There was a period during the last ice age when temperatures in the Northern Hemisphere went on a rollercoaster ride,plummeting and then rising again every 1500 years or so. Those abrupt climate changes wreaked havoc on ecosystems, but their cause has been something of a mystery. original evidence published this week in the leading journal Science shows for the first time that the ocean's overturning circulation slowed during every one of those temperature plunges - at times nearly stopping.
Source: phys.org