Impacts of Land-Use/Land-Cover Change and Climate Change on the Regional Climate in the Central Vietnam

Nowadays, it is widely accepted that both elevated greenhouse gas (GHG) concentration as well as land-use/land-cover change (LULCC) can influence the regional climate dynamics. It is a matter of fact that changes in the land use/land cover are often ignored in long-term regional climate projections. Even worse, often an outdated (RCM default) LU map is applied for modeling. In the framework of the LUCCi project, we applied the Weather Research and Forecasting Model WRF in combination with an updated LULC map to study (1) the impacts of an improved and updated Land-Use Land-Cover map on the regional climate in the VuGia-ThuBon basin in Central Vietnam; (2) the impacts separately of both the changed LU map and climate change (CC) on the regional climate; and (3) the sensitivity of land-use conversions in WRF simulations. It is found that the impacts of the outdated LU map exceed those of climate change, at least for the period 2001–2030. In addition, the deforestation scenario does not provide statistically significant signals of the most crucial surface climate variables, whereas the urbanization scenario provides evidence for a temperature signal (temperature increase) over the converted area, but no clear signal for precipitation is found.