Tuesday, March 4, 2014

New paper finds "remarkable" growth of glaciers on Tibet plateau over past decade "challenging to explain"

A paper published today in the Journal of Geophysical Research Solid Earth finds the high Asian mountain inner Tibet Plateau glaciers are gaining remarkable quantities of ice mass. According to the authors, there is a "remarkable positive signal (+30 Gigatons/yr) in the inner Tibet Plateau, which is challenging to explain" and almost completely offsets loss of 35Gt/yr elsewhere in the region.

The authors explain a 5-year cycle found in other Asian high mountain glacier mass as due to the natural "influence of Arctic Oscillation and El Niño-Southern Oscillation."

Evaluation of Glacier Changes in High Mountain Asia Based on 10-year GRACE-RL05 Models
Shuang Yi*, Wenke Sun

In this paper, 10 years of time-variable gravity data from the Gravity Recovery and Climate Experiment (GRACE) Release 05 have been used to evaluate the glacier melting rate in High Mountain Asia (HMA) using a new computing scheme, i.e., the Space Domain Inverse (SADI) method. We find that in HMA area there are three different kinds of signal sources that should be treated together. The two generally accepted sources, glacier melting and India underground water depletion, are estimated to change at the rate of -35.0 ± 5.8 Gt/yr (0.09 mm/yr sea level rising) and -30.6 ± 5.0 Gt/yr, respectively. The third source is the remarkable positive signal (+30 Gt/yr) in the inner Tibet Plateau, which is challenging to explain. Further, we have found that there is a five-year undulation in Pamir and Karakoram, which can explain the controversies of the previous studies on the glacier melting rate here. This five-year signal can be explained by the influence of Arctic Oscillation and El Niño-Southern Oscillation.

1 comment:

  1. Someone sent me a link to this, not sure why. But ...a quick search on the phrase, “Tibet Precipitation Increase” reveals that Tibet has been getting a good bit more precipitation of late. Tree ring studies indicate that Tibet tends to get more rain during warmer periods. This is probably because a warmed atmosphere holds more water and thus, there is more precipitation. Of course, even though it’s a bit warmer in Tibet, it is sill cold enough there that much of the precipitation falls as snow and accumulates as additions to the glaciers. Look it up yourself and send out that information as well just to be honest.