Category: Water

Cape Town climate conference kicks off in wake of water crisis

Cape Town climate conference kicks off in wake of water crisis

By Georgina Wade

This week, a major international climate change conference takes place in a city that is dealing with one of the most severe water crises in its history. The Adaptation Futures conference, taking place in Cape Town, South Africa, will host delegates from around the world to discuss how the world can better prepare for climate change and its impacts. The conference has put in place measures to reduce its water demand, but in doing so it has also highlighted the severe inequality in both access to water, and in the ability to adapt to a lack of it.

An El-Niño-triggered drought struck the Western Cape province of South Africa in 2015, resulting in a severe water shortage in the city of Cape Town and the surrounding region. At the start of this year, April 2018 was announced by the government as “day zero” – a moment when dam levels would be so low that they would turn off the taps in the city and send people to communal water collection points. The water shortages are shining a light on South Africa’s already high-income inequality. South Africa has a long history of social inequity, and to this day 10 percent of the population own more than 90% of the country’s wealth.

With the current water consumption limit set at 50 litres per person, surges of spending on personal efforts to counteract the limited water supply are on the rise amongst wealthier residents. One such method is through the installation of a borehole which works by tapping into underwater reservoirs.

Borehole installation in the backyards of the wealthier Cape Town suburbs currently costs anywhere from $6,000 USD, with high demand resulting in a waiting list of requests that can take up to 7 months to fulfil. While borehole use is legal, Level 6b water restrictions currently prohibit the use of borehole water for outdoor purposes and requires that all water use be metered and recorded for availability upon inspection. Additionally, machines that turn moisture into drinking water are costing residents around $2,000 USD per installation. “The lesson here is that you can’t trust the government to provide water for you,” said Gabby De Wet, whose family owns De Wet’s Wellpoints and Boreholes. But where does this leave those that can’t afford to prepare for the worst?

With residents scrambling to find their own private solutions, the availability of options truly boils down to monetary income. And for the poor, it means waiting to see what solutions the government comes up with while contemplating what cuts can be made to weekly food intake in order to buy bottled water.

Although water conservation efforts have pushed back “Day Zero” to 2019, informal settlements on the outskirts of the city are still struggling to obtain clean water to meet their daily needs. For many residents of the city’s low-income townships, water has always been a rare commodity. In Cape Town’s largest township, Khayelitsha, it is estimated that around 1.2 million people live in informal housing, relying on communal toilets and drawing water from communal standpipes.

Wealthier residents still use more water

Some say poorer residents are unfairly blamed for overuse of water resources, as concerns rise over water waste. After exploring the distribution of water usage, the Associated Press found that most of the misuse can be attributed to those of the wealthier class. According to water experts, the Cape Town’s poor townships make up 25 percent of the city’s 4 million people yet only use 4.5 percent of the water.

“It has been in the areas where people have gardens and swimming pools,” Kirsty Carden of Future Water Institute said. “They are much more profligate in the way that they use water, because they’re used to the water just coming out of the taps.”

Cape Town’s economy relies heavily on business and event tourism with the city recently crowned by the International Congress and Convention Association (ICCA) as the number one city in Africa for business tourism events. Given that tourism supports an estimated 300,000 jobs in South Africa’s Wester Cape province, visitors avoiding Cape Town due to water shortages would have a significant impact on peoples’ livelihoods.

While additional population pressure from tourists may increase water demand slightly, research suggests that international visitors to Cape Town add a maximum of 1% to the local population during the peak summer season. With short-term and relatively moderate water needs compared to other water consumers, the $3.4 billion economic contribution tourism provides to the province holds a significantly positive impact to Cape Town and the thousands of households it supports.

A climate conference in the midst of a climate crisis

Adaptation Futures 2018 aims to facilitate dialogues for solutions between key actors from diverse perspectives and regions on adaptation efforts linked to sustainable development, investment and planning. With a strong focus on Africa and the Global South, the conference aims to use the Cape Town setting to foreground developing country adaptation issues.

Acknowledging the significant ecological and carbon footprints conferences inevitably have, the organisers have outlined and established methods towards reducing impacts in an effort to ‘green the conference’.

“The organisers of Adaptation Futures 2018 are actively planning to reduce or offset the conference footprint as much as possible,” the website states. “Minimising the conference footprint depends on every single participant and we count on everyone to make this conference notably and visibly environmentally friendly in both word and action.”

The conference venue, the Cape Town International Convention Centre (CTICC), has decreased its use of municipal water through rain water harvesting tanks and its own desalination unit, as well as using bottled water for all culinary purposes. Additionally, the CTICC has aligned all its sustainability efforts and commitments with Global Reporting Initiative (GRI) standards.

