Next-Gen Weather Satellites to Improve Tornado Warnings   
       
   Feb 29, 2012: When you read the following paragraph, consider the following:   
   Tornado season hasn't even started yet.   
       
   On Jan. 22 and 23, 2012, more than 37 tornadoes struck the southern USA. Ten   
   of them tore across the Lower Mississippi Valley into Alabama. Worst hit were   
   St. Clair and Jefferson County, Ala., where 2 people were killed, about 100   
   others injured, and at least $30 million in damage was done. It was a chilling   
   reminder of the April 2011 onslaught of deadly tornadoes that took a   
   staggering toll across southern and Midwestern states.1   
       
       
   In advance of a tornado, storm clouds approach Huntsville, AL, in April 2011.   
   More: A Story from the Tornado ZoneIn southern parts of the USA, tornado   
   season tends to peak in springtime. Yet January 2012 produced 73 winter   
   tornadoes -- third most of any January in recorded history. Most of them   
   struck southern states. And since over a quarter of the incredible 1,688   
   twisters confirmed across the US in 2011 occurred in the four-state region of   
   Alabama, Georgia, Mississippi and Tennessee, residents there are becoming ever   
   more wary of darkening skies.   
       
   "Even with our advances in science and communications, we can still be   
   surprised by the deadliest storms," says NOAA scientist Steve Goodman. "But   
   NOAA is working with NASA and university researchers to give more lead time in   
   tornado warnings."   
       
   Southern tornadoes are especially insidious and challenging to track. The   
   hilly, forested terrain in southern states makes an approaching twister harder   
   to spot than in the flat Midwest. In the south you might not see the first   
   evidence of an approaching tornado until it's almost in your back yard.     
       
   An Alabama resident describes the scene just before one of the April 2011   
   twisters struck near his home: "Suddenly, all the trees in my back yard   
   corkscrewed violently, in unison, toward the northwest." Moments later, the   
   storm was there.   
       
   Rain wrapped tornadoes are especially hard to see, as are night-time   
   tornadoes. And records indicate that southern tornadoes often strike at night.   
       
   To reduce the surprise, NOAA and NASA2 are developing the Geostationary   
   Operational Environmental Satellite-R, or "GOES-R series," with the first   
   expected to launch in late 2015. These next-generation weather satellites   
   bristle with state-of-the-art instruments for improved scouting of these   
   killer storms, even at night.   
       
   Tornadoes are, by their very nature, difficult to pin down. The Advanced   
   Baseline Imager (ABI) on GOES-R will improve meteorologists' ability to assess   
   conditions that spawn twisters. Compared to current GOES imagers, the ABI   
   provides twice the spatial resolution, three times as many channels of   
   information, and more than five times the update rate.   
       
   "ABI will give us a much clearer picture of the clouds - where and how tall   
   they are, how much and what kind of moisture they hold, and how they are   
   moving and intensifying," says NOAA research meteorologist Tim Schmit.   
       
   Most importantly, ABI can better detect the super-cold "overshooting tops"   
   that mean severe weather is imminent. "Overshooting tops portend huge energy   
   inside the cloud - it takes tremendous energy and upward velocity to poke   
   through the lid of the tropopause," explains Schmit.   
       
       
   A satellite image of a supercell thunderstorm with overshooting tops over   
   Kansas. Credit: NWS "During episodes of severe weather, ABI can show   
   conditions every 30 to 60 seconds. The system in use now only shows them every   
   7.5 minutes. And in normal mode, ABI will send readings over the continental   
   U.S. every 5 minutes as opposed to every 15-30 minutes."   
       
   Lightning is another key to tornadoes.   
       
   "Studies show that sudden changes in the total lightning correlate with [the   
   onset of] tornadoes," says Goodman.   
       
   Detecting lightning is a new specialty of GOES-R.   
       
   "GOES-R's Geostationary Lightning Mapper, or GLM, will see all the lightning:   
   cloud-to-ground, cloud-to-cloud, and inside each cloud. And since this is the   
   first time we'll have lightning detection from geostationary orbit, it means   
   GOES-R will constantly monitor and map the lightning across the western   
   hemisphere."   
       
   The GLM is expected to give 7 more minutes of lead time in tornado warnings.   
   Average lead time now is 13 minutes.   
       
   "With GOES-R you'll have upwards of 20 minutes to get to a safe haven."   
       
   That sure beats standing in your back yard, in the dark, waiting for the trees   
   to twist.   
       
       
   Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA   
       
   End Notes and Web Links   
   GOES-R Home Page   
       
   1Editor's Note:  Since this story was written, more than a dozen deadly   
   twisters (including one rated EF4) tore across the US Midwest on Feb. 28-29   
   injuring as many as 200 people and claiming 12 lives.   
       
   2NASA has partnered with NOAA throughout the development of GOES and GOES-R.   
       
   "NASA is a think-tank and proving ground for us," says Goodman. "They develop   
   and test new instruments, help us build the ones we'll use in the field, and   
   train us to use them."   
       
   For example, ABI works similarly to NASA's MODIS research sensor, which rides   
   on the Terra and Aqua satellites. Forecasters are working with MODIS data now   
   to train for using ABI. Similarly, NASA's Lightning Imaging Sensor on NASA's   
   Tropical Rainfall Measuring Mission satellite provides heritage for the   
   Lighting Mapper on GOES-R. For more information on NASA and other proving   
   ground activity, see http://cimss.ssec.wisc.edu/goes_r/proving-ground.html and   
   http://goesrhwt.blogspot.com.   
       
       
   Regards,   
       
   Roger   
      
   --- D'Bridge 3.75   
    * Origin: NCS BBS (1:3828/7)