Cooperative Institute for Meteorological
Satellite Studies (CIMSS)
Real-time GOES winds.
Specialized GOES wind products based on a feature tracking technique
were produced by CIMSS as part of the CALJET experiment in 1998. A
unique component of this data set is the availability of
super-rapid-scan (1-min sampling) GOES images. These data were used
to assess the impact of shortening the time between images used in
feature tracking. Standard approaches used 30-min between samples,
but tests in tropical storms had suggested more frequent sampling
could improve areal coverage in regions where cloud features had a
shorter lifetime than 30 min. The figures shown here represent the
results of this test using a 5-min lag between images for both IR and
visible channels. These are compared to results using 30 min lag, and
confirm that the areal data coverage increases significantly. Using
statistical internal consistency checks it was determined that the
optimal time lag was about 5-min. Wind vectors calculated using
shorter lags had higher internal variance that resulted from the
increased influence of satellite pointing uncertainty as the distance
between features decreased, i.e., with shorter time lags. Based on
these results, a new GOES scan pattern is being developed that should
provide a set of 3 consecutive 5-minute interval images, once every
hour around the clock during PACJET over the domain shown here.
In addition to the GOES wind products, GOES sounder moisture products
(total precipitable water vapor, and cloud-top pressure) will be
available at 3-hourly intervals.
UW-CIMSS Automated Tracking Algorithm
GOES-9 VIS Cloud Drift Winds
Using Routinely Available Data (30 Min.)
Full Sized Image (312k)
![](img/goes/6FEB-RT-VI.2.gif)
UW-CIMSS Automated Tracking Algorithm
GOES-9 VIS Cloud Drift Winds
Using Super Rapid Scan Data (5 Min.)
Full Sized Image
![](img/goes/6FEB-SRSO-VI.2.gif)
UW-CIMSS Automated Tracking Algorithm
GOES-9 IR Cloud Drift Winds
Using Routinely Available Data (30 Min.)
Full Sized Image
![](img/goes/6FEB-RT-IR.2.gif)
UW-CIMSS Automated Tracking Algorithm
GOES-9 IR Cloud Drift Winds
Using Super Rapid Scan Data (5 Min.)
Full Sized Image
![](img/goes/6FEB-SRSO-IR.2.gif)
Cloud Top Pressure
![](img/goes/98023-21.ctp.gif)
Total Precipitable Water Vapor
![](img/goes/98024-00.pw.gif)
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