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. And it allows quick evaluation 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
  • Recently a persistent drought has made an impact on agriculture and food production in Comoros by delaying fruit maturation, drying grasses, and reducing pasture area. Further, decreases in precipitation and prolonged droughts have led to water shortages, which is a concern for Comoros in the event of possible increased droughts in the future under climate change. River networks primarily supply the islands of Anjouan and Mohéli and decreases in rainfall could diminish the hydrographic network on these islands. 
  • Malaria is one of the main causes of death, hospitalization, and child mortality in Comoros and climate change is expected to increase its geographic reach into higher altitudes and enable a prolonged transmission season. Regions of the islands that receive the most precipitation and inundation are also susceptible to outbreaks in waterborne diseases. 
  • Heavy rains cause flooding of rivers, and in concert with deforestation also promote instability of the land, causing landslides and rock falls, especially on the islands of Anjouan and Mohéli. Additionally, devastating storm surges caused by heavy winds and sea level rise have caused severe inundation. In 2012, floods affected 65,000 people and damages cost Comoros an estimated US$18-20 million.
  • Cyclones threaten Comoros every year and in recent years, their occurrence has been trending upward. 2004 experienced particularly intense storms that caused significant damage and mortality. The year of 2013 was also a particularly severe year for cyclones in the region, with the islands of Comoros, Madagascar, Mauritius, Seychelles, and Zanzibar experiencing US$250 million in damage collectively. 

More information on natural hazards can be found at ThinkHazard.

  • Better management of water resources, an emphasis on water security and drought preparedness, increased access to potable water, conservation, and more efficient irrigation are needed to reduce the risks related to drought in the future.
  • Climate change will exacerbate sea level rise problems on water resources and efforts need to aim at developing island hydraulic systems, water treatment, conserving and restoring coastal and marine habitats to limit erosion, promoting the use of non-metallic local construction materials to limit beach and soil erosion, and the introduction of an early warning system to reduce the populations vulnerability to these risks posed by sea level rise and storm surge.
  • Proper water management in Comoros will help to reduce epidemic diseases as the climate changes, as well as outreach and education about proper water storage, sanitation, and best practices.
  • The fisheries sector and tourism industry are vulnerable from an economic standpoint and diversification of the economy in Comoros, such as strengthening infrastructure (e.g. telecommunication and power) and energy, could help reduce this particular vulnerability to climate change.
  • Protection of coastal areas, conservation of forests and soils, establishment of an early warning system, among other adaptation strategies will help to decrease future risks caused by floods in Comoros.