The National Marine Environmental Forecasting Center issued the first sea ice blue alert this winter for Liaodong Bay on Jan 16, warning of potential threats to offshore oil drilling, water course safety and fishery industries.

The latest satellite images showed the area of ice in Liaodong Bay reached 16,120 sq km on Jan 16, accounting for 53 percent of the bay’s total area with the ice up to 40 cm thick.

The center predicted the growth of ice in the bay will slow over the next three days.

China has experienced the coldest December in 28 years, with an average temperature at –3.8 C. Hulunbuir League in the Inner Mongolia autonomous region even saw a record low of –46 C on Jan 7.

The sea ice alerts are classified into four levels: red, orange, yellow and blue.

The blue alert in Liaodong Bay means the ice thickness is reaching 30 cm and the floating sea ices' outer margin has grown to 130 km from the bay's shore.