Featured Research

from universities, journals, and other organizations

Meltwater from Tibetan glaciers floods pastures

Date:
January 16, 2014
Source:
University of Zurich
Summary:
Glaciers are important indicators of climate change. Global warming causes mountain glaciers to melt, which, apart from the shrinking of the Greenlandic and Antarctic ice sheets, is regarded as one of the main causes of the present global sea-level rise. Tibet’s glaciers are also losing mass clearly, as scientists reveal using satellite-based laser measurements. Over the last decade, the research team has detected a “clear loss in mass of around 16 gigatons a year in around 80 percent of the Tibetan glaciers,” says a glaciologist.

Shrinking glacier in south-west Tibet.
Credit: Niklas Neckel; Universität Tübingen

Glaciers are important indicators of climate change. Global warming causes mountain glaciers to melt, which, apart from the shrinking of the Greenlandic and Antarctic ice sheets, is regarded as one of the main causes of the present global sea-level rise. Tibet's glaciers are also losing mass clearly, as scientists from the universities of Zurich, Tubingen and Dresden reveal using satellite-based laser measurements. Over the last decade, the research team has detected a "clear loss in mass of around 16 gigatons a year in around 80 percent of the Tibetan glaciers," says Tobias Bolch, a glaciologist from the University of Zurich involved in the study -- that's more than four times the volume of water in Lake Zurich and around six percent of the total loss in mass of all the glaciers on Earth.

Some glaciers in Tibet are growing

However, the measurements also bore some positive news: Some glaciers in the central and north-western part of the Tibetan Plateau have actually grown in mass. While the glaciers in the monsoon-influenced southern and eastern part of the plateau have melted significantly, the scientists recorded a neutral or even slightly positive result in the continental central and north-western area of the country. Nonetheless, as Bolch notes, "On average, the entire region is clearly characterized by a loss in mass."

At a first glance, the evidence that not all of the meltwater flows into the ocean via the large Asian currents and causes the sea level to rise seems positive. "However, flooding is still a problem," says Bolch. After all, a large proportion of the melt -- around two gigatons a year, as scientists have quantified for the first time -- flows into lakes without an outlet on the plateau, causing them to burst their banks. "In many regions, this means that valuable pasture areas become submerged," explains the glaciologist.

Precise results thanks to a combined measuring technique

Stretching over an area of around 40,000 square kilometers, the Tibetan Plateau's glaciers account for over a third of High Asia's ice cover and are about twenty times the size of the ice surface of the Alps. For their study, the international team of researchers evaluated satellite-based laser measurements of the glacier surfaces on the Tibetan Plateau between 2003 and 2009. "Thanks to these measurements, we were able to gauge the temporal changes of the glacier heights and -- combined with a detailed glacier inventory -- changes in mass of the glaciers in Tibet, which are extremely difficult to access," say Tubingen scientists Niklas Neckel and Jan Kropacek, explaining the measuring technique.

The results now published in Environmental Research Letters seem to contradict the data from a satellite mission based on other measuring methods, which indicates a slight increase in mass in the glacier ice for an almost identical period of time. For Bolch, the different measurement values depend on the amounts of meltwater that remain on the plateau and do not flow away into the sea -- and which his team has now managed to measure accurately for the first time. He attributes the data from the other studies that points to glacial growth more to other influences on the calculations -- such as an increase in rainfall.


Story Source:

The above story is based on materials provided by University of Zurich. Note: Materials may be edited for content and length.


Journal Reference:

  1. Niklas Neckel, Jan Kropacek, Tobias Bolch and Volker Hochschild. Glacier mass changes on the Tibetan Plateau 2003 – 2009 derived from ICESat laser altimetry measurements. Environmental Research Letters, January 2014

Cite This Page:

University of Zurich. "Meltwater from Tibetan glaciers floods pastures." ScienceDaily. ScienceDaily, 16 January 2014. <www.sciencedaily.com/releases/2014/01/140116085057.htm>.
University of Zurich. (2014, January 16). Meltwater from Tibetan glaciers floods pastures. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2014/01/140116085057.htm
University of Zurich. "Meltwater from Tibetan glaciers floods pastures." ScienceDaily. www.sciencedaily.com/releases/2014/01/140116085057.htm (accessed September 18, 2014).

Share This



More Earth & Climate News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) — Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Man Floats for 31 Hours in Gulf Waters

Man Floats for 31 Hours in Gulf Waters

AP (Sep. 16, 2014) — A Texas man is lucky to be alive after he and three others floated for more than a day in the Gulf of Mexico when their boat sank during a fishing trip. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Researchers Explore Shipwrecks Off Calif. Coast

Researchers Explore Shipwrecks Off Calif. Coast

AP (Sep. 16, 2014) — Federal researchers are exploring more than a dozen underwater sites where they believe ships sank in the treacherous waters west of San Francisco in the decades following the Gold Rush. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Isolated N. Korea Asks For International Help With Volcano

Isolated N. Korea Asks For International Help With Volcano

Newsy (Sep. 16, 2014) — Mount Paektu volcano in North Korea is showing signs of life and there's not much known about it. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins