Ship-based sea ice observation data (concentrations, ice thickness, topography and overlying snow cover) were collected from Middle Weddell Sea to Prydz Bay, Antarctic during the period of 4 to 17 Jan 2003. Antarctic ...Ship-based sea ice observation data (concentrations, ice thickness, topography and overlying snow cover) were collected from Middle Weddell Sea to Prydz Bay, Antarctic during the period of 4 to 17 Jan 2003. Antarctic ice chart of first week of Jan 2003 was derived from National Ice Center (NIC). The compared analysis of sea ice concentrations and thickness distributions were conducted though in situ data and NIC chart. Results from sea ice concentration-analysis indicated the presence of large-scale open water between 2000 and 4100 km along transit route resulted from sea ice drifting. We describe the existence of mostly smooth first-year sea ice in study region ranged between 30 and 120 cm. We also display the derived overlying snow coverage. Our results reveal the strong correspondence between ship-based observations and remotely sensed ice charts whatever in ice concentrations and ice thickness distributions.展开更多
Qinhuangdao City is located in the mid-latitude monsoon-affected region,and the timing of sea-ice coverage changes from year to year,making sea-ice forecasting difficult.In this paper,we propose a statistical model us...Qinhuangdao City is located in the mid-latitude monsoon-affected region,and the timing of sea-ice coverage changes from year to year,making sea-ice forecasting difficult.In this paper,we propose a statistical model using the 1980-2013 data collected at the Qinhuangdao observation station.The start date and the duration of ice coverage are fitted with four marginal distributions,from which the best-fitted,i.e.,the Weibull distribution,is selected to form a joint probability density function(PDF),built by the Gaussian copula method,for the two variables.With a given start date forecast by the Gray-Markov model(GMM),the joint PDF becomes a conditional probability model,which predicts that the duration of ice coverage is most likely 33 days at the Qinhuangdao observation station in 2014-2015.The predicted duration value is only two days less than the actual situation.The results prove that the new prediction model is feasible and effective to predict the period of ice coverage.The general sea-ice conditions that the sea ice would most likely form on December 8 and last for 80 days at the Qinhuangdao observation station could also be obtained from the joint PDF.The statistical model provides a useful tool to forecast ice conditions for planning and management of maritime activities.展开更多
文摘Ship-based sea ice observation data (concentrations, ice thickness, topography and overlying snow cover) were collected from Middle Weddell Sea to Prydz Bay, Antarctic during the period of 4 to 17 Jan 2003. Antarctic ice chart of first week of Jan 2003 was derived from National Ice Center (NIC). The compared analysis of sea ice concentrations and thickness distributions were conducted though in situ data and NIC chart. Results from sea ice concentration-analysis indicated the presence of large-scale open water between 2000 and 4100 km along transit route resulted from sea ice drifting. We describe the existence of mostly smooth first-year sea ice in study region ranged between 30 and 120 cm. We also display the derived overlying snow coverage. Our results reveal the strong correspondence between ship-based observations and remotely sensed ice charts whatever in ice concentrations and ice thickness distributions.
基金support of the National Natural Science Foundation of China (No. 51779236)the NSFC-Shandong Joint Fund Project (No. U1706226)the Ocean University of China under the support of 111 Project (No. B14028)
文摘Qinhuangdao City is located in the mid-latitude monsoon-affected region,and the timing of sea-ice coverage changes from year to year,making sea-ice forecasting difficult.In this paper,we propose a statistical model using the 1980-2013 data collected at the Qinhuangdao observation station.The start date and the duration of ice coverage are fitted with four marginal distributions,from which the best-fitted,i.e.,the Weibull distribution,is selected to form a joint probability density function(PDF),built by the Gaussian copula method,for the two variables.With a given start date forecast by the Gray-Markov model(GMM),the joint PDF becomes a conditional probability model,which predicts that the duration of ice coverage is most likely 33 days at the Qinhuangdao observation station in 2014-2015.The predicted duration value is only two days less than the actual situation.The results prove that the new prediction model is feasible and effective to predict the period of ice coverage.The general sea-ice conditions that the sea ice would most likely form on December 8 and last for 80 days at the Qinhuangdao observation station could also be obtained from the joint PDF.The statistical model provides a useful tool to forecast ice conditions for planning and management of maritime activities.