The CTICC’s 65,000 litres of rain water storage tanks allow for the reuse of water for all cleaning and maintenance activities inside the centre. Furthermore, the implementation of air-cooling systems that create water from air will allow for the storage of water in the available 10,000 litres of grey water storage tanks. With a recorded 42% saving in water consumption for the first quarter of its current financial year compared to the same period last year, the CTICC’s focus remains on reducing water usage wherever possible and ensuring their events run successfully in a responsible manner.

Each delegate will be expected to adhere to the water restriction of 50 litres per person per day and will be provided with a durable water bottle to be refilled at designated water points. For the 200,000 litres of water expected to be used by 1,000 delegates, Adaptation Futures 2018 will compensate by donating rain water harvesting tanks to a local project that will reduce future municipal consumption.

Emphasising that an offset is not a license to use more water, Adaptation Futures is encouraging all of its delegates to adhere to the stipulated level 6b water restrictions. Additionally, the city of Cape Town will be hosting two sessions on urban water scarcity and delegates will be invited to contribute potential adaptation solutions.

Perpetuating inequality?

While some have raised questions about whether Adaptation Futures should have been moved from Cape Town so as to relieve pressure on water resources, others make the point that the event has an opportunity to bring global attention to climate risks. There is no doubt that the conference has been proactive in reducing the impact of its own water use, however has it done enough to reduce the problem of water inequality in the city?

Hotels in the area are now taking steps to decrease reliance on municipal water supply. South Africa’s biggest hotel group, Tsogo Hotel Holdings, is even building a desalination plant that will help supply its Cape Town hotel with their own water, as well as provide alternative water augmentation. The new plant, will use a considerable amount of energy to produce potable water for some of the wealthiest of Cape Town’s visitors. It risks becoming a totem of water inequality in the city.

Although Adaptation Futures claims it will be supporting a worthy project that reduces municipal water consumption and increases off grid water usage, the details of this project have yet to be published and may not be created in the interest of benefiting the poorer neighbourhoods. Rather than focusing minds on delivering enough water to the city’s central business district, Adaptation Futures should use this opportunity to help finance water efficiency and supply projects that benefit some of these more water-vulnerable communities. Water scarcity will be front of mind for many of the delegates to the conference; to provide city-wide solutions to future climate scarcity, the inequality of the residents’ capacity and capability to take adaptation action must also be a primary consideration.


Acclimatise will be presenting a number of sessions at Adaptation Futures 2018. Our team members John Firth, Laura Canevari, and Virginie Fayolle will be at the conference. Find out where you can meet them by clicking here.

Cover photograph by Mike Peel/Wikimedia Commons (CC-BY-SA-4.0): Reservoir in Cape Town, view from Signal Hill, taken on 12 June 2014.
Morocco heads for a thirsty future

Morocco heads for a thirsty future

By Kieran Cooke

Despite ambitious efforts to cope with the effects of water shortage and climate change, Morocco faces a dauntingly dry century.

Morocco, host of the 2016 United Nations conference on climate change, is facing a number of problems associated with global warming, including ever-increasing water shortages.

In recent years drought in what is one of the most water-stressed regions of the world has caused severe damage to the economies of Morocco and neighbouring North African states.

In 2015/2016 a prolonged drought caused Morocco’s production of grain to plummet by more than 70%. In 2017 water shortages became acute and the King of Morocco, Muhammed VI, issued a decree calling on the faithful at mosques throughout the country to pray for rain.

The droughts have led to social unrest in what till now has been considered one of the more politically stable countries in the region.

“Higher temperatures, less rainfall and increased land salinity in a country that is already suffering from insufficient water resources do not augur well for the future of agriculture”

Protests over what has been seen as government inaction and incompetence have broken out in several areas; in November last year 15 people were crushed to death as hungry farming families queued for supplies of flour.

A bad situation looks likely to become worse. Latest research by the Brookings Institution in the US predicts that climate change is going to result in average temperatures rising across the North African region by 3°C by 2050.

Rainfall over much of Morocco is expected to decline by 10% at the same time as water usage rates rise substantially.

“Higher temperatures, less rainfall and increased land salinity in a country that is already suffering from insufficient water resources do not augur well for the future of agriculture, unless urgent action is taken now,” says the Brookings research.

Expanding Sahara

There is also concern that, along with warming, the Sahara desert could advance northwards, further threatening Morocco’s important agricultural sector, which accounts for 15% of gross domestic product (GDP) and employs 40% of the country’s workforce.

To meet the challenges of climate change and water shortages the government has brought in its Plan Maroc Vert.

The plan includes an ambitious renewable energy programme, with a target of producing more than 50% of electricity supply by 2030 through a combination of solar and wind power.

