Anthropogenic Influence on Surface Air Temperature and Precipitation Variations Over India

Present-day climatic conditions have resulted in a huge variation in the temperature and precipitation globally as well as regionally. Additionally, rapid industrialization transformed humans from an agrarian society to an industrial society and has led to increased levels of harmful emissions resulting in global warming. In this regard, monitoring and analysis of atmospheric temperature and precipitation on regional scales have acquired particular importance in the last few decades over the Indian subcontinent. Greenhouse gases (GHGs) and aerosols might be the major contributing factors to the changes in the climate. Aerosols have a major influence on the weakening of the summer monsoon rainfall over India. An attribution study has also shown anthropogenic factors as a major cause of temperature extremes. In this study, both observational and CMIP6 model-based analysis is done to identify the contributing factors for the evident variabilities in temperature and precipitation. A preliminary analysis from observation data reveals that the temperature over the Indian region is showing a significant increasing trend in recent decades. Model analysis has shown that the changes in precipitation and temperature due to GHG forcings are escalating in the recent past. The domination of aerosols or GHGs can also provide vital information on the increased frequency, intensity, and duration of temperature and precipitation extremes.