Category: Climate Change Impacts

Accelerating sea level rise triggered by Antarctic ice melt raises urgent adaptation concerns

Accelerating sea level rise triggered by Antarctic ice melt raises urgent adaptation concerns

By Elisa Jiménez Alonso

As was reported this week, satellites monitoring Antarctica indicated that roughly 200 billion tonnes of its ice are melting each year. The massive ice loss is accelerating sea level rise by about 0.6 millimetres per year – three times more than measured during the last assessment in 2012.

Overall, since 1992 the continent has lost 3 trillion tonnes of ice, enough to raise global seas by 8 millimetres. The researchers responsible for this new assessment say it is “too warm for Antarctica today. It’s about half a degree Celsius warmer than the continent can withstand and it’s melting about five metres of ice from its base each year, and that’s what’s triggering the sea-level contribution that we’re seeing.”

For low-lying coastal communities and cities, this rapid acceleration of sea level rise is troubling news as it is a harsh reminder of how little time there is to prepare for such a daunting challenge. The impacts of sea level rise are manifold, it can lead to coastal erosion, makes storms more dangerous because storm surges lead to flooding more quickly, king tides can flood communities, and for low lying island states it could even mean the loss of their land.

Meaningful and large-scale climate change mitigation could help avoid worst case scenarios. But, with the uncertainty surrounding such actions and the scale at which we could see it implemented in the next years, building resilience to the impacts of sea level rise will be paramount, or rather is already.


Cover photo by Cassie Matias on Unsplash.
Rising heat wave risk looms for Pakistan

Rising heat wave risk looms for Pakistan

By Saleem Shaikh

Average temperatures and heatwave frequency will keep rising in Pakistan, say researchers as the country has struggled to come to grips with soaring temperatures in recent weeks.

A team of international researchers, who say their study is the first to show the country’s heat-wave trajectory forecasts a 75 per cent increase in heat waves by 2030, a 189 per cent by 2060 and a 277 per cent increase by 2090. “This means the country will experience around 12 heat wave events annually by 2030, 20 such events by 2060 and 26 events by 2090,” says Wajid Nasim, lead author and associate professor at the department of environmental sciences, COMSATS Institute of Information Technology.

“Extreme weather events will become more frequent, prolonged and intense” –Wajid Nasim

The study, published this month (June) in Atmospheric Research, shows that Pakistan was hit by 126 heat waves of varying durations over the 1997‒2015 period for an average of seven heat waves per year. This year, at least 65 people have died in the capital Karachi, and temperatures in parts of the country have exceeded 40 degrees Celsius for weeks, reaching a record-breaking 50.2 degrees in April.

These extreme events will become more frequent, prolonged and intense, Wajid tells SciDev.Net.

He and his team relied on historical datasets of heat wave events and daily maximum temperature variations for the study period. The data was drawn from the Pakistan Meteorological Department (PMD) through 29 weather stations in the provinces of Punjab, Sindh and Baluchistan.

Heat waves are defined as spikes in temperature beyond 45 degrees Celsius in the plains, and beyond 40 degrees Celsius in hilly areas. Average maximum temperatures of 42 degrees Celsius, with a 5‒6 degree rise lasting eight days or more, are also classed as heat waves.

The researchers warn that the trend carries risks for crop yields as well as human health. Heat waves raise the irrigation needs of summer crops, increase droughts and contribute to groundwater depletion in the country.

Rising average temperatures during pre-monsoon months (March, April and May), during which most of the heat waves are expected to occur in the coming decades, could lead to early maturity of winter crops including wheat, maize, potato and lentils — and a consequent decline in crop yields.

Higher temperatures during these months will also increase irrigation needs for various summer crops including rice, cotton, sugarcane and mango. A rapid decline in soil moisture and higher levels of surface water evaporation are contributing factors.

Ghulam Rasul, director-general of the PMD, says the findings demand an adaptation response from the government with a focus on early-warning systems.

Rasul observes that March and April used to be cool to mild months, which helped the soil to retain moisture.