Near the town of Ouarzazate, on the edge of the Sahara desert, Morocco is building what’s billed as one of the world’s biggest solar installations.

Need for basics

To cope with water shortages the government is also constructing what is likely to be the world’s largest desalination plant – turning seawater into drinking water – near the tourist destination of Agadir on Morocco’s Atlantic coast.

Officials have also promised to spend millions promoting more efficient irrigation systems, and they are encouraging farmers to plant fruit trees rather than water-hungry cereal crops in an effort to promote water conservation and prevent further soil erosion.

Critics say the government’s approach is half-hearted: they say too much is being spent on mega-projects such as high-speed railways and constructing what will be Africa’s tallest building, rather than repairing and expanding basic infrastructure.

Social Watch, an international network of citizens’ organisations fighting poverty around the world, says 35% of Morocco’s water is lost through bad piping. Water is also polluted by industrial and urban waste.


Cover photo by Anes El bardoudi on Unsplash.
New approach puts theory of Climate-Resilient Water Management into practice on the ground

New approach puts theory of Climate-Resilient Water Management into practice on the ground

South Asia has 23.7% of the global population but only 4.6% of the world’s renewable water sources. Countries in the region already face considerable water management challenges due to high population density, poverty, and a high dependence on agriculture as a source of livelihood. Water resources in South Asia are overexploited and depleting fast, and institutions are struggling to manage and allocate water effectively. Climate change will only exacerbate existing problems through irregular rainfall patterns and increased incidence of floods and droughts.

Since 2014 the Action on Climate Today (ACT) programme has been actively working in five South Asian countries – Afghanistan, Bangladesh, India, Nepal and Pakistan – to help national and sub-national governments plan for, and manage, the impacts of climate change in the water sector. The ACT programme has championed a Climate-Resilient Water Management (CRWM) approach as a way of increasing the resilience of water systems on which billions of people rely.  The programme’s activities in this domain range from preparing urban flood management plans and adapting agriculture to increasing incidences to drought, to mainstreaming climate adaptation in water policies and estimating the future demand for water under different climate scenarios.

This framework is informed by these activities and within this water management interventions are sorted into three categories:

  1. Water resource management (including assessment, supply augmentation and demand management);
  2. Management of extreme events (floods and droughts); and,
  3. Creating an enabling environment for CRWM (including mainstreaming climate impacts in sectoral and cross-sectoral policies, among other governance instruments).

The framework distinguishes CRWM activities as different from conventional water management because they have to adhere to three main criteria:

  1. The best available climate information and data have to be used to go beyond business as usual;
  2. The principles of resilience, such as using ‘buffers’ and having flexibility and adaptability are systematically integrated; and,
  3. A sharp focus on reducing the vulnerability of poor and marginalised communities.

Government officials are already aware of unseasonal, more intense and frequent, instances of drought, monsoon rains and floods, and urgently seek ways to address the impacts citizens face. This presents an opportunity and entry point to engage policy makers in the CRWM process.


The full ACT learning paper “Climate-Resilient Water Management: An operational framework from South Asia” and a learning brief can be accessed here: http://www.acclimatise.uk.com/collaborations/action-on-climate-today/#ui-id-7

Listen to a 60-second audio abstract of the paper:

ACT (Action on Climate Today) is an initiative funded with UK aid from the UK government and managed by Oxford Policy Management (OPM).

Key Contacts

Cover photo by Milaap.org/Flickr (CC BY 2.0).
Tokyo’s massive flood protection facility might not be “enough” due to climate change

Tokyo’s massive flood protection facility might not be “enough” due to climate change

By Elisa Jiménez Alonso

In Tokyo, an enormous underground flood protection system pumps excess water out of the metropolitan area into the sea and has reduced flood occurrences massively. But, climate change might take it to its limits.

When you look at a photograph of the Metropolitan Area Outer Underground Discharge Channel, or G-Cans, you might be reminded of J.R.R. Tolkien’s Mines of Moria and the terrifying Balrog that lived there. However, it is the world’s largest underground flood water diversion infrastructure, built on the outskirts of Tokyo.

The numbers associated with this cavernous super structure are truly impressive: 50 metres beneath the surface, five containment silos, each 65 metres high and with a diameter of 32 metres, are connected by a 6.3-kilometre network of tunnels. The silos are so big, they could fit the Statue of Liberty inside. The structure also has a large cistern, the “Underground Temple”, 18 metres high, 78 metres wide, and 177 metres long with 59 massive pillars and connected to the drainage facility of the system which consists of 4 pumps that can pump a total of 200 cubic metres of water per second.

