News / Science & Technology

Global Warming Might Threaten Water Supply

Frank Gehrke, right, Chief of California Cooperative Snow Surveys Program measures the snowpack in California’s Sierra Nevada Mountains. (California Dept. of Water Resources)
Frank Gehrke, right, Chief of California Cooperative Snow Surveys Program measures the snowpack in California’s Sierra Nevada Mountains. (California Dept. of Water Resources)
Rosanne Skirble
Global warming over the next century could significantly reduce the amount of winter snowpack in mountainous areas in the northern hemisphere, according to a new study published in Nature Climate Change.

Seasonal snowpack melt is an essential source of fresh water, and its loss could threaten drinking water supplies, agricultural irrigation and wildlife ecosystems.

Stanford University climate expert Noah Diffenbaugh led the study, which compares snowpack conditions across the northern hemisphere in the late 20th century with climate model projections for the next one hundred years.

Deceasing snowpack

Those projections are based on a range of scenarios which foresee a rise in average global temperatures of between two and four degrees Celsius.

Snowpack Climate Change
Snowpack Climate Changei
|| 0:00:00
...    
🔇
X

The study concludes that average snow accumulation will decrease in most regions of the Western United States, Europe, Central Asia and the Himalayas, compared to historical patterns.  

It projects that low and extremely low snow falls would exceed the lows of the later 20th century between 10 and 30 percent of the time with two degrees of warming.
California is the world’s sixth largest agricultural exporter and is dependent on snowpack for those crops. (California Dept. of Water Resources)California is the world’s sixth largest agricultural exporter and is dependent on snowpack for those crops. (California Dept. of Water Resources)
x
California is the world’s sixth largest agricultural exporter and is dependent on snowpack for those crops. (California Dept. of Water Resources)
California is the world’s sixth largest agricultural exporter and is dependent on snowpack for those crops. (California Dept. of Water Resources)

And, Diffenbaugh says, "If the planet warms by 4 degrees Celsius, the United could experience snowpack accumulations below the levels of the late 20th century up to 80 percent of the years.”

The story is the same in other parts of the northern hemisphere, where snowpack is a natural, and critical, water reservoir.  

Water worries

The study finds that an early spring melt would bring more water into the watershed sooner than usual, potentially flooding rivers, lakes and artificially dammed-river reservoirs.

And with less water available later in the season, chances for more wildfires, pests, and species extinctions increase.  

Diffenbaugh says this timing would also exacerbate drought conditions when the demand for water is greatest.

“We can infer that should these physical climate changes occur in the future, that there would be impacts on water supply for agriculture and for human consumption and for natural ecosystems if the water storage and management systems are not adapted to those changes.”

According to climate models, extreme rain events are expected to increase as the planet warms.  

However, Diffenbaugh says, that won’t change how the snowpack responds to climate change. 

“Even where there are increases in extreme precipitation in the models, there are still robust decreases in the amount of snowpack on the ground at the end of the winter and in robust changes in the timing of runoff.”

California experiencing climate extremes

Frank Gehrke takes these findings very seriously. He heads the California Cooperative Snow Surveys program, which forecasts water flow from the mountains into man-made reservoirs that provide water for crops and people.

California is just one part of a broader picture discussed in the report. Since the state gets little rain in the spring and summer, Gehrke says timing of snow pack melt is critical.  

He says he is seeing greater climate variation than ever before. “We’re having more extremes in terms of dry and wet years. We see that not only in our record, but also in discussions with a lot of other people who are studying climate.”  
California will fine tune its snowpack measurements using new instruments on aircraft that can give water managers accurate data on snow accumulation and rate of melt. (NASA)California will fine tune its snowpack measurements using new instruments on aircraft that can give water managers accurate data on snow accumulation and rate of melt. (NASA)
x
California will fine tune its snowpack measurements using new instruments on aircraft that can give water managers accurate data on snow accumulation and rate of melt. (NASA)
California will fine tune its snowpack measurements using new instruments on aircraft that can give water managers accurate data on snow accumulation and rate of melt. (NASA)

Gehrke says California water managers need better measurement tools and higher resolution aerial images of the state’s snowpack than were available in the Stanford study. For that, the state has turned to the U.S. space agency’s Airborne Snow Observatory.  

Flying at altitudes of about 7,000 meters, the photo-reconnaissance aircraft capture detailed images of mountain snowpack over a wide area, allowing scientists to more accurately compute the entire volume of water in a given watershed.   

The NASA flights will also measure how much sun is reflected from the snowpack, which can indicate how fast it is likely to melt.

