Read here. Over recent decades, it has been noted that Hudson Bay sea ice has been breaking up earlier in the summer season. These are anecdotal recollections/observations that scientists decided to investigate, using an array of advanced technology.
This new peer-reviewed research regarding the Hudson Bay sea ice issue indicates there is actually no trend of earlier sea ice breakup in the area. The data analysis does show, though, a one-time shift to an earlier breakup date during late 1980's, but no trend prior or post to that event that can be attributed to AGW causes.
"Working with passive microwave data obtained from the Scanning Multichannel Microwave Radiometer onboard the Nimbus 7 satellite, plus three Special Sensor Microwave/Imager instruments onboard Defense Meteorological Satellite Program satellites -- as well as Canadian Ice Service sea-ice charts that are considered to be "more accurate than passive microwave data for estimates of ice concentration, particularly in the presence of surface melt,".....the two researchers from the British Antarctic Survey found that "there has clearly not been a continuous trend in the [time of sea-ice breakup] data, and the change is best described by a step to 12 days earlier breakup occurring between 1988 and 1989, with no significant trend before or after this date." ....."Clearly, the science pertaining to this matter is still not wholly settled; and, therefore, humanity cannot yet be blamed for what the world's climate alarmists consider to be the "bad behavior" of western Hudson Bay in regard to the temporal advancement of the yearly date of sea-ice breakup caused by the one-time adjustment in this parameter that occurred in the late 1980s." [Scott, J.B.T. and Marshall, G.J. 2010.]
Other peer-reviewed postings.