Concept drawing of G-Cans. Source: Edo River Office, Kanto Regional Development Bureau, Ministry of Land, Infrastructure, Transportation, and Tourism.

The underground system was built in 2006 and cost roughly $2 billion. Now, climate change threatens to erode the capacity thresholds of G-Cans. According to the Japanese Meteorological Agency, Japan, already one of the wettest areas of the world, will see even more rainfall. Additionally, sea level rise is threatening Tokyo, which is further exacerbated by subsidence. In 2015, heavy rainfall caused by a typhoon filled Tokyo’s flood protection system with almost 19 million cubic metres of water – which could roughly fill 7600 Olympic size pools – and took four days to be pumped out.

For the time being, the facility remains crucial to Tokyo’s flood defences. However, in the face of climate change and possibly looking at a future where this structure alone will not be able to protect Tokyo’s 38 million inhabitants from floods, Nobuyuki Tsuchiya, former chief civil engineer of Tokyo’s Edogawa ward, said to the New Statesman that current flood protection measures “are not enough.” Kuniharu Abe, who heads the Metropolitan Area Outer Underground Discharge Channel, further adds he is “not sure Japan can build something like this again.”

It begs the question if attempting another infrastructure project of such enormous proportions (literally and financially) even is the correct way forward. Concrete defences often offer a very obvious and visible form of flood protection and can attract more people to flood-prone areas. This is what happened to Saitama, where the G-Cans facility has reduced floods significantly. Many businesses settled in the area and might face a future when frequent flooding returns.

It is important to emphasise that the Metropolitan Area Outer Underground Discharge Channel is by no means a story of failure, it has already avoided many floods and will, at the very least, continue to alleviate them in the future. But it tells a story about the fact that adaptation to increasing flood risk, or any climate risk for that matter, is never one-dimensional. No single project will remove the risk. It is important to consider many aspects from infrastructural solutions, zoning and land use, to public risk awareness and preparedness.


Cover photo by Kunitaka NIIDATE/Wikimedia Commons: Metropolitan Area Outer Underground Discharge Channel Kasukabe, Saitama, Japan
Workshop: Hydrological Services for Business

Workshop: Hydrological Services for Business

This workshop, co-organised by ECMWF, the Copernicus Emergency Management Service and the University of Reading, is a unique opportunity for global businesses to meet the Global Flood Awareness System (GloFAS) development team and influence the future shape of its hydrological services and forecasting products.

The event will take place 8-9 May 2018 in Reading, UK. Pre-registration (required) is open until 6 April 2018. Acceptance notifications will be sent to attendees by 13 April 2018.

About GloFAS

The Global Flood Awareness System is a hydrological service, currently providing global overviews of upcoming flood events (up to 30 days ahead) and of high and low flow (up to 4 months ahead) in rivers across the world. GloFAS has over 1,600 registered users and its forecasts are freely available to all users.

Objectives

  • Introduce GloFAS services and products to the global business community
  • Provide a networking opportunity between a global hydrological forecasting service provider and the business sector
  • Identify and prioritise global business needs in terms of hydrological products and services
  • Draft a future development strategy for GloFAS with these needs in mind
  • Establish a community of users of hydrological services from the business sector
  • Provide GloFAS training and best practice

Agenda

Main workshop 8 May 2pm– to 9 May 1pm

  • Introduction to GloFAS
  • Real-life case studies from guest speakers
  • Structured activities to discover and prioritise future service provision
  • Ignite talks and market place for business promotion

Optional 9 May 2–4pm

  • GloFAS training session

Background

Floods and droughts are some of the most challenging environmental hazards. In 2017, their combined cost worldwide is thought to have reached more than $50bn.

In a global economy and interconnected world, local hazards can have global impacts on business, including service disruption (supply, production and distribution), variable expenditure (commodity price, damage costs, premiums) and changes in market value (production and demand).

Access to reliable reanalyses and forecasts of hydrological extremes could enable businesses to put in place measures to mitigate anticipated impacts whilst capitalising on potential opportunities.

Thanks to recent computational, scientific and technological advances, this is now possible. With skillful predictions of global weather patterns up to several weeks in advance, and the use of global hydrological models, flood and drought events can be predicted, and it is possible to anticipate where and when the flow in rivers will be higher or lower than usual.

For further details visit the event website or email: events@ecmwf.int

Download the workshop leaflet by clicking here.

 

Citizens unite in Cape Town’s water crisis

Citizens unite in Cape Town’s water crisis

By Leonie Joubert

With Cape Town’s water crisis so bad that its taps may soon run dry, Capetonians are working together to avert a shared disaster. The people of this city are preparing for Day Zero – a water shortage expected four months from now as Cape Town’s water crisis intensifies, likely to be so severe that the reservoirs will be virtually empty.

