The article interviewed Colorado State University (CSU) scientist Eric Maloney, and wrote “Bohar Singh, an atmospheric scientist who works with Maloney at CSU, described evidence from CYGNSS that persistent winds boost ocean evaporation under a 3000-kilometer-wide set of rainstorms, sustaining them. That finding could help scientists forecast how the storm belt will change in a warmer climate, Maloney says.”
The book is based on Mason graduate course CLIM 752 Ocean General Circulation. Klinger also teaches an introductory course, CLIM 412/512 Physical Oceanography. While ocean currents are changing all the time, there is an underlying pattern of permanent current systems which can be found in all the oceans. These patterns have been uncovered by millions of oceanographic measurements from ships, buoys, and satellites, and can be explained from physical principles. The circulation affects not only the oceans themselves but also the global climate, because currents redistribute heat and other properties across the globe, changing atmospheric temperature and circulation. The book explores each circulation structure, demonstrating where in the ocean it can be found and explaining what determines its behavior.
Eos, the online news site and magazine for American Geophysical Union (AGU), has a Research Spotlight article Role of Humans in Past Hurricane Potential Intensity is Unclear on work by AOES Faculty Laurie Trenary and Tim DelSole and their collaborators.
Human-induced Global Heating is expected to intensify hurricanes in the future, so the question of how much stronger and more damaging hurricanes will become has generated great interest among scientists and policymakers. A related question is whether past warming is responsible for recent increases in Atlantic hurricane intensity. Trenary et al. show that different climate models give inconsistent changes in hurricane potential intensity when driven by increases in greenhouse gases. Thus it is not possible yet to attribute changes in hurricane intensity to human activity.
“When Whales Walked: Journeys in Deep Time”, features top paleontologists studying Earth’s majestic creatures, including AOES Associate Professor Dr. Mark Uhen. The special premieres on PBS June 19th at 9/8c, and the trailer can be found here.
AOES Climate Scientists have been busy recently informing the Northern Virginia public about global warming.
Jagadish Shukla and Jim Kinter spoke at Climate 3.0: The Science, the Politics, and the Policy Agenda. The event, moderated by Washington Post columnist and Mason professor Steven Pearlstein, also featured talks by President Cabrera and faculty from the Communications Department, the Mercatus Center, and other departments.
The Washington Post printed Barry Klinger’s letter to the editor on carbon emissions in the US and around the globe.
Jim Kinter gave talks about The New Normal of climate change to audiences at the Metropolitan Washington Council of Governments, the Northern Virginia Regional Council, and elsewhere in Virginia. Dr. Kinter was also a panelist along with two Virginia Assembly Delegates at “The Ice Melts” event at, organized by honors undergraduate students at George Mason University.
Shukla and Klinger also gave short talks on climate at the “Breaching Waterways: Along the Anacostia River”, a performance piece by Mason performance artist Katie Kehoe.
The American Geophysical Union recently shined a research spotlight on AOES affiliate scientist Rocio Caballero Gill. Caballero-Gill and AOES faculty member Linda Hinnov analyze ancient sediments for clues about the evolution of climate in the past. In her paper with colleagues from Brown University and the US Geological Survey, Caballero-Gill found evidence of a 100,000 year cycle during the Pliocene Epoch, the period of geological history that lasted from about 5.3 to 2.6 million years ago. The cycle they document may be an important component in the pacing between ice ages and interglacials during the Pliocene.
Two students successfully defended Climate Dynamics Doctoral Dissertations in Spring 2019. For full abstracts, see AOES Seminar Pages.
Akiko Elders, working with AOES faculty member Kathy Pegion, investigated the relationship between weather and Arctic sea ice decline. The Arctic is warming faster than other regions of Earth, resulting in a dramatic decline in sea ice. Sea ice decline may be linked to extreme winter whether in mid-latitude regions such as the United States. Elders used a state-of-the-art climate model to separate the impacts on mid-latitude weather of global warming and sea ice decline.
Liang Yu, whose advisor was AOES faculty member Bohua Huang, studied components of Atlantic Multidecadal Variability (AMV). AMV is the tendency of the North Atlantic to be colder or warmer than average for decades at a time, causing large-scale changes in climate during these periods. The phenomenon is poorly understood but thought to be related to interactions between ocean currents and the atmosphere. The atmosphere can drive ocean variability through the exchange of momentum (by wind pushing on the sea surface), heat (cooling and heating the sea), and freshwater (evaporation and precipitation). In a coupled atmosphere-ocean climate model, all three exchanges vary simultaneously. Yu studied the separate effect of each influence by conducting experiments with an ocean circulation model in which each forcing (wind, heat, and water) from the coupled model was applied separately.
Twenty seven graduate students from across the US presented their work to over 50 students and faculty. The theme of “Earth Systems Modelling” included talks on climate change on the scale of months and of decades, melting of the Greenland Ice Sheet, predicting drought in east Africa, use of machine learning in subseasonal forecasting, and the influence of the tropical Madden-Julian Oscillation on midlatitude rainfall. Jagadish Shukla (George Mason University) and Ben Zaitchik (Johns Hopkins University) gave Keynote Lectures.
Much of the planning and organization of the symposium was done by Climate Dynamics PhD students Teresa Cicerone, Olivia Gozdz, and Nicholas Lybarger, who were advised by Research Assistant Professor Laurie Trenary. As Dr. Trenary remarked, “It was really great to see that level of student engagement, to hear the discussions and questions. This is a good opportunity for students – I hope we can find a way to keep it going.”
Clustering techniques identify discrete groups of atmospheric and oceanic structures that occur more frequently than would be expected based on a background distribution, such as a multivariate Gaussian distribution. Some of the techniques identify states that are also unusually long-lived (or persistent).
Examples of atmospheric states identified from cluster analysis include seasonal-mean midlatitude response patterns to El Niño events, and the North Atlantic Oscillation and the Pacific–North America patterns. On weather timescales, cluster analysis has been used to objectively identify a number of typical synoptic patterns familiar to forecasters.
Dr. Straus’s research has applied cluster analysis to better understand the effects of sub-seasonal tropical heating on mid-latitude circulation, and to help categorize extreme precipitation events over North America.