Overall risks from climate-related impacts are evaluated based on the interaction of climate-related hazards (including hazardous events and trends) with the vulnerability of communities (susceptibility to harm and lack of capacity to adapt), and exposure of human and natural systems. Changes in both the climate system and socioeconomic processes -including adaptation and mitigation actions- are drivers of hazards, exposure, and vulnerability (IPCC Fifth Assessment Report, 2014).

This section provides a summary of key natural hazards and their associated socioeconomic impacts in a given country. It allows for a quick assessment of most vulnerable areas through the spatial comparison of natural hazard data with development data, thereby identifying exposed livelihoods and natural systems.

Natural Hazard Statistics

The charts provide overview of the most frequent natural disaster in a given country and understand the impacts of those disasters on human populations.


Climate change is now recognized to have a significant impact on disaster management efforts and pose a significant threat to the efforts to meet the growing needs of the most vulnerable populations. The demands of disaster risk management are such that concise, clear, and reliable information is crucial. The information presented here offers insight into the frequency, impact and occurrence of natural hazards.

Natural Hazard / Development Nexus

Understanding natural hazard occurrence as well as historical climate conditions, in relation to development contexts, is critical to understanding a country’s historical vulnerability. This tool allows the visualization of different natural hazards or historical climate conditions with socio-economic and development datasets. Select the Development Context and either a Natural Hazard or Climate Condition and overlay horizontally by sliding the toggle left or right to gain a broader sense of historically vulnerable areas.



Data presented under Historical Climate Conditions are reanalysis products derived from ERA5-Land data. ERA5-Land is a global land-surface dataset at 9 km resolution, consistent with atmospheric data from the ERA5 reanalysis from 1950 onward. Climate reanalyses combine past observations with models to generate consistent time series of multiple climate variables. They provide a comprehensive description of the observed climate as it has evolved during recent decades, on 3D grids at sub-daily intervals. 

This data has been collected, aggregated and processed by the Climate Resilience Cluster of the European Space Agency’s (ESA) Earth Observation for Sustainable Development (EO4SD) initiative.

Key Vulnerabilities

Sea level rise threatens low-lying coastal Sierra Leone; particularly vulnerable are the communities of Kroo Bay and Moa Wharf. Increased coastal flood events, coastal erosion, reduction in fresh water quality, population displacement, loss of property, reduction in groundwater resources, and reduced agricultural potential for coastal areas (e.g. mangroves) are expected impacts. Changes in flooding, rainfall patterns, and drought will also adversely affect human health by increasing the likelihood of particular diseases (e.g. cholera, diarrheas). Floods regularly affect Sierra Leone during the rainy season due to heavy precipitation and from storm surges along the coast. These events take a toll on agricultural production, infrastructure, people’s homes, public health and biodiversity along the coast.

Sierra Leone is exposed to various diseases that are influenced by climatic and environmental factors that may be enhanced due to climate change. For example, cholera outbreaks are associated with heavy rainfall in West African countries, and projected increases in precipitation in this region are likely to increase the frequency of outbreaks. Storms and in particular Squall Lines, which bring thunderstorms and high winds, are a recurring natural hazard that affect Sierra Leone in the pre monsoon season (April to June). These storms often disrupt communications and transportation nationwide, damage people’s homes and agriculture, and cause coastal erosion. Increased heavy rainfall events and sea level rise may exacerbate these events causing flooding to become more frequent, especially along the coast. Sea level rise will cause the coastal regions of Sierra Leone to experience more frequent coastal flooding events, and an increase in average precipitation and heavy rainfall events may induce more flooding and increase streamflow rates. Additionally, flooding may increase the likelihood of waterborne diseases, especially in concert with unsafe drinking water.

Global mean sea level rise is accelerating and in order for Sierra Leone to reduce its risk to rising seas, adaptation strategies that focus on establishing a national sea level observing system, coastal management systems, coastal protection, delineation of flood and erosion hazardous areas, sand and gravel mining, and education and research will further alleviate risks posed by rising seas. Adaptation strategies will be imperative to reduce the populations’ vulnerability to disease outbreaks, some of these priorities include: improvement of health delivery services, improved supply of safe drinking water and sanitation, increased immunizations, and increasing funding to the health sector. Development of an early warning system for storm events, strengthening meteorological and hydrological institutions through the use of Radar and satellite data, re-engineering of all-weather roads, and coastal protective barriers would decrease the populations’ risk to storms in the future. Key adaptation strategies aim to construct coastal defense systems, development of a sea level rise monitoring system, improved sanitation, increased access to safe drinking water, and the development of an early warning system for extreme weather events. These strategies will help reduce the vulnerability and risks posed by floods to the population.