That’s an interesting chart. It looks like the Earth’s temperatures meander down from the baseline and then suddenly, and with some regularity, sharply spike up, relatively quickly drop to the baseline, and then begin the cycle again. Am I correct? What’s causing this cycle?
Two observations from the chart:
One: The warm periods are a lot more narrow than generally assumed.
Two: The mean temperature should be assumed 10 degrees below current.
The global climate change hoaxers should concentrate on finding what happened 1 to 3 million years ago that set off the ice ages. My guess is the Gulf Stream started to flow or something kicked off the El Ninos.