Current Projects

My research thus far has fallen into two general categories. I have examined precursors of wintertime stratospheric polar vortex variability. I have found that ENSO significantly affects the polar vortex by enhancing tropospheric wave-1 through its canonical teleconnection pattern in the North Pacific. High anomalies over Eastern Europe also constructively interfere with the climatological planetary waves and enhance wave driving of the polar vortex, leading to the effect of October Eurasian snow cover on the vortex. The influence of tropospheric variability on the vortex is of comparable magnitude to the influence of the QBO on the vortex. Variability of the polar vortex affects wintertime surface weather, and thus a better understanding of polar vortex variability is of use to forecasters.

More recently, I have examined the influence of the QBO on tropospheric variability. EQBO leads to a weaker El Nino teleconnection in the North Pacific than WQBO. Even in the absence of anomalous sea surface temperatures, the QBO seems to lead to a horseshoe shaped pattern response in the North Pacific. This horseshoe response is present in both a dry dynamical core and in a more complex climate model, and arises from the interaction between the thermal wind balanced meridional circulation of the QBO and tropospheric eddies. This horseshoe can then alter the propagation and the subsequent extratropical growth of the wavetrain associated with anomalous ENSO convection, potentially explaining how the QBO can modulate ENSO teleconnections.











The difference plot and climatology. The movie .