You May Like

Lesotho Faces New Round of Violence, Political Crisis

Brutal killing of military officer has sent former leaders back into S. Africa where they're watching anxiously as regional officials head in to try to restore peace More

Video US Diplomat Expects Adoption of Bosnian Massacre Anniversary Resolution

Samantha Power says there's broad consensus about killings in Bosnia's war, but Russia calls resolution 'divisive,' backs UN countermeasure More

UN Report Exposes Widespread Boko Haram Atrocities

Damning report graphically details pattern of vicious, widespread atrocities committed by Islamist militants More

This forum has been closed.
Comment Sorting
Comments
     
by: riano baggy from: ina
November 12, 2012 12:04 AM
next decade we didn't see snow in high mountains,melting ice can high sea level,very ports must redesign again to more budget,ecosystem disturbed. and many side effect can appears..

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Olympics Construction Scars Sacred Korean Mountaini
X
July 02, 2015 4:10 AM
Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Olympics Construction Scars Sacred Korean Mountain

Environmentalists in South Korea are protesting a Winter Olympics construction project to build a ski slope through a 500-year-old protected forest. Brian Padden reports that although there is strong national support for hosting the 2018 Pyeongchang Winter Olympics, there are growing public concerns over the costs and possible ecological damage at the revered mountain.
Video

Video Xenophobia Victims in South Africa Flee Violence, Then Return

Many Malawians fled South Africa early this year after xenophobic attacks on African immigrants. But many quickly found life was no better at home and have returned to South Africa – often illegally and without jobs, and facing the tough task of having to start over. Lameck Masina and Anita Powell file from Johannesburg.
Video

Video Family of American Marine Calls for Release From Iranian Prison

As the crowd of journalists covering the Iran talks swells, so too do the opportunities for media coverage.  Hoping to catch the attention of high-level diplomats, the family of American-Iranian marine Amir Hekmati is in Vienna, pleading for his release from an Iranian prison after nearly 4 years.  VOA’s Heather Murdock reports from Vienna.
Video

Video UK Holds Terror Drill as MPs Mull Tunisia Response

After pledging a tough response to last Friday’s terror attack in Tunisia, which came just days before the 10th anniversary of the bomb attacks on London’s transport network, British security services are shifting their focus to overseas counter-terror operations. VOA's Henry Ridgwell has more.
Video

Video Obama on Cuba: This is What Change Looks Like

President Barack Obama says the United States will soon reopen its embassy in Cuba for the first time since 1961, ending a half-century of isolation. VOA White House correspondent Luis Ramirez reports.
Video

Video Hate Groups Spread Influence Via Internet

Hate groups of various kinds are using the Internet for propaganda and recruitment, and a Jewish human rights organization that monitors these groups, the Simon Wiesenthal Center, says their influence is growing. The messages are different, but the calls to hatred or violence are similar. VOA's Mike O’Sullivan reports.
Video

Video US Silica Sand Mining Surge Worries Illinois Residents, Businesses

Increased domestic U.S. oil and gas production, thanks to advances known as “fracking,” has created a boom for other industries supporting that extraction. Demand for silica sand, used in fracking, could triple over the next five years. In the Midwest state of Illinois, people living near the mines are worried about how increased silica sand mining will affect their businesses and their health. VOA’s Kane Farabaugh has more in this first of a series of reports.
Video

Video Blind Somali Journalist Defies Odds in Mogadishu

Despite improving security in the last few years, Somalia remains one of the most dangerous countries to be a journalist – even more so for someone who cannot see. Abdulaziz Billow has the story of journalist Abdifatah Hassan Kalgacal, who has been reporting from the Somali capital for the last decade despite being blind.
Video

Video Texas Defies Same-Sex Marriage Ruling

Texas state officials have criticized the US Supreme Court decision giving same-sex couples the right to marry nationwide. The attorney general of Texas says last week's decision did not overrule constitutional "rights of religious liberty," and therefore officials performing wedding services can refuse to perform them for same-sex couples if it is against their religious beliefs. Zlatica Hoke reports on the controversy.
Video

Video Rabbi Hits Road to Heal Jewish-Muslim Relations in France

France is on high alert after last week's terrorist attack near the city Lyon, just six months after deadly Paris shootings. The attack have added new tensions to relations between French Jews and Muslims. France’s Jewish and Muslim communities also share a common heritage, though, and as far as one French rabbi is concerned, they are destined to be friends. From the Paris suburb of La Courneuve, Lisa Bryant reports about Rabbi Michel Serfaty and his friendship bus.
Video

Video Saudi Leaks Expose ‘Checkbook Diplomacy’ In Battle With Iran

Saudi Arabia’s willingness to wield its oil money on the global diplomatic stage appears to have been laid bare, after the website WikiLeaks published tens of thousands of leaked cables from Riyadh’s Ministry of Foreign Affairs. VOA's Henry Ridgwell reports.
Video

Video In Kenya, Police Said to Shoot First, Ask Questions Later

An organization that documents torture and extrajudicial killings says Kenyan police were responsible for 1,252 shooting deaths in five cities, including Nairobi, between 2009 and 2014, representing 67 percent of all gun deaths in the areas reviewed. Gabe Joselow has more from Nairobi.

VOA Blogs