Ice breakup in the northern portion of Green Bay

March 15th, 2011 |
MODIS true color Red/Green/Blue (RGB) images

MODIS true color Red/Green/Blue (RGB) images

 

A comparison of 250-meter resolution MODIS true color Red/Green/Blue (RGB) images from the SSEC MODIS Today site (above) shows the breakup of ice in the northern portion of Green Bay, Wisconsin. It can be seen that there is a significant amount of ice motion (due to southwesterly winds) in the time between the 16:52 UTC Terra MODIS image and the 18:35 UTC Aqua MODIS image — and other smaller ice floes can also be seen moving in portions of northern Lake Michigan and southern Lake Superior. Also note that the southwest-to-northeast oriented long-track tornado damage path from the 07 June 2007 severe convection event could still be clearly identified about 100 km to the west of the ice-covered portion of Green Bay.

An animation of McIDAS images of 1-km resolution GOES-13 0.63 µm visible channel data (below; click image to play animation) does show the movement of the ice in the northern portion of Green Bay during the day — but even at an image interval of 15 minutes, errors in the Image Navigation and Registration (INR) tend to produce a bit of “wobble” which makes tracking the ice motion more difficult.

GOES-13 0.63 µm visible channel images (click image to play animation)

GOES-13 0.63 µm visible channel images (click image to play animation)

With the next-generation Advanced Baseline Imager (ABI) on the future GOES-R satellite, the spatial resolution of the visible channel will be improved to 500 meters — and the nominal temporal resolution of images over the continental US will be every 5 minutes (although 30-second image intervals will be available for special weather situations). CIMSS participation in GOES-R Proving Ground activities includes the creation of model-simulated ABI visible images, as well as model simulations of 9 other ABI InfraRed (IR) band images.

Subtropical Storm “Ariani” off the coast of Brazil

March 15th, 2011 |

 

GOES-12 0.65 µm visible images (click image to play animation)

GOES-12 0.65 µm visible images (click image to play animation)

 

 

Subtropical Storm “Ariani” developed off the southeast coast of Brazil on 15 March 2011. GOES-12 0.65 µm visible channel images (above; click image to play animation) displayed a number of overshooting tops within the large cloud shield of the disturbance. Some hints of a cyclonic (clockwise in the Southern Hemisphere) circulation could be seen both within the southern flank of the cloud shield, and also just to the southwest of the cloud shield over the open water.

GOES-13 10.7 µm IR images from the CIMSS Tropical Cyclones site (below; click image to play animation) showed a broad area of old cloud tops associated with this feature.

 

GOES-13 10.7 µm IR images (click image to play animation)

GOES-13 10.7 µm IR images (click image to play animation)

 

A GOES-13  IR/Water Vapor difference product (below; click image to play animation) did indicate that there was a large area of overshooting tops (red to violet color enhanced areas). For more information on this product and its application to tropical cyclone intensity analysis, see Olander and Velden, 2009.

 

GOES-13 IR/Water Vapor difference product (click image to play animation)

GOES-13 IR/Water Vapor difference product (click image to play animation)