And, if we were to find a physicist who said climate change DOES exists, the opposition would say; "That's not a climatologist - his/her opinion does not matter."
Climate change does exist; it has existed since the earth cooled enough to have a climate. If you wish to argue there is no such thing as climate change then explain the Pleistocene, the Cambrian period and generally Geochronology of the earth is a long running example of climate change.
Britannica said:
The Cambrian world differed greatly from that of the present, but it was also quite different from the preceding
Proterozoic Eon (2.5 billion to 541 million years ago) in terms of climate, geography, and life. Average global temperatures during much of the Neoproterozoic Era (1 billion to 541 million years ago) were cooler (around 12 °C [54 °F]) than the average global temperatures (around 14 °C [57 °F]) of the present day, whereas the global temperature of Cambrian times averaged 22 °C (72 °F). Low temperatures during the Neoproterozoic helped to sustain a series of worldwide events known as the Sturtian (748 to 713 million years ago), Marinoan (650 to 600 million years ago), and Gaskiers (595 to 565 million years ago) glaciations. Climate studies suggest that Cambrian temperatures were the norm for most of the
Phanerozoic Eon (the last 541 million years), and these were exceeded only by a brief increase during the
Permian Period near the end of the
Paleozoic Era. Cooler periods, similar to the average global temperature of the present day, occurred during the end of the Ordovician, Late
Carboniferous, Early Permian, Late
Jurassic, and Early
Cretaceous periods, as well as near the end of the
Oligocene Epoch."
Our current temperature world wide is around 14 to 15 degrees Celsius and is variations of that temperature are still within current chaotic state of the post-Pleistocene earth.
The point is that the levels of carbon dioxide is increasing a little but the earths natural response to increased carbon dioxide is increased vegetation growth and in geologic time the banking of carbon due to increased hydrocarbon clutter (
downed trees, prairies, bogs, etc.) has kept us in this chaotic state for almost 12 millenniums, the previous chaotic state or the Pleistocene had more dramatic swings with ice flows (glaciers) over most of Canada and much of the northern parts of the lower 48 states. These periods of glaciation waxed and waned over a period of 1.8 million years; that was a different chaotic state.
The real question is do we have enough data and knowledge to know if even understand the current chaotic state and are we in danger of a paradigmatic switch to another chaotic state.
Raising the average temperature of the earth's exterior by 5 degrees Celsius would put us into a new chaotic state but would it be warming or cooling state. The Elephant in the corner is the engine in this chaotic state involves warm equatorial waters heading toward the north pole and warming Europe, North America, northern Asia and southern equatorial currents warming the southern hemisphere land masses except Antarctica which is surrounded by a circle of currents much like Indians around a wagon train. The earth's response is to stop the currents flowing, make much of Europe and Canada colder and well "Global Cooling"
My humble opinion (
Yes I don't text) is that man is pushing the limits of our current chaotic state and we will have marginal changes (
more storms, more cold and more heat) in different areas of the world as we melt banked water overland (
who cares about the artic ocean, it is floating) and reduce the total area of land (
Goodbye Bangladesh) and man will retreat from the rising waters and put more stress on the existing land.
At sometime we may (
not will) break out of our current chaotic state and something dramatic might (
not will) occur which in the new state might be global cooling, global warming or global rapid fluctuations without a discernible trend.
To paraphrase some Native Americans traditions man should live today with an eye to the future of the 7th generation (
say 140 years) and we are not doing that on earth today. We are prodding the climate change bear.