The earth’s climate was much warmer millions of years ago

There is so much alarm because of Global Climate Change. Therefore, I wanted to see if the earth was ever as warm or warmer than it is now. I found that the earth has been much warmer than it is today millions of years ago.

Following, please find a chart showing the earth’s climate for the last 65 million years, from an online article by John Baez called, Temperature:

Temperature over the last 65 million years

The description that goes with this chart is as follows:

This shows the Earth’s temperature since the extinction of the dinosaurs about 65 million years ago – the end of the Mesozoic and beginning of the Cenozoic. At first the Earth warmed up, reaching its warmest 50 million years ago: the “Eocene Optimum”. The spike before that labelled “PETM” is a fascinating event called the Paleocene-Eocene Thermal Maximum. At the end of the Eocene the Earth cooled rapidly and the Antarctic acquired year-round ice. After a warming spell near the end of the Oligocene, further cooling and an increasingly jittery climate led ultimately to the current age of rapid glacial cycles – “ice ages”.
This chart is taken from here:

Robert Rohde, 65 million years of climate change, for Global Warming Art.