A study is carried out to understand whether the Indian summer monsoon rainfall variability is associated with the geophysical parameters over the Arctic region. The correlation analyses of the satellite-derived sea ice data for 29 years indicate that out of 9 sectors of the Arctic region, the Kara and Barents Seas sector's Sea Ice Extent (KBS SIE) during October has a strong relationship with the All-India Summer Monsoon Rainfall (AISMR) in the following year. This relationship is more pronounced for the extreme cases, which are identified as the drought or the excess monsoon years. Moreover, the composites of certain geophysical parameters over the Arctic also behave in tandem with the monsoon rainfall. In order to test the relationship of these geophysical parameters with the monsoon rainfall, a case of the recent drought of 2009 is independently evaluated. The results obtained in this study bring out that KBS SIE and some other parameters of the Arctic region can be used as potential predictors in the long-range forecasting of AISMR with a lead period of more than six months. A table indicating the qualitative forecast of the monsoon rainfall is presented on the basis of some parameters of the Arctic region. The mean sea level pressure anomaly tendency over northwest Europe during winter, which is one of the predictors used for forecasting the AISMR, is significantly correlated with the KBS SIE during the preceding October. As such, with the knowledge of October KBS SIE, this parameter can also be foreseen a few months in advance.

[1] Sea ice extent (SIE) over different sectors of Antarctica displays intra-seasonal and inter-annual variability. It is reflected in different atmospheric and oceanic parameters, which are characterized as the manifestation of Antarctic circumpolar wave (ACW). Due to its large areal extent, ACW is linked to the global climate. Another global phenomenon, which is instrumental for the well being of vast population of the Asian sub-continent, is the Indian summer monsoon season (June-September). The quantum of all India summer monsoon rainfall (AISMR) received during the season decides the overall economic health of the country with the extremes causing disastrous situation, in either way. In the present study, the cases of the excess monsoon and drought years of the recent decades are considered to determine the possible role played by the ACW in influencing the monsoon rainfall. The correlation analyses, carried out for a period of 26 years from 1980 to 2005, show that the SIE over the Bellingshausen and Amundsen Sea Sector (BASS) during the austral summer (October-December) has an inverse relationship with the AISMR of the following year. Further, it is revealed that the sea surface temperature and the upper tropospheric meridional transport of heat over the southeast Pacific, during the period preceding the monsoon season, show contrasting behavior with respect to the extremes of AISMR. These parameters bring out the role of both the oceanic and the atmospheric modes of the ACW in modulating the AISMR. The study has a potential application in forecasting of the monsoon rainfall a few months in advance.

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This study is aimed at evaluating the impact of non-conventional winds using data obtained by INSAT

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