Geophysical Fluid Dynamics Laboratory

The Geophysical Fluid Dynamics Laboratory (GFDL) is a laboratory in the National Oceanic and Atmospheric Administration (NOAA) Office of Oceanic and Atmospheric Research (OAR). The current director is Dr. Venkatachalam Ramaswamy. It is one of seven NOAA Research Laboratories (RLs).^[1]

GFDL is engaged in comprehensive long lead-time research to expand the scientific understanding of the physical processes that govern the behavior of the atmosphere and the oceans as complex fluid systems. These systems can then be modeled mathematically and their phenomenology can be studied by computer simulation methods.

GFDL's accomplishments include the development of the first climate models to study global warming, the first comprehensive ocean prediction codes, and the first dynamical models with significant skill in hurricane track and intensity predictions. Much current research within the laboratory is focused around the development of Earth System Models for assessment of natural and human-induced climate change.

Major accomplishments

• The first global numerical simulations of the atmosphere — defining the basic structure of the numerical weather prediction and climate models that are still in use today throughout the world.^[2]
• The first numerical simulation of the world ocean.^[2]
• The initial definition and further elaborations of many of the central issues in global warming research, including water vapor feedback, polar amplification of temperature change, summer mid-continental dryness and cloud feedback.^[2]
• The first coupled atmosphere-ocean climate models and the first simulations of global warming using these models (including the above feedback processes and the potential weakening of the Atlantic overturning circulation).^[2]
• The development of a state-of-art hurricane model and its transfer to operations in the NOAA National Weather Service and the Navy.^[2]

Scientific groups

The GFDL has a diverse community of about 300 researchers, collaborators and staff, with many from Britain, India, China, Japan, France, etc. The laboratory is currently organized into several scientific groups (listed alphabetically below) as well as a large computer support group.

Atmospheric physics, chemistry and climate

Current head: Dr. Hiram Levy II

This group focuses on processes that affect the vertical structure of the atmosphere, such as convection and radiation. A particular focus is the role of aerosols in climate, both through direct effects on the radiative balance, and indirect effects on cloud physics.

Climate and ecosystems

Current head: Ron Stouffer

This group focuses on interactions between the physical climate and biogeochemical systems, both in the land and ocean. Development of GFDL's Earth System Model is centered in this group.

Climate diagnostics

Current head: Dr. Ngar-Chung (Gabriel) Lau

This group focuses on comparing models with observations, developing observational datasets that can be compared with models, and using models to isolate key processes that regulate interannual variability in the ocean and atmosphere.

Climate change, variability and prediction

Current head: Dr. Tom Delworth

The largest group in the lab centers on the development of numerical models for predictions and projections of climate on seasonal-to-centennial time scales. Major projects include the development of El Nino predictions for seasonal forecasting, and the production of IPCC-class climate models.

Oceans and climate

Current head: Dr. Robert Hallberg

This group focuses on the role played by the oceans in the large-scale climate system, and on developing state-of-the-art numerical codes to simulate the ocean.

Weather and atmospheric dynamics

Current head: Dr. Isaac Held

This group focuses on the dynamics of the atmosphere, with particular emphasis on the interactions between waves and turbulence and the large-scale flow. Development of GFDL's hurricane model is supported from this group.

Facilities

The GFDL is located at Princeton University's Forrestal Campus in Princeton, NJ.

Since March 2011, the GFDL no longer possesses an on-site supercomputer. They instead utilize a massively parallel Cray supercomputer with over 30,000 processor cores which is currently located at Oak Ridge National Laboratory in Oak Ridge, Tennessee. This contrasts from their previous systems architecture, which consisted of eight Silicon Graphics Altix computers, each housing 1024 processor cores.^[3] Hardware updates occur on average, every 18 months.

The GFDL has been utilizing High Performance Computing Systems for Numerical Modeling since the 1950s.

Alumni

• Joseph Smagorinsky: GFDL's first director
• Jerry Mahlman: GFDL's second director
• Ants Leetmaa: GFDL's third director
• Kirk Bryan (American Oceanographer)
• Syukoro Manabe
• Yoshio Kurihara

See also

• Modular Ocean Model
• GFDL CM2.X

References

External links

• National Oceanic & Atmospheric Administration
• NOAA's Office of Oceanic and Atmospheric Research
• Geophysical Fluid Dynamics Laboratory
• NOAA GFDL ranking among the Top 500 Supercomputer Sites
• http://www.ncrc.gov/