Program in Atmospheric and Oceanic Sciences

Director of the Program in Atmospheric and Oceanic Sciences and Graduate Studies

Jorge L. Sarmiento, 306 Sayre Hall

Director of the Geophysical Fluid Dynamics Laboratory (GFDL)

Ants Leetmaa, 220 GFDL

A complete faculty listing is provided under the Department of Geosciences.

 

The Program in Atmospheric and Oceanic Sciences (AOS) offers graduate study under the sponsorship of the Department of Geosciences. An understanding of the complex behavior of the atmosphere and oceans requires a balanced effort in theoretical analysis, numerical modeling, laboratory experiments, and analysis of observations.

The AOS program benefits from the research capabilities of the Geophysical Fluid Dynamics Laboratory (GFDL) of the National Oceanic and Atmospheric Administration, which is located on the Forrestal campus. GFDL has a major in-house supercomputer facility to which students have direct access for their research. Many GFDL scientists are active in the AOS program as lecturers with the rank of assistant through full professor. The geosciences department, with its activities in physical and chemical oceanography, paleoceanography, and paleoclimatology, collaborates with GFDL in providing an academic program of courses and seminars.

Admission

A candidate for admission should apply to the program, and upon acceptance is placed as a program student in the Department of Geosciences. Preference is given to applicants with strong preparation in the physical sciences, such as applied mathematics, chemistry, engineering science, fluid dynamics, geophysics, and physics. Previous experience in meteorology or oceanography may be helpful, but does not weigh as heavily in the admission decision as the quality of the basic preparation. Applicants are required to take the aptitude and advanced tests of the Graduate Record Examination.

Financial Aid

Students in the program are normally appointed as assistants in research to a staff member, thus affording them both full financial support and early supervised research experience. The appointment carries with it a stipend, summer salary, and payment of tuition. The specific amounts are included in the admission offer that is made to successful candidates and is adjusted annually.

Plan of Study

Upon entering the program, the student is advised by the graduate work committee until he or she selects an adviser from the program staff. The plan of study is flexible and is tailored to the needs of the individual, but during the first two years normally concentrates on course work and independent preparation for the general examination.

Research projects in the following areas are emphasized: climate dynamics, the planetary-scale circulation of the atmosphere and the ocean, and interactions between the atmosphere and the ocean; hurricanes, fronts, tornadoes, and other smaller-scale phenomena in the atmosphere; turbulence and thermal convection; waves in rotating, stratified fluids; numerical weather prediction; planetary atmospheres; modeling of oceanic and atmospheric chemistry; paleoclimatology; and atmospheric radiation and cloud processes. The program is also a member of the Princeton Environmental Institute (PEI), which provides an opportunity for students to undertake multidisciplinary environmental research.

General Examination

The general examination, which is taken by the end of the second year, probes the student’s knowledge of basic geophysical fluid dynamics and certain specialty areas through written examinations and a research seminar presentation. The purpose of the research seminar is to demonstrate the student’s ability to work independently and analyze a research problem.

Students qualify for the award of the Master of Arts (M.A.) degree by successfully completing all course work and passing the written portion of the general examination.

Dissertation and Final Public Oral Examination

The dissertation must show that a candidate has technical mastery in the chosen field and is capable of independent research. The dissertation is expected to be a positive contribution that is of publishable quality. The final public oral examination is a broad examination in the field of study as well as a defense of the dissertation.

Courses

AOS 527 Atmospheric Radiative Transfer (also GEO 527)

V. Ramaswamy

The structure and composition of terrestrial atmospheres. The fundamental aspects of electromagnetic radiation, absorption and emission by atmospheric gases, optical extinction by particles, the roles of atmospheric species in the Earth’s radiative energy balance, the perturbation of climate due to natural and anthropogenic causes, and satellite observations of climate systems are also studied.

