QuickSCAT Caveat!

[wxman57]

Just a reminder to everyone here about those QuickSCAT images. Be very careful to read the actual image time to the lower right of the image - NOT the time atop the web page. For example:

http://manati.wwb.noaa.gov/storm_at_ima ... 7_16ds.png

Note the time atop the web page now says updated 7:42 GMT. But look at the time to the lower right of the image in purple - "20:17". The image is 12 hours old.

It's even worse for Juan, the web page says last updated 7:42 GMT, but the image time is 9:32 GMT - over 24 hours old (unless the image just updated but the web page didn't!

http://manati.wwb.noaa.gov/storm_at_ima ... 7_15as.png

So beware of those images, as they can be as much as 24 hours older than the "update time" atop the web page.

[Aquawind]

Good Point..I learned that lesson earlier this year from MW. It's still kind of confusing when they list a couple times at the bottom. Is it always the lower Right time listed?

[wxman57]

Good Point..I learned that lesson earlier this year from MW. It's still kind of confusing when they list a couple times at the bottom. Is it always the lower Right time listed?

Yep, ignore the time up top, look at the time on the image, which is to the lower right of the image. The satellite orbits the Earth every 90 minutes, while the earth rotates beneath the orbital path. This way, it can "shoot" the entire planet in 24 hours or so. Of course this means that one location may not fall under the satellite's path for up to 24 hours, so QuickSCAT images can be quite old.

[cycloneye]

57 a question to you what is the term eclipse in the images that I hear a lot?

[wxman57]

Here's a good image showing QuickSCAT imagery may be VERY old:

http://manati.wwb.noaa.gov/storm_at_ima ... 1_90ds.png

Not the page says it was updated at 21:42Z (today), but the image time at the bottom right (in purple) says 23:37Z (yesterday). This descending-pass quickscat is almost 24hrs old.

[WeatherEmperor]

What does QuickSCAT mean?

[wxman57]

Read all about it here:

http://podaac.jpl.nasa.gov/quikscat/

In a nutshell, it involves using satellite to estimate near-surface wind speed and direction. This allows for the identification of developing low-level circulation centers in parts of the ocean void of any other measuring equipment.