Publications

Ojha, SP; Singh, R; Shukla, MV (2016). Algorithm for generating cloud-mask from multi-channel satellite data. QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, 142(696), 1351-1358.

Abstract
This article presents an algorithm for generating cloud-mask, over the ocean, from multi-channel satellite data. The algorithm is based on the assumption that, at any given instant of time, the observed radiances are a mixture of many Gaussians where each Gaussian mixture component is representative of a scene (clear or cloudy). The problem is attempted as one of the unsupervised clustering. The clusters in the data are separated using a Gaussian mixture model. The proposed algorithm is applied on INSAT-3D imager data and its performance is assessed by comparing the cloud-mask thus generated against the Moderate Resolution Imaging Spectroradiometer (MODIS) cloud-mask for forty selected days in the year 2014. The skill of the algorithm developed in this study is about 20% higher than the algorithm currently operational for generating the INSAT-3D cloud-mask. Due to the fact that currently geophysical parameter retrieval (e.g. sea-surface temperature) and data assimilation are performed in clear-sky regions, the developed algorithm will have large implications in retrieval and data assimilation studies.

DOI:
10.1002/qj.2738

ISSN:
0035-9009