EGU21-6437, updated on 04 Mar 2021
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

TSI and TOR measurements with CLARA onboard NorSat-1

Margit Haberreiter1, Wolfgang Finsterle1, Jean-Philippe Montillet1, Benjamin Walter2, Bo Andersen3, and Werner Schmutz1
Margit Haberreiter et al.
  • 1PMOD/WRC, Solar Physics, Davos Dorf, Switzerland (
  • 2WSL-SLF, Davos Dorf, Switerland
  • 3University of Oslo, Norway

Total Solar Irradiance (TSI) is one of the Essential Climate Variables (ECV) identified by the World Meteorological Organization's Global Climate System (GCOS). The Compact Lightweight Absolute RAdiometer (CLARA) experiment onboard the Norwegian micro satellite NorSat-1 is a SI traceable radiometer and was launched July 14, 2017 with the primary science goal to measure TSI from space. We present the latest status of the data and degradation correction obtained with this SI-traceable radiometer. Besides TSI, CLARA also measures the total outgoing radiation (TOR) at the top of the Earth atmosphere on the night side of Earth, which is extremely important to understand the Earth Radiation Budget. It is to our knowledge the first time that TSI and the emitted radiation from Earth are measured simultaneously with one SI-traceable absolute radiometer. We will compare the CLARA TSI and TOR time series with other available datasets. Ultimately, we aim towards determining the Earth Energy Imbalance from space. We will discuss the achievements and limitations in direction of this goal.

How to cite: Haberreiter, M., Finsterle, W., Montillet, J.-P., Walter, B., Andersen, B., and Schmutz, W.: TSI and TOR measurements with CLARA onboard NorSat-1, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-6437,, 2021.

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