UPDATE: note to readers, Gray and Klotzbach are only discontinuing December forecasts for the season ahead due to limited predictive skill — for the time being. A main reason is the well-known “Spring barrier” in El Nino Southern Oscillation forecasts for the next year…
When is the last time you can recall any scientist suspending a highly visible public work because they decided it just didn’t have any predictive skill?
This is refreshing.
QUALITATIVE DISCUSSION OF ATLANTIC BASIN SEASONAL HURRICANE ACTIVITY FOR 2012
We are discontinuing our early December quantitative hurricane forecast for the next year and giving a more qualitative discussion of the factors which will determine next year’s Atlantic basin hurricane activity. Our early December Atlantic basin seasonal hurricane forecasts of the last 20 years have not shown real-time forecast skill even though the hindcast studies on which they were based had considerable skill. Reasons for this unexpected lack of skill are discussed.
Relationships between predictors and predictands which once seemed quite strong may fail to work in future years due to a phenomenon known as the ‘siege of time’. It is the failure of these once-promising relationships which requires the forecaster to demand as much understanding of linkages between predictors and predictands as possible.
We have developed a new way of assessing next year’s activity in terms of two primary physical parameters:
1. the strength of the Atlantic thermohaline circulation (THC)
2. the phase of ENSO
We strongly believe that the increases in atmospheric CO2 since the start of the 20th century have had little or no significant effect on Atlantic basin or global TC activity as extensively discussed in our many previous forecast write-ups and recently in Gray (2011). Global tropical cyclone activity has shown no significant trend over the past thirty years.
h/t to WUWT reader JohnD