AOS & CICS Newsletter

Spring/Summer 2010 Volume 4, Number 2

“During my time here, I’ve had a chance to Gnanadesikan interact with biological, physical and chemical oceanographers, atmospheric Moving On After 15 dynamicists and chemists, terrestrial Program in Atmospheric and ecologists and mechanical engineers. Oceanic Sciences (AOS) & Years Princeton is an outstanding place to get a The Cooperative Institute for broad view of how our planet works.” Climate Science (CICS)

“Anand is tireless in his dedication to discovery. He’s passionate about the Inside this issue:

development of climate models and their Gnanadesikan Moving On.………….1 continuous evolution,” AOS Director Jorge

Sarmiento said. “Not only is he a Oey’s Research Featured in dedicated scientist, he is an esteemed Interview………………………………….1 colleague and mentor to his students. He

will be sorely missed.” Jerry D. Mahlman Lobby is Dedicated…………………………………2 Regarding continuing collaborations at GFDL and Princeton, Gnanadesikan said, SEAS-AOS-GFDL Workshop…………2 “I also anticipate continuing the

GFDL Oceanographer & AOS Lecturer collaborations I’ve been fortunate enough Conference “Empowers” Women Anand Gnanadesikan to build here in the past fifteen years, and in Science…………………………………3 hope to be able to build new bridges to the paleoclimate and observational Rossi and Slater Honored……………3 After 15 years at Princeton, GFDL communities. I look forward to our Oceanographer and AOS Faculty Member continuing to learn about the planet GFDLEA Annual 5K Race…………….4 Anand Gnanadesikan has accepted a together!” tenured associate professor position at the Research in Action…………………….4 Earth and Planetary Sciences Department Outside of work, he is extensively involved at Johns Hopkins University. He will in outreach though programs such as AOS & CICS News……………………..5 begin his appointment in January, 2011. Science Olympiad, the largest national team science competition for secondary Gnanadesikan’s research interests focus on schools, and through working with understanding the mechanisms that drive museums to help bring up-to-date science Oey’s Research the large-scale physical circulation of the into exhibitions. ocean and the impact of changes in this Featured in Times circulation for climate, ocean chemistry, Gnanadesikan earned his undergraduate and ecosystems. Using general circulation degree in Physics from Princeton of Trenton models of the ocean and atmosphere and University and his Ph.D. in Oceanography examining how these simulate not only the from the Joint Program in Oceanography at MIT/Woods Hole Oceanographic Interview physical climate, but quantities such as radiocarbon, oxygen, and nutrients, has led Institution. ■ AOS Researcher Leo Oey was featured him to look at how human activities might June 14 in The Times of Trenton in an TigerTransit/Shuttle Services perturb the carbon cycle. Over the years, interview addressing the BP oil spill. he has been very involved in the Operating on development of new models at GFDL, Summer Schedule: The article discussed the overlap between including ocean-only models, coupled http://www.princeton.edu/transportatio Oey’s work in ocean modeling and the ocean atmosphere models, and models of n/ForrestalSummer10.pdf estimated distribution of oil from the spill. biogeochemical cycling. Using the Princeton Ocean Model (POM), co-developed by Oey, George Mellor, and The article in its entirety can be found at: Alan Blumberg in the early eighties, Oey http://www.nj.com/mercer/index.ssf/2010/ and his research team entered thousands of 06/gulf_view_not_a_pretty_picture.html ■ simulated particles at the coordinates of the spill site and had the computers crunch out the data of how those particles are likely to move and spread over time. Jerry D. Mahlman

Lobby is Dedicated

On Tuesday, May 4th, 2010 the newly renovated GFDL lobby was named the “Jerry D. Mahlman Lobby,” in honor of Jerry Mahlman, former director of GFDL and lecturer with rank of professor in the Jerry Mahlman, former director of GFDL and AOS Program. The dedication ceremony lecturer with rank of professor in the AOS was attended by Jerry’s and Janet’s Program daughter, Julie, and the many friends and colleagues who had the pleasure of From 2000-2009, Mahlman was a senior AOS Researcher Leo Oey working with Jerry throughout the years. research associate at the National Center “What we did was to release (simulated) for Atmospheric Research. In recent years, particles at the spill site and we track that he has been centrally involved in the in time for weeks, for months [sic],” Oey communication of climate change science told the Times. “And we throw in many to a wide variety of audiences, and assists particles and then we do some statistical in guiding the international policy analysis to average them and get a sense of deliberation process through the where those particles might go.” interpretation of climate science.

