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figures for high resolution pdf version Total Solar Irradiance
(TSI) Monitoring Figure 1 TSI monitoring by satellite
experiments Updated April, 2013 The Earth’s weather and climate
regime is determined by the total solar irradiance (TSI) and its
interactions with the Earth’s atmosphere, oceans and landmasses.
Evidence from both 34 years of direct satellite monitoring and
historical proxy data leaves no doubt that solar luminosity in
general, and TSI in particular, are intrinsically variable
phenomena. Subtle variations of TSI resulting from periodic
changes in the Earth's orbit (Milankovich cycles: ~20, 40 and
100 Kyrs) cause climate change ranging from major ice ages to
the present inter-glacial, clearly demonstrating the dominance
of TSI in climate change on long timescales. TSI monitoring,
cosmogenic isotope analyses and correlative climate data
indicate that variations of the TSI have been a significant
climate forcing during the current inter-gla