Tropical Cyclones: Impacts, the link to Climate Change and Adaptation

COP23 briefing – Following the string of high intensity tropical cyclones in the Atlantic basin in 2017 and the devastating impacts on Small Island Developing States (SIDS), a number of questions have been raised about linkages between these cyclones and climate change. This briefing provides clarity on scientifically-supported connections between existing tropical cyclones and climate change. The briefing also summarises how climate change may affect tropical cyclones at increased global mean temperatures in the future and provides a summary of the observed socio-economic impacts of these extreme events on SIDS.


Key Findings

  • The Atlantic Hurricane season brought horrific destruction over the Caribbean. In Barbuda, over 90% of structures were destroyed, resulting in the island being completely uninhabited for the first time in 300 years. Across the Caribbean the economic costs of tropical cyclones amount to 2% of GDP annually since the 1950.
  • The South Pacific has recently been hit by particularly destructive cyclones like Winston and Pam. Estimated economic cost of Cyclone Pam in Vanuatu across all sectors was approximately 64% of the country’s GDP in 2016. In Fiji, Cyclone Winston displaced over 130,000 people.
  • Attribution of tropical cyclones to climate change is difficult. However, a robust increase of the most devastating storms with climate change is evident. Under 2.5°C of global warming, the most devastating storms are projected to occur up to twice as often as today.
  • The climate hazard posed by cyclones is further intensified by increasing risks of flooding through heavier precipitation and sea level rise as a result of climate change.
  • The capability of many Islands to adapt to tropical cyclones is limited and such events can further erode their capacity to adapt to climate change impacts. The Loss and Damage inflicted by tropical cyclones, in particular on small island states, needs to be recognized and adequate support needs to be provided by the international community.
  • Post-disaster investment needs to be ambitious in scale and scope, supporting the transition to resilient, low carbon societies.

Socio-economic Impacts of Tropical Cyclones on SIDS

Tropical cyclones, also referred to as hurricanes or typhoons, are particularly significant hazards for SIDS. Large cyclones often encompass entire islands, affect significant percentages of the population and have substantial socio-economic impacts at the national scale, making SIDS one of the most exposed groups to these extreme eventsi . Cyclones have long-term negative effects on economic growth, particularly for small states and islands, with countries taking over 15 years on average to fully recover from these shocksii . For Pacific SIDS, tropical cyclones have resulted in an estimated average annual loss of US$180million for the past 50 yearsiii . Across the Caribbean, the economic costs of tropical cyclones have averaged approximately 2% of GDP annually since the 1950s, a conservative estimate given the likelihood of considerable underreporting of damagesiv . In addition to economic losses, tropical cyclones also have significant environmental implications, including damages to coral reefs which provide critical ecosystem services including coastal protection from storms. More frequent tropical cyclones also result in increased loss and damage since affected areas, particularly in developing countries, have insufficient time and resources to recover between events. In the Pacific, there have been a number of intense tropical cyclones that have resulted in significant loss and damage for island states in recent years. In February 2016, Cyclone Winston was recorded as one of the largest and most intense tropical cyclones in the Southern Hemisphere and had severe impacts throughout the South Pacificv . In Fiji, over 60% of the population was affected with 22% of the nation’s housing either destroyed or damaged and over 130,000 people being displacedvi. Destruction of approximately 500 schools prompted Fiji to seek an emergency assistance loan of US$50million to assist in reconstruction effortsvii. Cyclone Winston’s path resulted in two separate interactions with Tonga, where more than half of the island’s crops were damaged. Cyclone Pam, in 2015, affected over 70% of the population in Vanuatu, displaced 65,000 people and resulted in 11 deaths and over 17,000 buildings being damaged or destroyedviii. The estimated economic cost of Cyclone Pam on Vanuatu across all sectors was approximately 64% of the country’s GDP. In 2013, Typhoon Haiyan, another high intensity cyclone, had devastating impacts in the Philippines in particular. The typhoon resulted in over 6,000 casualties and had effects on approximately 16 million people in over 44 provincesix . Over 4 million people were displaced from their homes and approximately 1.1 million houses were either totally or partially damaged.