Meteorological Conditions for Frequent Debris Flows from Guxiang Glacier, Mount Nyenchen Tanglha, China

Jiankang Liu,Qinghui Li,Zunlan Cheng

doi:10.1659/mrd-journal-d-12-00053.1

Abstract

Destructive debris flows occur frequently on glacierized Mount Nyenchen Tanglha, Bomi, Tibet. Since 1953, hundreds of such flows have occurred in the Guxiang valley during periods of atypically hot or rainy weather in summer or early autumn. From 1964 to 1965, 95 debris flows were documented at a temporary debris flow observation station; 25 of these debris flows with a peak discharge Q(max) above 50 m(3)/s were considered in the present study. Supported by meteorological data from the nearby Bomi station, statistical analysis showed that outburst debris flows from the Guxiang glacier are highly correlated with atypical weather. Finally, the conditional probability of a debris flow from the Guxiang glacier as a function of daily rainfall R and maximum temperature T-max for rainy days (R >= 5 mm) and dry days (R < 5 mm) is suggested as a plausible link between weather and outbursts of debris flow.

Highlights

Destructive debris flows frequently move along the stream valleys of the glacierized Mount Nyenchen Tanglha, which is widely covered by the largest maritime glacier in Tibet
In order to discuss these relationships between debris flow and meteorological conditions, with less mutual interference, we examined the statistical distribution of rainfall excluding dry days and that of maximum temperature excluding rainy days
Favorable geomorphic factors and characteristics of maritime glaciers account for the initial conditions for most or all of the debris flows

Summary

Introduction

Destructive debris flows frequently move along the stream valleys of the glacierized Mount Nyenchen Tanglha, which is widely covered by the largest maritime glacier in Tibet. The conditional probability of a debris flow from the Guxiang glacier as a function of daily rainfall R and maximum temperature Tmax for rainy days (R $ 5mm) and dry days (R , 5 mm) is suggested as a plausible link between weather and outburst debris flows.

Results

Conclusion