When do people migrate?

Sudden-onset climate hazards

Sudden-onset disasters impact people’s lives profoundly, often without warning, making the most basic of needs difficult or impossible to meet for entire communities. There are many different examples of how climate-related floods, hurricanes, wildfires and other sudden disasters have resulted in food insecurity. Floods affected food security, for example, in several locations in Africa between 2009 and 2020. In some countries of South Asia (such as Bangladesh, India and Pakistan), extreme floods are becoming more frequent and are expected to increase in magnitude as well, causing heavy damage to rice plantations, affecting mostly vulnerable minorities of the population.

In 2022, Pakistan suffered what the Prime Minister called the worst floods in its history, destroying thousands of hectares of farmland, significantly impacting food production in the country and driving almost a quarter of that year’s global disaster displacements. In Nigeria, a study revealed that floods increased the number of food insecure households by 92.8 per cent, turning communities into food insecure sites, further delaying developmental goals. In Afghanistan, a study found similar results, suggesting that increased exposure to flooding decreased calorie and micronutrient consumption, with other associated impacts on household income even after the flooding event.

Hurricanes have also been associated with a rise in food insecurity in Haiti, with severe impacts being correlated with moderate to severe household hunger. In the United States, hurricane Harvey had a impact on food insecurity, with different groups affected differently; in particular, it had a stronger impact on displaced persons. Surveys in Ghana have also highlighted the impact of wildfires on food insecurity, both in terms of transitory food insecurity in the lean season following a crop-destroying wildfire, and in the long term, through negative effects on soil productivity. In Sahelian countries such as Mali, Senegal and Burkina Faso, rainfall variability and the early cessation of rainfall are linked to food security threats and food deficits.