At the risk of pissing people off, I will keep this brief. There are many sources that debunk the widely quoted 95% (its actually 97%) number. Its based on a sample of scientists, many of whom were not climate experts, and many of whom didn't actually believe any warming was human induced. But its a figure widely quoted by politicians to push their cause. Everyone gets on the bandwagon because there is billions/trillions to be made in climate change zealotry. Google "Global temperatures last 2000 years and you will find any number of charts showing temperatures today are much lower than the Medieval warm period. The Earth has undergone periods of change over billions of years, including vast amounts of time when there was no ice at the poles. Polar ice is actually a relatively recent development. Global warming is NWO socialist agenda masquerading as environmentalism - driving massive worldwide wealth redistribution away from Western democracies (via environmental taxation) to developing countries like India and China, who continue to build thousands of coal fired power stations every year with barely a peep from the climate scientists. It has been proven that Australia could literally shut down completely, and it would not make one iota of difference to the Earths climate. Venezula is a Socialist country and is a basket case. Trump doesn't practice "pure capitalism" - there are vast amounts of regulatory controls that underpin the US system. There are many schools of thought on what caused the Great Depression - the monetarist view is that policy mistakes by regulators were the major causal factor, not unbridled/unregulated capitalism. The Roosevelt "New Deal" may have helped limit the pain of the Depression, but it was WW2 that actually ended it through massive government war programs. As for the GFC - one of the root causes was the Clinton (typically leftist) intervention in the housing market, loosening controls such that loans were extended to sectors of the economy that should never have been offered a loan. Those loans were bundled as CLO's and CDO's and sold as prime investments, when they were anything but.
I've been interested in climate issues since I was 8 years old Terry and it was one area I considered working in. I'm not socialist and my attitude towards climate concerns is well over 30 years old, well before it became fashionable. You raised the same old argument put forward by those who don't believe in human influenced climate change that has been bandied around for years.
Lets get some true science into this. Firstly talking about climate issues billions of years ago is failing to see that each epoch has its own climate conditions that affect the ecosystem. If we lived for example during the Cretaceous period, the temperature would about around 6 degrees on average hotter than today. Life thrived in the Antarctic at that time because the poles had no ice. But sea levels were at least 70 metres higher and none of the coastal areas we tend to build cities on would be above sea level. Further humans would not have survived in the tropical areas for many reasons not just temperature which was a few degrees higher on average (tropical areas don't rise in temperature as quickly as temperate and polar regions). There was no grass at all, because grass relies of cooler drier conditions. Grass developed only in the last few tens of millions of years. So no cereal. Most of the vegetables and fruit would be of a different variety, more suited to hot, wet conditions. But climate generally changes slowly not rapidly, giving the ecosystem time to adapt, mutate and even move. Earth was much hotter between 250 - 50 million years ago. It was also probably encased by ice about 600 million years ago (called Snowball Earth by palaeontologists). Many factors change climate including solar insulation and insolation. There are also tectonic factors and where the land plates lie, especially in relation to the poles.
About 50 million years ago India moved from the Antarctic and collided with Asia. This, and the encircling of land masses around the Arctic Ocean, led to a gradually cooling Earth. We now have glaciation periods and ice layers at the poles because of this cooling of the oceans in particular. Humans developed during ice age conditions. We are best suited for these cooler conditions and are food sources are dependent upon those conditions, especially plant life that cant change or migrate in the short term
All life influences temperature, its just how extensive that is. Elephants and hippos actions help maintain the Kalahari delta, in the middle of that desert in the wet season. Anaerobic life forms actually changed the Earth's atmosphere from Nitrogen-Carbon Dioxide to Nitrogen-Oxide, without which large life forms would not now exists. When humans arrived in the Americas, Australia, New Zealand, their actions quickly changed the climate by altering the dominant lifeforms, and especially changing the vegetation best suited for example to fire harvesting. There's nothing unusual about life forms changing climate.
We've changed the climate today through many factors but two stand out. The use of carbon based fuels and the preference for ruminant food animals, especially cattle. One sends CO2 into the atmosphere, the other CH4 (methane). Both are greenhouse gasses, because if you understood your chemistry, both retain back radiation (primarily infrared) for longer than oxygen and nitrogen can. Mind you without CO2 the average temperature would be -15 degrees on average and the Earth would be iced over. Water is also a greenhouse molecule and anyone living near the ocean has proof of that because the oceans hold heat and make evenings warmer on the coast than in the country.
It is impossible to alter CO2 levels, without changing temperature. CO2 is Earth's thermostat. During the Ice Age 20,000 years ago the CO2 level was at 180 parts per million and consequently 6 degrees cooler on average (doesnt need much to have an influence). During the pre-Industrial period it was 280 parts per million. It is now over 400 parts per million in the atmosphere (those readings come from Ice Cores and from readings taken over the past hundred years by international authorities). It is impossible for this not to impact on climate and that's why the scientific community agree.
As for other climate changes, yes the temperature was high around 750-1300 AD. But that has now been surpassed. It was actually a degree cooler during what was called the Maunder Event from 1300-1800, much of it caused by reduced sun spot activity. And there are cycles such as the El Nino and La Nina, as well as longer cycles. But these have been factored into studies.
In reality our climate should be cooling because if you know anything about the accredited Milankovich cycles, relating to the Earth's orbital cycles of 26,000, 41,000 and 100,000 years, we should be moving out of the Holocene and towards ice age conditions again, not getting hotter, a further example of the effect humans are having on climate. Many scientists are now describing our effect on climate as bringing about what's now called the Anthropocene, potentially thousands of years of climate caused by human influence.
The political issues I discuss later.
