African storms spawn Atlantic hurricanes
Courtesy of NOAA.
JB: This is Earth and Sky. Scientists have discovered that many of the Atlantic hurricanes that strike the U.S. and the Caribbean begin their lives as storms over West Africa.
DB: Chris Thorncroft is a meteorologist at the State University of New York at Albany.
Chris Thorncroft: One of the interesting science questions here is that for every six weather systems that leave the west African coast . . . approximately only one of them becomes a hurricane. So we talk about seedlings, these are the seedlings leaving Africa?what we’re weak at the moment is knowing which one is going to become a hurricane.
JB: Scientists can watch hurricanes form using satellites. But to really understand how they form – or sometimes don’t form – scientists need ground-based measurements too. Thorncroft is part of a team that’s doing just that. One theory they’ll test goes like this – when an African storm system develops where the air is dry and dusty, it has a harder time building up clouds, rain – and eventually, hurricanes.
DB: There’s a bonus to understanding why some African storms turn into hurricanes and others don’t. Thorncroft says that if you can improve forecasts of how much rain will fall – and hence, how dry West Africa will be – then you might be able to make better predictions about hurricanes that will later hit the U.S. and the Caribbean.
_JB: Special thanks today to NASA explore, discover, understand. We’re Block and Byrd for Earth and Sky.
Find out more about AMMA – the African Monsoon Multidisciplinary Analysis project.
Read about the U.S. component of AMMA.
Visit the U.S. National Hurricane Center to see the latest Atlantic hurricane season outlook.
Thorncroft studies weather using satellites. But the satellites need to be calibrated with real weather data on the ground. And that’s a problem in much of Africa right now – there just isn’t enough money from local governments to take many ground based weather measurements. So Thorncroft is conducting a three year project called AMMA – African Monsoon Multidisciplinary Analysis – that will simultaneously measure the weather over West Africa from various vantage points – the ground, airplanes, ships, weather balloons, radar towers – and of course, satellites. Then, in the future, scientists will know which satellites are most useful for monitoring Africa in this region and will be more confident in their measurements.
Our thanks to:
Chris Thorncroft
Associate Professor
Department of Earth and Atmospheric Sciences
State University of New York (SUNY), Albany
Albany, New York
Additional Teacher Resources
Science Daily: How hurricanes are born off the African coast
Scientists are using airplanes, sensors, radar, computer modeling programs and NASA satellites to better understand hurricanes. Some of the NASA satellites include Aqua, the Tropical Rainfall Measuring Mission (TRMM), and the recently launched Cloudsat/CALIPSO satellite. Edward Zipser of the University of Utah, Salt City, is the chief mission scientist. This article is an on-location report from Dr. Zipser during the NAMMA Hurricane field mission, the site also includes additional resources.
NASA Earth Observatory: NASA African Monsoon Multidisciplinary Analyses 2006
NAMMA-2006 provided new insight into the processes that govern hurricane growth and evolution. It is a component of African Monsoon Multidisciplinary Analysis (AMMA), an international project aimed at improving knowledge and understanding of the West African Monsoon and its variability. This site provides in depth analysis of the project as well as links to more information.
