News / Science & Technology

Tree Deaths Linked to Climate Change

Aspen, the most widespread tree in North America, is suffering from what scientists call sudden drought-induced death from climate change. (Credit: Kimberly Pham)
Aspen, the most widespread tree in North America, is suffering from what scientists call sudden drought-induced death from climate change. (Credit: Kimberly Pham)
Rosanne Skirble
Hot and dry conditions triggered by climate change are killing the world's trees, according to a new report which examines dozens of scientific articles on the subject.   

Stanford University graduate student William Anderegg has seen this forest die-off firsthand.

His doctoral thesis documents the impact of drought on trembling aspen, the most common tree in North America.

“These are complete hillsides of trembling aspens that are dying off," Anderegg says. "And when the main tree in a forest goes, you tend to see a lot of the other species, especially the grasses and the wild flowers, tend to disappear as well. But you lose a lot of those species from those forests.”  

Changing ecology

With colleagues from Stanford and North Arizona State University, Anderegg co-authored the new report which presents a picture of accelerating worldwide tree deaths that appear to be linked to changes in the global climate.

Tree Die Off Climate Change
Tree Die Off Climate Changei
|| 0:00:00
...    
🔇
X


Anderegg says these changes, triggered by rising levels of heat-trapping gases in the atmosphere, are stressing the world’s forests.

“One of the ways that we expect climate change to increasingly play out in forests is through these widespread tree mortality events where you stress the trees enough that you essentially push a whole region of them off the edge and in fact what happens afterwards, after a forest dies from drought is every bit as important and in some sense matters more to humans who rely on forests.”

  • Bug infestations like the mountain pine beetle in this lodgepole pine forest in British Columbia, Canada may be in response to a changing climate. Photo credit: Northern Forest Products Association
  • A healthy aspen stand in the San Juan Mountains in western Colorado is at risk as the climate changes. Photo credit: William Anderegg
  • Heat stress kills ponderosa pine in New Mexico. Photo credit: Craig Allen, USGS
  • The sudden Colorado aspen tree die-off near Fairplay, Colorado in 2009 has been linked to climate change. Photo credit: William Anderegg
  • Scientists seek more data to better predict climate impacts on this pinyon pine grove in New Mexico and forests elsewhere around the globe. Photo credit: Craig Allen, USGS
  • Drought triggered this forest die-off in Argentina in 2004. Photo credit: Thomas Kitzberger
  • Forests around the globe are at risk from climate change like this forest die-off in Spain because of a drought. Photo credit: Rafael Navarro-Cerrillo
  • Aspen, the most common tree in North America, is suffering from what scientists call sudden drought-induced death from climate change. Photo credit: Kimberly Pham
  • Scientists are monitoring this grove of Aspen in western Colorado to see how the trees respond to increasingly warmer temperatures. Photo credit: Kimberly Pham


Trees provide a range of ecological services. They hold soil in place, help purify water and shelter species. They are valued for timber and tourism. When trees die, the ecology and hydrology of a forest change, which in turn promotes insect infestation and fire.

This can result in long-term shifts in the area’s dominant species and may even trigger a transition to a different ecosystem, such as grass land.

Devastating consequence

Anderegg says the most devastating consequence may be that the changing forests, in turn, will start affecting the global climate.  

“Because forests do a lot to stabilize the climate and to store carbon and when they start to die off, you can actually have forest die-off accelerate climate change," he says. "You get into a vicious cycle.”

This is especially troubling for Anderegg because trees, which cover 30 percent of the earth’s surface, absorb 25 percent of the climate-changing gases emitted into the atmosphere from cars, buildings and factories.

Forest monitoring

While scientists are getting better at tracking the effects of climate change on forests, data is still sparse. Anderegg says his study urges governments and specialists from many disciplines to support wide-scale forest monitoring.  
 
“It is not just ecologists, but we also need people working with satellites. We need people in government agencies. We need people on the ground to do this as well. It’s unfortunately not something that just the scientific research community can pull off on their own.”
 
Anderegg, whose research is published in Nature Climate Change, says a better understanding of how climate change is killing off the world’s forests can help shape better forest management, business decisions and policies.

You May Like

Taliban's New Leader Says Jihad Will Continue

Top US Afghan diplomat also meets with Pakistani, Afghan officials following news of Mullah Omar's death More

Video US Landmark Pushes Endangered Species

People gathered in streets, on rooftops in Manhattan to see image highlights that covered 33 floors of Empire State Building More

World’s Widest Suspension Bridge Being Built Over Bosphorus

Once built, Yavuz Sultan Selim Bridge will span 2 kilometers with about 1.5 kilometers over water, and will be longest suspension bridge in world carrying rail system More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Astronauts Train Underwater for Deep Space Missionsi
|| 0:00:00
...    
🔇
X
George Putic
July 30, 2015 8:59 PM
Manned deep space missions are still a long way off, but space agencies are already testing procedures, equipment and human stamina for operations in extreme environment conditions. Small groups of astronauts take turns in spending days in an underwater lab, off Florida’s southern coast, simulating future missions to some remote world. VOA’s George Putic reports.
Video

Video Astronauts Train Underwater for Deep Space Missions

Manned deep space missions are still a long way off, but space agencies are already testing procedures, equipment and human stamina for operations in extreme environment conditions. Small groups of astronauts take turns in spending days in an underwater lab, off Florida’s southern coast, simulating future missions to some remote world. VOA’s George Putic reports.
Video

