aqua satellite

The Aqua satellite carries a suite of sensors specially designed for observing all parts of Earth’s water cycle, including water on land, in the oceans, and in the atmosphere.

Reto Stöckli/NASA

Predicting Hurricane Intensity

If you live in a coastal region in which you're vulnerable to hurricanes, there are two crucial pieces of information that you want from weather forecasters. The first is what the hurricane's path will be, so that you know whether or not it's going to hit the place where you live. The second is how powerful the storm is going to be.

Since the early 1990s, meteorologists have significantly improved their ability to predict where storms developing in the ocean are headed. But unfortunately, the ability to predict the intensity of hurricanes hasn't improved anywhere near as much. The reason is that hurricanes' power is influenced by a complex array of factors, both inside the storm system and outside it, from the ocean's heat content to the relative humidity of surrounding environments. Making sense of all that from the ground has been a pretty daunting job [source: NASA].

But that's where NASA comes in. Its orbital satellites can see the big picture and gather enormous amounts of data about hurricanes from above as they develop. By matching up that data to how powerful the storms become, they hope to figure out which factors are the most reliable indicators of hurricane ]intensity, and how to predict the pace at which it develops.

Already, researchers from NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the University of Hawaii at Manoa have made one potentially important breakthrough. They've analyzed relative humidity data from the Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua space satellite for nearly 200 North Atlantic hurricanes between 2002 and 2010, and compared that to already available data on the maximum winds that those hurricanes produced. The researchers found that hurricanes that rapidly intensified tended to develop when their surrounding environment was more humid compared to the environments that produced weaker storms [source: NASA].

In 2014, NASA is planning to launch a new array of satellites that may give weather forecasters even more help in predicting hurricane intensity. The Cyclone Global Navigation Satellite System (CYGNSS), developed by engineers at the University of Michigan, will put a constellation of eight small satellites into a low-Earth orbit. The satellites' sensors will measure various properties in the ocean and the atmosphere, with the aim of coming up with a more precise model for how tropical cyclones form and how they strengthen [source: Moore].