"There's a big assumption, of course: We During the span of his illustrious career, assume that the oil will also follow the Mahlman published over 100 scientific particles' movements. They generally do, papers. Among his many awards, he but not exactly," Oey said in the article. received the U.S. Department of He cautioned that long range ocean Commerce Gold Medal in 1986, the modeling isn’t specifically equipped to Jerry and Janet Mahlman’s daughter, Julie, at American Geophysical Union First Annual th predict the movement of an oil spill, the May 4 lobby dedication Jule G. Charney Lecturer Award in 1993, because the models don’t calculate in the Mahlman’s NOAA career began on the day the Presidential Distinguished Rank Award properties specific to oil. Instead, the agency was created, October 3, 1970 in 1994, and the highest honor given by the modeling focuses on historical data of when he joined Joseph Smagorinsky and American Meteorological Society, the current locations and shifts, as well as wind Syukuro (Suki) Manabe in their pioneering Carl-Gustaf Rossby Research Medal, in patterns that affect ocean currents. efforts to develop atmospheric circulation 1994. models at GFDL. During his three decades In discussing the Loop Current, a high- at GFDL, Mahlman was a pioneer in Mahlman received his undergraduate speed stream that pulses north into the Gulf stratospheric dynamics and chemistry as degree from Chadron State College in 1962 of Mexico and travels in a clockwise well as numerical modeling. He added and earned his Ph.D. from Colorado State pattern toward Florida, Oey told the Times significantly to the understanding of how University in 1967. ■ that the POM estimates that, at most, 10 climate works and spent much of his career percent or so of the surface particles that modeling how Earth's atmosphere responds originate at the spill site could get caught to the steady buildup of greenhouse gases. SEAS-AOS-GFDL up in the main Loop Current and Gulf Stream. He added, however, that this Under Mahlman’s tenure as director, Workshop held on figure is a worst-case scenario. GFDL continued to recruit highly talented scientists and provide an intellectually Main Campus He also noted that despite the model’s stimulating environment for them, a sophistication, the forecasting done thus far tradition begun by Smagorinsky, the lab’s A Student-Postdoc workshop on Fluid via the POM has focused on what happens first director. “I am proud that we are able Dynamics & the Global Environment was at or near the surface; it doesn’t take into to attract, nurture and retain these young held at the Friend Center on Friday, May account the oil plume at depth. In response, scientists,” Mahlman said just prior to his 21st, with some 35 people in attendance. Oey and his team are beginning to examine retirement from GFDL in 2000. Today, The workshop, organized by the School of simulated particles at 800 meters below the some ten years later, this legacy of support Engineering and Applied Sciences surface. for younger scientists at GFDL remains Program, the Atmospheric and Oceanic one of the key elements to the lab's Sciences Program, and GFDL, focused on continued success. environmental fluid dynamics. Workshop Commenting on the workshop, Palter said, The professional development sessions sessions ran from 9 a.m. to approximately "The Fluid Dynamics & the Global covered issues such as: strategies for 3 p.m. and covered such topics as: Environment Student-Postdoc meeting funding, proposal writing, negotiations, “Weather and Climate Simulations,” gave AOS and GFDL postdocs and and balancing work and family. The “Turbulence, Instabilities, and students a unique opportunity to interact agenda also included time for one-on-one Fundamentals,” and “Flows and Fluxes in with students and postdocs in Princeton's interaction between junior and senior Complex Geometries.” "As GFDL and the engineering departments. It is unusual to scientists as well as unstructured time for AOS program move towards thinking be at a workshop in which research ranges informal networking. “The Patullo about smaller spatial scales and coupling from the sub-millimeter scale of surface- Conference was a great way to meet a large with biological systems, we are finding the tension driven flows through flexible number of the female students and engineering community moving up to the membranes to the global scale of climate postdocs working in physical scales which we care about,” AOS Faculty modeling." ■ oceanography today. We had a lot of Member and GFDL Oceanographer Anand intense discussions, but also some fun Gnanadesikan said. kayaking in the alligator-filled river. I wish this sort of opportunity to talk and Among the speakers were AOS and CICS Conference learn about all the aspects of a scientific Researchers Rym Msadek, Joseph Kidston, career had been around when I was a Mehmet Ilicak, and Jaime Palter. During “Empowers” postdoc 15 years ago,” Legg added. the “Weather and Climate Simulations” session, Msadek presented predictability Women in Science The Pattullo Conference was held May 23- results based on GFDL coupled model 26, 2010 in Charleston, South Carolina. In simulations and discussed the challenge of In late May, AOS Lecturer and Research addition to the conference, MPOWIR’s providing reliable climate predictions Oceanographer Sonya Legg and CICS efforts include a website, mentor groups, a considering the lack of consensus Researchers Stephanie Downes, Rym blog, forums at major meetings, and the pertaining to the mechanism of decadal Msadek, and Jaime Palter participated in NASA MPOWIR Speaker Series. To learn climate variations. Kidston explored the the Pattullo Conference sponsored by more about MPOWIR, please visit: question of whether an increase in the eddy MPOWIR (Mentoring Physical http://www.mpowir.org/. ■ length scale can cause a poleward shift of Oceanography Women to Increase the jet streams during the “Turbulence, Retention.). The conference, named for Instabilities, and Fundamentals” session. June Pattullo, the first woman to receive a Rossi and Slater He presented an experiment with a Ph.D. in physical oceanography, is the barotropic model in which an increase in centerpiece of the MPOWIR program Honored at Service the length scale of a mid-latitude which provides mentoring to physical perturbation