Video Civil Rights Leaders Struggled to Achieve Voting Rights Act

Fifty years ago, lawmakers approved, and U.S. President Lyndon Johnson signed, the Voting Rights Act of 1965. The measure outlawed racial discrimination in voting, giving millions of blacks in many parts of the southern United States federal enforcement of the right to vote. Correspondent Chris Simkins introduces us to some civil rights leaders who were on the front lines in the struggle for voting rights.
Video

Video Booming London Property a ‘Haven for Dirty Money’

Billions of dollars of so-called ‘dirty money’ from the proceeds of crime - especially from Russia - are being laundered through the London property market, according to anti-corruption activists. As Henry Ridgwell reports from the British capital, the government has pledged to crack down on the practice.
Video

Video Hometown of Boy Scouts of America Founder Reacts to Gay Leader Decision

Ottawa, Illinois, is the hometown of W.D. Boyce, who founded the Boy Scouts of America in 1910. In Ottawa, where Scouting remains an important part of the legacy of the community, the end of the organization's ban on openly gay adult leaders was seen as inevitable. VOA's Kane Farabaugh reports.
Video

Video 'Metal Muscles' Flex a New Bionic Hand

Artificial limbs, including the most complex of them – the human hand – are getting more life-like and useful due to constant advances in tiny hydraulic, pneumatic and electric motors called actuators. But now, as VOA’s George Putic reports, scientists in Germany say the future of the prosthetic hand may lie not in motors but in wires that can ‘remember’ their shape.
Video

Video Russia Accused of Abusing Interpol to Pursue Opponents

A British pro-democracy group has accused Russia of abusing the global law enforcement agency Interpol by requesting the arrest and extradition of political opponents. A new report by the group notes such requests can mean the accused are unable to travel and are often unable to open bank accounts. VOA's Henry Ridgwell reports.
Video

Video 'Positive Atmosphere' Points Toward TPP Trade Deal in Hawaii

Talks on a major new trade agreement among 12 Pacific Rim nations are said to be nearing completion in Hawaii. Some trade experts say the "positive atmosphere" at the discussions could mean a deal is within reach, but there is still hard bargaining to be done over many issues and products, including U.S. drugs and Japanese rice. VOA's Jim Randle reports.
Video

Video Genome Initiative Urgently Moves to Freeze DNA Before Species Go Extinct

Earth is in the midst of its sixth mass extinction. The last such event was caused by an asteroid 66 million years ago. It killed off the dinosaurs and practically everything else. So scientists are in a race against time to classify the estimated 11 million species alive today. So far only 2 million are described by science, and researchers are worried many will disappear before they even have a name. VOA’s Rosanne Skirble reports.
Video

Video Scientists: One-Dose Malaria Cure is Possible

Scientists have long been trying to develop an effective protection and cure for malaria - one of the deadliest diseases that affects people in tropical areas, especially children. As the World Health Organization announces plans to begin clinical trials of a promising new vaccine, scientists in South Africa report that they too are at an important threshold. George Putic reports, they are testing a compound that could be a single-dose cure for malaria.
Video

Video 'New York' Magazine Features 35 Cosby Accusers

The latest issue of 'New York' magazine features 35 women who say they were drugged and raped by film and television celebrity Bill Cosby. The women are aged from 44 to 80 and come from different walks of life and races. The magazine interviewed each of them separately, but Zlatica Hoke reports their stories are similar.
Video

Video US Calls Fight Against Human Trafficking a Must Win

The United States is promising not to give up its fight against what Secretary of State John Kerry calls the “scourge” of modern slavery. Officials released the country’s annual human trafficking report Monday – a report that’s being met with some criticism. VOA’s National Security correspondent Jeff Seldin has more from the State Department.
Video

Video Washington DC Underground Streetcar Station to Become Arts Venue

Abandoned more than 50 years ago, the underground streetcar station in Washington D.C.’s historic DuPont Circle district is about to be reborn. The plan calls for turning the spacious underground platforms - once meant to be a transportation hub, - into a unique space for art exhibitions, presentations, concerts and even a film set. Roman Mamonov has more from beneath the streets of the U.S. capital. Joy Wagner narrates his report.
Video

Video Europe’s Twin Crises Collide in Greece as Migrant Numbers Soar

Greece has replaced Italy as the main gateway for migrants into Europe, with more than 100,000 arrivals in the first six months of 2015. Many want to move further into Europe and escape Greece’s economic crisis, but they face widespread dangers on the journey overland through the Balkans. VOA's Henry Ridgwell reports.
Video

Video Stink Intensifies as Lebanon’s Trash Crisis Continues

After the closure of a major rubbish dump a week ago, the streets of Beirut are filling up with trash. Having failed to draw up a plan B, politicians are struggling to deal with the problem. John Owens has more for VOA from Beirut.
Video

Video Paris Rolls Out Blueprint to Fight Climate Change

A U.N. climate conference in December aims to produce an ambitious agreement to fight heat-trapping greenhouse gases. But many local governments are not waiting, and have drafted their own climate action plans. That’s the case with Paris — which is getting special attention, since it’s hosting the climate summit. Lisa Bryant takes a look for VOA at the transformation of the French capital into an eco-city.

VOA Blogs