Climate change and urban pressures intensify flood risk on the Gulf of Guinea coast

In between 20– 22 June, the seaside areas of the nations surrounding the Gulf of Guinea, especially Côte d’Ivoire, Ghana, Togo, and Nigeria, experienced extremely extensive and extreme flooding following extreme and consistent rains. In numerous places, more than 140 mm of rain fell within less than 24 hours, frustrating natural drain systems and activating comprehensive flash floods.

The occasion belonged to a longer duration of heavy rains that has actually impacted West Africa for weeks, extending from Côte d’Ivoire to Nigeria, displacing numerous individuals and triggering extensive damage (The Economist, 2026. The rains at the end of June resulted in a series of fatal flash floods throughout the area from Lagos to Monrovia, immersing automobiles and getting rid of markets. A minimum of 34 individuals passed away in Ghana, where June rains reached its greatest level because 1995, while 5 deaths were reported in Togo (The Economist, 2026. The rainy season, which is anticipated to continue for a number of more weeks, raises issues that additional extreme weather condition and flooding might happen (The World, 2026. In Côte d’Ivoire, flooding has actually declared 59 lives given that May however the death toll might increase as search and rescue operations continue throughout the rainy season, which lasts from May through July and heavy rains might continue throughout July (The Guardian, 2026.

To examine to what level human-induced environment modification modified the possibility and strength of the heavy rainfall causing the serious flooding, scientists from Côte d’Ivoire, Ghana, Kenya, the Netherlands, Sweden, the United States and the UK carried out an attribution research study on the 3-day occasion of the heaviest rains in the most affected area (red box in figure 1).

Fig. 1: Accumulated rains over the gulf of Guinea Coast 20-22 June 2026 in TAMSAT.

Main Findings

• The floods impacted a really largely inhabited area where fast urbanisation and the growth of official and casual settlements into floodplains and conversion of natural plants to croplands have actually lowered natural drain capability and increased direct exposure to flooding. Population development is forecasted to continue its upward trajectory in this area, additional increasing direct exposure in the years to come.
• The flood effects extend far beyond the locations straight flooded. Disturbances to facilities, incomes, and farming can aggravate food insecurity, and infected water and harmed sanitation and health systems increase the threat of water-borne illness in the coming week and months, especially for kids and individuals with pre-existing health conditions. This year’s flooding belongs to a pattern of comparable floods that regularly happen in this area, wearing down individuals’s properties and capability to recuperate.
• The occasion is not uncommon in today’s environment, which is 1.4 ° C warmer than it would have been at the start of the commercial duration. A 3-day rains occasion of this magnitude is now anticipated to take place about when every 2-4 years in the research study area.
• To evaluate if human-induced environment modification affected the heavy rains in the research study area, we initially figure out if there is a pattern in the observations. Outcomes revealed that observed 3-day rains has actually increased in strength by about 23% over the research study area given that records started. Equivalently, an occasion like this has to do with 5 times most likely to happen today than it would have in a 1.4 ° C cooler environment. Unpredictabilities around these numbers are high and depend on which datasets are utilized.
• To measure the function of human-induced environment modification we likewise evaluate environment designs over the fairly little research study area. In general, the offered environment designs suggest just an extremely little boost in the possibility of an occasion such as the one under research study with about 4% boost in strength. While most of the designs reveal a pattern towards more severe rainfall occasions, they methodically undervalue the observed boost. While a lot of designs reveal a boost in 3-day rains, supporting the conclusion that the observed boost is attributable, self-confidence in the approximated magnitude of the associated modification is constrained by the designs’ restricted efficiency and by the reality that none were established or adjusted particularly for the African continent. Integrating design- and observation-based quotes to obtain a single quantitative attribution outcome is not significant.
• Under a future warming circumstance where the international temperature level is 2.8 ° C greater than pre-industrial levels, environment designs recommend that even wetter 3-day durations must be anticipated. Considered that these occasions are not uncommon today, this suggests they will prevail incidents, and the area requires to get ready for much heavier occasions than those observed in 2026.
• Research study has actually revealed that water level increase along the Gulf of Guinea coast has actually gone beyond the international average, intensifying the effects of significantly extreme rains. Together, these modifications are therefore driving higher flood threat along the Gulf of Guinea than would arise from rains surge alone, increasing threats to largely inhabited cities and crucial facilities.
• Floods and associated effects will continue to happen unless considerable efforts are made to minimize vulnerability and direct exposure to the floods. While the dominant type of flood adjustment in the area is physical facilities, a series of options is required to resolve the effects to facilities, health, financial losses, and displacement that arises from these floods. These can consist of increasing access to safe and cost effective real estate, enhancing drain and sanitation systems, imposing policies on much safer building and construction, enhancing early caution dissemination, and higher involvement of impacted neighborhoods in preparation.