results in a poleward shift in oceanographers from late graduate school Recognition the acceleration of the zonal flow. Initial through their early careers and aims to investigations indicate that this behavior is reduce the barriers to career development Luncheon also valuable in both observational data for all junior scientists in the field, with a and the output of comprehensive general particular focus on improving the retention AOS Department Manager Laura Rossi circulation models (GCMs). of junior women. and Senior Earth System Modeler Rick Slater were honored for their dedication Ilicak kicked off the “Flow and Fluxes in In addition to research talks, professional during the annual Service Recognition Complex Domains” session with a development sessions, and round-table Luncheon on March 24th in Jadwin presentation on the challenges in resolving discussions, the program is unique in that it Gymnasium. Rossi and Slater were the overflows in GCMs. Noting the not only brings junior women and senior honored for their 25 years of service to the different processes that affect the amount scientists together to share experiences, University. of mixing in the overflows, such as shear advice, and concerns, but it raises instabilities and topographic features, he awareness of issues confronting junior Rossi joined the AOS Program in 1995, described how idealized and realistic women among the senior scientist after ten and a half years as Budget overflow simulations are performed with community. "The Pattullo conference was Officer/Grants Manager in the Chemistry different vertical mixing parameterizations. an excellent opportunity to network with Department. Under the broad direction of Ilicak also introduced a new approach to junior and senior scientists in the field of the Director, she plans, oversees and parameterize topographic features. Entitled physical oceanography, showcase the work directs the administrative and financial “Fronts in the oceans: Barrier, blenders, we do at Princeton and GFDL, and discuss affairs of the Program and the Cooperative and biogeochemical gateways,” Palter’s issues that women confront throughout Institute for Climate Science (CICS). With talk, also part of the “Flow and Fluxes in their career in science. Spending three the Director, she executes policy and Complex Domains” session, examined days in Charleston, South Carolina to learn strategic direction for the operation of AOS some of the work on exchange across more about each scientist's work in and CICS and participates in the short and ocean fronts and attempted to reconcile two her sub-specialty of physical long-term planning for the operations and opposing views on fronts: that they can be oceanography, as well as discussing some activities. She is responsible for ensuring physical barriers to exchange and that they of the 'soft-skills' required in scientific that the faculty, students and staff have the are critical gateways of biogeochemical endeavors, was time well spent, and great necessary assistance to carry out their property exchange. fun too,” said Palter. academic, research and administrative Borders, a humanitarian relief organization Klymak and Legg present a simple mixing duties. that provides lifesaving medical care scheme for models that resolve breaking around the world. The handicapped event internal waves based on the overturning During his twenty-five year tenure, Slater attracted a record number of walkers and scale of these breaking waves. The scheme has been affiliated only with the AOS runners from both GFDL and AOS and enhances mixing and viscosity in the Program. He works on model and code raised over one thousand dollars for the presence of breaking waves by assuming development for ocean and ocean- cause. that the overturning scale is equivalent to atmosphere general circulation models, the Ozmidov scale, which in turn is a particularly as it pertains to the carbon function of the dissipation and buoyancy cycle. He also provides support for stratification. The eddy viscosity and scientists and model analysis. diffusivity can then be calculated from the estimated dissipation using the widely-used AOS Director Jorge Sarmiento Osborn relation to yield a simple commended both Rossi and Slater, for their parameterization of the viscosity and “invaluable contributions to the Program diffusivity, in terms of the diagnosed over the years. Laura and Rick are overturning scales and the stratification. committed to excellence and our Program has long been the beneficiary of that The researchers expect that this scheme commitment. Their dedication to AOS and will be most useful for parameterizing the University extends way beyond their mixing in strong flows over topography, years of service.” Post-race cookout was a welcomed break. with particular application to internal tide generation and reflection problems. It may To commemorate their years of service, The winners of the 5K event were female also be useful for mean-flows over rough they were each presented with a certificate walker Karen Dreboty, male walker Jim topography such as might occur in the of recognition and received a chair bearing Byrne, female runner Rym Msadek, and Antarctic circumpolar current. an engraved University seal. Rossi and male runner Keith Dixon. Race Organizer Slater were two of the 342 University staff Rich Gudgel expressed thanks to the judges During their investigation, this method was members with a collective 6,550 years of Yanluan Lin, Tony Gordon, Ron Stouffer, compared to previous schemes for flow service recognized at the luncheon. ■ Aparna Radhakrishnan, and Tom Knutson over topography to show that, when eddy “without whom the race would not be diffusivity and viscosity are assumed to be possible.” A “courtyard” cookout proportional, it dissipates the correct GFDLEA Annual 5K immediately followed the race and was amount of energy, and that the dissipation enjoyed by all. ■ reported by the mixing scheme is Race consistent with energy losses in the model. A significant advantage of this scheme, On Tuesday, May 11th, 30 racers turned out according to the researchers, is that it has to participate in the GFDLEA Annual 5K AOS & CICS no tunable parameters, apart from the charity event benefiting Doctors without turbulent Prandtl number and flux Research in Action coefficient.

