The beginning and end of a glacial period are clearly times of global climate change, but there are also periods of abrupt change in climate patterns within those periods. (sciencedaily.com)
In fact, here's an article discussing the process that scientists went through in the 20th century as they came to grips with the evidence of abrupt climate change. (theoildrum.com)
Worse, it has one of the most awkward abrupt endings of a major release in recent memory. (awardscampaign.com)