S'COOL: Comparing to Satellite Data

In order of timeliness:

Within hours: Comparing to MODIS

The Terra and Aqua spacecraft both carry an imaging instrument: the MODerate Resolution Imaging Spectroradiometer (MODIS). Quick-look images are posted for daytime orbits of MODIS on the MODIS Rapid Response website about two hours after the time they are taken.

Within a week: Comparing to FLASHFlux

FLASHFlux is a relatively new project which takes the complicated CERES algorithms, brings in preliminary versions of the other required data streams, applies a preliminary calibration to the CERES data, and produces cloud information within a week. The results show up in the S'COOL Database as soon as they are ready.

Within several months: Comparing to CERES

The goal of the CERES project is to produce climate-quality information. Thus, great care is taken in the calibration of the CERES instrument. In addition, the CERES team brings in a large number of other pieces of information, in order to get the best possible understanding of the Earth's Radiant Energy. This includes maps of surface vegetation types, the presence of snow and ice, information from weather models that tells us about the amount of water vapor and other things in the atmosphere, etc. Finally, CERES also uses data from the companion imager instrument (VIRS on TRMM or MODIS on Terra and Aqua) to do the cloud detection and identification. (Read about an analysis of cloud properties obtained without using imager data by a summer intern with the S'COOL Project.)

VIRS and MODIS are the responsibility of other teams of scientists, and they have to deal with the same issues of calibration, etc, that we deal with on CERES. The CERES team is the only science team involved with the Terra and Aqua spacecraft which produces a global product depending on measurements from more than one instrument.

Once the imager data are ready, we can finally compute cloud properties. This generally happens several months after the data are taken. This process is complete on TRMM, which stopped functioning in Spring 2000 (Read about an analysis of the satellite/ground matches from the TRMM time period.) Data processing is proceeding for Terra and Aqua. The CERES data also appear in the S'COOL Database as soon as they are ready.

Comparing to other satellites

In addition to these Terra and Aqua-related sources, weather satellite imagery for most of the Earth is placed on the web in near real-time. Check out this list of links to get a picture that you can compare to what your students saw from the surface. For those in the United States, this site provides real-time imagery and recent loops of geostationary data.

S'COOL What to Observe Report Form Glossary