Using a skillful statistical model to predict September sea ice covering Arctic shipping routes

The rapid decrease in Arctic sea ice cover and thickness not only has a linkage with extreme weather in the midlatitudes but also brings more opportunities for Arctic shipping routes and polar resource exploration,both of which motivate us to further understand causes of sea-ice variations and to obtain more accurate estimates of seaice cover in the future.Here,a novel data-driven method,the causal effect networks algorithm,is applied to identify the direct precursors of September sea-ice extent covering the Northern Sea Route and Transpolar Sea Route at different lead times so that statistical models can be constructed for sea-ice prediction.The whole study area was also divided into two parts:the northern region covered by multiyear ice and the southern region covered by seasonal ice.The forecast models of September sea-ice extent in the whole study area(TSIE)and southern region(SSIE)at lead times of 1–4 months can explain over 65%and 79%of the variances,respectively,but the forecast skill of sea-ice extent in the northern region(NSIE)is limited at a lead time of 1 month.At lead times of 1–4 months,local sea-ice concentration and sea-ice thickness have a larger influence on September TSIE and SSIE than other teleconnection factors.When the lead time is more than 4 months,the surface meridional wind anomaly from northern Europe in the preceding autumn or early winter is dominant for September TSIE variations but is comparable to thermodynamic factors for NSIE and SSIE.We suggest that this study provides a complementary approach for predicting regional sea ice and is helpful in evaluating and improving climate models.

Scale and scope of maritime cargoes through the Arctic Passages

This paper investigates the sources of goods being shipped through the Arctic passages, and trade generated in the Arc- tic, including oil and gas exploitation. Furthermore, it assesses the present situation for maritime cargo shipped from the Far East to Northwestern Europe and North America. Two main types of cargo are predicted to pass through the Arctic passages in the future. First, about 10 million t of liquefied natural gas will be delivered from Russia and the Nordic Arctic to the Far East by 2030. Second, there will be two-way trade flow of containerized cargo from the Far East to Europe and the United States through the North- east, Central and Northwest Passages. This will relieve pressure on present routes from the Far East to Northwestern Europe and North America. If Arctic navigation is technically possible in all seasons and shipping costs fall to those of ordinary ships, then assuming an equal share of shipping volume with the traditional canal routes, the maximum container freight passing through the Arctic passages by 2030 will be approximately 17.43 million TEUs （Twenty-foot Equivalent Units） per year, which is 85% of the volume transported on traditional canal routes in 2011. We conclude that there will be large-scale gas transportation through the Northeast Passage in the near future, and transit shipping across the Arctic will focus more on container transportation. The differences in shipping costs between Arctic routes and traditional canal routes are also compared.