Reprocessing the “Top Ten” Most Intense Historical Tropical Cyclones in the Satellite Era Using the Advanced Dvorak Technique

In recent years, a number of extremely powerful tropical cyclones (TCs) have revived the community debate on estimating maximum intensity, and how they rank in the satellite era. In most cases, satellite estimates are relied on heavily by Regional Specialized Meteorological Centers tasked with conducting post-analyses of TC Best Tracks. The Dvorak Technique is the primary satellite tool for analyzing intensity, but the method has limitations and depends somewhat on analyst judgement (Velden et al. 2006). Dvorak also did not have the full range of satellite capabilities when developing his method, so there may also be inherent biases in the empirical method's estimates, particularly notable at the very strong end of the TC intensity spectrum (Knaff et al. 2010).

The Advanced Dvorak Technique (ADT; Olander and Velden 2009) is an objective approach that builds on the principles of the Dvorak Technique, but has also been enhanced by rigorous statistical analysis and capabilities that fully exploit the improved complement of satellite data available today. The ADT is now operational at NOAA/NESDIS, and serves as a practical tool for aiding TC forecasters in real-time and post-analysis intensity estimation. The ADT has also been employed in TC historical reprocessing efforts (Kossin et al. 2013). However the intent in this application was for the purposes of homogenization and intensity trend analysis, rather than a focus on absolute maximum intensities.

In this study, we will employ the most updated and fully-capable version of the ADT algorithm and apply it to the highest resolution (spatial and temporal) satellite data available for selected extreme-intensity TCs over the globe during the satellite era. Cases with recon aircraft verification of intensity will initially be examined and if necessary used to more carefully calibrate the ADT at extreme intensities. Bias corrections for observing properties such as satellite viewing angle and image resolution, and storm characteristics such as small eye size will be considered. The project's end goal will be an objective satellite-based assessment of maximum lifetime intensity for the most powerful TCs in the satellite era, with hopes of providing some insight towards the global all-time “Top Ten” debate.