AOS 537 Atmospheric Chemistry (also GEO 537)

Hiram Levy II

Natural gas phase and heterogeneous chemistry in the troposphere and the stratosphere, with a focus on elementary chemical kinetics; photolysis processes; oxygen, hydrogen, and nitrogen chemistry; transport of atmospheric trace species; tropospheric hydrocarbon chemistry and stratospheric halogen chemistry; stratospheric ozone destruction; local and regional air pollution; and chemistry-climate interactions are studied.

AOS 547 Atmospheric Thermodynamics and Convection (also GEO 547)

Leo Donner

The thermodynamics of water-air systems. The course gives an overview of atmospheric energy sources and sinks. Planetary boundary layers, closure theories for atmospheric turbulence, cumulus convection, interactions between cumulus convection and large-scale atmospheric flows, cloud convection-radiation interactions and their role in the climate system, and parameterization of boundary layers and convection in atmospheric general circulation models are also studied.

AOS 571 Introduction to Geophysical Fluid Dynamics

Steve Garner

Physical principles fundamental to the theoretical, observational, and experimental study of the atmosphere and oceans; the equations of motion for rotating fluids; hydrostatic and Boussinesq approximations; circulation theorem; conservation of potential vorticity; scale analysis, geostrophic wind, thermal wind, and the quasigeostrophic system; and geophysical boundary layers are studied.

AOS 572 Atmospheric and Oceanic Wave Dynamics

Isidoro Orlanski

Observational evidence of atmospheric and oceanic waves; laboratory simulation. Surface and internal gravity waves; dispersion characteristics; kinetic energy spectrum; critical layer; forced resonance; and instabilities. Planetary waves: scale analysis; physical description of planetary wave propagation; reflections; normal modes in a closed basin. Large-scale baroclinic and barotropic instabilities, Eady and Charney models for baroclinic instability, and energy transfer.

AOS 573 Physical Oceanography (also GEO 573)

S. George H. Philander

Response of the ocean to transient and steady winds and buoyancy forcing. A hierarchy of models from simple analytical to realistic numerical models is used to study the role of waves, convection, instabilities, and other physical processes in the circulation of oceans.

AOS 575 Numerical Prediction of the Atmosphere and Ocean

Staff

Barotropic and multilevel dynamic models; coordinate systems and boundary conditions; finite difference equations and their energetics; spectral methods; water vapor and its condensation processes; orography, cumulus convection, subgrid-scale transfer, and boundary-layer processes; meteorological and oceanographic data assimilation; dynamic initialization; verification and predictability; and probabilistic forecasts.

AOS 576 Current Topics in Dynamic Meteorology

Isaac M. Held

An introduction to topics of current interest in the dynamics of large-scale atmospheric flow. Possible topics include wave-mean flow interaction and nonacceleration theorems, critical levels, quasigeostrophic instabilities, topographically and thermally forced stationary waves, theories for stratospheric sudden warmings and the quasi-biennial oscillation of the equatorial stratosphere, and quasi-geostrophic turbulence.

AOS 577 Weather and Climate Dynamics (also GEO 577)

Ngar-Cheung Lau

An examination of various components of the Earth’s climate system. Emphasis is on the role of radiative processes, climate feedbacks and sensitivity, and the nature of energy and water balances. The dynamics and physical interpretation of principal tropospheric circulation systems, including stationary and transient phenomena observed in middle and low latitudes, are studied. Phenomena of topical interest, such as El Niño, seasonal climate anomalies, and natural and anthropogenic climate changes, are also reviewed.

AOS 578 Chemical Oceanography (also GEO 578)

Jorge L. Sarmiento

The chemical composition of the oceans and the nature of the physical and chemical processes governing this composition in the past and the present. The cycles of major and minor oceanic constituents, including interactions with the biosphere, and at the ocean-atmosphere and ocean-sediment interfaces.

AOS 580 Special Topics

Staff

Topics covered in recent years have included baroclinic instability theory, convection, paleoclimatology, atmospheric radiative transfer, isotope geochemistry, El Niño and related phenomena, tropospheric chemistry, and ocean dynamics in the Southern Hemisphere.

Undergraduate Course of Interest

Geosciences

425 Introduction to Physical Oceanography