Scientists warn of climate change's impact on global river flow

Oct 12, 2007

A global analysis of the potential effect of climate change on river basins indicates that many rivers impacted by dams or extensive development will require significant management interventions to protect ecosystems and people, according to an article published today in the online version of Frontiers in Ecology and the Environment.

“As a result of damming and development, major rivers worldwide have experienced dramatic changes in flow, reducing their natural ability to adjust to and absorb disturbances,” said lead author Dr. Margaret Palmer, Director of the University of Maryland Center for Environmental Science Chesapeake Biological Laboratory. “Given expected changes in global climate and water needs, this could lead to serious problems for both ecosystems and people.”

In their analysis, the authors project river discharge under different climate and water withdrawal scenarios and combine this with data on the impact of dams on large river basins. The results are presented in global maps illustrating potential changes in discharge and water stress for dam-impacted and free-flowing basins.

The projections indicate that every populated basin in the world will experience changes in river discharge – some are expected to have large increases in flood flows while other basins will experience water stress such that there is not enough water to meet human needs. For example, by the 2050’s, mean annual river discharge is expected to increase by about 20 percent in the Potomac and Hudson River basins but to decrease by about 20 percent in Oregon’s Klamath River and California’s Sacramento River.

The magnitude of the changes is used to identify basins likely and almost certain to require proactive or reactive management intervention. The study also finds that nearly one billion people live in areas likely to require action and approximately 365 million people live in basins almost certain to require action.

Specific, proactive restoration, rehabilitation, and management actions are recommended to enhance the resilience of riverine ecosystems and minimize impacts. These efforts will minimize risks to ecosystems and people and may be less costly than reactive efforts taken only once problems have arisen. Proactive actions include stormwater and sediment management, channel reconfiguration, dam removal, land acquisition and riparian management.

“This report calls attention to significant risks facing many of the world’s major rivers and those people who live near or depend on them for water or food,” said Palmer. “Many of these risks could be reduced dramatically if proactive management measures are implemented now. It’s now up to the world’s political leaders to decide whether or not to step forward and put in place programs designed to minimize the impacts we may see on our ecosystems and people.”

Source: University of Maryland

Explore further: Video gives astronaut's-eye view inside NASA's Orion spacecraft

add to favorites email to friend print save as pdf

Related Stories

Deforestation threatens species richness in streams

Dec 18, 2014

With a population of 1.3 billion, China is under immense pressure to convert suitable areas into arable land in order to ensure a continued food supply for its people. Accordingly, China is among the top ...

Confucian thought and China's environmental dilemmas

Dec 18, 2014

Conventional wisdom holds that China - the world's most populous country - is an inveterate polluter, that it puts economic goals above conservation in every instance. So China's recent moves toward an apparent ...

Improving forecasts for rain-on-snow flooding

Dec 18, 2014

Many of the worst West Coast winter floods pack a double punch. Heavy rains and melting snow wash down the mountains together to breach riverbanks, wash out roads and flood buildings.

Recommended for you

SDO captures images of two mid-level flares

Dec 19, 2014

The sun emitted a mid-level flare on Dec. 18, 2014, at 4:58 p.m. EST. NASA's Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts ...

Why is Venus so horrible?

Dec 19, 2014

Venus sucks. Seriously, it's the worst. The global temperature is as hot as an oven, the atmospheric pressure is 90 times Earth, and it rains sulfuric acid. Every part of the surface of Venus would kill you ...

Image: Christmas wrapping the Sentinel-3A antenna

Dec 19, 2014

The moment a team of technicians, gowned like hospital surgeons, wraps the Sentinel-3A radar altimeter in multilayer insulation to protect it from the temperature extremes found in Earth orbit.

Video: Flying over Becquerel

Dec 19, 2014

This latest release from the camera on ESA's Mars Express is a simulated flight over the Becquerel crater, showing large-scale deposits of sedimentary material.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.