Many remember Hurricane Bob. Most have heard about Hurricanes Donna and Carol. The hurricanes of ’44 and ’38 are well-known. But what about earlier storms? There must have been many through the ages for which there no record.
Jeffrey Donnelly, a scientist at the Woods Hole Oceanographic Institution recently looked for and found evidence of major hurricanes going back almost 2,000 years.
Dr. Donnelly took core samples going down 30 feet into the sediment at the bottom in the middle of Salt Pond, which is quite a distance from the shore of Vineyard Sound. Major storms, Hurricane Bob was one of them, made themselves evident by a notable layer of sand driven deep into the pond by wind-driven waves.
Interestingly, the major hurricanes of the mid-century were not in evidence. Dr. Donnelly and his colleagues hypothesize that those storms made landfall too far to the west to create the sand deposits.
But others did, and there were many of them. The scientists found evidence of 23 powerful hurricanes between 150 AD and 1150. They found that the years between 1400 and 1675 were also very active. Those periods coincide with periods of warm tropical oceans and the later group with a period when the oceans were warm along the Eastern Seaboard.
Scientists agree that warmer oceans will lead to more powerful storms. Dr. Donnelly’s Salt Pond samples shows this to be the case.
What is more, Dr. Donnelly points out, there were periods of intense storms before human-induced climate change. If the Cape once experienced storms unprecedented in recent history, what might we expect now that the climate is growing warmer?