Observations of infrared sea surface temperature and air-sea interaction in Hurricane Edouard (2014) using GPS dropsondes

Abstract

his study highlights infrared sensor technology incorporated into the Global Positioning System (GPS) dropsonde platforms to obtain sea surface temperature (SST) measurements. This modified sonde (IRsonde) is used to improve understanding of air-sea interaction in tropical cyclones (TCs). As part of the Sandy Supplemental project, IRsondes were constructed and then deployed during the 2014 hurricane season. Comparisons between SSTs measured by collocated IRsondes and ocean expendables show good agreement, especially in regions with no rain contamination. Surface fluxes were estimated using measurements from the IRsondes and AXBTs via a bulk method that requires measurements of SST and near-surface (10 m) wind speed, temperature and humidity. The evolution of surface fluxes and their role in the intensification and weakening of Hurricane Edouard (2014) are discussed in the context of boundary-layer recovery. Our result emphasizes the important role of surface-flux induced boundary-layer recovery in regulating the low-level thermodynamic structure that is tied to the asymmetry of convection and TC intensity change.