Current Research Projects

Rossby wave propagation and extreme events

Collaborators: Virginie Guemas, Barcelona Supercomputing Center; Dr. Chloe Prodhomme, University of Barcelona; Dr. Georgios Fragkoulidis, Johannes Gutenberg-Universit├Ąt Mainz; Prof. Libby Barnes, Colorado State University

During my Marie Sklodowska-Curie Individual Fellowship at the Barcelona Supercomputing Center, Spain I initiated this project studying the connections between Rossby wave propagation and extreme weather events such as heat waves, cold snaps, heavy precipitation events, and droughts. By studying the seasonal predictability of Rossby wave propagation pathways, we are studying how this may be used to provide enhanced seasonal predictability of the probability of extreme events. A short conference paper on the atmospheric waveguide detection algorithm I have developed as part of this work can be found here.

The Climate of the Last Glacial Maximum

Collaborators: Prof. Qiang Fu, Prof. Becky Alexander, Prof. David Battisti, Mingcheng Wang, Uni. of Washington

We are using the WACCM6 model to study the impacts of Last Glacial Maximum (LGM) geometry (in particular the Laurentide ice sheet) and chemistry changes on atmospheric circulation and chemistry, in contrast with present day and pre-industrial conditions. I have run simulations with the WACCM6 model in an LGM configuration to study tropospheric and stratospheric dynamics and chemistry in the LGM.

Mountains and climate

Collaborators: Prof. David Battisti, Prof. Mike Wallace, Casey Hilgenbrink, Uni. of Washington; Dr. Jane Baldwin, Columbia University; Prof. Aditi Sheshadri, Stanford University

Using state-of-the-art general circulation models (the CESM, WACCM, and ECHAM models) we are revisiting the research question of how, and by how much, do the mountain ranges of Earth affect our climate, including atmospheric circulation, climate variability, and ocean dynamics. During this project we have found some surprising results, including the importance of the Mongolian mountains of Asia relative to the higher and more extensive Tibetan plateau and Himalaya; this is true for wintertime circulation over the Pacific as well as stratospheric circulation and Sudden Stratospheric Warmings.. A paper currently in preparation looks at the roles different mountain regions play in affecting the climate of the North Atlantic and western Europe, including on the Atlantic Meridional Overturning Circulation (AMOC); the large-scale ocean circulation bringing warm water to the North Atlantic.

Recent Research Projects



Cross-equatorial heat fluxes and ITCZ shifts: sensitivity to forcing location.

Collaborators: Prof. Dargan Frierson, Prof. Cecilia Bitz, Ashly Spevacek, Uni. of Washington; Prof Sarah Kang, Ulsan National Institute of Science and technology

Together with Dargan Frierson, Cecilia Bitz, and Ashly Spevacek, we were awarded an NSF grant to study the impacts of forcing location on cross-equatorial heat fluxes, and associated ITCZ shifts. By placing anomalous surface heat fluxes in localized region of coupled GCMs, we are exploring the ocean and atmospheric thermodynamic response to these forcings.

Tracking Precipitation Events

Collaborators: Prof. David Battisti, Uni. of Washington; Dr. Gregor Skok, Uni of Ljubljana.

Used an event-tracking algorithm we track all events in the TRMM 3B42 3-hourly precipitation data, as well as 3-hourly ERA-interim precipitation from 1980-2015. We find an increase in the number of events that last 1-2 and 2-5 days over the lifetime of the TRMM satellite. More details, including access to the event tracking code, output data, analysis code, and some results can be found here.