Links Between Global Climate Teleconnections and Indian Monsoon Rainfall

Abstract

The knowledge of teleconnections elucidates the mechanisms behind the local meteorological processes that are influenced by the ocean/atmospheric circulations, which operate at global scale. As the local meteorological variables such as regional temperature/rainfall and global climate signals possess multiscaling properties, it is highly desired to examine the teleconnections in multiple process scales rather than following conventional statistical correlation analysis and/or based on periodicity estimation. In this context, this chapter presents an investigation of hydroclimatic teleconnections of All India Summer Monsoon Rainfall (AISMR) with large-scale climate oscillations in a multiscaling framework by employing Hilbert–Huang Transform (HHT)-based Time-Dependent Intrinsic Correlation (TDIC) analysis. The study investigated the teleconnections of AISMR for the period 1950–2012, with the four global climate oscillations such as Quasi-Biennial Oscillation (QBO), El Nino Southern Oscillation (ENSO), Equatorial Indian Ocean Oscillation (EQUINOO), and Atlantic Multidecadal Oscillation (AMO) in different process scales. The study found that both the strength and nature of association between global climate oscillations and ISMR vary with process scale and there could be multiple switchovers in the character of such associations over the time domain.