Climate and cultivation in the Ganges-Brahmaputra-Meghna river delta

Geophysical, climatic, and socioeconomic conditions have made populations living in the Ganges-Brahmaputra-Meghna River delta especially vulnerable to climate change. This chapter explores the impacts and consequences of climate change for the GBM delta and how they affect the opportunities available to food producers. We review the prevailing scientific knowledge regarding alterations to temperature and precipitation regimes, increased riverine floods, intensified tropical storms and surges, and salinity intrusion, including their impacts on agriculture and aquaculture production and adaptation strategies that have been attempted. We also present an empirical case study of coastal Bangladesh that uses the Ricardian method to investigate the effect of these climate factors on agriculture and aquaculture. Higher summer temperatures and heat stress are detrimental to agriculture, but greater fall precipitation is beneficial by increasing irrigation input for dry winter crops. Aquaculture operations yield lower profits with greater spring precipitation. Agriculture is also sensitive to higher salinity and poor drainage. In contrast, aquaculture benefits from moderate salinity and is tolerant of high salinity. Both agriculture and aquaculture operations yield lower profits where exposed to storm surge inundation. Diversification into brackish water aquaculture exacerbates soil salinity and hinders staple rice cultivation in the long run, further compromising food security.