Polder-1

POLDER-1 is the first instrument of the CNES POLDER series. It was the result of the first Franco-Japanese space cooperation and was embarked on the ADEOS satellite of NASDA (now JAXA).

Designed and developed by CNES, in close collaboration with the LOA atmospheric optics laboratory in Lille, the POLDER instrument is mainly dedicated to the study of the clouds and aerosols properties, but it also provides valuable information on the directionality of terrestrial reflectances and on the ocean colour. It has been the first space instrument to provide global and systematic spectral, directional and polarization measurements of radiation reflected from the Earth and atmosphere.

ADEOS (Advanced Earth Observing Satellite) / Midori

ADEOS is the first Japanese satellite mission with international cooperation. In Japan, the ADEOS satellite is also referred to as `Midori’, meaning `green’. The overall objective of the mission is dedicated to Earth environmental research: integrated observation of geophysical parameters, global observation of land, ocean and atmospheric processes.

It was launched on August 17, 1996. It operated nominally for 10 months but stopped functioning on June 30, 1997 after a loss of power due to structural damage in its solar array.

Main ADEOS orbit parameters:

• Sun-synchronous polar orbit
• Altitude: 797 km
• Inclination: 98.66°
• Local time crossing equator: 10:30 AM
• Repeat cycle: 41 days (subcycle 4 days)

Sensors on-board ADEOS

• OCTS (Ocean Color Temperature Scanner), a mechanical scanning (whiskbroom) radiometer, for ocean color and sea surface temperature measurements – NASDA instrument
• AVNIR (Advanced Visible and Near-Infrared Radiometer), an optoelectronic scanning radiometer using CCD detectors for land and coastal zone observations -. 5 spectral bands in VNIR range, 8-16 m spatial resolution, 80 km swath width – NASDA instrument
• NSCAT (NASA Scatterometer), a microwave radar instrument (fan-beam Doppler scatterometer) for measurement of surface wind speeds and directions over the global oceans – array of six 3-m long antennas, frequency 13.995 GHz, two swaths of 600 km width each, 50 km resolution – NASA/JPL instrument
• TOMS (Total Ozone Mapping Spectrometer), for observation of total ozone changes and observation of sulfur dioxide – 6 near UV spectral bands with 1 nm bandpass, 2795 km swath width, 50 km IFOV at nadir – NASA/GSFC instrument
• POLDER – CNES instrument
• IMG (Interferometric Monitor for Greenhouse Gases), a Fourier transform infrared spectrometer for mapping greenhouse gases on a global scale – spectral range 3.3 – 14.0 µm, 0.1 cm^-1 resolution, 8 km spatial resolution, 20 km swath width- MITI instrument
• ILAS (Improved Limb Atmospheric Spectrometer), visible and IR range spectrometer for measurement of atmospheric trace gases and the pressure and temperature profiles by the solar occultation technique – JEA (Japan Environment Agency) instrument
• RIS (Retroreflector In Space), a large aperture single element corner-cube reflector for laser long-path absorption measurements of atmospheric trace species – wavelength range: 0.4 – 14 µm – JEA (Japan Environment Agency) instrument

POLDER instrument:

POLDER instrument is a large field of view imaging radiometer. It analyses the intensity and direction of light reflected by the Earth and its atmosphere, as well as its polarization. Such measurements reveal some interesting properties of clouds and aerosols, thereby telling us more about how they affect climate.

Products

Level-1 and Level-2 products are daylight orbit passes whereas Level-3 products are global scale, daily and monthly syntheses (averages and statistics).

The processing of Level 1 was carried out by the CNES. The products are archived and distributed by CNES.

The scientific processing of aerosol, clouds, radiation and water vapour products was done by the ICARE Data and Services Center of AERIS. The products are archived and distributed by ICARE.

The products available in the catalog cover the period from October 30, 1996 to June 29, 1997.

The complete archive of POLDER-1 data has been reprocessed at the end of 2007 with the enhanced algorithms developed in the framework of the PARASOL project.