While the scheme is promising, Legg New Study Presents a cautions that the mixing scheme does have its limitations. “The major limitation of our Simple Mixing Scheme new mixing scheme is that the largest Alternative mixing events should be driven by breaking waves rather than unresolved Among research oceanographers, there is shear instabilities,” she noted. “The scheme considerable interest in how topography is most useful in process study simulations interacts with stratified flows to produce which resolve the largest scales of the internal waves and turbulence. With this wave breaking, but not the much smaller in mind, a fruitful collaboration between dissipation scales.” AOS Lecturer and CICS Researcher Sonya Legg and Jody Klymak at the University of As a next step, the researchers intend to use Victoria, has resulted in a simple this new scheme in simulations exploring alternative to previous approaches that mixing generated by the breaking of low parameterize the turbulence using a mode internal waves on reflection from steep topography. ■ universally large viscosity or use mixing 1st Place Winner, AOS Postdoctoral Research schemes that rely on Richardson-number Associate Rym Msadek criteria. The alternative is presented in a new study published in the April edition of Ocean Modelling.

Four Years Well Spent this place unique,” Farneti added. Delay the Shedding of Loop Current Eddies?” earned first place recognition, Farneti is now a Research Scientist in the Xu’s “The Origin of the Along-Shelf After completing a Ph.D. in Oceanography Earth System Physics Section of the Pressure Gradient in the Middle Atlantic at the Southampton Oceanography Centre, International Centre for Theoretical Bight,” secured second place, and Fujisaki UK, Riccardo Farneti joined the AOS Physics in Trieste, Italy. ■ was awarded third place for her Program in 2006 to work with Geoff presentation entitled, “Formation of Ice Vallis. Together, they developed an Bands by Wind.” intermediate complexity coupled model to study decadal and longer climate AOS & CICS News “I know that all three of them worked very, variability and other fundamental problems very hard on preparing for this

