NASA's Physical Oceanography Distributed Active Archive Center (PODAAC)
generates the Multiscale Ultrahigh Resolution sea surface temperature (SST)
product (version 4.1) that
combines data from all current microwave and infrared polar-orbiting and
geostationary satellites, including U.S. satellites and those of international
partners such as Japan and Europe.
The satellite instruments vary on a daily basis depending on
availability, but may include the following, among others:
- Advanced Microwave Scanning Radiometer-2 (AMSR-2) on Japan's GCOM-W1
- Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra and
- WindSat on the U.S. Navy's Coriolis satellite
- Advanced Very High Resolution Radiometer (AVHRR) on NOAA's POES
satellites and Europe's MetOp satellites
Nighttime skin and subskin SST observations from the available satellite
instruments are blended (analyzed) using an optimal interpolation approach,
called multi-resolution variational analysis (MRVA). The analysis technique
includes in-situ SST observations from the
NOAA iQuam project. As with data assimilation approaches, the in-situ
SST observations are used in a bias correction to "nudge" the satellite SST's
in the direction of the in-situ SST's for a more accurate analysis product.
The number of included satellite instruments, and the analysis technique,
allows for a daily, cloud-free, global product on a 0.01 degree grid
(approximately 1 km).
The multi-resolution variational analysis method is based on wavelet
decomposition. Its multi-scale design allows interpolation of the satellite
pixel data at an optimal resolution for each data set, which is particularly
useful for combining data sets from sensors with drastically different
Near real-time SST data are generated by PODAAC with a 2-day delay, and
retrospective science-quality SST data are generated with a 4-day delay.
NOAA CoastWatch East Coast Node obtains both the near real-time SST
and retrospective science-quality SST from PODAAC. East Coast Node
replaces the near real-time SST data files with the science-quality SST data
files when they become available. Further, East Coast Node subsets the global
data for the U.S. coasts. Currently, only U.S. east coast data files
are made available through East Coast Node. In addition to daily files,
monthly and annual mean composite files are available. East Coast Node
distributes the entire time series of MUR SST data, from June 2002 to the
Figure: PODAAC MUR SST for July 30, 2015
Compare with July 30, 2015 image of NOAA Geo-Polar
Blended SST and AVHRR SST Daily Composite
The Multiscale Ultrahigh Resolution SST project is funded by the
NASA MEaSUREs Program. More information may be found at the NASA Jet
Propulsion Laboratory MUR project page.
Chin, T.M., J. Vazquez, and E. Armstrong. 2013.
Algorithm Theorectical Basis Document: A multi-scale, high-resolution analysis
of global sea surface temperature, Version 1.3. NASA Jet Propulsion
Laboratory, Physical Oceanography Distributed Active Archive Center.