Climate change has been occurring ever since the earth’s formation 4.5 billion years ago. Long before any industrial activity, the earth’s average temperature increased and decreased for centuries. The Medieval Warm Period (c. 950–1250) and earlier periods may very well have been as warm as or warmer than the present. […]  Natural variations in climate such as fluctuations in solar activity, volcanic activity, or ocean oscillations like El Niño have all contributed to global warming and global cooling […] he idea that the science of climate change is ‘settled’ is an absurdity, contrary to the very spirit of scientific enquiry. […] The Earth has been recovering from the Little Ice Age for a couple of centuries and recovering from a real ice age for thousands of years; it is simply impossible to know whether any observed current warming is a continuation of this natural trend or represents some new man-made phenomenon.