Solar activity and Indian weather/climate

Abstract

The literature on influences of solar activity on the Indian weather and climate is reviewed since the discovery of sunspot cycle. Fluctuations in solar activity are undoubtedly a factor affecting weather and climate. Although the results of some of the studies are conflicting, Indian weather and climate is, in general, inversely related to sunspots. However, the areal extent of floods in India seems to expand and contract in phase with the Hale double sunspot cycle, suggesting that the flood rhythm is in some manner controlled by long-term solar activity related to snlar magnetic effects. All the evidences of solar influences:on weather and climate may have practical implications in improving long-range forecasting of weather and climate, once the physical coupling mechanisms and their modification by other factors are clearly understood. Some of the promising plausible physical mechanisms for explaining solar effects on weather and climate arc also discussed.

Sensitivity analysis of vegetation indices to drought over two tallgrass prairie sites

“…However, NDVI has been the most popular and extensively used satellite-based index for drought monitoring over the past decades. Numerous studies have analyzed the relationships between NDVI and rainfall across geographical areas and vegetation types (Bhalme et al, 1981;Boschetti et al, 2013;McKee et al, 1993;Van Rooy, 1965). In the central and northern Great Plains grasslands, growing season rainfall, growing degree days and potential evapotranspiration exerted strong control over grassland productivity (Yang et al, 1998).…”

“…Understanding the need to quantify drought severity, researchers have developed several methods to assess and diagnose different droughts. Meteorological drought indices (Rainfall Anomaly Index, Bhalme and Mooley Drought Index, Drought Severity Index, Standardized Precipitation Index) were solely based on meteorological data such as precipitation and temperature (Bhalme et al, 1981;McKee et al, 1993;Van Rooy, 1965 moisture and evapotranspiration deficit (Hollinger et al, 1993;Narasimhan and Srinivasan, 2005;Palmer, 1965), while hydrological drought indices (Palmer Hydrological Drought Index, Surface Water Supply Index, Reclamation Drought Index) were based on a water balance model (Shafer and Dezman, 1982;Weghorst, 1996).…”

Influence of cosmic-ray variability on the monsoon rainfall and temperature

“…see Jagannathan and Bhalme, 1973;Bhalme et al, 1981;Hiremath and Mandi, 2004;Bhattacharya and Narasimha, 2005;Badruddin et al, 2006Badruddin et al, , 2009.…”

Influence of cosmic-ray variability on the monsoon rainfall and temperature

“…On shorter time scales (decadal to inter annual) too, solar activity/cosmic ray intensity influence on the rainfall changes in Indian summer monsoon have been suggested, but with conflicting results (e.g. see Jagannathan and Bhalme, 1973;Bhalme et al, 1981;Hiremath and Mandi, 2004;Bhattacharya and Narasimha, 2005;Badruddin et al, 2006Badruddin et al, , 2009.…”