| TC structures consisting of eye, eyewall and rainband can be clearly resolved by Microwave Humidity Sounder (MHS) window channels. High brightness temperatures are found in cloud-free hurricane eye and cloud streaks, and low brightness temperatures are found in cloud rainbands. In this study, MHS is used to estimate TC center and radius of maximum wind. The TC center location is determined by the warmest brightness temperature of MHS channel 2 within TC eyewall region. The radius of maximum wind is estimated based on the radial profiles brightness temperatures calculating at six-degree azimuthal angles. The shortest distance between the hurricane center and the minimum point of brightness temperature with some minimum points on its neighboring radial profiles is taken as the estimate of the radius of maximum wind. This method for estimating the TC center location and the radius of maximum wind was applied to twelve arbitrarily selected TCs that occurred in 2010, 2011 or 2012 over Atlantic basin. More than 78% of cases have the differences of TC center location and radius of maximum wind between MHS and NHC being less than 15 km and 10 km, respectively. The infrared observations from Advanced Very High Resolution Radiometer (AVHRR) on board the same satellite as MHS are also used for further comparison. It was found that the large differences between MHS estimate and Best Track analysis seem to occur for TCs with asymmetric structure or high-latitude locations. |