“It is startling to observe March becoming warmer every year. The high temperatures we used to record in the peak summer months (June and July) about eight years ago are now being recorded in March,” he tells SciDev.Net.

In June 2015, more than 1,200 people died of heat-related illnesses in the southern port city of Karachi when temperatures soared to 49 degrees Celsius. In May 2010, the city of Mohenjo Daro, also in southern Pakistan recorded 53.5 degrees Celsius, the highest ever recorded in Asia.

Nasim says various adaptation measures, such as building the capacity of individuals and communities to respond to heat stress during heat waves, and campaigns to raise heat-health awareness, are imperative.


This piece was produced by SciDev.Net’s Asia & Pacific desk. This article was originally published on SciDev.Net. Read the original article.

Cover photo by Kamran Ali/Wikimedia (CC BY-SA 3.0): Vegetable and Fruit Market of Layyah at twilight. 2007.
Global warming could be causing tropical storms to ‘slow down and last longer’

Global warming could be causing tropical storms to ‘slow down and last longer’

By Daisy Dunne

Rising global temperatures could be causing tropical storms to slow down, allowing them more time to unleash heavy rainfall once making landfall, a new study suggests.

The research, published in Nature, finds the speed at which they travel across the Earth has slowed by an average of 10% over the past 70 years, with the speed of storms originating in the Western North Pacific falling by 30%.

A “notable example” of this effect was seen during Hurricane Harvey, which “stalled” over Houston, releasing 100cm of rain in just three days, the study author tells Carbon Brief.

Although the new study finds a link between temperature rise and storm slowdown, it is possible that natural climate variability has also played a role in the downturn, the author adds.

However, the new analysis does not consider a range of factors affecting the forward speed of tropical storms, including the time of year and local weather conditions, another scientist tells Carbon Brief.

Slowing storms

Climate change can worsen the intensity of tropical storms (such as hurricanes, typhoons and cyclones) in several ways, including by making record rainfall more likely and by causing sea levels to rise, which can raise the risk of storm surges.

The new research looks at how warming could influence the “translation speed” of tropical storms – the speed at which they move across the Earth.

Storms travel as they are carried along global atmospheric circulation patterns – a worldwide system of winds which transport heat from the equator towards the poles.

Climate change is expected to weaken the world’s circulatory winds, which could, in turn, lead to a slowing of the speed at which tropical storms move forwards, says study author Prof James Kossin, an atmospheric scientist at the National Oceanic and Atmospheric Administration’s (NOAA) Center for Weather and Climate. He tells Carbon Brief:

“Tropical cyclones are moving more slowly over the past 70 years or so. The slowing is seen in every ocean basin, except the Northern Indian Ocean. This is having impacts on local rainfall amounts. It could also be impacting coastal storm surge and wind damage.”

As storms slow, they can last for longer over one area, releasing large amounts of intense rainfall. This could pose a threat if storms stall above areas vulnerable to flooding, such as large urban areas, says Kossin. A “notable example” of this effect occurred during Hurricane Harvey, he says in his research paper:

“The unprecedented rainfall totals associated with the ‘stall’ of Hurricane Harvey over Texas in 2017 provide a notable example of the relationship between regional rainfall amounts and tropical-cyclone translation speed.”

Data deluge

For the study, Kossin analysed tropical storm data taken from NOAA’s International Best Track Archive for Climate Stewardship (IBTrACS). “Best-track data” includes information of tropical storm intensity, position and wind structure. The findings suggest that the forward speed of hurricanes fell by an average of 10% between 1949 and 2016.

However, the change in storm-forward speed varied widely from region to region.

The charts below show changes in storm-forward speed in (from top left to bottom right) the North Atlantic, Western North Pacific, Eastern North Pacific, Northern Indian, Southern Hemisphere (less than 100 degrees longitude) and Southern Hemisphere (more than 100 degrees longitude) over the 70-year period. Changes in speed are shown over land (black line) and sea (dotted line).

