Atmospheric Wave Interactions and Hurricane Formation

University of Miami

Advisor: Dr. Sharanya Majumdar

Funding Sources: NSF Graduate Research Fellowship, University of Miami Dean's Fellowship

Years Active: August 2019 - Present

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Tropical cyclones (TCs) that form in the Atlantic basin can have devastating impacts on communities. The predictability of these TCs is heavily influenced by the basic processes that govern their formation (or “genesis”). While genesis is thankfully infrequent, certain features can make it more likely. In the Atlantic basin, support is often provided by African Easterly Waves (AEWs); around 61% of TCs in the Atlantic are the direct result of AEWs [1].  Furthermore, recent studies have indicated that another kind of atmospheric wave -- Convectively-Coupled Kelvin Waves (CCKWs) -- can also have impacts on tropical cyclone formation [2][3]. 

For my PhD research at the University of Miami, I am studying the interactions between AEWs and CCKWs in the Atlantic and their impact on hurricane formation. One way I am doing so is via ERA5 reanalysis data. I also will be collaborating with researchers at NOAA's Hurricane Research Division (HRD) to study aircraft observations of hurricane formation during these wave interactions. Ultimately, I hope to better illuminate how interactions between AEWs and CCKWs can make hurricane formation more or less likely, and better understand how predictable these processes might be!

Below Animation: Animation of convection (grey contours, 700 hPa "omega") associated with an African Easterly Wave (center and track given by star and black line, respectively) as it moves through a Kelvin wave (CCKW). The Kelvin wave is represented by the background contour shading, with blue-like shading indicating the convectively-favorable phase of the CCKW, and red-like shading indicating the convectively-suppressed phase. 

[1] Russell, A., et al., Geophys. Res. Lett., 44, 1 (2017)

[2] Schreck, C. J. III, 2015: Kelvin Waves and Tropical Cyclogenesis: A Global Survey, Mon. Wea. Rev., 143, 3996-4011.

[3] Thorncroft, C. D. and A. Brammer, 2016: On the Influence of Convectively Coupled Kelvin Waves on African Easterly waves. 32nd Conference on Hurricanes and Tropical Meteorology, AMS.

Presentations

Take a look at the poster I presented on this project during the 2021 American Meteorological Society Virtual Conference!

  • Lawton, Q. A., S. J. Majumdar, K. Dotterer, and C. Thorncroft, 2021: Tropical Cyclogenesis via Convectively Coupled Kelvin Wave (CCKW) – African Easterly Wave (AEW) interactions. Part II: AEW Behavior during the 2020 Atlantic Hurricane Season. American Meteorological Society’s Fourth Special Symposium on Tropical Meteorology and Tropical Cyclones Poster Session, Virtual.

  • Dotterer, K., C. Thorncroft, Q. A. Lawton, and S. J. Majumdar, 2021: Tropical Cyclogenesis via Convectively Coupled Kelvin Wave (CCKW) – African Easterly Wave (AEW) interactions. Part I: CCKW Behavior during the 2020 Atlantic Hurricane Season. American Meteorological Society’s Fourth Special Symposium on Tropical Meteorology and Tropical Cyclones Poster Session, Virtual.

  • Walker, A., G. Rizzuto, Q. A. Lawton, and S. J. Majumdar, 2021: Large-Scale Environmental Influences on African Easterly Waves and Tropical Cyclogenesis in the Eastern Atlantic Basin. 2021 American Meteorological Society Student Conference, Virtual.