Current status of aerosol-cloud interactions and their impact over the Northern Indian Ocean: A comprehensive review

The interactions between aerosol and cloud play a vital role in global climate change and associated with one of the largest uncertainties. In last few decades, due to unique geographical location, Northern Indian Ocean (NIO) gains significant scrutiny among the scientific communities. The in-depth understanding of aerosols and their interaction with cloud over this region is very important on a regional as well as global perspective. This review attempts to provides (a) an overview of the aerosol loading, cloud occurrence patterns and their trends in last two decades over the NIO (b) current understanding of aerosol-cloud interaction (ACI) over the NIO and (c) impacts of ACI on the oceanic ecosystem and Indian Summer Monsoon (ISM). We found a strong spatio-temporal variability and positive trend in aerosol loading and cloud parameters which is largely modulated by the wind circulation pattern and Inter Tropical Convergence Zone (ITCZ) movement. Long range transportation is the key process in aerosol loading over the study region and significant contribution of continental aerosol over the central AS (31%) and central BoB (28%) is found. The current study concludes that the interaction between aerosol and cloud parameters may not be casual and depends on several other factors and their impact on ocean ecosystem and ISM is still remains complex problem. Thus, further studies of ACI under different atmospheric conditions and their impacts on oceanic ecosystem as well as ISM are urgently needed which will be helpful in reduction of uncertainties in regional climate change prediction.