Discovering Secrets in Blue Holes

By Sydney O’Brien, Wheaton College 

Blue holes are complex underwater structures that have been known to reach up to 300 meters across and 125 meters deep. The largest blue hole is located in Belize and is home to many species including Caribbean reef sharks and giant groupers. Blue holes are complex ecosystems, and before modern technology little was known about these holes, some even thought they could be home to sea monsters! Today we know these holes are large underwater sinkholes that contain complex cave systems. Many divers attempt to navigate these cave systems. Dahab’s blue hole in the Red Sea is unfortunately known as the “divers cemetery” due to how easily divers get lost in these systems and can not resurface in time. However, for all of the mystery and danger of these sinkholes, there is just as much to be gained through researching them. 

Blue holes carry inside of them a vast amount of history. They began their life on dry land during the last ice age and upon sea levels rising they filled. Hidden inside these blue holes is a vast array of life, but many researchers are interested in the non-living data these holes contain. Blue holes can depict evidence of hurricanes from the past, even going back thousands of years. From collecting sediment deposits scientists can reveal layers of debris from various time periods and storms, which shows frequency or severity of storms over the years. The samples in the blue holes are pristine compared to other locations because they are a large pit which traps the samples and allows little to no movement from wind or waves. This information can be valuable in determining climate changes impact on weather patterns such as hurricanes, and perhaps give a better understanding of the natural occurrence of these storms. 

With global temperatures rising it is thought that either more hurricanes will occur, or the hurricanes will become more severe. By comparing data from today with temperatures and weather patterns from the past, as well as the sediment data from the blue holes, perhaps we can begin to piece together upcoming weather patterns and prepare for storms to prevent heavy damage to coastal communities.