Future climate of Bangladesh

The global climate is changing, and Bangladesh is not spared. Bangladesh Meteorological Department (BMD) and Norwegian Meteorological Institute (MET Norway) have collaborated since 2011, and in 2016 we co-published “Climate of Bangladesh”, and in 2024 we published “Changing climate of Bangladesh”. The same cooperation has resulted in a new report that will be published in the June of 2025 named “Future climate of Bangladesh”. The new report goes beyond the baseline of today's climate and detected changes in the Bangladeshi climate, focusing on the future climate of Bangladesh as described in climate projections.

The main objective of this study is to establish a common data set for studies of the potential effects of climate change on Bangladesh in this century, and thus establish a common ground for climate adaptation. To achieve this we analysed the NEX-GDDP-CMIP6 dataset for a region covering Bangladesh. In this we uncovered that some of the models had a clear bias for the region, these models were excluded from the rest of the study, and thus left an ensemble of 23 models for the study. There are two major choices one has to perform before analysing the future climate data: Choice of scenarios and time periods. The chosen scenarios are: SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 thus including both extreme low end scenarios and high end scenarios, with two more interim scenarios. For time periods the following was chosen: Historic reference 1985-2014, Near future 2041 - 2070, and Far future 2071 - 2100.

The NEX-GDDP simulations show a warming in all seasons, with an increase in the daily mean temperature of +1 ℃ to +2 ℃ by the middle of the century (2041 - 2070) and +1.5 ℃ to +4.5 ℃ by the end of the century (2071 - 2100), depending on the season and region, assuming the high emission scenario SSP3-7.0 The number of days of heat waves (daily maximum temperature exceeding 36 ℃) is expected to increase considerably spreading out from the pre-monsson season to all season.  

Besides temperature and precipitation indexes a literature review on sea level rise in the bay of Bengal was included, and some information on impact on e.g. agriculture and health was included. These examples of impact should be considered exactly this, examples on impacts.