Featured Research

from universities, journals, and other organizations

Storm Killers: Earth Scan Lab Tracks Cold Water Upwellings In Gulf

Date:
September 30, 2009
Source:
Louisiana State University
Summary:
As researchers develop new ways to better understand and predict the nature of individual storms, a largely unstudied phenomenon has caught the attention of scientists. Cool water upwellings occurring within ocean cyclones following alongside and behind hurricanes are sometimes strong enough to reduce the strength of hurricanes as they cross paths.

Complex interactions between the ocean and overlying atmosphere cause hurricanes to form, and also have a tremendous amount of influence on the path, intensity and duration of a hurricane or tropical weather event. As researchers develop new ways to better understand and predict the nature of individual storms, a largely unstudied phenomenon has caught the attention of scientists at LSU’s Earth Scan Laboratory, or ESL. Cool water upwellings occurring within ocean cyclones following alongside and behind hurricanes are sometimes strong enough to reduce the strength of hurricanes as they cross paths.

“Ocean cyclones are areas of upwelling, meaning that cold water is not far from the surface as compared to the water surrounding it,” said Nan Walker, ESL director. “The Gulf of Mexico is full of ocean cyclones, or cold water eddies, many of which move rapidly around the margin of Gulf’s Loop Current, which is the main source of water for the Gulf Stream.”

While the upwelling is important to Gulf fisheries because it delivers nutrients into the surface waters, causing algal blooms and attracting marine life to the areas, oceanographers have recently begun to realize that these cyclones intensify currents near the surface and along the bottom of the ocean in areas of gas and oil exploration.

“Now,” Walker added, “our research has shown that ocean cyclones also provide temperatures cold enough to reduce the intensity of large Gulf of Mexico hurricanes.”

Walker’s research team has been looking into the upwelling phenomena since 2004, when they were able to use satellite data received at the ESL to view ocean temperatures soon after Hurricane Ivan’s Gulf crossing.

“Clear skies gave us a rare opportunity to really analyze the oceanic conditions surrounding the wake of Ivan,” said Walker. “We saw abnormally low temperatures in two large areas along the storm’s track, where minimum temperatures were well below those required to support a hurricane, about 80 degrees Fahrenheit.” This suggested to Walker that areas of extreme cooling could be providing immediate negative feedback to Gulf hurricanes, decreasing their intensity.

“In Ivan’s case, we found that its wind field increased the counter-clockwise spinning of the ocean cyclones in its path, catapulting cold water to the surface, which in turn reduced the oceanic ‘fuel’ needed for the hurricane to maintain its strength,” said Walker. She observed that Ivan’s intensity decreased as it moved toward the Mississippi/Alabama coast, despite the presence of a large warm eddy, a feature generally known for its potential to increase hurricane strength. Thus, the impact of the cold eddies overwhelmed that of the warm eddy.

“Cool wakes are most beneficial when the storm occurs later in the season because the Gulf doesn’t warm as rapidly in fall and may not have time to warm back up,” said Walker.

The research being conducted at ESL could eventually lead to novel new weather study techniques.

“Our research, in collaboration with Robert Leben at the University of Colorado, is providing an advanced monitoring system so that likely ocean impacts can be assessed in advance of the Gulf crossing,” said Walker. “However, it is important to remember that we don’t predict; we provide valuable information that serves as tools for those in the business of predicting, such as the National Hurricane Center.”

Of course, this is only one facet of the work done at LSU’s ESL. The lab has played a major role in mapping hurricane-related flooding, tracking oil spills and determining causes for the size and location of dead zones in the Gulf of Mexico, along with many other tasks employing satellite imagery.

ESL was founded more than 20 years ago, and employs undergraduate students, many of whom stay on with the lab throughout their entire college career. The lab’s Web site, http://www.esl.lsu.edu/home/, serves as a wealth of information for researchers, students and the general public. It includes real-time imagery of atmospheric, oceanic and coastal conditions, detailed records of recent and past hurricanes, as well as various types of ocean imagery and research summaries. ESL is part of LSU’s Coastal Studies Institute and the Department of Oceanography and Coastal Sciences in the university’s School of the Coast & Environment.


Story Source:

The above story is based on materials provided by Louisiana State University. Note: Materials may be edited for content and length.


Cite This Page:

Louisiana State University. "Storm Killers: Earth Scan Lab Tracks Cold Water Upwellings In Gulf." ScienceDaily. ScienceDaily, 30 September 2009. <www.sciencedaily.com/releases/2009/09/090928172359.htm>.
Louisiana State University. (2009, September 30). Storm Killers: Earth Scan Lab Tracks Cold Water Upwellings In Gulf. ScienceDaily. Retrieved September 1, 2014 from www.sciencedaily.com/releases/2009/09/090928172359.htm
Louisiana State University. "Storm Killers: Earth Scan Lab Tracks Cold Water Upwellings In Gulf." ScienceDaily. www.sciencedaily.com/releases/2009/09/090928172359.htm (accessed September 1, 2014).

Share This




More Earth & Climate News

Monday, September 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Iceland Lowers Aviation Alert on Volcano

Iceland Lowers Aviation Alert on Volcano

AFP (Sep. 1, 2014) — Iceland has lowered its aviation alert on its largest volcano after a fresh eruption on a nearby lava field prompted authorities to enforce a flight ban for several hours. Duration: 01:07 Video provided by AFP
Powered by NewsLook.com
Lightning Hurts 3 on NYC Beach

Lightning Hurts 3 on NYC Beach

AP (Sep. 1, 2014) — A lightning strike injured three people on a New York City beach on Sunday. The storms also delayed flights and interrupted play at the US Open tennis tournament. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Thailand Totters Towards Waste Crisis

Thailand Totters Towards Waste Crisis

AFP (Sep. 1, 2014) — Fears are mounting in Bangkok that poor planning and lax law enforcement are tipping Thailand towards a waste crisis. Duration: 01:21 Video provided by AFP
Powered by NewsLook.com
Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Melting Ice Shelves Drive Rapid Antarctic Sea Level Rise

Newsy (Sep. 1, 2014) — A study of almost 20 years' worth of satellite images shows Antarctic sea levels are on the rise as ice shelves continue to melt. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins