Professor: Warmer climate means deadlier hurricanes
April 22, 2008
Climate change affects hurricanes – the real question is how much.
Kerry Emanuel, professor of atmospheric science at the Massachusetts Institute of Technology, reiterated this argument, accompanied by numerous charts and graphs, to approximately 100 people Tuesday night in the Sun Room of the Memorial Union.
Emanuel worked with a group at MIT to create an accurate model to predict hurricane movement based on the tracks of past hurricanes. The model’s simulations correlate with the tracks of actual hurricanes, and both the actual data and the predictions showed an increase in the power of hurricanes over the last 20 years.
“Hurricane power has increased by 60 percent in the last 20 years globally,” Emanuel said.
With this new technology, the MIT group can figure out how large a hurricane will be in a given climate.
Emanuel went on to explain that sea surface temperatures, the rising of which are direct results of increased greenhouse gas emissions, correlate directly with an increase in hurricane power.
“It really makes sense,” Emanuel said. “Heat is energy, so with an increase in heat you have an increase in energy.”Water temperature and storm power in the Atlantic have risen and fallen in unison several times since records have been kept. Some argue this is evidence that hurricane power is cyclic and not affected by global warming, a claim Emanuel challenges.
One issue that has been discussed within the scientific community is how to count hurricanes.
“We used to use airplanes and fly directly into the storm, which was great for measuring the power of the storm,” Emanuel said. “Now we use satellites, which can give you an exact count, but you can’t tell how powerful a storm is from a satellite.”
In the last 50 years, the frequency of hurricanes has varied little, with about 100 hurricanes forming every year. Emanuel said some take this information to mean that hurricanes are not changing, but he thinks they are.
“Frequency doesn’t mean anything,” Emanuel said. “You have to look at how powerful these storms were.”
Emanuel argued that comparing relatively small storms that never reach land to storms the size of Katrina is much like grouping every earthquake together.
“These are often called natural catastrophes,” Emanuel said. “But really, they are man-made catastrophes.”
Emanuel said hurricane damage is a direct result of humans continually developing hurricane-prone areas such as Florida.
“We are marching like lemmings to the sea,” Emanuel said.