effects of Typhoon Kai-Tak, July 2000, seen through different instruments
The effects of Typhoon Kai-Tak.
Click for full view:
(top) wind vector (white arrows) superimposed on the color image of Ekman pumping velocity on July 8, 2002; (middle) sea surface temperature observed by NASA's Tropical Rain Measuring Mission Microwave Imager on July 9, 2000; and (bottom) a composite map of ocean color observed by NASA's SeaWifs satellite, July 12 - 15, 2000.
New research findings from NASA's Quick Scatterometer (QuikScat) satellite and its SeaWinds instrument have documented for the first time the significant effect typhoons have on the ocean and ocean life. The findings will be presented during a press conference highlighting recent research and findings from QuikScat at the fall meeting of the American Geophysical Union on Saturday, December 7, at 8 a.m. Pacific Time.

A team of researchers from NASA's Jet Propulsion Laboratory, Pasadena, Calif., and the National Center for Ocean Research, Taipei, Taiwan, used satellite data to document the thermal and biological responses created by typhoon Kai-Tak in the northern part of the South China Sea in early July 2000. The team analyzed data from QuikScat in conjunction with data from NASA's Tropical Rain Measuring Mission and its Sea Viewing Wide-Field-of-View Sensor (SeaWifs).

The typhoon's passing stirred up the sea, causing sea surface temperatures to drop drastically and increasing the level of ocean chlorophyll by 300 times within a few days. The resulting phytoplankton blooms were evident for up to a month after the typhoon had passed.

"Typhoons can take a devastating economic and human toll," said Dr. W. Timothy Liu, Quikscat project scientist at JPL. "Our research sheds new light on these violent storms, demonstrating how they can also nurture life, fertilizing the sea and creating a bounty of food for fish. The increased ocean productivity also affects Earth's carbon cycle and our climate."

In addition to the typhoon research, the press conference will look at the significant contributions QuikScat data is making to global weather forecasting and how scatterometer data is being applied in new ways.

SeaWinds measures wind speed and direction over Earth's oceans. Climatologists, meteorologists and oceanographers use these daily, detailed snapshots of ocean winds to understand and predict severe weather patterns and climate changes. NASA is scheduled to launch a new, identical SeaWinds instrument aboard Japan's Advanced Earth Observing Satellite II (Adeos 2) on December 14 to continue the long-term collection of this vital data.

Dr. Son V. Nghiem, also of JPL, will discuss a unique way of using QuikScat data to monitor large seasonal wetlands and floods. Even though the satellite instrument is designed for ocean winds, it can be used to monitor seasonal changes in wetlands, which can assist in predicting river discharge, and provide early detection of flooding in some circumstances.

Dr. Kyle McDonald of JPL will discuss how QuikScat data is used to monitor seasonal processes at northern latitudes. By observing processes such as freezing and thawing, scientists will gain a better insight into the carbon budget, the length of growing seasons and how the process affects water in the landscape. Results of recent freezes and thaws in Siberia and Alaska will also be discussed.

Dr. Bob Atlas of NASA's Goddard Space Flight Center, Greenbelt, Md., will discuss how QuikScat data has improved weather forecasts and assisted marine forecasters. They have improved forecasts on locations and intensities of storms at sea, resulting in reduced loss of life and property damage.

The press conference will be held in Room 112 of the Moscone Convention Center, 747 Howard Street, San Francisco, Calif.

The California Institute of Technology in Pasadena manages JPL for NASA.

News Media Contact

Contacts: JPL/Alan Buis (818) 354-0474
Goddard Space Flight Center, Greenbelt, Md./Rob Gutro (301) 286-4044
American Geophysical Union Press Room/(415) 905-1007