In this paper, based on the correlation between meteorological factors and sea ice area from 1958 to 2015, we study sea ice area change and its driving factors. The results show that the maximum and average of sea ice area showed a downward trend, with annual change rates of −0.33±0.18% and −0.51±0.16%, respectively. The whole period can be divided into slight growth (1958–1980), significant decline (1980–1995) and moderate growth (1995–2015). The temperature change rate during the ice melting period is much larger than the freezing ice period. Based on the relationship between sea ice area and temperature, this paper studies the change of sea ice area and the driving effect of temperature.
The cryosphere is highly sensitive to climate change. This has been confirmed by the reduction of polar ice sheets and the shrinkage of mountain glaciers in recent years (Qin Dahe, 2014). As one of the important components of the cryosphere, sea ice will also be a clear response to climate change (Rui Ruibo, 2008; Liu et al., 2013). For seasonal sea ice (Barron Sea (Årthun et al., 2012), Baltic Sea (Karpechko, 2015), the Sea of Khoik (Paik, 2017), and the Bohai, etc., their responses to climate change not only reflects the interaction between sea and air, but also the indication of coastal climate change, and also involves sea ice in coastal areas and relates to disaster prevention and mitigation. Bohai Sea region is a critical economic zone in China. Winter sea ice poses a serious threat to human economic activities such as offshore oil exploration, marine transportation, aquaculture, and offshore engineering construction, especially in severe ice conditions. Closely monitoring the sea ice conditions and their variability in this region is impotant for ice disaster prevention and climate change studies (Ji, 2011; Sun, 2012; Xu, 2015),
Accurately grasping the characteristics of ice changes in the seasonal sea ice of the Bohai Sea is a key link to study its response to global climate change, indications of coastal climate change, and strategies for assessing sea ice hazard risk. At that time, in order to express the degree of ice in the entire Bohai Sea area, the ice level index was established, and it was used as a reference for analyzing the changes of large-scale ice conditions by point and area (Ding, 1999). And remote sensing technology has become the main means of sea ice monitoring. Many scholars use remote sensing data to invert sea ice area (Comiso, 2008; Notz, 2016), making it possible to obtain large-scale sea ice area data that was difficult to obtain in the past. However, remote sensing data, especially optical satellite images, are easily affected by the cloud, and the available images are relatively low. Therefore, the use of remote sensing data to invert daily sea ice area has many problems such as missing data and the time series is not long enough (Cavalieri, 1999). Yan, 2017).