A broad range of climate dynamics research motivated by extra-solar planet climate, current and past Solar System planetary climate, and deep-time Earth climate will be pursued. A common feature of this class of problems is the focus on collective behavior emerging from coupling of interesting fluid mechanical effects to interesting effects from novel radiative transfer, novel thermodynamics, or novel geochemistry. Specific problems include the effects of clouds and subsaturation on the runaway greenhouse, the climate of Super-Earths about M-dwarf stars, and the seasonal cycles of planets in highly eccentric orbits. Problems related to the Neoproterozoic climate of Earth include the effect of coupled dust/ice/climate evolution on deglaciation of the Snowball Earth, the dynamical effects of carbon-dioxide condensation, and the nature of the post-Snowball hothouse climate. In addition, several investigations bearing on anthropogenic Earth climate change will be carried out, including modeling related to the use of past mountain-glacier extent in paleothermometry, investigations of the physical nature of feedbacks leading to high climate sensitivity, and continued development of stochastic models of atmospheric humidity.
Broader impacts of this project include contributions to human resources development for addressing pressing problems in climate change on Earth. The novel and imaginative problems suggested by extra-solar planet climate are an effective way to motivate mathematicians, physicists and astrophysicists at all career levels to get involved in basic problems in atmospheric physics and dynamics. The demonstration of the universal applicability of basic physical principles across planets with diverse climates helps the public to build confidence in the physics on which forecasts of global warming are based; moreover, the curiosity-driven research on such problems can lead to unanticipated advances in things like radiative transfer modeling and can help shake loose new ideas that may relate to Earth climate. Finally, by contributing to the understanding of habitability, the research serves a deep-seated human need for exploration and understanding the place of humanity in the Universe, in much the same was as does research on cosmology.
