Systemic Vulnerability and Adaptation Traps in The Gambia’s Agricultural Sector under Climate Change ()
The Gambia’s agricultural sector, which is predominantly rain-fed and employs 70% of the labor force, is exceptionally vulnerable to climate change. This study assesses the impacts of projected climate change on crop water requirements and the broader agro-ecological system to inform national adaptation planning. A hybrid modeling framework is employed that integrates a biophysical crop water model (CROPWAT 8.0) with a system dynamics (SD) model. The CROPWAT analysis uses CMIP6 climate projections for two Shared Socioeconomic Pathways (SSP2-4.5 and SSP5-8.5) for the mid-century period (2040-2059) to quantify changes in reference evapotranspiration (ETo) and crop water requirements (CWR) for five major crops. The SD model simulates the long-term (2020-2060) behavior of the interconnected agricultural, water, and socioeconomic subsystems under three policy scenarios. These are the Business-as-Usual (BAU), Infrastructure Investment, and Crop Diversification scenarios. Results from the CROPWAT model indicate a significant increase in atmospheric water demand, with ETo rising by 6.3% - 7.4% and CWR for all crops increasing by 3.3% - 4.3%. The net irrigation requirement for rice, an important staple, is projected to increase by a substantial 14.9% - 21.9%. The SD model reveals a concerning long-term decline in the food security index and average farmer income across all scenarios, even with policy interventions. These interventions provide only marginal improvements over BAU, highlighting a systemic “adaptation trap” where climate-induced poverty suppresses the capacity to invest in resilience. The findings demonstrate that incremental, field-level adaptation strategies are insufficient to counter the systemic pressures of climate change and population growth. This study concludes that a shift towards impactful, national-level policies focused on structural economic change and large-scale water management is imperative for building long-term resilience in The Gambia.
