On The Radio – September 2017 record-setting month for hurricanes


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Hurricane Maria churning over the Atlantic Ocean. (NASA)
Jenna Ladd | October 23, 2017

This week’s On The Radio segment discusses the unprecedented severity of hurricane activity in the Atlantic ocean this September. 

Transcript: September 2017 was a record-setting month for hurricane activity in the Atlantic Ocean.

This is the Iowa Environmental Focus.

It is common for September to be the most active month for hurricanes because low pressure systems often move across the Atlantic and meet the tropical waters of the Caribbean during that month, but September 2017 was a cut above the rest.

The beginning of September brought Hurricane Harvey, a category four storm which caused unprecedented damage to, Houston, the U.S.’s fourth largest city. Five additional hurricanes left paths of destruction across the Caribbean and Florida during September, with Irma and Maria both reaching category five status.

Last month, the overall intensity and duration of storms, known as “accumulated cyclone energy,” was 175 units, significantly higher than September 2014’s record of 155 units. While climate change has not been found to cause hurricanes, there is evidence to say that rising sea temperatures make them stronger.

For more information, visit Iowa-environmental-focus-dot-org. From the UI Center for Global and Regional Environmental Research, I’m Betsy Stone.

On The Radio – Storms like Harvey more likely due to changing climate


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Texas National Guard members rescue residents in a heavily flooded area of Houston. (Texas Military Department/flickr)
Jenna Ladd| September 11, 2017

This week’s On The Radio segment discusses how climate change is making storms like Harvey more likely.

Transcript: Over 51 inches of rain fell in the Houston area last month during Hurricane Harvey, setting a record for the continental U.S., and scientists say a changing climate added to the deluge.

This is the Iowa Environmental Focus.

The Clausius-Clapeyron equation, a law of thermodynamics, says that the warmer a body of air is, the more moisture it can hold. Sea surface temperatures near where Harvey picked up its strength were about 1 degree Celsius higher than average, making the air above it warmer too. In this case, the atmosphere surrounding Hurricane Harvey was able to hold roughly three to five percent more moisture than usual.

In addition, sea levels have risen by about six inches in the last few decades due to global warming. Even minimal sea level rise can lead to a large increase in damages to structures on land during a flood.

While climate change did not cause Hurricane Harvey directly, scientists say it will likely make category four storms like it more frequent in the future.

For more information, visit iowa-environmental-focus-dot-org.

From the UI Center for Global and Regional Environmental Research, I’m Betsy Stone.