This dataset contains ice phenology for 56 lakes in the Northern Hemisphere from 1979 to 2019. The ice phenology was extracted from 3.125 km 37 GHz H-polarized evening brightness temperature data from Scanning Multi-channel Microwave Radiometer (SMMR), Special Sensor Microwave Image (SSM/I) and Special Sensor Microwave Imager/Sounder (SSMIS) data in the Calibrated Enhanced Resolution Brightness Temperature (CETB) dataset. According to the differences in the brightness temperature between lake ice and open water, a threshold algorithm based on Moving t test method was applied to determine the lake ice status for the pixels 6.25 km away from the lake shore, and the ice phenology dates for each lake were then extracted. For the overlapping lake ice phenology results extracted from multiple satellite, the results from the satellite with the highest utilization were prioritized. The lake ice phenology dataset provides valuable information about the changes in the lakes with seasonal ice cover in the past four decades.

Four ice dates (freeze-up start, freeze-up end, break-up start, and break-up end) and two durations (complete freezing duration and ice cover duration) are included. For Superior, Huron, Michigan, Erie, Ontario, Caspian Sea, and Ladoga, the percentage of annual maximum ice cover are also provided.The freeze-up start date represents the date when 5% of the lake surface was covered by ice, and the freeze-up end date is the date when 95% of the lake surface was covered by ice. Similarly, the break-up start date means the date when 5% of the lake surface was covered by water, and the break-up end date is the date when 95% of the lake surface was covered by water. The complete freezing duration represents the period from freeze-up end to break-up start, and the ice cover duration represents the period from freeze-up start to break-up end.When the lake did not have ice cover, the ice cover duration is recorded as 0; when the lake was not completely frozen, the complete freezing duration is recorded as 0. Empty cells in the ice cover duration or in the complete freezing duration mean that the extraction of date/duration failed.The latitude and longitude information refers to a central point of the studied lakes.