What do ice core records reveal about Earth’s climate?
If we take a journey back through Earth’s climatic history, we find that between about 1350 and 1850 there were two distinct cold periods, referred to as the Little Ice Age, when temperatures were about 1°C (1.8°F) lower than today’s. [4] Rivers and lakes inthe northern hemisphere would regularly freeze over during winter, and indeed the Thames in London, over a period of about 400 years, would freeze over on average every twenty-five years or so. The freezing of the river may have been assisted, however, by the slower-moving water due to old London Bridge in situ at the time. If we go back further, from about 1000 AD to about 1300, we arrive at a period known as the Medieval Warm Period. Temperatures during this time were warmer than they had been for thousands of years before that, but similar to now.[5] Further back still, from between 10,000 and 15,000 years ago, we arrive at the end of the last Ice Age or glacial period. The period from then, which we are still in, is called the [
