We at NOAA are taking this opportunity to consolidate and standardize the near-real time sea level analyses offered on-line to the public. As of August 2002, we are referring our users to the U.S. Navy for mesoscale and to CNES for "climate-scale" analyses. Both groups combine all available altimeter data into a uniform product. Links are provided below.

Mesoscale Sea Level Analyses (US Navy)

These analyses are based on the methods developed at the Naval Research Lab at the Stennis Space Center. They are reliable at scales up to several hundred km, but revert to a climatological seasonal signal for very large scales. They are produced daily, 1-2 days behind real time. General information about these and other near-real time data can be found at the site maintained by the US Navy for the Global Ocean Data Assimilation Experiment http://www.usgodae.fnmoc.navy.mil

The procedure to use the Navy altimeter analysis is:

1. Download daily altim file, ~5MB/day compressed: ftp://usgodae1.fnmoc.navy.mil/pub/outgoing/fnmoc/data/ocn/altim

2. Run ocn_obs program to dump binary altim file to ascii 1/sec height data.

ftp://usgodae1.fnmoc.navy.mil/pub/outgoing/fnmoc/data/ocn/docs

Climate-Scale Analyses (CNES/French Space Agency)

These analyses are reliable at for both mesoscale and basin-scale studies, and are updated on a weekly basis. Information about accessing the CNES data can be found at http://www.jason.oceanobs.com/html/donnees/welcome_uk.html