Changes to the forward speed of tropical storms from 1949-2016 in (from top left to bottom right) the North Atlantic, Western North Pacific, Eastern North Pacific, Northern Indian, Southern Hemisphere (less than 100 degrees longitude) and Southern Hemisphere (more than 100 degrees longitude) over the 70-year period. Changes in speed are shown over land (black line) and sea (dotted line). Source: Kossin et al. (2018)

The charts show how the largest reductions in speed have occured in the Western North Pacific – where the speed of tropical storms fell by 30% – and the North Atlantic, where speeds fell by 20%. In the Australian region, the speed of tropical storms slowed by 19% – although the statistical significance of this result is “marginal”, Kossin says.

However, storms originating in Eastern North Pacific and Northern India do not appear to have slowed over the study period. This could be down to natural climate factors, such as changing ocean currents, Kossin says.

Human fingerprint?

Although the analysis finds a link between falling storm speed and temperature rise, it does not constitute a “single attribution study”, Kossin notes in his research paper.

Attribution studies attempt to work out to what extent climate change could have influenced the likelihood of an extreme weather event, when other factors, such as natural climate variability, are also considered.

However, this analysis does not attempt to tease apart the impacts of human-caused climate change and natural variability, says Kossin:

“The human-caused factors would be things such as anthropogenic global warming, changes in air pollution, land-use change, ozone depletion, but mostly anthropogenic global warming. The natural factors would be just the internal variability of the planet, for example, naturally varying ocean currents.”

Due to this, it is “far from clear that global climate change has anything to do with the changes being identified” in the study, says Prof Kevin Trenberth, a senior scientist at the National Center for Atmospheric Research (NCAR) in Colorado, who was not involved with the research. He tells Carbon Brief:

“There are some major decadal variations in play. In the Pacific, there is the Pacific Decadal Oscillation.”

The Pacific Decadal Oscillation (PDO) is a recurring climatic event that affects vast areas of the Pacific Ocean. It has “positive” and “negative” phases, which can each last 20-30 years.

Storms on the horizon

The findings provide a “significant scientific advance” in the world’s understanding of how climate change could influence tropical storms, says Dr Shuai Wang, an atmospheric physicist from Imperial College London, who was not involved in the study. He tells Carbon Brief:

“Tropical cyclones are one of Mother Nature’s most devastating hazards. Based on the findings in this article, it is likely – or very likely – that the motion of tropical cyclones has slowed down.”

However, the analysis has not taken into consideration several factors that may have influenced changes to storm-forward speed over the past 70 years, says Trenberth:

“The month of the storm matters. The translation speed is expected to be different in July, September and November. This should have been taken into account. The track and speed of a storm is heavily dependent on the weather patterns in play: the distribution of anticyclones, and cyclones, cold fronts, jet streams, troughs of low pressure and so forth. There is no evidence that these are changing, on the contrary, the expectation even 50 years from now is that the changes will be imperceptible.”


Kossin, J. P. (2018) A global slowdown of tropical-cyclone translation speed, Nature, https://www.nature.com/articles/s41586-018-0158-3

This article was orginally published on Carbon Brief and is shared under a Creative Commons license.

Cover image by David M. Roth/NOAA WPC: Enlarged rainfall graphic for Hurricane Harvey in Southeast Texas.
Urban floods: We can pay now or later

Urban floods: We can pay now or later

By Michael Drescher, University of Waterloo

Wild weather seems increasingly widespread these days. Cities are especially vulnerable to extreme weather, meaning that many of us will end up paying for the damage it can cause.

But how much we pay — and when — is largely up to us. We could, for example, pay now to prepare ourselves and limit future damage, or we can pay later to repair our properties and restore the environment.

Urban flooding — and other complex, environmental challenges — can be solved when communities work together to share their experiences and knowledge. In Canada, the Faculty of Environment at the University of Waterloo is taking the lead on this as part of the UN Sustainable Development Solutions Network.

Urban floods on the rise

Many factors contribute to the increasing risk of flooding in urban areas. For one, in many regions climate change seems to be causing more intense downpours than what have occurred in the past.

This is a problem because the storm-water systems built just a generation ago were not designed to handle the amounts of rain we are seeing now — and expecting in the future.

The growth of cities also contributes to urban flood risk. The increased construction of hard, sealed surfaces hinders rain from soaking into the soil and causes runoff. If there is too much runoff, the water pools and enters our lakes and rivers, dragging oil, metals, road salt or pesticides with it.

Or it can turn into a flood.

The density of sealed ground continues to grow in urban areas. We just keep on adding more houses, more roads, more parking lots. From 1991 to 2011, the built-up urban area in major Canadian cities increased by more than 20 per cent.

On top of that, houses are being built closer together and they get ever bigger. More than half of the homes built after 2001 are larger than 140 square metres. When you factor in that these new homes come with patios, parking pads, driveways and sidewalks, it’s no wonder we have a problem.

Level of preparedness

Unfortunately, city dwellers, by and large, are not well-prepared for urban floods. A recent study found that most people do not know if they are living in flood-prone areas and, if they do, many do not take measures to protect themselves against flooding.

They may not know that many home insurance policies do not cover water damage from flooding, but only damage from broken pipes or similar issues. Or if the policies do cover flood damage, that the coverage might be limited.

And governments may refuse to bail house owners out, so to speak, if they could have purchased insurance add-ons that do cover flood damage.

Even so, most municipalities do not address the issue of urban floods as effectively as they could — maybe because their budgets are too strained to act or they have other, seemingly more pressing, priorities.

Recently, flooded-out residents in Ontario have filed lawsuits against their municipalities, and a few years ago in Illinois, a major insurance company filed nine class action lawsuits against municipalities over this.

How can homeowners prepare?

It is not a question of whether wild weather will affect your neighbourhood, but when. Somebody will pay for it — and it might be you.

You could pay upfront to protect yourself against damage or afterwards to fix it. There are a number of things that people can do to protect their homes, their neighbourhoods and the environment against the damages caused by urban floods:

  1. Purchase add-on flood protection with your home insurance.
  2. Keep the water from getting in. Covers can prevent water from rushing in through basement window wells, and foundation grading can direct surface water away from your house. You could also install a sump pump or sewer backflow prevention system.
  3. Install on-site water storage to collect and store rainwater for safe release later. Some municipalities sell rain barrels; larger water storage tanks are even better.
  4. Green infrastructure solutions can slow down rainwater runoff and help the ground soak up the water. Rain gardens — specifically designed depressions with plants for increased water infiltration — and green roofs are options. Patios and driveways can be built with permeable pavements.
  5. Talk to your neighbours, your neighbourhood association and your city councillor about urban floods. These strategies work best when many people in a neighbourhood take action together.

Change can be expensive, but municipalities are increasingly providing tax incentives or financial assistance to pay for some of them.

Nothing will provide 100 per cent protection against the potential losses from urban floods, but planning ahead reduces the odds that you will be flooded and may reduce your costs when a flood does occur.

The ConversationThe neat thing is that by acting with foresight and heeding this advice, we can protect ourselves, protect our neighbours and protect the environment, all at the same time.


Michael Drescher, Associate Professor, University of Waterloo. This article was originally published on The Conversation. Read the original article.

Cover photo by Fred/flickr (CC BY-SA): Flood waters rise in the Montreal neighbourhood of Cartierville in May 2017.
NOAA Hurricane Season Forecast 2018: 75% chance of near or above normal season

NOAA Hurricane Season Forecast 2018: 75% chance of near or above normal season

By Elisa Jiménez Alonso

Forecasters from the National Oceanic and Atmospheric Administration’s (NOAA) Climate Prediction Centre (CPC) predict a 35 per cent chance of an above-normal season, a 40 per cent chance of a near-normal season, and a 25 per cent chance of a below-normal season for the upcoming Atlantic hurricane season, which extends from June 1 to November 30. Prior to the peak of the season, in early August, NOAA will provide an update to this outlook.

