Daily 1 km gridded temperature and precipitation in Bhutan

Gridded climatological data derived for Bhutan from internationally available data sets either come at very low spatial resolution, do not provide daily data or contain few in-situ measurements. We present a newly developed daily high-resolution (1 km) gridded data set for Bhutan covering the years 1996 to 2019 for precipitation and for maximum and minimum temperature (BhutanClim) and compare it with state-of-the-art global observation data sets. As input, we used quality controlled and homogenized data from up to 67 weather stations from the National Center for Hydrology and Meteorology of Bhutan (NCHM).

The spatial interpolation method of temperature is based on methods that have already been successfully implemented in Austria, Switzerland and Germany. It allows non-linear lapse rates and considers geographical obstacles in the interpolation. The new climatology benefits from the use of local measurements and shows plausible small scale spatial patterns. Compared to other available state-of-the-art data sets BhutanClim there are new features especially in the precipitation field: Some valleys in central Bhutan border a dry climate classification according to Köppen-Geiger.