Analysis of climate change and future projection of rainfall, temperature, and potential evapotranspiration in Riam Kanan catchment area, Banjar Regency, South Kalimantan

Climatic conditions in Indonesia warm up indicated by the increasing of the average annual temperature by 0.3°C. This may cause higher water evaporation and increased rainfall intensity. Changes in rainfall patterns shift the start of the rainy season to be slower and end faster. These changes the dry season to become longer with shorter time intervals. In case of dam operation, dam manager needs to adapt the effects of climate change. This paper presents trend and future projection in Riam Kanan Catchment Area, Banjar Regency, South Kalimantan. Climate change historical trend analysis was carried out with the observation data used were rainfall and maximum temperature from BMKG climatology station, Banjarbaru Station, in the period 1983 - 2017. Future projection analysis was carried out by using RCP2.6 and RCP8.5 scenario data for projecting rainfall and temperature in the period 2018 - 2100. The result shows that the rainfall, maximum temperature, and evapotranspiration trends in Banjarbaru from 1983 - 2017 were not too significant by +0.1 mm, -0.5°C, and +0.1 mm. While the projection of RCP2.6 and RCP8.5 scenario shows increase by +0.1 mm, +0.1°C, +0.1 mm and by +0.1 mm, +3.3°C, and +0.1 mm. Keywords: Climate Change, Trend, Rainfall, Temperature, Evapotranspiration, RCP 2.6, RCP8.5