Land surface processes over Indian summer monsoon region: A review

Abstract

The earth’s surface continuously interacts with the overlying atmosphere through the exchange of mass, moisture and momentum, thereby altering the energy and water cycles. Through this, the earth's surface affects regional energetics, which via scale-interaction influences weather and climate systems. The land surface feedbacks are dominant over the Indian Monsoon Region (IMR) and exert impact on the atmospheric responses such as convection and precipitation through boundary layer coupling. As a result, the land surface processes associated with Indian Summer Monsoon (ISM) need to be understood and realistically represented in Numerical Weather Prediction (NWP) and regional/global climate models. The ISM is a multiscale system influenced by the boundary forcing from both the continent and tropical oceans, as well as from various boundary layer feedback mechanism. The ISM and associated rainfall is a complex system owing to non-linear interaction between large-scale fields and small-scale convective activities. The ISM is notably influenced by the local and regional scale land surface interactions. This paper reviews the recent developments related to land surface processes and their application to ISM process studies. The evolution of land surface models, state-of-art Land Data Assimilation Systems (LDAS) and their applications in NWP models are discussed.