Over the past 40 years, the Arctic Ocean has predominantly experienced warming. This warming has led to a significant reduction in sea ice extent and thickness, particularly during the summer months. The region has been affected by climate change, which has caused temperatures to rise at a rate much faster than the global average. As a result, the correct answer to your question is that the Arctic Ocean has become warm.
While there can be variations in ice extent from year to year, the long-term trend shows a decline in overall ice cover rather than an increase.