A SEASONAL OUTLOOK FOR THE OPENING DATE OF NAVIGATION TO PRUDHOE BAY, 1979-2000

摘要

This paper examines an all-subsets regression approach for forecasting the first date of ice- free navigation to Prudhoe Bay. The opening navigation date is derived from National Ice Center ice charts, and the potential predictors include sea-ice, atmospheric, and teleconnection data. Results indicate that the opening date for navigation to Prudhoe Bay has become earlier over the 1979-2000 study period, and that the opening date can be predicted using the January multiyear ice (MYI) Gradient (MYIG1) and the April freezing degree-day (FDD) accumulations (FDD4). Earlier opening dates occur when the April FDD accumulations are reduced and the January MYIG is negative, indicative of warmer April temperatures and reduced ice volume in the Beaufort Sea, respectively. The mean absolute error of the model is 3.71 days.