MTSTAT and CloudSat imagery of Typhoon Dolphin. Credits: Natalie D. Tourville/Colorado State University
The National Oceanic and Atmospheric Administration and the National Hurricane Center (NHC) use a variety of tools to predict these storms’ paths. These scientists need a wealth of data to accurately forecast hurricanes. NASA satellites, computer modeling, instruments, aircraft and field missions contribute to this mix of information to give scientists a better understanding of these storms.
This visible image of Hurricane Katrina was taken on August 29 at 05:16 UTC (1:16 a.m. EDT) by the MODIS instrument that flies aboard NASA’s Aqua satellite as it approached landfall in Louisiana. Credits: NASA Goddard MODIS Rapid Response Team
“Before we had satellites and aircraft, hurricanes would destroy entire cities, like the Labor Day Hurricane in Key West back in 1935,” said Gail Skofronick-Jackson. Hurricanes in the Atlantic Ocean can form when sub-Saharan thunderstorms travel westward with areas of lower pressure. These troughs are known as African Easterly Waves. Warm, moist air rises within the storm clouds, drawing air into the thunderstorms >> increases rotation of the air within the storm cloud. Moving across the warm Atlantic, this cycle repeats on a daily basis, and, with a favorable environment, potentially accelerates to create a monstrous vortex powered by oceanic heat.
NASA uses an arsenal of instruments to learn more about how these storms progress as they form. These devices orbit Earth on a fleet of spacecraft, including Aqua,Terra, the Global Precipitation Measurement core observatory, NASA-NOAA’s Suomi NPP satellite, Calipso, Jason-2 and CloudSat. “We can see the progression of a storm from one day to the next using the Terra and Aqua satellites—a morning and afternoon view of every storm system, every day.”
>>These instruments analyze different aspects of these storms, such as rainfall rates, surface wind speed, cloud heights, ocean heat and environmental temperature and humidity. Observing these factors helps identify the potential for storm formation or intensification + predict where, when and how hard hurricanes will strike land.
This 3-D view of the area northeast of Typhoon Dolphin’s eye on May 16 created by data from NASA/JAXA’s GPM core satellite shows heaviest rain over the open waters of the Pacific Ocean at a rate of over 65 mm (2.6 inches) per hour. Credits: NASA/SSAI/JAXA, Hal Pierce
NASA’s RapidScat instrument that flies aboard the ISS measures surface winds over the ocean and is used to gather data on tropical cyclones. This can show where in a hurricane the strongest winds occur. RapidScat continues a long satellite record of these observations that began with NASA’s QuikScat satellite. Scientists must completely understand a hurricane to predict its trajectory and strength. “We heavily rely on the passive microwave imagers from satellites to see what is happening in the core of the storm.”… Skofronick-Jackson said. “We learn about the amount of liquid water and falling snow in the cloud. Then we know how much water may fall out over land and cause floods.” With satellite data informing computer models, we can predict the storms’ paths, to the point where regions only need to evacuate half as much coastline as before.
>>NASA’s Global Modeling and Assimilation Office, or GMAO works to improve understanding of hurricanes and assess models and procedures for quality. GMAO helps to identify information that was missing and determines what services could be added to help future investigation and prediction of hurricane systems.
On July 14, RapidScat saw the sustained winds surrounding Claudette’s center of circulation were no stronger than 21 meters per second with the exception of stronger winds in the southwestern quadrant. Credits: NASA JPL/Doug Tyler
>>NASA also conducts field missions to study hurricanes via radiometers that read moisture levels; lidars that measure aerosols, moisture, and winds; dropsonde systems to measure high-resolution profiles of temperature, pressure, moisture, and winds; to Doppler radar systems to map the 3-D precipitation and winds within storms. These instruments monitor the structure and environment of hurricanes and tropical storms as they evolve.
In 2016, NASA is launching the Cyclone Global Navigation Satellite System, with 8 small satellites. CYGNSS will probe the inner core of hurricanes to improve hurricane intensity forecasts. http://www.nasa.gov/feature/goddard/how-does-nasa-study-hurricanes
Recent Comments