The purpose of this study is to extract climate element affecting coffee yield by growth period using data of production and cultivation area of coffee and climate data for 2000-2018. During the analysis period, the production of coffee in Vietnam has been consistently increasing, but Ðăk Lăk in the Central Highlands, the main cultivation area for coffee production, has recently stagnated in the trend of increasing yield. The yield of Lâm Đồng, located in the relatively highlands of the Central Highlands, is steadily increasing. Coffee yields of Ðăk Lăk is negatively correlated with the temperature during flowering period, and is also significantly negatively correlated with the maximum temperature and precipitation during the late growing period. On the other hand, Lâm Đồng, located at a relatively high altitude, has a positive correlation with temperature during the late growing period. It is analyzed that the lower the altitude, the higher the temperature, the lower the coffee productivity due to the high temperature appearance, and the lower the low temperature appearance in the high altitude region.

The purpose of this study is to examine the effect of climatic elements on the arabica coffee yield during the various growth stages of coffee plant for the period of 1996-2017 over Costa Rica. For the future scenario, change rate of arabica coffee yield is also estimated using the data of production and cultivated area. The cultivation area and the yield of arabica coffee has been decreasing since the 1990s in Costa Rica. The decreasing trend in arabica coffee yield could have a negative effect on Costa Rica’s coffee industry in the future. During the dry season, the yield of arabica coffee has significant negative correlation with precipitation at the stage of flowering in the month of February. In case of wet season, coffee yield and temperature were negatively correlated while precipitation showed positive association with coffee yield at the stage of growing period in the month of August. However, the observation revealed the excessive precipitation drastically reduced arabica coffee yield in 2013 during August, the month of wet season. According to the RCP 4.5 and RCP 8.5 climate change scenarios, due to high temperature and fluctuated precipitation the yield of arabica coffee is unstable and the future of coffee industries is also insecure.