October 18, 2006
American Center for Physics
College Park, MD
A generator in space, 150 million km away, heats the Earth, structures its atmosphere and organizes the surrounding space environment. The Sun's energy output changes continually, with myriad Earthly consequences. How much of recent surface warming and atmospheric ozone depletion are solar- rather than human-induced? Will a solar storm be deadly, for space instruments and astronauts alike? How might solar effects on navigation, communication and Earth-orbiting objects compromise security and commerce? Scientific curiosity and societal utility both call for a robust understanding of the Sun-Earth system - our home in space that extends well beyond the surface where we live.
Dr Lean is a research physicist in the Space Science Division of the Naval Research Laboratory. A US citizen since 1992, she earned a Ph.D. in Atmospheric Physics from the University of Adelaide, Australia (1982) and a Bachelor of Science (Hons) from the Australian National University (1975). 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 the Earth's global climate and space weather. She has testified to the US Congress on the role of solar output variations in climate change, and chaired the National Research Council's (NRC) Working Group on Solar Influences on Global Change and NOAA's NPOESS Solar Monitoring Study Group. She has also served on a number of NRC and NASA committees, including the NRC Board on Atmospheric Sciences and NASA's Living with a Star Science Architect Team. Elected a Fellow of the American Geophysical Union in 2002 and a member of US National Academy of Sciences in 2003, she is the author (or co-author) of over 100 papers in the scientific literature, and has made more than 200 presentations at scientific meetings, seminars, colloquia and lectures. A recent public lecture at the US Air and Space Museum on the Sun-Earth System is the basis for her talk on October 18.