Congratulations to Graduate Student competition; I am extremely proud of Amanda O’Rourke who was selected to them,” said colleague and Research participate as a fellow in the 2010 Oceanographer Leo Oey. Geophysical Fluid Dynamics Program on “Swirling and Swimming in Turbulence” The competition was open to first author in the Woods Hole Oceanographic presenters who are graduate students or Institution (WHOI). She will be one of a postdocs not more than two years past their small group of competitively selected graduation. Entrants were judged on their graduate-student fellows to participate in research quality and presentation. the 10-week program this summer which **************************** commences with two weeks of Principal Welcome AOS Graduate Students Lectures delivered by Former AOS Associate Research Scholar Glenn Flierl (MIT), Riccardo Farneti The AOS Program extends a warm Antonello Provenzale (CNR Italy) and Jean-Luc Thifeault welcome to incoming graduate students: in climate dynamics. "Working with (U.Wisconsin). Lectures by staff and Kityan Choi and Wenyu Zhoa. Riccardo was always a pleasure, and he visitors on a wide range of GFD and accomplished a great deal of science while related topics will follow daily. he was here,” remarked CICS Associate

Director Geoff Vallis. “Not only was he **************************** The GFD Program promotes an exchange hardworking and bright, but he had a of ideas among researchers in the many positive attitude and a ready smile that kept distinct fields that share a common interest Visiting Research Collaborators things in perspective.” in the nonlinear dynamics of fluid flows in

oceanography, meteorology, geophysics, The AOS Program would like to Later, Riccardo joined the Climate Group astrophysics, applied mathematics, acknowledge the following people who at GFDL to work with the fine-resolution engineering and physics. Over its fifty one were recently appointed as Visiting GFDL Coupled Model CM2.4; he then year history, the Program has produced Research Collaborators, a new category of focused on the Southern Ocean climate numerous alumni, many whom are appointments which recognizes the sterling variability and change. “Riccardo made prominent scientists at universities efforts of GFDL staff members in helping some very important contributions while worldwide. The program will run from to advise graduate students: working with us in the Climate Group at June 21 to August 27, 2010. GFDL,” noted Tom Delworth, group leader Arlene Fiore, Gabe Vecchi, Mike of GFDL’s climate change, variability and **************************** Winton, Paul Ginoux, and Chip Levy prediction group. “In particular, his work using a high resolution global coupled model has provided important perspectives Researchers Sweep Outstanding **************************** on the role of small scale processes in the Young Scientist Competition at response of the climate system to changing IWMO-2010 Arrivals radiative forcing. In addition, Riccardo was an excellent colleague to work with, Hung-Fu Lu arrived in April to work with Congratulations to AOS Researchers Eda and we look forward to ongoing Leo Oey as a Visiting Associate Chang, Fanghua Xu. and Ayumi collaborations.” Professional Specialist. His research Fujisaki who placed first, second, and focuses on modeling the circulation in the third in the Outstanding Young Scientist "We spent four wonderful years in South China Sea using the Princeton Competition at the International Workshop Princeton and working at GFDL/AOS was Ocean Model. on Modeling of the Ocean (IWMO) a great experience. The coexistence of so Workshop in Norfolk Virginia on May many experts in different fields, and the Massimo Bollasina arrived in May and is 24th. possibility to do both fundamental and working with Yi Ming and V. Ramaswamy state-of-the-art climate modeling makes as a Postdoctoral Research Associate. His Chang’s presentation “Why Can Wind research focuses on understanding aerosol- research focuses on the sensitivity of induced regional circulation and isoprene emission changes to future hydroclimate changes. climate and air quality.

