Doctoral Defenses, Summer/Spring 2018

The following students recently completed Climate Dynamics Doctoral Defenses:

Zaiyu Wang

Zaiyu Wang, working with AOES faculty member Edwin Schneider, defended his dissertation “Understanding the role of coupling in climate simulations”. He showed how climate models develop bias because of errors in the model’s calculated depth of the ocean mixed layer. The mixed layer is a surface region of the ocean that interacts strongly with the atmosphere. Wang came to the doctoral program from the atmospheric science program at Nanjing University in the People’s Republic of China.

Mark Scafonas

Mark Scafonas’ dissertation was “The Role of Moisture in the Sensitivity of Baroclinic Life Cyle to Warming Conditions,” with AOES faculty member David Straus advising him. Scafonas studied the development of midlatitude weather systems that are either cyclonic (counterclockwise in the northern hemisphere) or anticyclonic (clockwise). His modeling experiments showed that, when effects of moisture are included, global warming will tend to increase a tendency for the Jet Stream to pinch off anticyclones. Before working on his PhD, Mark Scafonas received an MS in physics from Mason.

Jiexia Wu

Jiexia Wu, working with AOES faculty member Paul Dirmeyer, defended a dissertation on “Drought Demise Quantification and Attribution over CONUS”. She developed a new way to detect the end of a drought over the contiguous United States. She used this to measure how frequently droughts end due to tropical cyclones passing through an area, atmospheric rivers carrying water from the ocean to a region, or feedbacks between the land and atmosphere. To celebrate her defense, the atmosphere collaborated by delivering a major precipitation event on Virginia in the form of an unusual November snow storm. Jiexia Wu will be moving to the west coast, where she will be a post-doctoral associate at UCLA.

Holly Norton

Holly Norton, also working with Paul Dirmeyer, defended a dissertation on “Soil Moisture Memory (SMM) of Karst and Non-Karst Soils”. Karst is highly soluble geology underlying much of the surface of the United States. Soil moisture is an important parameter in land surface models that are coupled to atmospheric models to predict the exchange of moisture between the land and the air. Norton studied effects on soil moisture by water drainage through karst, and modified a land model to include these effects. Since February 2018 she has worked as a contractor for the NOAA Environmental Modeling Center (EMC) at National Center for Environmental Prediction (NCEP) where she will continue after her PhD.