It sounds like a grim prospect. If it happens, it probably will be. But the good news is that across the city, regardless of differences of wealth and class, South Africans are working together to try to ensure that Day Zero never dawns.

São Paulo, Melbourne and Cape Town are three cities with one thing in common: they’ve all recently faced critical water shortages. Swelling populations, water infrastructure upgrades that aren’t keeping pace, and severe drought are on a collision course to become an urban manager’s worst nightmare, with fresh water and sanitation systems threatening to run dry – literally.

As climate change continues to ratchet up around the world, making rain patterns less predictable, and heatwaves and droughts harsher and stronger, many more cities will face similar intersecting challenges in future.

Surprising co-operation

But a study of water use behaviour amongst Cape Town residents over the past three years shows surprising levels of co-operation around efforts to conserve the city’s “common pool resource”, its municipal water reserves. And the story is one which belies the media reports that people are selfishly panic-hoarding ahead of the prospect of the water being turned off to most of the city.

This February, Cape Town announced the possible arrival of Day Zero, an emergency response measure that the city says it will put in place, should the dams run down to their last remaining 13.5% of available water.

To conserve the dams’ final dregs, the city says it will shut off water to homes and businesses, and trickle-feed the remaining reserves through to critical services like hospitals. Residents will have to queue at communal water distribution points around the city to get a daily ration of 25 litres of water.

Media reports immediately said residents of the city appeared to be panic-buying bottled water and installing bulk water storage tanks.

Pulling together

The concern was that those who had the means to install these tanks would fill them from the municipal water system, to stock up ahead of Day Zero. This would mean vastly exceeding their current daily ration of 50 litres of water per person per day, and would result in a hefty fine or higher water bills.

But a recent analysis by a behavioural economist at the University of Cape Town (UCT) shows that Capetonians’ behaviour has actually been the opposite: that they have been pulling together in the past few years, in response to various measures by the city to get people to reduce their water use.

Martine Visser, from UCT’s Environmental Policy Research Unit, has been tracking water use behaviour amongst Cape Town’s residents, to see how effective various measures by the city have been in getting people to change their behaviour: media education campaigns, dramatic tariff increases, daily limit restrictions and fines for those who break the restrictions – and a few more.

Looking at 400,000 homes across the city, Visser and her colleagues saw an overall decrease in household water use of nearly 50% in just three years, dropping from 540 litres per household per day in January 2015 to 280 litres in January 2018.

“The worst possible outcome right now would be if people lost faith in each other’s ability to safeguard the remaining water”

It took drought-crippled Melbourne a decade to reduce residential water use by 40% from 2000 to 2010 during Australia’s “millennium drought”. In California similar water behaviour measures resulted in a per person reduction of 63% – from 1995 to 2016.

Most interesting in the analysis, says Visser, is the fact that wealthier Capetonians are doing their bit. Since the height of summer 2015 the richest households have cut their water use to that of the lowest income households, who have much less scope to reduce their water consumption further.

This dramatic drop is partly explained by the fact that wealthier families can in fact afford to invest in drilling boreholes or wells and installing bulk water storage tanks, which have helped reduce demand on the municipal supply. But it is also a consequence of sharp water reduction efforts by individuals.

Together, this has helped push back the arrival of Day Zero until early July. Hopefully, by then, the winter rains will have returned and begun recharging dams and groundwater.

More committed

So behavioural economics suggests that if people believe they are rallying around a common good, like saving water, they become more committed to doing it. But there’s a warning too, says Professor Visser: if people lose faith in each other they will turn to selfish, hoarding behaviour. There is evidence to suggest this twin pattern may apply not only with water-saving but in the case of other shared resources as well.

“The blame game that has dominated media forums is largely inaccurate and counter-productive, and it perpetuates free-riding and selfish behaviour which threatens this common resource pool”, warned Visser recently in the local press.

“The worst possible outcome right now would be if people lost faith in each other’s ability to safeguard the remaining water as part of a common pool resource, and instead rather started withdrawing water from the municipal supply for their own bulk storage.”

The message for drought-stressed cities in future, in terms of encouraging residents to willingly adopt more sustainable behaviour, is to rally them around a common cause, and build mutual trust by showing that people are cooperating towards everyone’s shared wellbeing.


Leonie Joubert is a freelance science writer and author, whose books include Scorched: South Africa’s changing climate, and Boiling Point: people in a changing climate. This article was originally published on Climate News Network.

