An Introduction to Seasonal Diagnostics Consortium Activites


Seasonal diagnostics consortium is an OGP/NOAA sponsored activity to understand seasonal predictability and to seek attribution for the observed seasonal climate anomalies on a near-real time basis. It is a well known fact that the observed seasonal climate anomalies are a blend of atmospheric response to the observed SST forcing, and a variability which is not related to SSTs (the so called atmospheric internal variability). The focus of this consortium is to understand the contribution of these two components to the observed seasonal climate anomalies. One way to separate out the influence of SSTs from the atmospheric internal variability is to have an ensemble of AGCM realizations forced with identical SSTs. Ensemble mean atmospheric anomaly then provides the information about the SST forced component of the observed seasonal means. However, because of different biases in the AGCMs, attribution of seasonal climate anomalies based on a simulations from a single AGCM alone, can lead to incorrect simulations. In this consortium activity, this potential problem is overcome by bringing together atmospheric simulations from many different models. An agreement between the atmospheric responses from different AGCMs adds to our confidence in the attribution aspect of the atmospheric climate anomalies.


Other goals of this consortium activity include: understanding the predictability aspects of seasonal mean atmospheric states; understanding the atmospheric response to anomalous SSTs; documenting atmospheric response to idealized SST forcing in different AGCM; impact of SST anomalies on the higher order moments of probability distribution function (PDF) of seasonal mean atmospheric states.


Following research institutions are currently participating in this consortium:


Climate Diagnostics Center (CDC), Boulder

International Research Institute for Climate Predictions (IRI)

Center for Ocean-Land-Atmosphere Studies (COLA)

Experimental Climate Prediction Center (ECPC), Scripps Institution of Oceanography

Geophysical Fluid Dynamics Laboratory (GFDL)

NASA Seasonal-to-Interannual Prediction Project (NSIPP)

Climate Prediction Center/National Centers for Environmental Predictions