TALLAHASSEE, Fla. - Scientists are continually exploring different aspects of hurricanes to increase the understanding of how they behave. Recently, two NASA-funded scientists from Florida State University analyzed ozone levels surrounding hurricanes. Their work could lead to better methods of forecasting the paths of the deadly storms.
Ozone Around Hurricane Erin -- This image shows the distribution of total ozone in and around Hurricane Erin on 12 September, 2001. Erin is represented in the middle of the image by a red dot with two "arms." The ozone level within the center of the hurricane is high (depicted in green). Surrounding the hurricane are lower levels of total ozone (depicted in blue). Within the core of the hurricane there is a weak downward motion which brings down ozone rich air from the upper atmosphere into the core of hurricane and therefore increases the total ozone there, while upward lift of atmosphere is dominant surrounding the hurricane eyewall. Credit: Florida State University
In their study, FSU meteorologists Xiaolei Zou and Yonghui Wu found that variations of ozone levels from the surface of the ocean to the upper atmosphere are closely related to the formation, intensification and movement of a hurricane. In studying meteorological data from 12 such storms, Zou and Wu noticed that over an area of 100 miles, the area surrounding each hurricane typically had low levels of ozone from the surface to the top of the storm. Whenever the hurricane intensified, the ozone levels throughout the storm decreased even more.
In addition, when Zou and Wu examined hurricanes using the ozone data, the eye of the storms became very clear. Because forecasters always try to pinpoint the eye of the hurricane, this knowledge will help with locating a storm's exact position and possibly lead to better tracking.
The National Oceanic and Atmospheric Administration's National Hurricane Center (NHC) is the agency that issues hurricane forecasts. Of the 12 storms analyzed, the ozone data and the NHC official report differed on the mean distance between the estimated eye by less than 18 miles during the most intense stage of the storms. When Zou and Wu added the satellite-observed ozone levels around a hurricane into a computer forecast model, the model greatly improved the predicted track that the hurricane would take.
"This research highlights the benefits of Total Ozone Mapping Spectrometer (TOMS) data in hurricane track and intensity prediction, an important forecasting problem since hurricanes often strike regions of high population and property growth, resulting in large natural disasters," said Zou.
Another interesting finding from Zou and Wu's research is that ozone levels give a clue that a storm will develop before other methods do. The early spin of a tropical cyclone is weak and sometimes covered by clouds, and not easily detected by satellites that provide pictures of clouds. The ozone data gives scientists a "look beyond the clouds."
Ozone is all around the world and in the upper and lower atmosphere. Ozone in the upper atmosphere protects life on Earth from harmful ultraviolet rays from the sun, which can cause sunburn and skin cancer in humans. Ozone close to the surface is a pollutant; on hot, humid days with little wind, it creates a haze, such as that over big cities, that is harmful to breathe.
By using NASA's satellite Earth Probe/TOMS total ozone data, forecasters can identify ozone amounts that are closely related to the formation, intensification and movement of a hurricane. Zou and Wu also found a strong relationship between ozone, air pressure and spin within the hurricanes.
Zou said that the connections between ozone levels and hurricane behavior are a very important step in understanding the storms.
For more information and images about this research, please see:
###
http://www.nasa.gov/vision/earth/environment/ozone_drop.html.
For more stories about FSU, visit our news site at www.fsu.com
Information Provided by NASA's Earth-Sun Science News Team (www.nasa.gov)
Contact: Xiaolei Zou
zou@met.fsu.edu
850-644-6025
Rachel Christofel
rchristo@mailer.fsu.edu
Products & Services
