@article{white_aiyyer_russell_2021, title={The Impact of Orography on the African Easterly Wave Stormtrack}, volume={126}, ISSN={["2169-8996"]}, DOI={10.1029/2020JD033749}, abstractNote={AbstractWe examined the sensitivity of African easterly waves (AEWs) to elevated terrain over North Africa using a numerical weather prediction model. We formed five ensembles of simulated AEW activity with orographic features independently reduced in four key regions. The ensemble members consisted of 10 consecutive AEW seasons simulated separately. From the ensembles, the southern AEW stormtrack was most sensitive to the reduction of the Ethiopian highlands. Energy budgets showed that diminished diabatic heating associated with precipitating convection was the likely driver of the weaker AEWs. Baroclinic overturning was the dominant pathway for this response. The northern AEW stormtrack was most sensitive to the reduction of the Hoggar and Tibesti mountains. In this case, a reduction in the vertical shear and diminished baroclinic energy conversions from the background state was associated with weaker AEWs. Through terrain reduction, our results provide a view of thermodynamic and dynamic feedback in AEWs that is complementary to what has been shown in past studies.}, number={9}, journal={JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES}, author={White, J. D. and Aiyyer, A. and Russell, J. O. H.}, year={2021}, month={May} }
 @article{russell_aiyyer_white_hannah_2017, title={Revisiting the connection between African Easterly Waves and Atlantic tropical cyclogenesis}, volume={44}, ISSN={["1944-8007"]}, DOI={10.1002/2016gl071236}, abstractNote={AbstractAfrican Easterly Waves (AEWs) are the primary precursor for Atlantic tropical cyclones (TCs). We update the statistics on this relationship using reports from the U.S. National Hurricane Center. Sixty‐one percent of TCs originate directly from AEWs. Indirectly, AEWs are implicated in the formation of an additional 11% of TCs. AEW activity is quantified by eddy kinetic energy (EKE). The correlation between seasonal mean EKE and TC genesis is maximized in the lower troposphere below the southern AEW storm track, instead of where the canonical AEW is maximized. Therefore, midlevel AEW activity is a poor predictor of TC genesis, whereas its lower tropospheric circulation exerts stronger control. In most seasons, AEW activity is supercritical, and therefore, EKE is only a controlling factor in seasons when the low‐level EKE is weak. Predicting 1000–800 hPa EKE below the southern AEW track may be useful for seasonal TC prediction.}, number={1}, journal={GEOPHYSICAL RESEARCH LETTERS}, author={Russell, James O. and Aiyyer, Anantha and White, Joshua D. and Hannah, Walter}, year={2017}, month={Jan}, pages={587–595} }