Sediment Samples From Great Blue Hole in Belize Show Hurricanes Are Becoming More Common in the Caribbean

The Caribbean Sea has always held mysteries—sunken ships, vibrant coral reefs, and natural wonders that defy explanation. One of the most stunning of these is Belize’s Great Blue Hole—a wide, dark circle in the ocean nearly 410 feet deep, surrounded by brilliant turquoise waters. Formed thousands of years ago, when rising sea levels submerged a limestone cave system, the Great Blue Hole is more than a mesmerizing dive spot—it’s a time capsule. Now, experts have dived deep into its depths and unraveled a discovery with profound implications for the region’s future, stated IFL Science.

In the summer of 2022, a team of researchers led by Goethe University Frankfurt drilled 30 meters (98 feet) into the sediment layers at the bottom of the Great Blue Hole. What they found wasn’t just geological history—it was a crystal clear record of tropical cyclones over nearly six millennia. The message it delivered was grave—hurricanes are becoming more frequent in the southwestern Caribbean, and the pace is picking up rapidly. Professor Eberhard Gischler shared, "Our results suggest that some 45 tropical storms and hurricanes could pass over this region in our century alone. This would far exceed the natural variability of the past millennia," stated Live Science.

Intriguingly, the sediment core, which acts like the rings of a tree, revealed 574 distinct storm layers—tempestites—formed when powerful waves carried coarse particles from the reef into the sinkhole during major storms. Dr. Dominik Schmitt, the study’s lead author, shared, "Due to the unique environmental conditions – including oxygen-free bottom water and several stratified water layers – fine marine sediments could settle largely undisturbed in the 'Great Blue Hole.' Inside the sediment core, they look a bit like tree rings, with the annual layers alternating in color between gray-green and light green depending on organic content…The tempestites stand out from the fair-weather gray-green sediments in terms of grain size, composition, and color, which ranges from beige to white," stated IFL Science.

Historically, between four and 16 tropical storms pass through this region each century. In the past 20 years, however, experts identified nine such events—more than double the historical rate. If that trend continues, the Caribbean is in for a stormier future than ever before. Schmitt remarked, "A key finding of our study is that the regional storm frequency has increased continuously since 5,700 years B.P. (before present)...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," stated Live Science.

Schmitt continued, "Over the past six millennia, between four and sixteen tropical storms and hurricanes have passed over the Great Blue Hole every century…The nine modern storm layers from the last 20 years indicate that extreme weather events in this region will become much more frequent in the 21st century…This high number is far in excess of what has been the case in the past 5,700 years," stated Live Science. The findings were published in the journal Geology and have already made waves in the climate science community.