EN1_MDSI_MER_FRS_2P - Full Resolution Full Swath Geophysical Product for Ocean, Land and Atmosphere

The Medium Resolution Imaging Spectrometer (MERIS) is one of 10 sensors deployed in March of 2002 on board the polar-orbiting Envisat-1 environmental research satellite by the European Space Agency (ESA). The MERIS instrument is a moderate-resolution wide field-of-view push-broom imaging spectroradiometer capable of sensing in the 390 nm to 1040 nm spectral range. Being a programmable instrument, it had the unique capability of selectively adjusting the width and location of its 15 bands through ground command. The instrument has a 68.5-degree field of view and a swath width of 1150 meters, providing a global coverage every 3 days at 300 m resolution. The MERIS instrument was primarily designed for measuring ocean color, but its scope of objectives was broadened to serve atmospheric and terrestrial observations as well. Communication with the Envisat-1 satellite was lost suddenly on the 8th of April, 2012, just weeks after celebrating its 10th year in orbit. All attempts to re-establish contact were unsuccessful, and the end of the mission was declared on May 9th, 2012.

The 4th reprocessing cycle, in 2020, has produced both the full-resolution and reduced-resolution L1 and L2 MERIS products. EN1_MDSI_MER_FRS_2P is the short-name for the MERIS Level-2 full resolution, geophysical product for ocean, land, and atmosphere. This Level-2 product comes in a netCDF4 package that contains both instrument and science measurements, and a Manifest file that provides metadata information describing the product. Each Level-2 product contains 64 measurement files that break down thus: 13 files containing water-leaving reflectance, 13 files containing land surface reflectance and 13 files containing the TOA reflectance (for all bands except those dedicated to measuring atmospheric gas - M11 and M15), and several files containing additional measurements on ocean, land, and atmosphere parameters.