Data from Four Ice Ages, Used by Hansen
Things to Note
1. In graph (c), "Observations" (of global temperature) and "Calculated Temperature" match so well that there is no chance this is 400,000 years coincidence.
[Observed temperature is determined from the ratio of heavy hydrogen (deuterium) to normal hydrogen in antarctic snow. The extent of ice is based on sea level which is determined from sea level based on Red Sea sediment cores. Greenhouse gases (CO2 and methane) are measured from Antarctic Vostok ice cores.]