GLM and Spatial Extent

One of the key advantages of the Geostationary Lightning Mapper (GLM) is the ability to observe the spatial extent of lightning.  The example here shows a 1 minute accumulation of the GLM event density over Louisianna and the Gulf of Mexico.  As an aside, a GLM event is any light detected by the GLM in a 2 ms time frame.  The GLM event density is compared with the corresponding radar reflectivity and the corresponding National Lightning Detection Network (NLDN) cloud-to-ground flash density, also at 8 km.  Unlike the GLM, the NLDN identifies the location that a flash goes to ground.  (For this example, the data were accumulated into an 8 km grid that masks this NLDN capability.)  The GLM in this example shows that the total lightning is extending well beyond the locations where flashes are coming to ground into the stratiform region.  Additionally, in the southwestern portion of this example, the GLM is showing intra-cloud lightning over the Gulf of Mexico where there are no cloud-to-ground observations.

glm_events_and_nldn

GLM 8 km, 1 minute event density accumulation (left) with the corresponding radar reflectivity and 8 km, 1 minute NLDN cloud-to-ground density (right).

NOTE:  NOAA’s GOES-16 satellite has not been declared operational and its data are preliminary and undergoing testing. Users receiving these data through any dissemination means  (including, but not limited to, PDA and GRB) assume all risk related to their use of GOES-16 data and NOAA disclaims any and all warranties, whether express or implied, including (without limitation) any implied warranties of merchantability or fitness for a particular purpose.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s