Analysis Of Temporal Variation Characteristics Of Sea Ice Movement In The Canada Sea Basin From August 2018 To February 2019

Arctic sea ice is the most active and volatile component of the Arctic region.With the dramatic changes in the Arctic climate system,sea temperatures are rising and sea ice is decreasing.The extent and thickness of Arctic sea ice has been decreasing since 1979.Although the immediate cause of the decline in Arctic sea ice is the rapid change in the energy process in the Arctic,changes in albedo at the air-sea ice interface due to the redistribution of sea ice caused by sea ice movement feed back into the energy budget,and wind forces accelerate the rapid outflow of sea ice out of the Arctic Ocean.Therefore,the process of sea ice movement plays a very important role in the change of sea ice in the Arctic Ocean.China is an important stakeholder in Arctic affairs.Although the change of Arctic sea ice has a huge impact on China's climate,it still plays a positive role in China's development.For example,the opening of the Arctic sea route has significant transportation and military value to China.Therefore,it is of great significance to study the characteristics of Arctic sea ice movement.In this study,the temporal variation characteristics of sea ice movement in the Canada Basin were analyzed based on the field observation data of drifting buoys for small time scale processes.Firstly,VB programming means is used to design the program of data batch download and the design of data processing software.On this premise,the variation characteristics of sea ice movement in a short time and in a small range were studied,as well as the influence of wind field on sea ice movement.The correlation analysis between sea ice movement speed and wind field was conducted by combining the measured data with remote sensing data.The study divided the measured data of buoys into 13 periods from August 16,2018 to February 26,2019.The results show that the sea ice movement in the Canada Basin has distinct characteristics of change with time.The speed of sea ice in a time period can reflect the intensity of the change of direction of motion to a certain extent,and the direction of motion is stable in a time period when the speed of sea ice is high.When the speed of sea ice movement is small,the direction of sea ice movement changes dramatically,which is manifested in the increase of inflection points in the movement trajectory.In the case of a single floe,the speed of motion is high in summer and low in winter.After entering the winter,the floating ice experienced a fluctuating decline process for two months,and the decline rate was about0.24cm/s per day.According to the absolute value ? of the Angle difference between the direction of sea ice motion and the wind direction,the sea ice motion can be divided into three types: class I motion(0°???45°),class II motion(45° < ? < 135°)and class III motion(135°?? < 180°).The sensitivity of the direction of sea ice movement to wind direction can be reflected by the frequency of class I movement.The results show that the sensitivity of sea ice direction to wind direction can reflect the characteristics of sea ice movement to a certain extent.There is a significant positive correlation between sea ice velocity and wind speed both in the overall process and in different time periods.When there is a strong correlation between the velocity value and the wind speed value of a single floating ice,the direction of the wind direction has a strong guiding effect with the direction of the ice movement,and the direction of the ice movement is highly sensitive to the wind direction.In addition,according to the value of wind force coefficient of convective ice,the average value of wind force coefficient of floating ice in a period of time shows that 0.02 proposed by Nansen's law is the dividing line of seasonal characteristics of movement of a single floating ice.When the average wind coefficient of floating ice is greater than 0.02,the movement characteristics of floating ice in this period are summer characteristics.When the average wind coefficient of floating ice is less than 0.02,the movement characteristics of floating ice in this period of time show winter characteristics.