Monday, May 28, 2012

Overlay Auto-updating ASCAT Wind Data on Google Earth




We can overlay the graphic display of ASCAT data on Google Earth (GE) in such a way that it will be automatically updated with the latest satellite pass each time you open Google Earth. It is not completely automatic process, but it is more or less straight forward.  Below is a video that explains the process.  Note that this was a post from 2012, now updated in 2018, but essentially no changes to the process. This is not new info, but this new video may raise some interest in the process.




Once you have the kmz files created in GE and stored on your computer, you can then send them to a friend to run on their computer.  Below are a couple examples we made. These too can just be saved and used as you like.

The video shows that the descending pass kmz file can be made from the ascending file, by just changing the kmz file name and one letter in the link.

Florda waters ascending

Florida waters descending

We also have others for  Bermuda, Transpac, Tropical Atlantic, and Sydney-Hobart, Baja ascending, Baja descending.

This process can be pursued by adding weather maps, which can then be directly compared to the ASCAT data.  Here is an example for Florida waters to compare with the above FL ASCAT data. All are updated automatically.

Unified analysis map of Florida waters

Since ASCAT has two satellites (Metop A and Metop B), which follow the same orbits 47 minutes apart, there is another trick that can be done by georeferencing both in GE, side by side, you get effectively a much wider swath of data.  We miss squall activity that might have occurred between passes, but for ocean analysis it is a nice trick.  We do this in several of the above samples.

We have an extensive discussion of ASCAT data and its use in our new textbook Modern Marine Weather, 3rd ed.

Likewise we have other articles online about ASCAT.  An index to these is at www.starpath.com/ascat


1 comment:

David Burch said...

apologies. when we first posted these links we used the google docs option, but it turns out they force users to have an account... hence we have moved these to our own server, so you can download without that hassle.

we will remove this note in a week or so.