In terms of storms, this means that there is a 70 per cent chance of 10 to 16 named storms (winds of 63 km/h or higher) forming, of which 5 to 9 could become hurricanes (winds of 120 km/h or higher), including 1 to 4 major hurricanes (category 3, 4 or 5; with winds of 179 km/h or higher). For context, average hurricane seasons tend to produce 12 named storms, of which 6 become hurricanes, which includes 3 major hurricanes.

Two of the main factors driving this outlook are the possibility of a weak El Niño developing and near-average seas surface temperatures in the Atlantic Ocean and Caribbean Sea. However, both of these factors are also influenced by atmospheric and oceanic conditions that are conducive to hurricane development and have been producing stronger hurricane seasons since 1995.

Hurricane track and intensity forecasts are incredibly important for risk management and preparedness. After 2017’s devastating Atlantic hurricane season, many communities, especially in the Caribbean, still find themselves in very vulnerable situations.


Listen to our latest podcast with Angela Burnett, author of the Irma Diaries, who witnessed Hurricane Irma first hand and collected survivor stories from the British Virgin Islands to shed light on the urgency of building back better and building resilience:

Cover photo by NOAA: NOAA’s GOES-16 satellite (now GOES-East) captured this infrared/visible image of Hurricane Harvey on August 25, 2017.
Low awareness of climate risks hampering resilience of critical infrastructure sectors claims new study

Low awareness of climate risks hampering resilience of critical infrastructure sectors claims new study

Low levels of awareness of climate risks and the availability of climate services are significant barriers to climate adaptation in the electricity sector, according to new research from Germany. However, the research also finds that the underlying market opportunity for climate services remains strong.

Damage to a critical infrastructure, its destruction or disruption by for example natural disasters, will have a significant negative impact on the security of the EU and the well-being of its citizens. Focussing on the German electricity sector, the report found that stakeholders in the sector claimed to need seasonal forecasts and decadal predictions, the latter aligning closely with energy companies’ time frames for strategic planning. However, despite this, there is currently a low level of demand for climate services from the sector.

The report found that four major barriers prevented the uptake of climate services:

  1. low awareness of the climate-related risks,
  2. low awareness of the benefits climate services can provide,
  3. mismatches between the required and the available timescales and spatial resolution of data and
  4. a lack of trust in the reliability of data.

In order to overcome these hurdles, the report recommends that considerable work needs to be done in the first instance to increase the visibility of the climate services industry and how it can contribute to the climate resilience of key sectors. It proposes that a ‘Climate Service Provider Store’ is created to provide information about where appropriate climate service providers are available.

Additionally, the case study recommends that work continues to ensure that seasonal and decadal forecast become ever-more accurate and that regional cooperation between industry networks and climate services providers are strengthened.

The case study was led by the non-profit research organization HZG under the MArket Research for a Climate Services Observatory (MARCO) programme of which Acclimatise is a proud partner. MARCO, a 2-year project coordinated by European Climate-KIC, hopes that research such as this will help to remove the barriers to the growth of the climate services industry across Europe.


Download the full case study “Critical Energy Infrastructureshere.

Download an infographic highlighting the key findings of the case study here.

Cover photo from pxhere (public domain).
Podcast: Hurricane Irma: Angela Burnett, author of The Irma Diaries

Podcast: Hurricane Irma: Angela Burnett, author of The Irma Diaries

In 2017 the Caribbean was struck by a series of hurricanes, the largest of which, hurricane Irma, was the strongest open Atlantic storm on record. Irma’s peak wind speeds reached 180mph as it caused catastrophic damage to the islands of Barbuda, Saint Barthelemy, Saint Martin, Anguilla and the Virgin Islands.

Today we hear from someone who experienced the full force of Irma first-hand. Angela Burnett, a lifelong resident of the British Virgin Islands was working as the territory’s climate change officer when Irma struck, but even having experienced severe hurricanes in the past, she was deeply affected by the storm.

To draw attention to those living, as she does, on the front lines of climate change, Angela embarked on a mission to tell the stories of the survivors and how it has changed them.

After a process that saw Angela work late into the night by candlelight, make clandestine trips to write at a local sewage treatment works and face armed police barricades, Angela’s book ‘The Irma Diaries: Compelling Survivor Stories from the British Virgin Islands‘ was born. This is her story.


