Dr. Simon H. Lee

Postdoctoral Research Scientist, Department of Applied Physics and Applied Mathematics, Fu Foundation School of Engineering and Applied Science

Postdoctoral Research Scientist, Ocean and Climate Physics, Lamont-Doherty Earth Observatory (LDEO)

Columbia Climate School



I am a Postdoctoral Research Scientist in the Department of Applied Physics and Applied Mathematics (APAM), working with Lorenzo Polvani. I moved to Columbia in November 2021 after completing my PhD at the University of Reading, UK, where I also studied as an undergraduate.

I work on stratosphere-troposphere coupling, large-scale climate dynamics and variability, and subseasonal-to-seasonal prediction. I am also Co-Editor-in-Chief of the Royal Meteorological Society journal Weather.


Nov 23, 2023

The importance of the polar vortex at 100 hPa

The most commonly-used diagnostic of the strength of the stratospheric polar vortex is the zonal-mean zonal wind at 10 hPa (~30 km) and 60°N (U10-60), which is westerly during winter. It is an easy diagnostic to compute and understand, which probably helped drive its uptake. Reversals of U10-60 to easterlies indicate either a major sudden …

Nov 03, 2023

What’s that coming over the hill, is it a weak vortex?

Only a few years ago, ECMWF’s then-twice-weekly 51-member extended-range forecasts were not publicly available — something that is almost hard to comprehend nowadays, as we have daily, 101-member ensemble forecasts available for free on the ECMWF website. The ensemble size is spectacular, and increases forecast reliability. But I’m more interested in what we gain from …


An up-to-date list of my publications can be found here.