Saturday, May 26, 2012

ASCAT Notes and References

We are working on updating our presentation of satellite wind measurements and their use for practical marine weather.  As we go though this we have compiled a long list of valuable references that we cannot include directly in our study materials, so we will list them here for interested readers. As time goes by, we will fill in sections of this article with comments and new links.



(1) We start with a schematic video from EUMETSAT the folks who developed the program.  There is no audio with it. It is a bit clunky, but shows the principle once loaded. You immediately see the main difference between ASCAT and the former QuikSCAT. ASCAT has a different type of scatterometer which cannot sample the ocean directly below it. Thus there is a "nadir gap" in the data swath. This makes it rather difficult to predict precisely when we will get the next useful pass, but we are working on ways to solve that. We already have ways that work to within 2 hr.

(2) Next a very nice ASCAT overview from Ross Van Til at Colorado State University.

(3) The place you get the data from the US Ocean Surface Winds Team.

(4) Another source of ASCAT winds in a sense more primary as they are the agency that analyzes the data for Eurometsat.  Royal Netherlands Meteorological Institute (KMNI).

(5) NOAA Coastwatch has very nice maps but takes some clicking around to them… i.e. Data Access/Select a Region (confirm it offers Surface Winds) then choose Surface Wind/ ASCAT/ Metop-2 (same as Metop-A)/date.  Then click that for a zoom. If it does not zoom, right click and say open in new tab/window. 

Note 1. Coastwatch is oceanography oriented, and oceanographers show wind arrows backwards! i.e. their arrows point to the direction the wind comes from.  if they show a SW wind, it is actually a NE wind.  the price we pay for beauty.


Note 2. Coastwatch tells you the approximate time of the pass, but not precisely, so (3) or (4) remain best practical sources.

(6) Main source of data if you have the right tech software to view this raw data (NASA JPL).

(7) How to overlay ASCAT winds (and wx maps) onto Google Earth.


More to follow...

So far the best reference we know for the practical application of satellite winds is our own book Modern Marine Weather. Which is also available as an inexpensive pdf ebook,

2 comments:

  1. Nice web site.

    A small note: It is EUMETSAT rather than
    Eurometsat (www.eumetsat.int)

    Thanks
    Hans Bonekamp(EUMETSAT)

    ReplyDelete
    Replies
    1. Thanks for the compliment and note. Name fixed. And thank you and your colleagues for such a fine research program.

      Delete