The Irma Diaries is available to purchase here.

Learn more about the book and hear extracts from the survivors’ stories here.

Cover photo by DFID/Flickr (CC BY 2.0): Damage caused by Hurricane Irma in Road Town, on the British Virgin Island of Tortola, 12 September 2017.
Record heat means hurricanes gain ferocity faster

Record heat means hurricanes gain ferocity faster

By Tim Radford

Hurricane forces are accelerating, and devastating floods can be linked to warmer oceans. But climate change is not the only factor. Hurricanes are becoming more violent, more rapidly, than they did 30 years ago. The cause may be entirely natural, scientists say.

But Hurricane Harvey, which in 2017 assaulted the Gulf of Mexico and dumped unprecedented quantities of rain to cause devastating floods in Texas, happened because the waters of the Gulf were warmer than at any time on record. And they were warmer because of human-driven climate change, according to a second study.

Both studies examine the intricate machinery of a natural phenomenon, the tropical cyclone. Researchers from the Pacific Northwest National Laboratory looked at how fast four of 2017’s hurricanes – Harvey, Irma, Jose and Maria – intensified: episodes in which maximum wind speed rose by at least 25 knots, which is more than 46 kilometres per hour, within a 24-hour period. They report in Geophysical Research Letters that they combed through 30 years of satellite data from 1986 to 2015 to find a pattern.

“As climate change continues, we can expect more supercharged storms like Harvey”

Researchers have repeatedly warned that hurricane hazard must increase with global warming, driven by profligate human combustion of fossil fuels that dump greenhouse gases in the atmosphere. Hurricanes will hit higher latitudes and deliver more damage within the Gulf of Mexico. But climate change is only part of the answer.

The latest study did not find that storms were intensifying rapidly more often than usual. But the researchers did find that when a storm grew at speed, it became much more powerful within a 24-hour period than such storms did 30 years ago: wind speeds had gained 3.8 knots or seven kilometres an hour for each of the three decades.

And although hurricanes are driven by the warmth of the upper ocean, the researchers decided that rather than overall ocean warming, in this case the biggest factor was a natural cycle called the Atlantic Multidecadal Oscillation, which in its present phase tends to make ocean waters warmer in the central and eastern Atlantic – the spawning ground for Irma, Jose and Maria.

Warmest on record

But when Harvey hammered the Texas coast in August 2017, the waters of the Gulf of Mexico were warmer than they had ever been. And scientists from the National Center for Atmospheric Research (NCAR) report in the journal Earth’s Future that they calculated the rate of evaporation as the hurricane winds raced over the water and compared it with the levels of precipitation over the city of Houston.

To make a hurricane happen at all, ocean temperatures need to reach 26°C. When Harvey gathered its strength and its moisture, the Gulf waters had tipped 30°C.

“We show, for the first time, that the volume of rain over land corresponds to the amount of water evaporated from the unusually warm ocean,” said Kevin Trenberth, a senior scientist with NCAR. “As climate change continues, we can expect more supercharged storms like Harvey.”


This article was originally published on Climate News Network.

Cover photo by NASA (CC BY 2.0): Hurricane Matthew Hits Haiti.
Alaskan town threatened by climate change gets federal funding for relocation

Alaskan town threatened by climate change gets federal funding for relocation

By Elisa Jiménez Alonso

Newtok, a small Alaskan village on the shores of the Ningliq River, has been fighting erosion exacerbated by climate change for decades. Now, they have secured $15 million to begin relocating houses to higher ground.

The people of Newtok have been trying to relocate since 1994 with little to no success. In recent years, the effects of climate change have made the village’s situation increasingly urgent and dire. Currently, the river is creeping 70 feet closer every year.

In its efforts to secure funding, Newtok’s main problem was that no federal agency seemed to be responsible for the somewhat unusual predicament creating a barrier to access funding. From federal disaster relief funds to the Department of Housing and Development – no one seemed to cover the particular needs of Newtok.

