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). 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. 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. The first numerical simulation of the world ocean. 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. 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). The development of a state-of-art hurricane model and its transfer to operations in the NOAA National Weather Service and the Navy. Scientific divisions 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 divisions (listed alphabetically below), in addition to a large group of scientific programmers known as the Modeling Systems Division, as well as a large computer support group. Atmospheric Physics Current head: Dr. Venkatachalam Ramaswamy This divisions goal is to employ numerical models and observations of the Earth System to characterize and quantify atmospheric physical processes, particularly those involving greenhouse gases, aerosols, water vapor, and clouds, and their roles in atmospheric general circulation, weather and climate. Biogeochemistry, Atmospheric Chemistry, and Ecosystems Current head: Dr. John P. Dunne This divisions goal is to develop and use the GFDL’s earth system models to create a