14 April 2017

Supercomputer Recreation of an Oklahoma Tornado

Posted by Dan Satterfield

A big hat tip to Tim Schmit at the Uni. of Wisconsin SSEC for this:

Look at the animation below of a supercell with a large tornado that was re-created using a supercomputer.

From the video tag on YouTube:
Using supercomputers, a team led by UW-Madison CIMSS researcher Leigh Orf, successfully recreated a monstrous supercell that produced several tornadoes in 2011, one of which registered as an EF-5 and touched down near El Reno, Oklahoma. 

Sequence 1) The start of the EF5 tornado, a process known as tornado genesis, shown in the vorticity (spin) field. From left to right, different panel views of the forming tornado looking towards the southeast, south, southwest, and northwest.

Sequence 2) During the process leading up to tornado genesis, a “parade of vortices” moves along the forward flank of the storm (from right to left) towards the location where the tornado will form, and evidence of these vortices can be seen as tiny descending funnels in the cloud field at the base of the cloud. Horizontal slices indicating vertical motion and reflectivity (what radar would see) at 1km above the ground are added to the sequence, as well as surface buoyancy, delineating the storm’s cold pool. We then jump ahead forty minutes where the tornado is producing winds in excess of 300 miles per hour and exhibiting a multiple vortex structure. Finally, the tornado becomes rain-wrapped towards the end of its life.

How was this done? Watch the lecture below: