News Section
Stories from Climate Central's Science Journalists and Content Partners

Worsening Water Scarcity to Affect 2 Billion Globally

Repost This

By Kieran Cooke, Climate News Network

LONDON Water scarcity is a fact of life in many parts of the world, particularly in the countries of sub-Saharan Africa. A new study says the situation could get a lot worse, with climate change resulting in less rain and more evaporation in many areas.

Warming will expose 668 million people worldwide to new or aggravated water scarcity – that’s in addition to the 1.3 billion people already at present living in water-scarce regions. Credit: Nourishing the Planet

The study, led by researchers at the Potsdam Institute for Climate Impact and Research and appearing in the journal Environmental Research Letters, looks at present commitments by countries to reduce greenhouse gases (GHGs). It says that even if these commitments or pledges are met, the global mean temperature will still rise by around 3.5°C above pre-industrial levels by the end of the century.

This, according to the researchers’ calculations, will expose 668 million people worldwide to new or aggravated water scarcity – that’s in addition to the 1.3 billion people already at present living in water-scarce regions.

Using the same calculations, the study says that if the global mean temperature rises by only 2°C, at present the internationally agreed target maximum, an additional 486 million people – a figure equivalent to more than 7 percent of the world’s present population – will be threatened with severe water scarcity.

Regions which will see the most significant deterioration in water supplies are the Middle East, North Africa, southern Europe and the south-west of the U.S.

Dr. Dieter Gerten, the study’s lead author, says the main factor leading to more water shortages will be declining precipitation: increasing temperatures will also lead to greater evapotranspiration – that is the sum of evaporation and plant transpiration from the Earth’s land surface to the atmosphere.

“Even if the increase is restricted to 2°C above pre-industrial levels, many regions will have to adapt their water management and demand to a lower supply, especially since the population is expected to grow significantly in many of these regions”, says Gerten.

Even if the increase is restricted to 2°C above pre-industrial levels, many regions will have to adapt their water management and demand to a lower supply.
Credit: ביה”ס אדנים חדרה, via Climate News Network

Recognizing the impacts

It’s vital, says the study, that governments and policymakers, when setting targets on temperature rises, are fully informed of the overall consequences of their decisions.

“The unequal spatial pattern of exposure to climate change impacts sheds interesting light on the responsibility of high-emission countries and could have a bearing on both mitigation and adaption burden-sharing”, says Gerten.

The Potsdam study used material from 19 different climate change models. This was run alongside eight different global warming trajectories. In all more than 150 climate change scenarios were examined.

Researchers also examined the impact future changes in climate would have on the world’s ecosystems, seeking to identify which areas would be subject to greatest change and whether these regions were rich in biodiversity.

“At a global warming of 2°C, notable ecosystem restructuring is likely for regions such as the tundra and some semi-arid regions,” says Gerten.

“At global warming levels beyond 3°C, the area affected by significant ecosystem transformation would significantly increase and encroach into biodiversity-rich regions.

“Beyond a mean global warming of 4°C, we show with high confidence that biodiversity hotspots such as parts of the Amazon will be affected.”

Kieran Cooke is a co-editor for Climate News Network. Climate News Network is a news service led by four veteran British environmental reporters and broadcasters. It delivers news and commentary about climate change for free to media outlets worldwide.

Comments

By Frank Passarelli (Los Angeles)
on September 22nd, 2013

Fresh water for drinking, agriculture and Industrial use is an essential for mankind and is amongst one of the most important for man’s survival. The rapid increase of the world’s population, pollution and nonuniform distribution of potable water is forcing mankind to new techniques for water purification, distillation, generating the highest quality of potable water, reducing energy consumption and eliminating environmental damage. Available today is a unique process for purifying a liquid by its tendency to erupt into violent vapor when present in a negative atmosphere and unable to hold attention to the fixed elements which fall from the vapor, because of an inherent lightness of the vapor or fickleness of elements disposition and will not evaporate but become condense. This process is unlike Multi flash, Multistage and Reverse Osmosis technologies. The unique process is available to operate and maintain the operation with a primary thermal energy (steam) charge and a small makeup charge to maintain operation. The primary energy charge starts the operation and small, thermal input maintains the distillation process by circulating the thermal energy in a loop, recycling the thermal energy within the operation for the evaporation and separation of the elements and water, reducing the energy cost of drinking water. Elements falling from the vapor drop into the auger the bottom and removed..

The solution for the acute shortage of water in the world would be solved by using the new water technology P-V ES. System. Systems placed in a locations to supply water, adjacent to the facilities as it was in older times as water wells were. Water supplied from deep well of salt water are contaminated water.  This process with the lowest energy consumption for the purification and distillation of water, leaving a vapor saturated residue of rejected solids (no liquid discharge), with the smallest footprint requirement and the greatest concerns for the environment invention is an extremely low energy operation due to conservation of energy performed by recycling the energy in a thermal loop. This thermal loop utilizes the heat from the phase changes from liquid to vapor and then back from vapor to liquid distilled water by means of the heat exchanger to heat the incoming seawater ahead of the introduction into the pressure vessel. It is estimated that the energy needed for operation of P-VES is 4-5 times less energy than the best RO Systems on the market. The invention can be embodied in an apparatus of small size, or scaled in size to meet the needs of a large seawater desalination program. For example, the size of the invention apparatus to produce 1 acre foot of water per day is approximately the size of an truck trailer bed. 

The process may be operated with natural gas, electricity, thermal cogeneration and natural energy sources. The most efficient (reverse osmosis based) desalination plants consume about 5 kWh of energy per meter of fresh water produced, the P-VES would consume about 1.315 kWh of energy per meter.
This process has been designed to facilitate small and large installations at the lowest capital investment. The simplicity of the process makes the monitoring and maintenance of the system manageable by non-technical personnel. This process does not produce a brine but produces a rejected raw salt or solids for the commercial market. I have described a few of the features of the process.

WDI’s distillation process is installed at a very low capital cost allowing it to standby and the ability of adapting its production for a commodity market of drinking water. With certain limitations the production installation can be increased by adding components to the distillation apparatus process. This gives the ability to grow to the intended production capacity.

Reply to this comment

By Marni Goldberg (West Hollywood, CA 90069)
on March 17th, 2014

Insightful article, Kieran. Thank you.

In addition, water scarcity is affecting areas of the world that we would never imagine. Point in case, from http://millennialmagazine.co, California Governor Jerry Brown has declared a state of emergency citing snow levels at 20% of their normal rate. 17 California cities are in jeopardy of losing their drinking water (tap, white water) as the crisis grows, and other communities are being told to cut water usage by 25% and up to 50% by summer if conditions worsen.

In a video associated with the referenced article, http://bit.ly/1qN2Sh6, it is suggested that water will no longer be the responsibility of individual states, but rather the burden will be placed directly on the individual communities. It is also suggested that aquifers will be tapped, and that “free market” opportunities will be created on a supply and demand basis.

In one instance, 32,000 acres in the Mojave Desert (and the aquifer below) have been purchased by the Cadiz Company, and 169 billion gallons of water have already been sold to (3) Orange County communities prior to being successfully extracted from the ground.

While there are some toxicity problems linked to ground water, it is said the deeper the well the better chances of discovering fresh, clean water.

Reply to this comment

Name (required):
Email (required):
City/State/Zip:
Enter the word "climate" in the box below:

[+] View our comment guidelines.

Please note: Comment moderation is enabled. Your comment will not appear until reviewed by Climate Central staff. Thank you for your patience.