33 tanks to give self-sufficiency back to farmers and help improve their livelihoods.
Learn more about the work being done, how the tanks work, why they are good for biodiversity, how they mitigate floods and droughts, and more by watching the video below:
Cover photo by Dennis Candy/Flickr (CC by NC-ND-2.0)
Global sea levels have risen by an average of 3.2 mm a year over the past 20 years. Coastal infrastructure such as homes, resorts and roads are under direct threat; as are natural assets such as shallow reefs and beaches. The glacial ice melt that contributes to the sea-level rise phenomenon is likely to continue, however it remains difficult to estimate precise, on-shore repercussions. Current adaptation strategies predominantly focus on total amounts of sea-level rise, however new research suggests that the rate of change may also be an important parameter.
In a 2016 study, the Carnegie Institution for Science modelled how adaptation to ongoing rates of sea-level change enabled planners to determine the optimum distance from the shoreline for future construction.
Building along desirable coastlines is profitable for investors, however buildings in such areas are also exposed to a greater risk of loss and damage. The study suggests that planners should consider both physical and economic factors in their decision making processes. Specifically, the researchers recommend that the rates of change in sea levels (and other environmental factors) and the durability of the built infrastructure should be weighed against near-term profit and long-term costs.
Integrated approaches to resilience building for infrastructure investments are increasingly seen as vital to protect investor capital, and the built environment. The European Commission, for instance, is using an approach developed by Acclimatise and COWI A/S, to integrate climate resilience into the standard project lifecycle appraisal commonly practiced by developers.
The model used for the Carnegie study could have wide reaching implications for important economic sectors. The energy industry, town planning, and asset management are all cited as potential sectors that could benefit.