Define MERIS.

MERIS, or the Medium Resolution Imaging Spectrometer, was an advanced optical instrument designed for Earth observation and remote sensing. It was part of the payload aboard the European Space Agency's (ESA) Environmental Satellite (Envisat), a large Earth observation satellite launched in 2002. MERIS played a key role in monitoring and studying various aspects of the Earth's surface and atmosphere, contributing valuable data for scientific research and environmental management.

Key Features of MERIS:

1. Spectral Coverage:

   • MERIS operated in the visible and near-infrared regions of the electromagnetic spectrum, covering wavelengths from 390 to 1040 nanometers. This broad spectral range allowed for the acquisition of information related to land cover, vegetation, coastal zones, and atmospheric properties.

2. Spectral Resolution:

   • With a total of 15 spectral bands, MERIS provided medium spectral resolution, allowing for detailed characterization of different Earth features. This capability made it suitable for a wide range of applications, including ocean color monitoring, land cover classification, and atmospheric studies.

3. Spatial Resolution:

   • MERIS offered a spatial resolution of 300 meters, providing moderate detail for land and ocean observations. This resolution struck a balance between fine detail and wide-area coverage.

4. Ocean Color Monitoring:

   • One of the primary objectives of MERIS was to monitor ocean color, capturing information about chlorophyll concentrations, suspended sediments, and water quality. This capability was crucial for understanding marine ecosystems, detecting algae blooms, and assessing coastal water conditions.

5. Land and Vegetation Monitoring:

   • MERIS contributed to land cover monitoring by capturing data related to vegetation health, land use changes, and surface properties. This information was valuable for applications such as agriculture, forestry, and environmental management.

6. Atmospheric Studies:

   • MERIS also played a role in atmospheric studies, providing data on aerosols, clouds, and other atmospheric constituents. This information was essential for understanding climate dynamics and air quality.

7. Global Coverage:

   • Operating in a sun-synchronous polar orbit aboard Envisat, MERIS provided global coverage, allowing for systematic observations of the Earth's surface and atmosphere over different regions and time periods.

Envisat, along with MERIS, significantly contributed to the understanding of Earth's environmental changes and provided a wealth of data for scientific research and policy-making. Unfortunately, the Envisat mission ended in 2012, concluding the operational phase of MERIS. Despite this, the data collected by MERIS continues to be valuable for ongoing scientific studies and environmental monitoring efforts.