Project Motivation

Why do we study Hurricanes?

Hurricanes are among the costliest natural hazards in the United States, Caribbean and Central America causing large scale flooding, storm surges and incredible winds. Large hurricanes, such as Hugo (1989), Andrew (1992), Katrina (2005), and most recently Sandy (late October 2012) resulted in billions of dollars worth of damage and considerable loss of life. Hurricane Sandy is the largest hurricane on record and the 2nd costliest after Katrina, having caused an estimated $50 billion in damages. Climate scientists have identified several environmental factors associated with climate change that may have contributed to the damaging effects of this super storm. Sea level rise of 30 centimeters since 1900 may have increased storm surges, warmer North Atlantic waters most likely contributed additional moisture to the storm, and high pressure over Greenland along with repositioning of the jet stream may have impeded the usual eastward trajectory of the storm causing it to inflict more damage on the US eastern seaboard. It is predicted that hurricane frequency and intensity will increase with climate change and Hurricane Sandy may provide a glimpse as to what the future holds. The HURRICANE Project aims to improve our understanding of long term mechanisms controlling hurricane activity and, in doing so, increase our ability to predict future variability.

Hurricane Sandy from Satellite
Above, satellite image of Hurricane Sandy (Oct 2012) courtesy of the NASA GOES Project. The unprecedented size (2000 miles) of this super storm was the result of a Category 1 hurricane intensifying as it merged with a cold front to the northwest. Before reaching the US eastern seaboard, Sandy struck several Caribbean islands including Turks and Caicos Islands situated on the northern edge of the Caribbean Basin and one of the two HURRICANE Project field sites.

Why reconstruct past hurricane activity?

A reliable instrumental record of hurricane activity extends back little more than 60 years and therefore does not provide adequate information for climate modellers attempting to predict future risks. Furthermore hurricane activity, including the frequency and intensity of devastating category 4 and 5 storms, has increased dramatically in the last 15 years. A rise in sea surface temperatures in the cyclone genesis zones of the Atlantic Ocean potentially linked to anthropogenic global warming may be to blame.

However, some of this recent increase in activity may be due to long-term natural climate variability, but this cannot be assessed using the existing short instrumental and documentary records. By reconstructing past hurricane activity the relationships between hurricane activity and climatic parameters can be studied and questions and debates regarding the causes of increasing activity may be resolved.

Hurricane Wilma over Central America
Above, satellite image of Hurricane Wilma (2005) courtesy of NASA/GSFC showing the extensive geographical coverage of a single storm. This was a Category 5 hurricane that struck the Yucatan Peninsula and was one of the costliest in history.

Graph of hurricanes versus major hurricanes 1944-2008
Left, figure from the NOAA’s National Climate Data Centre (NCDC) showing the increase in Atlantic hurricane activity (relative to the long-term mean) since 1995. Another active phase between 1945 to 1970 is also visible in the diagram. Until the HURRICANE project can extend this record, it’s not possible to statistically evaluate whether the current activity increase is anomalous (and potentially responding to the recent global warming trend) or is part of a natural multi-decadal periodicity.