Cover photo by Shiva Creations/Pixabay.
Climate change could cause more severe droughts in ‘98% of European cities’

Climate change could cause more severe droughts in ‘98% of European cities’

By Daisy Dunne

More than 500 European cities could face sharp increases in droughts, floods and heatwaves if climate change continues to rise unabated, a new study finds.

The UK and Ireland could experience the largest rise in urban flood risk out of any region in Europe, the research shows, while the greatest heatwave temperature increases could be felt in Austria and Germany.

The findings also show that more than 100 cities could face a rise in the risk of two or more types of extreme event by the second half of the century, with Leeds, Cardiff and Exeter featuring in the top 20% of cities at risk of both heatwave and flooding increases.

The study is “an example of what might happen if we don’t start cutting our carbon emissions in a timely fashion”, a scientist not involved in the study tells Carbon Brief.

City concerns

More than 75% of the European Union’s population live in urban areas and this figure is expected to rise to 82% by 2050.

The new study, published in Environmental Research Letters, estimates how climate change could affect the risk of flooding, drought and heatwaves in 571 European cities by the second half of the century.

For the study, the researchers used a collection of climate models to simultaneously assess the risk of floods, droughts and heatwaves for every city.

Using a high-emission pathway known as RCP8.5, the models produced “low”, “medium” and “high” impact scenarios for each location.

The researchers estimated changes in risk by comparing the likelihood of extreme events from 1951-2000 to a future period of 2051-2100.

The research shows that every European city will face an increase in extreme weather event risk as the climate warms, says lead author Dr Selma Guerreiro, a researcher in hydrology and climate change from the University of Newcastle. She tells Carbon Brief:

“The British Isles have some of the worst overall flood projections. Southern European cities will see the biggest increases in the number of heatwave days. However, the greatest heatwave temperature increases are expected in central European cities.”

Heating up

Global warming is expected to cause an increase in the number of people exposed to heatwaves in the coming centuries.

The new research defines heatwaves as three consecutive nights where temperatures are in the top 5% of the 1951-2000 average for each city.

The maps below show how the proportion of heatwave days in the summer (top) and maximum temperature (bottom) of heatwaves could change in European cities under a low, medium and high-impact scenario. On the maps, each dot shows the results for one city – with impacts ranging from small (green) to large (dark red) increases.

Change in the proportion of heatwave days in the summer (left) and maximum heatwave temperature (right) in European cities in 2051-2100 compared to 1951-2000 under a low (left), medium (middle) and high (right) scenario. Source: Guerreiro et al. (2018)

The research finds that both the number and maximum temperature of heatwaves is likely to increase for every city under all of the scenarios.

Cities in southern Europe are expected to see the greatest increase in the number of heatwave days per year, with Lefkosia and Lemesos in Cyprus facing a 69% in heatwave days by 2050 under the high scenario.

Meanwhile, the largest increases in maximum heatwave temperature are expected to occur in central European cities, with some areas experiencing a rise of 14C above previous maximum temperatures. Under the high scenario, 72% of European cities could see an increase in maximum heatwave temperature by 2050.

Projections under the high scenario also suggest that cities in the UK could face maximum heatwave temperature increases of up to 12C as the climate warms, says Guerreiro:

“The UK is less affected than most of continental Europe for the low-impact scenario, where UK cities can expect changes in maximum temperature during a heatwave between 2C and 5C. However, for the high-impact scenario the maximum temperature during a heat-wave for UK cities could increase from 7C to 12C.”

Drying out

Changing rainfall patterns as a result of climate change is expected to lead to more droughts in some parts of Europe.

For the study, the researchers used a measure known as the drought severity index (DSI), which gives a picture of drought risk over a one-year period.

The charts below show the probability of drought risk for each city in 2050, when compared to risk from 1951-2000. On the maps, light blue indicates no change, while yellow shows a small increase and dark red shows a high increase.

Probability of drought risk in European cities in 2051-2100, compared to risk from 1951-2000. Light blue indicates no change, while yellow shows a small increase and dark red shows a high increase. Source: Guerreiro et al. (2018)

The findings show that the largest increases in drought risk are expected to affect southern European cities, including Lisbon and Faro in Portugal and Seville and Barcelona in Spain, says Guerreiro:

“For the low-impact scenario, cities in the south of Iberia, such as Malaga and Almeria, are expected to experience droughts that are more than twice as bad as today. While for the high impact scenario, 98% of European cities could see worse droughts in the future.”

The research also shows that, under the high-impact scenario, 21 cities in southern Europe may experience droughts that are up to 14 times worse than the extreme droughts of 1951-2000.

Spilling over

Climate change is expected to cause an increase in flood risk in much of Europe, although the scale of this impact is likely to affected by a range of factors, such as urban planning.

To understand changes in flood risk, the researchers estimated changes to maximum river flow (or “discharge”) over a ten-year return period for each city.