Earlier this year, the Alaska Denali Commission, an independent federal agency designed to provide critical utilities, infrastructure and economic support throughout Alaska, saw its fairly tiny budget doubled to $30 million as part of the $1.3 trillion spending bill signed in late March.

Half of the allocated budget will be spent on Newtok’s relocation. However, $15 million only cover a fraction of the necessary funds. In a 2006 report, the US Army Corps of Engineers calculated Newtok would need between $80-130 million to relocate and had about 10-15 years left to do so.

Twelve years later, the allocated budget is at least a start and the Denali Commission is ready to get to work. They want to have “as many occupiable housing units as possible in place by October 1, 2019.”

A further smaller grant of $1.7 million was also announced; it is funded by both the state and the Federal Emergency Management Agency (FEMA). The grant comes as part of FEMA’s Hazard Mitigation Grant Program which is reserved for “traditional” disasters but the urgency of Newtok’s situation made it necessary to provide funds.


To learn more about the history of Newtok, click here.

Cover photo by mariahb.rm/Flickr (CC BY 2.0): Aerial shot of Newtok.

Read more about Newtok on the Acclimatise Network:

Arctic communities: between adaptive capacity and adaptation action

Video: Climate change swallows an Alaskan school

Alaskan village hit by erosion and melting permafrost is denied request for disaster declaration

 

3°C may double Europe’s drought risk

3°C may double Europe’s drought risk

By Tim Radford

The big heat is on the way. As the world warms, so will Europe’s drought risk, and its soils will turn increasingly dry.

If average global temperatures rise by just 3°C, then Europe’s drought risk could increase to  double the area faced with drying out. Right now, just 13% of the continent can be counted as a drought-prone region. As the thermometer soars, this proportion could rise to 26%.

And 400 million people could feel the heat as the water content in the European soils begins to evaporate. The worst droughts will last three to four times longer than they did in the last decades of the last century.

The number of months of drought in southern Europe could increase significantly. In this zone drought is already measured over 28% of the land area: this could, in the most extreme scenario, expand to 49%.

Iberian extreme

“In the event of a three-degree warming, we assume there will be 5.6 drought months per year; up to now, the number has been 2.1 months. For some parts of the Iberian peninsula, we project that the drought could even last more than seven months,” said Luis Samaniego, of the UFZ Helmholtz Centre for Environmental Research in Germany.

His co-author Stephan Thober added: “A three-degree temperature rise also means that the water content in the soil would decline by 35 millimetres up to a depth of two metres. In other words, 35,000 cubic metres of water will no longer be available per square kilometre of land.”

The two scientists, with colleagues from the UK, the US, the Netherlands and Czechoslovakia, report in Nature Climate Change that they used mathematical models to simulate the effect of temperature rise as a response to ever-greater global emissions of greenhouse gases into the atmosphere, from the combustion of fossil fuels.

The 35mm loss of water was roughly what parts of Europe experienced during the unprecedented drought of 2003. If planetary temperatures do rise by 3°C, then such episodes could become the normal state in many parts of Europe, and far worse could be on the way.

“In the event of a three-degree warming, we assume there will be 5.6 drought months per year; up to now, the number has been 2.1 months”

Once again, none of this will come as a shock to other climate scientists, who have repeatedly warned that the cost of not confronting the menace of climate change could be huge in terms of lives lost, forests burned and harvests ruined.

Europe’s cities could become uncomfortably and even potentially lethally hot, and the southern nations of the Mediterranean could face devastating heat and drought.

But such droughts are not inevitable, nor likely across the whole of Europe. The Baltic states and Scandinavia could experience higher rainfall in a warmer world. The same simulations found that – were the world to achieve the 1.5°C global warming limit which 195 nations agreed upon at the Paris climate summit in 2015 – then the Mediterranean region would experience only 3.2 months of drought. And water loss in the top two metres would be only about 8 millimetres.


This article originally appeared on Climate News Network.

Cover photo by Rodelar/Wikimedia Commons (CC BY-SA 4.0): Dry fields in León, Spain, during the 2017 drought.