13.
Western Boundary Currents and Storms
(Typhoons, Cyclones and Hurricanes)
Expedition Menu
1. Introduction
2. Tracking Drifters
3. Drifters Pacific
4. Drifters Atlantic
5. Drifters Indian
6. Velocity Pacific
7. Velocity Atlantic
8. Velocity Indian
9. Global Circulation
10. Counter Currents
11. Boundary Currents
12. Western Boundary
Currents
13. Typhoons & Hurricanes
14. Eastern Currents
Behold Cimaron
A Child of Ocean Circulation
The warm sea surface temperatures of western boundary currents, and overlying masses of warm air, provide the energy to generate the major ocean-borne storms, such as the typhoons in the western Pacific, as you see above, hurricanes on the west Atlantic and Gulf of Mexico (see the infamous Katriana below), and the cyclones near Australia and in the Indian Ocean.
Image Provided by NASA, Earth Observatory
"Like streamers of splattered paint, the tracks of nearly 150 years of tropical cyclones, hurricanes and typhoons weave across the globe in this map. The map is based on all storm tracks available from the National Hurricane Center and the Joint Typhoon Warning Center through September 2006. The accumulation of tracks reveals several details of hurricane climatology, such as where the most severe storms form and the large-scale atmospheric patterns that influence the track of hurricanes (and the clear association with the warm, tropical waters along the equator, which become the western boundary currents).Over time, the repeated passage of strong storms through the same regions creates solid swashes of color: bright red in the Western Pacific near the Philippines, where numerous Category 5 storms have traveled; orange and gold in the Caribbean and the Gulf of Mexico, where Category 3 and 4 storms often pass. The blues and light yellows reveal storms in a weaker state: near the equator, in their first stages of development; over land, as they run out of steam; in the mid-latitudes, where they encounter cooler waters.
To the west of South America, the Peru Current snakes northward along the coast of Chile, Peru, and Ecuador, bringing cool water from southern polar regions. A similar situation happens off western North America, where the California current brings cold water down from Alaska and Canada, resulting in few hurricanes. By the time the sea temperature warms off Mexico, hurricanes can form again. The cool currents keep waters from reaching hurricane-friendly temperatures. A similar cold current, the Benguela Current, flows up the western coast of South Africa, past Namibia and Angola, keeping those waters too cool for hurricanes as well.
--------modified from Historic Tropical Cyclone Tracks, NASA Earth Observatory
Last Updated
on
April 6, 2001
Send
to Don Reed
Department of Geology
San José State University
Given this relationship,
do the western boundary currents play a significant role in disasters
striking the southeastern United States, Japan, the Philippines, China,
southeast Asia and southern Mexico?