He provides a good overview of the geological, climatic and in turn species and life changes on Earth for the past millions of years. He concludes the following:
His simple conclusion that in the past Climate has been changing, hence, the present change is not to be worried. However, the issue at this point in time is "Is the present Climate Change induced by humans? and how does it effect the human and other life in the coming decades and centuries."
On all scales of observation and measurement, sea level and climate are not constant. Change is normal and is driven by a large num-ber of natural forces. Change can be slow or very fast. However, we see political slogans such as Stop Climate Change or government publications such as Living with Climate Change, demonstrating that both the community and government believe that climate variability and change are not normal. By using the past as the key to the present, we are facing the next inevitable glaciation, yet the climate, economic, political and social models of today assess the impact of a very slight warming and do not evaluate the higher risk of yet another glaciation. Geology, archaeology and history show that during glaciation, famine, war, depopulation and extinction are the norm.
If possible, can we do something about it?