Global warming is likely to disrupt a natural cycle of ice ages and help delay the onset of the next big freeze until about 100,000 years from now, scientists say.

In the past million years, the world has had about 10 ice ages before swinging back to warmer conditions like the present. In the last freeze, which ended 12,000 years ago, ice sheets blanketed what is now Canada, northern Europe and Siberia. In a new explanation for the long-lasting plunges…