Over the continental US, the diurnal elevated heating over the Rockies generates potential vorticity anomalies that are advected downstream. Our observational and theoretical study suggests that these drifting PV anomalies are related to the movement and systematic regeneration of MCSs over the Great Plains and Midwest. These organized convective events play an important role in regional warm season rainfall climatology.

Evaluation of recent extremes in high northern latitude temperatures is better undertaken in the longer term context afforded by the paleoclimate record. Determining the probability that an event like the 2010 Russian heat wave is unprecedented requires a statistical treatment that permits for the imputation of temperatures in space, accounts for uncertainties in the instrumental and proxy observations, and permits for a probabilistic assessment of extreme values.

Chlorofluorocarbons (CFCs) were a triumph of the chemical industry and a mere curiosity in atmospheric science when Sherwood (Sherry) Rowland, with his postdoc Mario Molina, recognized in 1973 that these seemingly inert gases posed a threat to Earth's ozone layer. Returning home one evening, Rowland remarked to his wife Joan that the research “is going very well, but it may mean the end of the world”.

Instructional Presentation