I’m interested in understanding how climate behaves on decadal to centennial timescales. My research focuses on paleoclimate, in particular the past 2,000 years (a.k.a the Common Era). I use paleoclimate reconstruction to understand the temporal evolution of temperature, and spatial patterns of the temperature field. The former puts the recent global warming argument in a broader context, and the latter lends insight into the understanding of dynamics of the climate system.
Instrumental temperature records are only available for the past 150 years or so. In order to get a longer history of temperature, we turn to proxies and look at how they express climate signals. We treat proxies as observations of past climate, and with the help of statistical tools we extract climate information of the past. This process is called reconstruction, and has been widely used in geosciences across all timescales.
As one may already see, the reliability of paleoclimate reconstructions rely largely on two aspects: proxy data being used and statistical methods being employed. How reliable is a climate reconstruction? To what extent can we trust the reconstructed climate? The answers are not simple. As a matter of fact, the shortness of instrumental data and incompleteness of proxy data make it insanely challenging to assess how well a reconstruction can be. Several strategies are proposed. In my research, I use pseudoproxy experiments to isolate the methodological impact, and proxy quality control experiment to evaluate the data impact.
Wang, J., Emile-Geay, J., Guillot, D., Smerdon, J.E.: Spatial Performance of Climate Field Reconstruction Techniques in a Realistic Pseudoproxy Context, in preparation.
American Geophysical Union, San Francisco, December 2011. Spatial Performance of Climate Reconstruction Techniques in a Realistic Pseudoproxy Context (Poster)
American Geophysical Union, San Francisco, December 2012. An updated pseudoproxy evaluation of four climate ﬁeld reconstruction methods using improved emulations of real-world conditions (Poster)
PAGES 4th Open Science Meeting and 2nd Young Scientist Meeting, Goa, India, February 2013 (with travel grand, but unable to go due to visa application)