Tropical Cyclones

A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain. They form over warm tropical or subtropical waters and derive their energy from the evaporation of water from the ocean surface, which then condenses to form clouds and rain when it reaches cooler air. Tropical cyclones are classified based on their intensity, with tropical depression being the weakest form and hurricane (in the Atlantic and Northeast Pacific), typhoon (in the Northwest Pacific), or cyclone (in the South Pacific and Indian Ocean) being the strongest form.

A tropical cyclone is one of nature's most powerful and destructive forces. Storms, including tropical cyclones and hurricanes, were second only to earthquakes in terms of fatalities, killing 233, 000 people. In the United States, tropical cyclone is the most costly type of natural hazard. Between 1980 and 2002, tropical cyclones caused $1,333.6 billion in damage, with an average cost of $22.2 billion per event -- the highest average event cost among all natural hazard types.

This article talks about the change in tropical cyclone with climate change. https://www.climate.gov/news-features/blogs/beyond-data/2023-historic-year-us-billion-dollar-weather-and-climate-disasters.

Hurricane (Source: The Orlando Real)

Impacts

The primary hazards from tropical cyclones (which include tropical depressions, tropical storms, and hurricanes) are storm surge flooding, inland flooding from heavy rains, destructive winds, tornadoes, and high surf and rip currents.

• Storm surge is the abnormal rise in water level caused by a storm's winds, which can exceed 20 feet in height and extend across hundreds of miles of coastline. When combined with the astronomical tide, this rise in water level is known as storm tide. Storm surge can push several miles inland, particularly along bays, rivers, and estuaries. The immense power of storm surge, coupled with large, battering waves, can lead to loss of life, destruction of buildings, erosion of beaches and dunes, and damage to roads and bridges along the coast. Historically, storm surge has been the leading cause of hurricane-related deaths in the United States. You may refer to CRL's storm surge wiki page for more detail.
• Inland flooding from heavy rainfall is the second leading cause of fatalities from landfalling tropical cyclones. Tropical cyclones often bring widespread, torrential rains exceeding 6 inches, which can lead to deadly and destructive floods. Such flooding can continue for several days even after the storm has dissipated. The amount of rainfall is not directly tied to the strength of a tropical cyclone but is influenced by the storm's speed, size, and the geography of the affected area. Slower-moving and larger storms tend to produce more rainfall, and mountainous terrain can further intensify rainfall from a tropical cyclone.
• Winds from a hurricane can destroy buildings and manufactured homes. Debris, such as signs, roofing material, and other items left outside can become flying missiles during hurricanes. Winds can stay above hurricane strength well inland. In 2004, Hurricane Charley made landfall at Punta Gorda on the southwest Florida coast and produced major damage well inland across central Florida with gusts of more than 100 mph.
• Tornadoes can accompany landfalling tropical cyclones. These tornadoes typically occur in rain bands well away from the center of the storm; however, they can also occur near the eyewall. Usually, tornadoes produced by tropical cyclones are relatively weak and short-lived, but they still pose a significant threat.
• The powerful waves produced by a tropical cyclone's strong winds can pose a significant hazard to coastal residents and mariners. When these waves break along the coast, they can produce deadly rip currents which can pull even the strongest swimmers away from shore. These waves can also cause significant beach erosion and damage to coastal structures, even at a large distance (e.g. more than 1000 miles) from the storm.

Data

Tropical cyclone datasets

Dataset	Description	Map viewer link	Data access link
HURDAT	A database for tropical cyclone historical data released by the National Hurricane Center (NHC). It is a detailed post-storm analysis of each tropical cyclone in the Atlantic basin and the North Pacific Ocean. It includes six-hourly updates on various aspects such as location (latitude, longitude), maximum winds, and central pressure of all known tropical and subtropical cyclones, Since 2004, the database also includes data on the size of these cyclones. This database is regularly updated as new analyses are reviewed. Other NHC data archive can be found here.		Access
HURSAT	Tropical Cyclone-centric satellite data		Access
IBTrACS	International Best Track Archive for Climate Stewardship (IBTrACS) project is the most complete global collection of tropical cyclones available. It merges recent and historical tropical cyclone data from multiple agencies to create a unified, publicly available, best-track dataset that improves inter-agency comparisons.	View	Access
NHC Active tropical cyclones	Real-time monitoring of currently active cyclones	View
NHC Forecast	Forecast of rainfall and wind speed of currently active cyclones	Rainfall, Wind speed
d4PDF	Database for Policy Decision Making for future climate change. A large ensemble of climate simulations at 60-km resolution and dynamically downscaled to 20 km. It is designed for climate change risk assessments in various research areas such as natural hazard, hydrology, civil engineering, agriculture, health, and insurance.		Access
HighResMIP	The High Resolution Model Intercomparison Project (HighResMIP) was an endorsed project under CMIP6, featuring simulations at higher resolutions than typical CMIP6 experiments. It spans the period from 1950 to 2050, with additional targeted experiments. Tropical storm tracks are calculated, which can be used to study changes in tropical cyclones under future global warming conditions.		Access

Other useful resources

• USGS Hurricane resources, including impacts on nonindigenous aquatic species
• Hurricane impacts on agriculture by USDA. Some local financial loss data is included.
• Hurricane Debby damage assessment aerial imagery
• The deadliest Atlantic Tropical Cyclones from 1492 to 1996
• National hurricane center includes a lot of useful information, including climatology, types of damage due to hurricane winds of each category, the costliest cyclones in the US history, summary of global and regional dynamical models for track, intensity, and wind radii.
• An interface for viewing, analyzing, and downloading the latest near real-time and disaster specific data products in GIS format by NASA
• Worldwide tropical cyclone centers