ASTER SWIR is deteriorating quickly

[Jeff Kargel]

Dear GLIMS colleagues,

There has been a lot of activity in the past year regarding managing and trying to maintain SWIR temperatures for ASTER, which is necessary to collect high-quality data.  The effort is increasingly a difficult battle, as Michael Abrams's note below indicates.  The most recent effort resulted in several months' of continued high-quality data collection, but most recently we are back to a condition where VNIR and TIR (I hope also SWIR band 4) is useful but other SWIR bands do not provide usable data. The situation after the next round of maintenence might permit resumption of SWIR data collection for the better fraction of a year(probably with several of these thermal anomaly cycles, as there have been already), if we're lucky, but it is anticipated that SWIR will deteriorate until it is permanently useless.  Hopefully we have not crossed that line yet.  

Just a warning that the days of SWIR are numbered in the low hundreds, if that.   VNIR and so far TIR are not affected, and ASTER band 4 is the least vulnerable of the SWIR bands.  Hopefully the recent notes about future availability of free Landsat data (globally) and availability of free Arctic SPOT data may brighten your day.

--Jeff Kargel

-----Forwarded Message-----
>From: Michael Abrams <Michael.J.Abrams at jpl.nasa.gov>
>Sent: Apr 25, 2008 1:37 PM
>To: asterteam at jpl.nasa.gov
>Subject: swir
>
>the swir temperature took off yesterday, and is at 92 now. so data are 
>very poor. we will do another recycle May 7. Until then, expect swir 
>data to be worthless
>
>-- 
>Michael Abrams
>ASTER Science Team Leader
>NASA/Jet Propulsion Laboratory
>Mail Stop 183-501
>4800 Oak Grove Dr.
>Pasadena, CA 91109
>818-354-0937  FAX: 818-354-5148
>michael.j.abrams at jpl.nasa.gov
>
>