Lucas Harris arrived in May and is Visiting Student Thomas Flannaghan will working with Isaac Held, S.J. Lin and be arriving in September from Cambridge Morris Bender as a Postdoctoral Research to work with Stephan Fueglistaler. His Associate. His research focuses on the research focuses on Kelvin waves in the development of the regional-global two- tropical tropopause layer. way nesting capability within the High- Resolution Atmosphere Model (HiRam). Visiting Student Miguel Gomez-Escolar Viejo will be arriving in September from Meiyun Lin arrived in June and is working Complutense University, Madrid (Dept. with Arlene Fiore and Larry Horowitz as a Fisica de la Tierra II) to work with Stephan Postdoctoral Research Associate. Her Fueglistaler. He will be studying the time research focuses on multi-scale interactions series of temperature measurements between climate and air quality. in the tropical tropopause layer.

Patrick Lynett arrived in June and is Caroline Muller will be arriving in collaborating with S.J. Lin. He is a visiting October to work with Isaac Held as a faculty member from TAMU. His research Postdoctoral Research Associate. Her focuses on the nonlinear and coupled research focuses on a sensitivity study of interactions between wind, sea waves, tropical convection using a cloud resolving ocean, and storm surge during hurricanes. model.

K. Allison Smith arrived in July to work Visiting Student Maria Rugenstein will be with Jorge Sarmiento as a Postdoctoral arriving in October from ETH, Zurich to Research Associate. Her research focuses work with Isaac Held. Her research on the oceanography and ecology of focuses on questions related to the ocean’s suboxic regions in the ocean. uptake of heat in global warming simulations. Yohsuke Yamashita will be arriving in August to work with John Austin and Leo Departures Donner as a Visiting Postdoctoral Research Associate. His research focuses on the Riccardo Farneti – April 2010 effects of QBO on tropical and Earth System Physics Section of the extratropical stratosphere, dynamical and International Centre for Theoretical chemical analyses of lower stratospheric Physics in Trieste, Italy ozone variation associated with the solar cycle, and the effects on the troposphere. Dilip Ganguly – June 2010 AOS Program Pacific Northwest National Laboratory Princeton University Maarten Buijsman will be arriving in (PNNL), Richland, WA September to work with Sonya Legg as a Sayre Hall 300 Forrestal Road Postdoctoral Research Associate. His Ayumi Fujisaki – July 2010 research focuses on the numerical NOAA/Great Lakes Environmental Princeton, NJ 08540 investigation of non-linear internal wave Research Laboratory, Ann Arbor, MI generation and breaking in straits, in Phone: connection with a field program in the Joseph Kidston – July 2010 (609) 258-6047 Luzon Straits. University of New South Wales, Australia Fax: Thomas Frölicher will be arriving in Young-Gyu Park – August 2010 September to work with Jorge Sarmiento as (609) 258-2850 Returns to the Korean Ocean Research & a Postdoctoral Research Fellow. His Development Institute (KORDI) research focuses on the variability of the We’re on the Web! www.aos.princeton.edu coupled carbon cycle-climate system and numerical modeling with coupled atmosphere-ocean-biogeochemistry Earth Editor: Joanne Curcio System Models. Email: [email protected]

Jingqiu Mao will be arriving in September to work with Larry Horowitz as a Postdoctoral Research Associate. His