My research focuses on Antarctic meteorology...below are synopses of current and past research projects...

McMurdo Dry Valleys Climate

    The McMurdo Dry Valleys comprise a unique polar desert ecosystem that is the largest ice-free region in Antarctica. The Dry Valleys are one of the most sensitive environments on Earth and thus are a bellwether of climate change for Antarctica, where detecting significant change has been difficult due to a lack of measurements and large variability on yearly-to-decadal timescales. This project has the goal of better understanding the complex climate of the Dry Valleys by employing atmospheric simulations from a high-resolution numerical model, Polar WRF, for a range of scenarios. Polar WRF is a version of the Weather Research and Forecasting model optimized for the environment of polar ice sheets by the Polar Meteorology Group.

Adélie Coast Cyclone Activity

    Previous studies have found the off-shore coastal region of Antarctica near 150˚ to feature frequent cyclogenesis.  However, the physical mechanisms responsible for cyclogenesis in this region have not been identified.  This project investigates cyclone development in this region for a three year period from 2003-2005 using the Antarctic Mesoscale Prediction System (AMPS).  An emphasis is placed on the influence of the prominent Adélie Land katabatic wind regime and the associated off-shore low-level wind regime.  Influence of the low-level wind regime towards cyclone development is found for over 50% of cyclogenesis events over the study period.  Composites and case studies are used to illustrate two distinct categories of cyclone development involving the low-level wind regime.  Cyclone statistics from AMPS and JRA-25 utilizing an automated cyclone tracking system are used to validate results from manual cyclone identification and to study aspects of cyclone climatology.  The dynamics of cyclone development and of the low-level wind regimes are studied to better understand the physical processes present in the region.

   

The May 2004 McMurdo Windstorm

    On 15-16 May 2004 a severe windstorm struck McMurdo, Antarctica.  The Antarctic Mesoscale Prediction System (AMPS) is used, along with available observations, to analyze the storm.  A synoptic-scale cyclone that propagates across the Ross Ice Shelf initiates a barrier jet along the Transantarctic Mountains.  The barrier jet interacts with a pre-existing near-surface radiation inversion over the Ross Ice Shelf to set up conditions favorable for the development of large-amplitude mountain waves, leading to a series of downslope windstorms in the Ross Island area.  Hydraulic theory can explain the structure of the downslope windstorms, with additional amplification of the mountain waves caused by wave-breaking events.  The underestimation of AMPS wind speed at McMurdo is caused by the misplacement of a hydraulic jump downstream of the downslope windstorms.  Misrepresentation of the flow regime in AMPS around Ross Island leads to the development of a mesoscale high-pressure anomaly over McMurdo, which influences location of the hydraulic jump.  The dynamics associated with the cyclone, barrier jet, and downslope windstorms are analyzed to determine the role of each in development of the severe winds.