Despite that Al Gore declared this topic closed, there is much information that can be debated, with proof of global warming or cooling based on facts and science. Consider:
- We are living in an abnormally cool period since the earth’s average surface temperature for most of its history averaged 22 Celsius compared to the present 14 C.
- Ice ages occur at approximately 250-million-year intervals.
- Fossil evidence suggest that during the Mesozoic Era (230 to 50 million years ago) the earth was 10 C to 15 C warmer than today.
- One million years ago the current ice-age (Pleistocene) began.
- Glacial stages last more than 100,000 years and are interrupted by interglacial stages that last about 10,000 years.
- We are now living in an abnormally warm period compared to the earth’s average temperature for the last one million years (during which glaciation has prevailed).
- The current interglacial period has been subject to climatic changes on a smaller scale than the change from glacial to interglacial but still large enough to disrupt civilizations.