References

ANGEO

Annales Geophysicae

ANGEO

Ann. Geophys.

1432-0576

Copernicus Publications

Göttingen, Germany

10.5194/angeo-32-175-2014

Signatures of Rossby wave modulations in aerosol optical depth over the central Himalayan region

Phanikumar

D. V.

¹ Niranjan Kumar

² Shukla

K. K.

¹ ³ Joshi

¹ Venkat Ratnam

⁴ Naja

https://orcid.org/0000-0002-4597-1690

¹ Reddy

⁵

Aryabhatta Research Institute of observational Sciences, Nainital, India

Masdar Institute of Science and Technology, Abu Dhabi, United Arab Emirates

Pt. Ravishankar Shukla University, Raipur, Chhatisgarh, India

National Atmospheric Research Laboratory, Gadanki, India

Department of Physics, Yogi Vemana University, Kadapa, India

21 02 2014

32 2 175 180

2014

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://angeo.copernicus.org/articles/32/175/2014/angeo-32-175-2014.html

The full text article is available as a PDF file from https://angeo.copernicus.org/articles/32/175/2014/angeo-32-175-2014.pdf

Long-period modulations are shown in aerosol optical depth measured by the Microtops II Sun photometer over a high-altitude site the central Himalayan region (Nainital, 29.4° N, 79.5° E, 1958 m a.m.s.l.) for the first time. Fourier analysis of aerosol optical depth showed dominant 25–45 day oscillations observed in MODerate-resolution Imaging Spectro radiometer data. Further, a Hovmiller diagram showed westward (northward) propagation at a different longitude (latitude), confirming that the modulations are associated with Rossby waves. It is also shown that the Rossby wave amplitude causes an additional warming of 4.16 ± 0.98 W m<sup>−2</sup> over the observational site. Hence, the present study illustrates the importance of wave-induced aerosol dynamics and the corresponding radiative effects.

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