News / Science & Technology

Scientists Create 700-Year Model of Asian Monsoons

Cloud forests in the mountains of Vietnam's Bidoup Nui Ba National Park contain conifer species, including Po Mu (Fokiena hodginsii), that can live for a thousand years or more
Cloud forests in the mountains of Vietnam's Bidoup Nui Ba National Park contain conifer species, including Po Mu (Fokiena hodginsii), that can live for a thousand years or more
TEXT SIZE - +

Half the world's population is affected by Asian monsoons, yet the rainy seasons are notoriously hard to predict.  But U.S. researchers have put together a 700-year record of the Asian monsoons they hope will guide forecasters.  

Every summer, India, East Asia, eastern Africa, Indonesia and northern Australia are drenched by moist air masses called monsoons, which are pulled in by a high pressure area over the Indian Ocean and a low pressure area to the south.  

A monsoon will typically begin with no warning sometime during June, July or August, or instead of non-stop rain there may be drought conditions, which can spell disaster for subsistence farmers.

Edward Cook of the Lamont-Doherty Earth Observatory at Columbia University in New York says the complex, interrelated nature of the climate systems across Asia makes monsoons hard to predict.  He says climate records date to 1950, too recent and not detailed enough to be of much use.  

So researchers led by Cook spent more than 15 years traveling across Asia locating trees old enough to provide long-term records.  They measured the rings inside of the trunks of thousands of ancient trees at more than 300 sites.  

The investigators put together a Monsoon Asia Drought Atlas documenting monsoons over a 700-year period, beginning in the 1300s.  

Cook says the tree-ring data indicate periods of wet and dry conditions.

"If the monsoon basically fails or is very weak one year, the trees affected by the monsoon at that location might put on a very narrow ring," explains Cook.  "But if the monsoon is very strong, the trees affected by that monsoon might put on a very wide ring for that year.  So, the wide and narrow ring widths of the tree chronology that we developed in Asia provide us with a measure of monsoon variability."

Armed with such a sweeping set of data, researchers say they now can begin to refine climate computer models to try to predict the behavior of monsoons, according to Cook.

"Because the system is kind of coupled, in other words, there is nothing really truly, completely independent about those areas with respect to monsoon variability, having the information in any given year about the monsoon variability in all those regions at the same time might help us produce a more robust model for explaining how the Asian monsoon system works," he said.

Eugene Wahl is with the U.S. National Oceanic and Atmospheric Administration's paleoclimate branch, which studies weather patterns over the history of the Earth.  

Wahl says the Monsoon Asia Drought Atlas is a major accomplishment, filling in a major data gap on monsoons, which affect the lives of one half of the world's population.

"There has been widespread famine and starvation and human dying in the past in large droughts.  And on the other hand if the monsoon is particularly heavy it can cause extensive flooding.  So, to get a sense of what the regional moisture patterns have been, dryness and wetness over such a long period of time in great detail, I would call it a kind of a victory for paleoclimate science," he said.

An article describing the Monsoon Asia Drought Atlas, and accompanying commentary by Eugene Wahl, is published this week in the journal Science.   

You May Like

Algerians Vote in Presidential Election

There were few media reports of protests and clashes around the country, but so far no significant violence More

Sharks More Evolved than Previously Thought

The discovery could “profoundly affect our understanding of evolutionary history” More

Pakistan Military Asked to Protect Polio Workers

Request comes as authorities say a Taliban ban on vaccinations in 2012 and deadly attacks on anti-polio teams have prevented thousands of children from getting inoculated 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.
Google Buys Drone Companyi
|| 0:00:00
...
 
🔇
X
George Putic
April 15, 2014
In its latest purchase of high-tech companies, Google has acquired a manufacturer of solar-powered drones that can stay in the air almost indefinitely, relaying broadband Internet connection to remote areas. It is seen as yet another step in the U.S. based Web giant’s bid to bring Internet to the whole world. VOA’s George Putic reports.
Video

Video Google Buys Drone Company

In its latest purchase of high-tech companies, Google has acquired a manufacturer of solar-powered drones that can stay in the air almost indefinitely, relaying broadband Internet connection to remote areas. It is seen as yet another step in the U.S. based Web giant’s bid to bring Internet to the whole world. VOA’s George Putic reports.
Video

Video Ray Bonneville Sings the Blues and More on New CD

Singer/songwriter Ray Bonneville has released a new CD called “Easy Gone” with music that reflects his musical and personal journey from French-speaking Canada to his current home in Austin,Texas. The eclectic artist’s fan base extends from Texas to various parts of North America and Europe. VOA’s Greg Flakus reports from Austin.
Video

Video Millions Labor in Pakistan's Informal Economy

The World Bank says that in Pakistan, roughly 70 percent work in the so-called informal sector, a part of the economy that is unregulated and untaxed. VOA's Sharon Behn reports from Islamabad on how the informal sector impact's the Pakistani economy.
Video

Video Passover Celebrates Liberation from Bondage

Jewish people around the world are celebrating Passover, a commemoration of their liberation from slavery in Egypt more than 3,300 years ago. According to scripture, God helped the Jews, led by Moses, escape bondage in Egypt and cross the Red Sea into the desert. Zlatica Hoke reports that the story of the Jewish Exodus resonates with other people trying to escape slave-like conditions.
Video

Video Police Pursue Hate Crime Charges Against Kansas Shooting Suspect

Prosecutors are sifting through the evidence in the wake of Sunday’s shootings in a suburb of Kansas City, Missouri that left three people dead. A suspect in the shootings taken into custody is a white supremacist. As VOA’s Kane Farabaugh reports, he was well-known to law enforcement agencies and human rights groups alike.
Video

Video In Eastern Ukraine, Pro-unity Activists Emerge from Shadows

Amid the pro-Russian uprisings in eastern Ukraine, there is a large body of activists who support Ukrainian unity and reject Russian intervention. Their activities have remained largely underground, but they are preparing to take on their pro-Moscow opponents, as Henry Ridgwell reports from the eastern city of Donetsk.
Video

Video Basket Maker’s Skills Have World Reach

A prestigious craft show in the U.S. capital offers one-of-a-kind creations by more than 120 artists working in a variety of media. As VOA’s Julie Taboh reports from Washington, one artist lucky enough to be selected says sharing her skills with women overseas is just as significant.
Video

Video UN Report Urges Speedier Action to Avoid Climate Disaster

A new United Nations report says the world must switch from fossil fuels to cleaner energy sources to control the effects of climate change. The Intergovernmental Panel on Climate Change released the report (Sunday) following a meeting of scientists and government representatives in Berlin. The comprehensive review follows two recent IPCC reports that detail the certainty of climate change, its impacts and in this most recent report what to do about it. VOA’s Rosanne Skirble has the details.
AppleAndroid