Climate change fuels surge in Caribbean cyclones, study finds
Scientists have discovered that tropical cyclones in the Caribbean region are becoming more frequent, which may be related to global warming. Research conducted in the Great Blue Hole in the Caribbean Sea reveals an unexpected trend.
Researchers examined sediments from the large coral reef sinkhole in the Caribbean Sea. The dark-blue Great Blue Hole, located about 50 miles from Belize, is situated in the middle of Lighthouse Reef atoll. This massive underwater sinkhole was formed as the sea level rose during the last ice age, approximately 10,000 years ago. It resembles a deep underwater well, around 407 feet deep and 984 feet wide. The latest sediment research from inside shows that the frequency of tropical cyclones is increasing with the changing climate. The results were published in the scientific journal "Geology".
What are the causes of the increase in the number of tropical cyclones?
Dominik Schmitt from Goethe University in Frankfurt, the lead author of the study, emphasizes that the frequency of cyclones has increased especially in the last two decades, which is clear evidence of the impact of contemporary global warming.
"A key finding of our study is that the regional storm frequency has increased continuously since 5,700 years B.P. [...] Remarkably, the frequency of storm landfalls in the study area has been much higher in the last two decades than in the last six millennia — a clear indication of the influence of Modern Global Warming," Schmitt told Live Science.
The core from inside the Great Blue Hole, the longest storm record
Tropical cyclones are intense, rotating low-pressure systems that can cause strong winds, heavy rains, and storm surges. They form over warm ocean waters. To learn more about these storms over a long time span, scientists extracted a sediment core from the bottom, 410 feet deep, of the Great Blue Hole.
The researchers describe this sediment core, measuring 98 feet long, as the longest continuous record of tropical storms in this region. By analyzing the sediment layers in the core, scientists could determine the number of tropical cyclones that occurred over the last 5700 years. Two fair weather sediment layers are typically deposited each year, allowing researchers to count the years like tree rings and discern when storm sediment layers were deposited. Scientists found that the frequency of tropical cyclones increased since we began burning fossil fuels during the industrial revolution.
Researchers discovered that in the last 20 years, the region experienced nine cyclones, which is a much higher number than in the previous six millennia. Schmitt notes that this increase may be connected to the southern migration of the Intertropical Convergence Zone (ITCZ), which affects the development of cyclones in the Atlantic region.
What does the future hold for the Caribbean region?
Scientists predict that by the end of the year 2100, up to 45 tropical storms and hurricanes may hit the Caribbean. Schmitt emphasizes that such a high number is unprecedented in the last 5.7 thousand years. The cause of this phenomenon is not natural climate changes, but advancing global warming, which leads to rising sea surface temperatures and intensification of La Niña events.
In their view, the increase in the number of tropical cyclones in the Caribbean region is a serious challenge that requires further research and measures to mitigate the effects of climate change.
