Historical clue formulations

• Cool-down stretches? — 2024-05-03
• Periods with the largest glaciers — 2019-07-15
• Subjects in paleoclimatology — 2019-03-16
• Periods in contrast to global warming — 2007-05-06
• Cooling-off periods — 2005-11-25
• No mere cold snaps — 2001-08-03
• Cooling-off periods — 2001-02-17
• Deep freezes, so to speak — 1999-09-21