World - Study Reconstructs Ancient Storms to Help Predict Changes in Tropical Cyclone Hotspot
Intense tropical cyclones are expected to become more frequent as climate change increases temperatures in the Pacific Ocean.
But not every area will experience storms of the same magnitude. New research from the Woods Hole Oceanographic Institution (WHOI) published in Nature Geoscience reveals that tropical cyclones were actually more frequent in the southern Marshall Islands during the Little Ice Age, when temperatures in the Northern Hemisphere were cooler than they are today.
This means that changes in atmospheric circulation, driven by differential ocean warming, heavily influence the location and intensity of tropical cyclones.
In the first study of its kind so close to the equator, lead author James Bramante reconstructed 3,000 years of storm history on Jaluit Atoll in the southern Marshall Islands. This region is the birthplace of tropical cyclones in the western North Pacific--the world's most active tropical cyclone zone. Using differences in sediment size as evidence of extreme weather events, Bramante found that tropical cyclones occurred in the region roughly once a century, but increased to a maximum of four per century from 1350 to 1700 CE, a period known as the Little Ice Age.
Bramante, a recent graduate of the MIT-WHOI Joint Program in Oceanography/Applied Ocean Science and Engineering, says this finding sheds light on how climate change affects where cyclones are able to form.