The Mass Balances Modeling And The Relationship With Meteorological Parameters On Glaciers In Tianshan, Xinjiang, China

Glacier mass balance refers to the amount of income and expenditure of the glacier in a period of time. The mass balance is the water and heat and other climatic factors combined result of the glacier, the dynamic changes directly affect the size of glacier and runoff changes. The mass balance changes in glacier is a direct response to the climate change and also is the key factors of linking the climate change. With the observation and modeling of the mass balance in the glacial area, research in mass balance related to climatic factors and its simulation, which reveals the glacier ablation mechanism and the water cycle regularity, provide a scientific basis for its investigation and assessment to the regional water resources.Tianshan Mountain glacier monitoring station, Chinese Academy of researchers carried out a comprehensive scientific exploration activities at the Shenqi Peak Glacier, Tuomuer Area in2008. Shenqi Peak Glacier can also be called Qingbingtan Glacier No.72. During July30to August30in2008, an observation of glacier ablation was made on the area between3760m to3964m a.s.l on the terminus of Qingbingtan Glacier No.72. Based on the observation, the ablation features are discussed in this paper. There existed a short warmer period on the glacier, with the maximum ablation mainly in August1-4and the mean daily net ablation of about197.6mm water equivalent w.e. and400mm w.e.. at the altitude of3760m a.s.l.. Meanwhile, the ablation generally decreases with altitude. The ablation gradient is about0.07-1.63mm-10m-1on the bare ice and0.37-9.46mm-10m-1m on the debris-covered ice. The glacier ablation is large as compared with the observation on other glaciers, according to the background of the southern Tuomuer area warming.The main conclusions by collating meteorological datas are as follows:The average daily temperature fluctuations always appear before and after precipitation, for the reason is that relatively large changes in temperature values before and after precipitation. The high temperature and low humidity day and the cold and humidity day interval appears. The low temperature and humidity day continued for some time, followed by the high temperature and low humidity day, then followed by the low temperature and humidity day, which shows relationship between the temperature and relative humidity is the inversely related. There is a peak in daily temperature change, the highest values found in around18:00pm, in line with the near surface temperature diurnal variation. Temperature changes with solar radiation balance every day in which appears a maximum value, generally appears in the afternoon, the lowest values appears before and after sunrise. The daily average relative humidity in glaciers is65.01%. Diurnal variation of the relative humidity is bimodal, with daily temperature changes is the related inversely, the maximum and minimum relative humidity values appears around5:00am and12:00pm. There is a valley shape below the elevation of3950m in glacier area, local circulation-valley wind is more development.We have received the glacial weather data, including temperature, precipitation and other first-hand weather information during July30,2008to August30,2008at3950m a.s.l. Combining parameters of different weather conditions and melting of glacier, we explore the relationship between the meteorological parameters and the melting glaciers at the Qingbingtan Glacier No.72in the ice extremely high altitudes (3950m a.s.l.). The result show that the glacier is in the melting state, the glacier average daily temperature that is above0℃reached96%in the number of days, the regression coefficient between temperature and mass balance is0.631, the grey entropy correlation coefficient between precipitation and mass balance is0.497. The relationship between the material balance and temperature is close in the ablation period. The glaciers have the cooling effect, causing the temperature on the glaciers is not a direct and immediate feedback. The glacier itself absorb heat from the sun, part of the heat to warm the glacier itself, another part of the heat to melt the ice and snow on the surface of the glacier. The thickness of debris on the surface of the glaciers also affect the ablation of the glaciers in some extent. The precipitation influences in different seasons is different. In this study period, precipitation is positively associated with the mass balance. Changes in temperature and precipitation combine effect of the process of the mass balance changes, but the temperature plays a dominant role.Degree-day model based on the DEM is on the top of the traditional study in the glacier by using of geographic information technologies. It is the ideal way to research mass balance evolution and represents the latest application of the direction of the degree-day model. In this study, the required parameters that are distributed by the DEM data are fixed. We calculate the mass balance in the period of1988/08-2003/08, and the correlation coefficient between the simulated values and observed values is0.98.