Climate change model predicts 33 % rice yield decrease in 2100 in Bangladesh

In Bangladesh, projected climate change is expected to increase food demands by more frequent and intense droughts and increasing temperatures. Few investigations have studied the impact of climate variability on future rice production. Previous investigations mainly checked the sensitivity of higher air temperature and higher atmospheric carbon dioxide on rice yields. Whereas in this study, we checked the combined effects of major climatic parameters on rice. The effects of climate change on yield of a popular winter rice cultivar in Bangladesh were assessed using the biophysical simulation model ORYZA2000. This model was first validated for 2000-2008 using field experimental data from Bangladesh, with a careful test of climate data on daily basis for station-wise and reanalysis datasets. The model performance was satisfactory enough to represent crop productions in nine major rice-growing districts. Then, simulation experiments were carried out for 2046-2065 and 2081-2100. Results show 33 % reduction of average rice yields for 2046-2065 and 2081-2100 for three locations. Projected rainfall pattern and distribution will also have a negative impact on the yields by increasing water demands by 14 % in the future. The model also showed that later transplanting will have less damage under the projected climate.