Aerosol–cloud–precipitation interactions: A challenging problem in regional environment and climate research--颗粒学报PARTICUOLOGY

Devara, P. C. S., & Manoj, M. G. (2013). Aerosol–cloud–precipitation interactions: A challenging problem in regional environment and climate research. Particuology, 11(1), 25–33. https://doi.org/10.1016/j.partic.2012.07.006

Aerosol–cloud–precipitation interactions: A challenging problem in regional environment and climate research

P.C.S. Devara^*, M.G. Manoj

Indian Institute of Tropical Meteorology, Pune 411 008, Maharashtra, India

10.1016/j.partic.2012.07.006

Volume 11, Issue 1, February 201, Pages 25-33

Received 14 October 2011, Revised 26 April 2012, Accepted 4 July 2012, Available online 4 January 2013.

E-mail: devara@tropmet.res.in; devara7@gmail.com

Highlights

► Lidars and solar radiometers at IITM were applied to study the aerosol–cloud–climate interactions.

► Results reveal an interface between aerosols in the sub-cloud layer and cloud layer aloft.

► The interface indicates a strong interaction between aerosols and clouds on regional scale.

► The results are useful to delineate influence of aerosol on weather and climate on regional scale.

Abstract

Aerosols affect clouds in two broad ways: (i) presence of more number of aerosols leads to formation of more smaller droplets, and reduces coalescence, resulting in brighter clouds that reflect more solar energy back to space, hence they contribute to cooling of the Earth's surface and (ii) numerous smaller cloud droplets tend to reduce precipitation and change the extent of cloud cover and increase cloud lifetime and albedo. One of our recent studies on aerosols over the Indo-Gangetic Plains (IGP) relative to the pristine oceans to the south of Indian Ocean showed that highly absorbing aerosols could potentially lead to the revival of active condition preceded by long break. The absorption of solar radiation by aerosols such as black carbon and desert dust produces surface cooling and local stabilization of lower atmosphere. This stability effect is overcome by the enhanced moisture convergence due to the meridional gradient of aerosol-induced heating. In some other studies, we showed association between cloud thickness and cloud to sub-cloud ratio (SCR), aerosol variability (in terms of aerosol optical depth and aerosol index) and monsoon precipitation and climate over regional scale. This paper provides an overview of some salient results that have been obtained from the studies conducted, using the ground- and space-based active and passive remote sensing techniques, at the Indian Institute of Tropical Meteorology (IITM), Pune, India in the recent decade.

Graphical abstract

Keywords

Aerosols; Clouds; Lidar; Solar radiometry; Radiation; Satellites

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