Critical analysis of temporal climate change and ensuing frequency of crop yield constraining temperatures

Abstract

Critical analysis of magnitudes andtrends of temporal changes in maximum (Tmax) and minimum (Tmin) temperatures as well as rainfall during three time series i.e. past (observed data, 1970-1990), present (observed data, 1989-2018) and future (bias corrected modelled data, 2021-2050) reveals that on the whole, inter–series mean of all the three climate parameters increased, and variation decreased in future time series. The magnitude of these trends varied with the model as well as scenario; was highest in RCP 8.5 scenario. Intra-series trends at annual and seasonal scales are dictated by inconsistent monthly trends. This study also adds that decline incrop yields of rice-wheat system with warming in future can be ascribed to increased frequency of days having yield constraining temperatures (above ceiling and below critically low during crop growth and reproduction stages) rather than their elevated magnitudes only as anticipated previously.

Keywords

• Climate parameters, RCP, bias correction,time series trends, rice-wheat system