Solar Constant
Total Solar Irradiance (TSI) has been monitored with absolute radiometerssince 1978 onboard five different satellites:
- Hickey-Frieden (HF) radiometer onboard the NIMBUS-7 spacecraft:16.11.78 - 24.01.93
- ACRIM I onboard the Solar Maximum Mission (SMM) spacecraft: 14.02.80- 01.06.89
- Absolute radiometer onboard the Earth Radiation Budget Satellite (ERBS):since 25.10.84
- ACRIM II onboard the Upper Atmosphere Research Satellite (UARS):since October 1991
- DIARAD and PMO6-V absolute radiometers of VIRGO onboard the SOHOspacecraft: since 18.01.96
Each time series was corrected for sensitivity changes and operationalinfluences as described in Fröhlich and Lean (1998) and shown below.
Total Solar Irradiance Data
Image: Postscript In order to compose a uniform TSI time series, the different time series have to be homogenized and adjusted to a common scale (Space Absolute Radiometric Reference). The result is shown in the Figure below.
Total Solar Irradiance Data
Image: Postscript |
PDF ASCII: Data File
Reference: Fröhlich, C. and Lean, J.: 1998, Total solar irradiance variations: The construction of a composite and its comparison with models,
in F. L. Deubner (ed.),
IAU Symposium 185: New Eyes to See Inside the Sun and Stars, Kluwer Academic Publ., Dortrecht, The Netherlands, pp. 89-102, 1998. (
preprint as postscript file).
See also: >>The VIRGO homepage >>VIRGO Total Solar Irradiance 
