1. GFDL Climate Model Status and Plans for Product Generation
Ants Leetmaa
Geophysical Fluid Dynamics Laboratory
Princeton, NJ 08542

2. Overview Status of Coupled Modeling IPCC plans
Upcoming updates/additions
Links to Other Modeling Activities
NCAR
Climate Process Teams
NOAA Seasonal Forecasting
Climate Change Science Program (CCSP) Deliverables

3. Status of Coupled Model Development - GFDL
Final decision on IPCC configuration within weeks
Represents significant improvement over old version (MCM – flux adjusted, e.g. almost specified SSTs)
Coupled performance comparable to uncoupled
9/1

4. IPCC Runs to be done in FY04
Climate of 20th Century Runs (ensembles)
“Committed climate run” extending 20th Century run to 2100 with constant concentrations at contemporary levels
Stabilization at 550 ppm from starting from 1. with SRES B1 scenario to 2100
Stabilization at 750 ppm from starting from 1. With SRES A2/A1B scenario to 2100
1000 year control run current forcings
1%/yr experiments to 2x & 4x
Some runs to 2300
Interactive carbon cycle and atmospheric chemistry assessments to be done separately.

5. Status of Further Model Developments
Terrestrial Carbon Cycle
Currently in development and evaluation
Complete offline and online testing 2nd Q FY04
Oceanic Ecosystems Modeling
Currently coded to run in GFDL ocean model
Terrestrial and oceanic carbon cycles coupled in 3rd Q FY04
Fully Interactive Atmospheric Chemistry – aerosols and gas phase testing starts in 4th Q FY04

6. GFDL - NCAR Collaborative Agreement
Purpose: accelerate the development of U.S. high-end climate modeling capabilities, and develop joint program to provide decision makers timely, reliable, well-documented model results, model-based analyses, assessments of variability and change. Main thrusts:
Identify and overcome common shortcomings on NCAR and GFDL models
Identify and explain, to the extent possible, the major differences between CCSM and the GFDL model with initial focus on differing climate sensitivities
establishment of community standards for model diagnostics packages and modeling infrastructure with DOE and NASA
Building community capacity for support of assessment and impact studies based on standard and specialized scenarios
Share data, model parameterizations, model results, and software and facilitate visits and exchange of staff

7. Participation in NOAA/NSF Climate Process Team Program (with NCAR and Others Modeling Groups)
Low-latitude Cloud Feedbacks on Climate Sensitivity: reduce uncertainty in climate projections arising from response of clouds to climate change
Gravity Current Entrainment: more accurate representations of overflows may lead to more reliable predictions of the ocean’s thermohaline circulation
Eddy-Mixed Layer Interactions: More accurate representations will improve simulations of temporal variations of the spatial structure of the ocean’s surface properties.

8. NOAA Seasonal Forecasting Activities
ENSO and Annual Cycle performance a factor in choice of model tuning
As part of NOAA Consortia coupled seasonal forecasting activities have begun
more recent
recent versions
Atmospheric tunings
Atmos/ocean tunings

9. Surface Temperature Anomaly for DJF 2002-2003
NOAA Seasonal Forecasting Activities
Surface Temperature Anomaly for DJF
Simulated by 5 AGCMs: CDC/NCAR; IRI; NCEP, NSIPP/NASA, GFDL
Forced by observed sea surface temperatures
Results from an OGP funded Seasonal Attribution & Forecasting Consortium
Another OGP Consortium looks at Ocean Data Assimilation for S/I Forecasting
GFDL
Observed Anomalies

10. CCSP Scientific Synthesis and Assessment Products
Products with major responsibilities
Climate projections for research and assessment based on emissions scenarios developed through the CCTP NOAA(L), NSF/DOE(S) (2-4yrs)
Climate Models and their uses and limitations, including sensitivity, feedbacks, and uncertainty analysis DOE(L),NOAA /NASA/NSF(S)) (within 2 years)
Heavy involvement in …
North American carbon budget and implications for the global carbon cycle DOE/NOAA/NASA/USDA/USGS
Aerosol properties and their impacts on climate NOAA/NASA
Scenario-based analysis of the climatological, environmental, resource, technological, and economic implications of different atmospheric concentrations of greenhouse gases - all

11. CCSP & CCTP: ..support climate change policy making ..case studies
Technological Scenario Case Study
What combination of technologies can be expected to provide energy consistent with different emissions rates
What are the range of plausible consequences … reflecting the technological options
Steps
Scenarios for technological performance with alternative profiles (CCTP end of 2004)
Modeled climate change for each scenario including dynamic carbon cycle and ..land use projections (mid-2005)
…impacts on soil moisture, streamflow, and vegetation (end of 2005/2006)
Final synthesis report (2007)