Aerosol Dynamics and their Contribution to Hurricane Sandy

Aerosols contribution to the formation, invigoration, and weakening of hurricanes has been investigated to some extent, but more research is still needed for a better understanding of their full role with regards to tropical cyclones. While many models and observations point to a general weakening affect, the ability for aerosols to invigorate a hurricane have also been observed. Aerosols have been known to enhance cloud formation, lifetime, and precipitation in appropriate quantities, and some can enhance upward convection and deep cloud formation. Hurricane Sandy has been identified as a hurricane that had additional aerosols supplied to its system via dust transport from a Saharan Dust event in an amount that is significant but not overloading, making it perfect to analyze for signs of invigoration/enhancement from aerosols. This is confirmed by monitoring a massive dust plume blowing off the western coast of Africa towards the Atlantic on October 8th, 2012 right before the development of Hurricane Sandy and along the path of Invest 99L. This makes us believe that dust aerosols capable of enhancing hurricane characteristics played a non-trivial role in the cyclogenesis process of Sandy. Many hurricane parameters are examined and evaluated, with an emphasis put on vertical profiles for temperature and aerosol distribution, although other factors such as humidity and wind shear are also considered and examined due to their importance. MODIS AQUA and TERRA, along with MISR, CALIPSO, and HYSPLIT, among other sources, are used for data gathering. While the exact extent of the effects of aerosols is beyond the scope of this work due to the presence of un-quantified systems such as the aerosol indirect effect on heating, there is strong evidence that sand from a Saharan dust storm event prior to hurricane formation was ingested into Hurricane Sandy which may have aided the cloud formation and upward convection necessary to a hurricane's genesis and growth. Increased AOD observed from the Moderate Resolution Imaging Spectrometer (MODIS), followed by increased precipitation and a decrease in cloud top temperature was observed.