Sun, Climate and Ozone: 1850–2100 with Judith Lean (University of Colorado, USA)

As Earth’s energy source and a variable star, the Sun has been credited over the past century with causing climate change that is a significant fraction of industrial-era warming… or so small as to be undetectable. Now, with more than forty years of space-based observations of solar irradiance and multiple geophysical quantities, and extensive advances in modelling solar irradiance and terrestrial variability, we can clarify with greater certainty the extent to which the Sun alters Earth’s environment, especially since 1850. This talk summarizes current observational evidence for the Sun’s role in global climate change and ozone-depletion recovery, and discusses the scientific (and societal) consequences of faulty detection and attribution.

Judith Lean is a senior scientist at the United States Naval Research Laboratory. She is a solar and climate scientist and her research focuses on the mechanisms and measurements of variations in the Sun’s radiative output at all wavelengths, and the effects of this variability on Earth, from the surface to space. Past Co-Investigator on UARS and SORCE missions. Testified to the US Congress on the role of solar output variations in climate change; chaired the National Research Council’s (NRC) Working Group on Solar Influences on Global Change. Served on multiple NSF, NOAA, NRC and NASA advisory committees. Author of more than 150 published papers and 300 presentations. Model reconstructions of solar irradiance variability have been used in multiple climate change simulations, including IPCC. American Geophysical Union Fellow (2002), US National Academy of Sciences member (2003), American Philosophical Society member (2013). Presidential Rank Award for Meritorious Senior Professional (2011).

Webinar is recorded in June 29, 2023