My research interests cover broad areas in present, past and planetary climates. We aim at studying fundamental and frontier problems of Earth and planetary climates. My philosophy is to treat the Earth climate as an integrated and dynamic system, which receives energy from solar radiation, dynamically evolves throughout fluid motions, and involves the interplay of the atmosphere and ocean with the interior of Earth. My approach to these problems is to combine observational data analyses, numerical simulations, and theoretical studies.
For the present-day climate, I am interested in how changes in atmospheric compositions due to human activities may lead to changes in atmospheric circulations and climate. Especially, I focus on climate dynamics of the troposphere, stratosphere, ozone layer, and their interaction.
I have great enthusiasm in deep-time paleoclimate. Through Earth's 4.6 billion-year history, the climate system had varied between cold and warm eras, such as the cold Paleoproterozoic and Neoproterozoic global ice ages (Snowball Earth) and the Cretaceous global warming. Our own Earth also experienced boring eras, such as the Boring Billion between 1.8 and 0.8 billion years ago. Studying climate changes in the past will not only benefit our understanding of the history of Earth evolution but also help our understanding of global climate changes at present.
Considering Earth as a planet, we would wonder why our own Earth maintains habitable, while Venus and Mars are uninhabitable. Some evidence suggests that liquid water ever existed over Venus and Mars in their early time. If it is true, Venus must experience runaway greenhouse, and Mars fell in runaway freezing some time ago. Studying climate changes over these planets benefits us in understanding Earth’s climate evolution in the deep-time history.Searching for habitable exoplanets and extra-solar life has been an intriguing dream for human. More than 4000 exoplanets have been discovered so far, and 10-20 are potentially habitable. The discoveries rises up great challenge to our traditional understanding of the formation of the solar system. How to determine the habitability of exoplanets, and how to detect extra-life? These are the questions that we have engaged in the past decade.