Impact of climate variability on coffee yield in India—with a micro-level case study using long-term coffee yield data of humid tropical Kerala

Study on variability in area, production, and productivity of coffee in India during last decade indicates that area and production of coffee is increasing whereas yield of coffee is decreasing trend during the period 1990–1991 to 2015–2016. There was increasing trend of Robusta coffee and decreasing trend of Arabica coffee yields in India with three distinct periods due to climate change. Micro-level study was conducted on variability in yield of Arabica and Robusta coffee vis-à-vis climate change, variability of parameters like rainfall (RF), maximum temperature (Tmax), minimum temperature (Tmin), and mean relative humidity (RH) was undertaken with data recorded at Regional Coffee Research Station, Chundale, Wayanad, Kerala State. The yield data for 35 years (1980 to 2014) revealed that the yield of Robusta coffee was higher than that of Arabica coffee in most of the years due to favorable climate requirements in Kerala. There was increasing trend of yield of Robusta coffee in Kerala and decreasing trend of Arabica coffee. Blossom showers had significance influence in increasing the yield of coffee rather than total annual rainfall in Robusta coffee. El Niño events have little effect on coffee production in India in general, and out of 11 El Niño years, only 3 years coffee productivity was adversely affected. However, with respect to Kerala, Arabica yield was adversely affected in strong El Niño years, which was again confirmed with NDVI anomaly too.