This shown on the chart below, where green shows a small increase in river flows and dark red shows a large increase.

Changes in river flow (discharge) over a ten-year return period in European cities in 2051-2100, compared to 1951-2000. Green shows a small increase in flood risk and dark red shows a large increase in flood risk. Source: Guerreiro et al. (2018)

The findings show that cities in the UK and Ireland could face the largest increase in river flows out of any region in Europe, with Glasgow, Wrexham, and Aberdeen being among the most at-risk cities.

Under the low scenario, 85% of UK cities could face increased river flooding, says Guerreiro:

“The British Isles are a future hotspot for river flooding in Europe. The cities predicted to be worst hit under the high-impact scenario for the British Isles are Cork, Derry, Waterford, Wrexham, Carlisle, and Glasgow. For the low-impact scenario, Derry, Chester, Carlisle, Aberdeen, and Glasgow could be worst affected.”

‘Substantial challenge’

The findings also show that more than 100 cities in Europe could face a rise in the risk of two or more types of extreme event by the second half of the century.

In the UK, Cardiff, Exeter, Leeds and Newport fall within the top 20% of European cities at risk of both heatwave and flooding increases as the climate warms, Guerreiro says:

“We hope to highlight the substantial challenge cities face in managing climate risks and provide an encompassing view of possible future changes in climate.”

The new research advances our understanding of extreme weather risks in European cities by “considering all these hazards together,” says Dr Dann Mitchell, a researcher in climate change, extreme events and human health at the University of Bristol, who was not involved in the study.

However, it is worth bearing in mind that the research uses a high emissions trajectory for its analysis, he tells Carbon Brief:

“It would also be interesting to see how sensitive their analysis is to other greenhouse gas emissions. The emission scenario used in their study is much higher than that which would be consistent with the Paris Agreement and so their study could be thought of as an example of what might happen if we don’t start cutting our carbon emissions in a timely fashion.”


Based on: Guerreiro, S. B. et al. (2018), Future heat-waves, droughts and floods in 571 European cities, http://iopscience.iop.org/article/10.1088/1748-9326/aaaad3/meta

This article was originally published on Carbon Brief, read the original here (CC BY-NC-ND 4.0).

Cover photo by M-CARLOS/Pixabay: Dangerously low water level of the Ebro river flowing through Zaragoza, Spain, with the “Puente de Piedra” (engl. Stone Bridge) in the background.
Water scarcity threat to India and South Africa

Water scarcity threat to India and South Africa

By Alex Kirby

Water scarcity is now a real threat in two developing countries at the forefront of efforts to reduce climate change, India and South Africa. This is not the tragically familiar story of extreme weather, stunted crops and foreshortened lives. It is a different sort of threat: to urban life, to industrial development, and to attempts to end poverty.

More than 80% of India’s electricity comes from thermal power stations, burning coal, oil, gas and nuclear fuel. Now researchers from the US-based World Resources Institute, after analysing all of India’s 400+ thermal power plants, report that its power supply is increasingly in jeopardy from water shortages.

The researchers found that 90% of these thermal power plants are cooled by freshwater, and nearly 40% of them experience high water stress. The plants are increasingly vulnerable, while India remains committed to providing electricity to every household by 2019.

Between 2015 and 2050 the Indian power sector’s share of national water consumption is projected to grow from 1.4 to nine per cent, and by 2030, 70% of the country’s thermal power plants are likely to experience increased competition for water from agriculture, industry and municipalities.

Power sector choking

“Water shortages shut down power plants across India every year,” said O P Agarwal of WRI India. “When power plants rely on water sourced from scarce regions, they put electricity generation at risk and leave less water for cities, farms and families. Without urgent action, water will become a chokepoint for India’s power sector.”

Between 2013 and 2016 14 of India’s 20 largest thermal utility companies experienced one or more shutdowns because of water shortages. WRI calculates that shutdowns cost these companies over INR 91 billion ($1.4 billion) in potential revenue from the sale of power.

It says water shortages cancelled out more than 20% of the country’s growth in electricity generation in 2015 and 2016.

The report offers solutions, including notably a move towards solar and wind energy. India already has a target for 40% of its power to come from renewables by 2030, under the Paris Agreement on climate change.

“Renewable energy is a viable solution to India’s water-energy crisis,” said Deepak Krishnan, co-author of the report. “Solar PV and wind power can thrive in the same water-stressed areas where thermal plants struggle…”

A policy brief produced by WRI and the International Renewable Energy Agency details ways for India’s power sector to reduce water usage and carbon emissions by 2030.

