Measurements and Applications
GeoCarb Mission employs a 4-channel slit imaging spectrometer that measures reflected IR sunlight at wavelengths 1.61µm and 2.06µm for XCO2, and 2.32µm for XCH4 and XCO. The fourth channel, 0.76µm, measures O2 column concentration and SIF, and it also provides valuable information on aerosol and cloud contamination. The North/South (N/S) extent of the scan is fixed at a 4.4° field of view, which maps to 25° latitude or 2800 km at the Sub-Satellite Point (SSP). There are 1016 N/S samples with 4.1 km spatial resolution, spaced 2.7 km apart on center. The measurements are acquired in an East to West (E/W), 0.3825s step, and 4.08s stare (integration) mode, with 3 km sampling EW steps and 5.4 km resolution at SSP.
Full Name
Scanning Spectrometer (GeoCarb)
Status
No longer considered
Instrument Agencies
Maturity
Instrument Type
Atmospheric chemistry 
Geometry
TBD
Instrument Technology
High-resolution nadir-scanning SW spectrometer
Sampling
TBD
Data Access
Open Access
Data Format
TBD
Resolution
3 km by 4.1 km at nadir
Swath
From 55 degrees N to 55 degrees S
[Max Swath: 2500 km]
Accuracy
0.2% or 0.8ppm (whichever is greater) for
XCO2 as measured against time integrated
TCCON observations at multiple sites,
0.6% or 10.0 ppb (whichever is greater) for
XCH4 as measured against time integrated
TCCON observations at multiple sites,
10% or 10.0 ppb (whichever is greater)
for XCO as measured against time integrated
TCCON observations at multiple sites.
Retrieve estimates of solar induced fluorescence (SIF) from spectral measurements of the Fraunhofer lines near 758 nm and 770 nm with a NESR that is better than 0.5 mW/(m2 sr nm).
Waveband
0.76 µm, 1.61 µm, 2.06 µm, 2.32µm
GeoCarb - Geostationary Carbon Cycle Observatory (2025 - 2028) |