Lichen biomonitoring, a valuable proxy for interpreting climate change phenomenon in Himalayas: exploring causes for glacier lake outburst flood in Kedarnath region

In recent years the frequency of cloud burst has increased tremendously and global temperature rise is considered to be among the major causes for the devastating flood. The mean temperature of the earth has increased 0.75° C since nineteenth century, which resulted in faster evaporation rate from high altitude glacial lakes, an important causes of frequent cloud burst in the high altitude region. The global precipitation data covering between the years 1979–2007 shows the changes of precipitation extremes and has been found that precipitation intensity increases by about 95% for each degree Kelvin (K) increase in global mean temperature (Liu et al. 2009). As a result during last century due to global warming, faster destruction of mountain or valley glacier has been observed. This phenomenon is already witnessed in Himalaya where glacier and glacial lakes are changing alarmingly. Glacier retreating rate in Himalaya is 10 to 60 m per year. Large number of small glaciers (<0.2 sq km) have already disappeared (Das 2015). A valuable information on local warming may gathered by tracking changes in the timber-line species as they represent the threshold of their climatic limits. Any change in climate, which disturbs the vegetation–climate equilibrium reflects significant changes in the demographic pattern of species. Studies on the impact of ongoing warming under the background influence of greenhouse gases also show that during the past few decade plant species have shifted to higher elevations and the shifting rate varies with species and largely depends on their sensitivity to climate. The change in high rate of upward shift of Himalayan pine has been observed by Dubey et al. (2003). In the Indian Himalayas, Western Himalaya is more prone to warming due to heavy industrialisation and urbanisation. The climate records of Shimla (Western Himalaya) show warming of 0.54°C during the 20th century (Dubey et al. 2003). Mukherjee (2014) studied the influence of the solar flux clubbed with the anthropogenic activities. Prior to Publication Info