“The challenge exceeds anything a major city has had to face anywhere in the world since the Second World War or 9/ll”

In Africa the dangers of water scarcity for one of the continent’s best-known cities, Cape Town, are imminent and, some believe, almost apocalyptic.

The city faces the prospect within three months of becoming the world’s first major city to run out of water, al-Jazeera reports.

It says the city’s water supplies are now so low that in late April it will declare “Day Zero”, the day when its reservoirs fall below a combined capacity of 13.5%.

This will mean Cape Town turning off the taps, except in the poorest neighbourhoods, and installing around 200 water collection sites across the city.

Water usage in the Western Cape province, which includes Cape Town,  is now limited to a daily ration of 87 litres per person. If Day Zero dawns, that will drop to about 25 litres. The World Health Organisation says about 20 litres should be enough “to take care of basic hygiene needs and basic food hygiene”.

Rains start later

The province has had three years of drought. Kevin Winter, a senior lecturer in environmental science at the University of Cape Town, told al-Jazeera that as a winter rainfall region, people would normally expect rainfall to start somewhere around April.

“But that’s no longer the case, it comes a whole lot later at the end of June, or in early July, if we are lucky,” he said. “We are experiencing a rapid change in our weather patterns, which is increasingly evident of a climate change…”

Bridgetti Lim Bandi, who has lived in the city all her life, said Cape Town’s rainfall pattern had changed dramatically within the last two decades. “We don’t have a traditional Cape Town winter any more,” she told al-Jazeera.

Helen Zille is premier of the Western Cape province. She wrote on 22 January in the Daily Maverick: “The question that dominates my waking hours now is: When Day Zero arrives‚ how do we make water accessible and prevent anarchy?

“And if there is any chance of still preventing it‚ what is it we can do? …the challenge exceeds anything a major city has had to face anywhere in the world since the Second World War or 9/ll.”


This article originally appeared on Climate News Network and is shared under a Creative Commons license. Read the original article here.

Cover photo by Marcelo Novais on Unsplash.
Video: Waters of Paradise – Climate change adaptation in the Maldives

Video: Waters of Paradise – Climate change adaptation in the Maldives

By Elisa Jiménez Alonso

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:

Climate change is shrinking the Colorado River

Climate change is shrinking the Colorado River

By Brad Udall, Colorado State University and Jonathan Overpeck, University of Arizona

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.

 

The Colorado River is about 1,400 miles long and flows through seven U.S. states and into Mexico. The Upper Colorado River Basin supplies approximately 90 percent of the water for the entire basin. It originates as rain and snow in the Rocky and Wasatch mountains. Source: USGS

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.

The combined contents of the nation’s two largest reservoirs, Lake Mead and Lake Powell, since their initial fillings. The large decline since 2000 is shaded brown for 2000-2014, our 15-year study period, and pink for the continuing drought in 2015-2016. The loss was significantly influenced by record-setting temperatures, unlike a similar 15-year drought in the 1950s which was driven by a lack of precipitation. Bradley Udall, Author provided

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.

The American Canal carries water from the Colorado River to farms in California’s Imperial Valley. Adam Dubrowa, FEMA/Wikipedia

On a year-in, year-out basis, these large increases would be substantial. The largest decade-long increases in precipitation in the 20th century were 8 percent. When such an increase occurred over 10 years in the Colorado Basin in the 1980s, it caused large-scale flooding that threatened the structural stability of Glen Canyon Dam, due to a spillway failure not unlike the recent collapse at California’s Oroville Dam.

For several reasons, we think these large precipitation increases will not occur. The Colorado River Basin and other areas around the globe at essentially the same latitudes, such as the Mediterranean region and areas of Chile, South Africa and Australia, are especially at risk for drying because they lie immediately poleward of the planet’s major deserts. These deserts are projected to stretch polewards as the climate warms. In the Colorado River basin, dry areas to the south are expected to encroach on some of the basin’s most productive snow and runoff areas.

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.

Several new studies indicate that with warmer temperatures, the likelihood of megadroughts skyrockets in the 21st century, to a point where the odds of one occurring are better than 80 percent. So while we might have periods with average or above-average precipitation, it also seems likely that we will have decades with less flow than normal.

Source: USEPA

Planning for lower flows

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.

The ConversationIt 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.


Brad Udall, Senior Research Scientist, Colorado Water Institute, Colorado State University and Jonathan Overpeck, Director, Institute of the Environment, Distinguished Professor of Science, and Regents’ Professor of Geosciences, Hydrology and Atmospheric Sciences, University of Arizona
This article was originally published on The Conversation. Read the original article.
Cover photo by Bettina Damgaard/Pixabay (public domain): Horseshoe Bend of Colorado River, Arizona, USA.