The parameters that drive the 2013 and 2014 global temperature forecast are the same as the other parameters, but with an included sheet titled "Forecast" that allows you to select the predominant ENSO phase for the forecast years. ENSO has a significant impact on year-to-year variability and is super-imposed upon the long-term warming trend from human activities. The graph above shows the global temperature estimate from the GISS record in black, the linear trend of the GISS data in gray, and the forecast in red. The uncertainty range of the forecast is derived from the maximum error of the model to the GISS record, and as such is based heavily on the parameters set to drive the model.
Click here to change Parameters by editing the Google Document controlling these charts. Refresh this page once the the parameters are changed.