The Importance of Studying Sinkholes

This is Jim Fiorendino, your host for on the ocean.

Researchers at Texas A&M University are analyzing sediments archived in blue holes and sinkholes throughout the Caribbean. The information contained within these sediments can be used to reconstruct storm patterns, regional precipitation, land use, and environmental change going back thousands of years.

The populations of the Caribbean are highly vulnerable to storm activity and changes in rainfall. Tropical cyclones are the costliest and deadliest recurrent natural disaster within the Caribbean basin and many of the coastal communities and inhabitants of the small island nations within the basin are dependent upon precipitation for potable water. It is predicted that 80% of the global population will face a shortage of potable water in the coming century, and that warming seas will lead to more frequent and more powerful storms.

Storm induced overwash may destroy crops and infrastructure and poison ground water for months. Drought has lasting effects on agriculture and negatively impacts tourism (which is an important part of many Caribbean economies). Understanding what conditions existed in the past, and what the driving forces were behind those conditions can help forecast future scenarios and possibly mitigate some of the damage caused by drought and tropical cyclones today.

Reconstructions have revealed drought intervals lasting for centuries that afflicted much of the Caribbean, while more extreme short-term deviations occurred in specific areas motivated by local factors. Tropical cyclone genesis, intensity, and track also seem to adhere to broad patterns in which active intervals in one locality may indicate reduced activity in another. Parsing these relationships from the sedimentological archive allows for the contextualization of the conditions observed today.

Through understanding groundwater patterns, past regional precipitation variability and tropical cyclone activity, we can begin to predict future conditions. Long-term trends in precipitation and prevalence of storms are driven by larger climate systems that may influence drought, storm activity, or flooding elsewhere on the globe. While a sinkhole may be a localized geologic feature, the story archived within the sediments may have both global and future implications.

This has been On the Ocean, a program made possible by the Department of Oceanography and a production of KAMU-FM on the campus of Texas A&M University in College Station. For more information and links, please go to and click “On the Ocean”.

Script Authors: Richard Sullivan, Annie Tamalavage, Tyler Winkler, and Pete van Hengstum