Variability of Precipitation regime in Ladakh region of India from 1901-2000

Abstract

Ladakh region being a high elevation cold desert of India is marked by extreme aridity with acute moisture deficit throughout the year. Annual precipitation is extremely low due to rain shadow effect caused by Karakoram ranges on one side, mighty Greater Himalayas and Zanskar ranges on the other side. The study of precipitation variability is extremely important for a region like Ladakh, in which the lifestyle of inhabitants, agriculture, live stock rearing and water resources are dependent on the nature and magnitude of precipitation. Despite experiencing low precipitation, extremely low temperature enables Ladakh to contain some of the largest alpine glaciers in the world. These glaciers feed a number of river systems including Indus being the largest and the most important. The precipitation regime however has shown a changing trend over the period of time. In this backdrop, the present study attempts to analyze, core summer and core winter trends to ascertain the temporal variability in the precipitation regime from 1901-2000. Mann-Kendall test (non-parametric test) has been used to analyze the significance levels. Results for summer season show non-significant results with a test statistic of -1.102 with decrease of the order of 0.127 mm per year while for winter season Mann-Kendall test shows a rise of 0.04 mm per year showing significant trend with test statistic of 1.92 at 0.10 significance levels. The results are indicative of decreasing precipitation during summers and increasing precipitation off late during winters which will have a profound impact on the glacial environment of Ladakh region.