Featured Research

from universities, journals, and other organizations

NASA Study Finds 'Pre-Existing Condition' Fueled Killer Cyclone

Date:
March 11, 2009
Source:
NASA/Jet Propulsion Laboratory
Summary:
A "pre-existing condition" in the North Indian Ocean stoked the sudden intensification of last year's Tropical Cyclone Nargis just before its devastating landfall in Burma, according to a new NASA/university study. The cyclone became Burma's worst natural disaster ever and one of the deadliest cyclones of all time.

In early May 2008, Cyclone Nargis passed over Burma (Myanmar) after forming in the Bay of Bengal.
Credit: NASA image by Jeff Schmaltz, MODIS Rapid Response Team, Goddard Space Flight Center

A "pre-existing condition" in the North Indian Ocean stoked the sudden intensification of last year's Tropical Cyclone Nargis just before its devastating landfall in Burma, according to a new NASA/university study. The cyclone became Burma's worst natural disaster ever and one of the deadliest cyclones of all time.

Scientists at the National Taiwan University, Taipei; and NASA's Jet Propulsion Laboratory, Pasadena, Calif., used data from satellite altimeters, measurements of ocean depth and temperature and an ocean model to analyze the ocean conditions present at the time of the catastrophic storm. Nargis intensified from a relatively weak category 1 storm to a category 4 monster during its final 24 hours before making landfall on May 2, 2008.

Lead author I-I Lin of National Taiwan University and her team found the ocean conditions Nargis encountered created the perfect recipe for disaster. Cyclones thrive on warm layers of ocean water that are at least 26 degrees Celsius (79 degrees Fahrenheit). As they traverse the ocean, they typically draw deep, cold water up to the ocean surface, a process that limits their ability to strengthen, and even weakens them as they evolve. However, Nargis passed over a pre-existing warm ocean feature in the Bay of Bengal where upper ocean warm waters extended deeper than normal, from 73 to 101 meters (240 to 331 feet).

"This abnormally thick, warm water layer, which formed about a month earlier, kept deeper, colder waters from being drawn to the surface, increasing the energy available to fuel Nargis' growth by 300 percent," said Lin. "Combined with other atmospheric conditions conducive to strengthening, this warm ocean feature allowed Nargis to reach speeds of 115 knots [213 kilometers, or 132 miles, per hour] at landfall. Had Nargis not encountered this warm ocean feature, it would likely not have had sufficient energy to intensify rapidly."

Nargis' rapid intensification occurred predominantly over warm ocean regions where sea surface temperatures ranged between 30 and 30.2 degrees Celsius (about 86 degrees Fahrenheit) and sea surface heights ranged from 6 to 20 centimeters (2.4 to 7.9 inches) above normal. Between May 1 and 2, 2008, the storm intensified from category 1 to category 4. When Nargis briefly passed outside the warm ocean region on May 2, it weakened somewhat, only to strengthen once again as it returned to the warm ocean feature. Warm ocean features in the Gulf of Mexico contributed to the rapid intensification of hurricanes Katrina and Rita in 2005.

Lin said the research will contribute to improving our understanding of and ability to forecast catastrophic events like Nargis in the future, reducing loss of life and property. "Such a capability is particularly needed in developing countries, where less advanced cyclone monitoring and warning systems can leave people with little time to escape from disaster," she said.

The scientists compared the thermal structure of the upper ocean waters within the warm ocean feature during the storm with its thermal structure under normal climatological conditions. Study data came from the international Argo float program, NASA's Jason-1 satellite, the European Space Agency's Environmental Satellite, the U.S. Navy's GEOSAT Follow-On satellite and NOAA's Global Temperature and Salinity Profile Program data base. The satellite data were used to derive the upper ocean thermal structure for regions where no suitable direct measurements were available.

"This research demonstrates a significant potential benefit of using altimeter data for operational weather forecasting and tropical cyclone intensity predictions," said study co-author Tim Liu of JPL. "Current hurricane analyses include variations in ocean heat, which can be revealed by ocean altimeters. Satellites like NASA's Jason-1 and Ocean Surface Topography Mission/Jason-2 make important contributions to the operational monitoring and prediction of tropical cyclones, as have other NASA satellites."

Results of the study were published this month in Geophysical Research Letters.

For more information on Jason-1 and NASA's satellite altimetry programs, visit: http://sealevel.jpl.nasa.gov .


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "NASA Study Finds 'Pre-Existing Condition' Fueled Killer Cyclone." ScienceDaily. ScienceDaily, 11 March 2009. <www.sciencedaily.com/releases/2009/03/090302111153.htm>.
NASA/Jet Propulsion Laboratory. (2009, March 11). NASA Study Finds 'Pre-Existing Condition' Fueled Killer Cyclone. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2009/03/090302111153.htm
NASA/Jet Propulsion Laboratory. "NASA Study Finds 'Pre-Existing Condition' Fueled Killer Cyclone." ScienceDaily. www.sciencedaily.com/releases/2009/03/090302111153.htm (accessed April 17, 2014).

Share This



More Earth & Climate News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
How Mt. Everest Helped Scientists Research Diabetes

How Mt. Everest Helped Scientists Research Diabetes

Newsy (Apr. 15, 2014) British researchers were able to use Mount Everest's low altitudes to study insulin resistance. They hope to find ways to treat diabetes. Video provided by Newsy
Powered by NewsLook.com
The Walking, Talking Oil-Drigging Rig

The Walking, Talking Oil-Drigging Rig

Reuters - Business Video Online (Apr. 15, 2014) Pennsylvania-based Schramm is incorporating modern technology in its next generation oil-drigging rigs, making them smaller, safer and smarter. Ernest Scheyder reports. Video provided by Reuters
Powered by NewsLook.com
In Washington, a Push to Sterilize Stray Cats

In Washington, a Push to Sterilize Stray Cats

AFP (Apr. 14, 2014) To curb the growing numbers of feral cats in the US capital, the Washington Humane Society is encouraging residents to set traps and bring the animals to a sterilization clinic, after which they are released.. Duration: 02:29 Video provided by AFP
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