Chapters authored
Evaluating the Progress of Atmospheric Research in Understanding the Mechanics Behind Tropical Cyclone-Induced Tornadogenesis
As tropical cyclones make landfall along coastlines all over the world, havoc is wreaked on families, businesses, economies, etc. A generally overlooked topic is one of the inherent dangers in tropical cyclone landfalls. These can produce tornadoes in the spiral rain bands coming ashore by encountering increasingly higher frictional convergence. The second component will be assessing which other parameters could be analyzed on a synoptic timescale to evaluate how we can potentially improve longer term predictions of tropical cyclone (TC)-induced tornadogenesis. The analysis showed that the combination of high low-level moisture, vertical temperature gradients, and enhanced vertical wind shear is the key factor that links landfalling tropical cyclones to associated tornadogenesis prior to, during, and/or after the time of landfall. An integral part of the process preceding TC-induced tornadogenesis is the enhanced vertical temperature gradient that develops as the storm maintains warm-core characteristics aloft but develops cold-core characteristics closer to the surface. The examination of forecaster perspectives showed that over the past few years there is strong evidence of forecaster improvement based upon greater cognizance of forecast variables linked to TC-induced tornadoes.
Part of the book: Tropical Cyclone Dynamics, Prediction, and Detection
The Interannual and Interdecadal Variability in Tropical Cyclone Activity: A Decade of Changes in the Climatological Character
During the last decade, there has been concern that the frequency or intensity of tropical cyclones (TCs) has increased. Also, climate models have shown varying results regarding the future occurrence and intensities of TC. Previous research from this group showed there is significant interannual and interdecadal variability in TC occurrence and intensity for some tropical ocean basins and sub-basins. This work examines global TC occurrence and intensity from 2010 to 2019 and compares this period to the same quantities from 1980 to 2009. The data used here are obtained from publicly available TC archives. Globally, the number of TC occurring over the latest decade is similar to the previous decade. However, while the 40-year trend shows an increase in TC, only intense hurricanes have shown an increase. The Atlantic Ocean and North Indian Ocean Basins show increases in TC activity, especially intense storms. The Southern Hemisphere and West Pacific Region show decreases in TC activity. In the West Pacific, intense TC did not increase, but the fraction of storms classified as intense increased. Only East Pacific TC activity showed no significant short- or long-term trends. Interannual and interdecadal variability in each sub-basin was found and there were some differences with previous work.
Part of the book: Current Topics in Tropical Cyclone Research