Downwelling (Incoming) solar radiation at TOA Measurement Instruments

Measurements > Atmosphere > Radiation budget > Downwelling (Incoming) solar radiation at TOA
Measurement Definition: Flux density of the solar radiation at the top of the atmosphere - Physical unit [ W/m2 ], Accuracy unit [ W/m2 ]

Thematic Links
InstrumentStatus/
Accuracy		Instrument DescriptionMeasurement TechnologyTimeline
CERESOperationalLong term measurement of the Earth's radiation budget and atmospheric radiation from the top of the atmosphere to the surface; provision of an accurate and self-consistent cloud and radiation database.n/a
CLARAOperationalCLARA is a scientific instrument that will be used to determine the total solar irradiance of the Sun.n/a
GOME-2OperationalMeasurement of total column amounts and stratospheric and tropospheric profiles of ozone. Also amounts of H20, NO2, OClO, BrO, SO2 and HCHO.n/a
SIM-2OperationalSIM-2 uses solar irradiance absolute radiometers to measure total solar irradiance.n/a
SIM-3OperationalSolar irradiance monitoring.n/a
SSIMOperationalSSIM measures continuous solar spectrum from 165nm to 2400nm.n/a
TSIS-1/SIMOperational
+/-0.2 %
Measures solar spectral irradiance in the 0.2 - 2 µm range.n/a
TSIS-1/TIMOperational
+/-0.035 %
Measurement of total solar irradiance directly traceable to SI units with an absolute accuracy of 0.035% and relative accuracy of 0.002% per year.n/a
FEIBeing developedProvide images in a narrow spectral band centered at 10.5µm.n/a
GXIBeing developedDetects clouds, cloud properties, water vapour, land and sea surface temperatures, dust, aerosols, volcanic ash, fires, total ozone, snow and ice cover, vegetation index.n/a
TSIS-2/SIMBeing developed
+/-0.5 %
Measures spectral solar irradiance over three bands ranging from 200 to 2400 nm.n/a
TSIS-2/TIMBeing developed
+/-0.02 %
Measures total solar irradiance over the full spectrum.n/a
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