In our climate discussions, the Medieval Warm Period was often mentioned. After this warm period, there was a cool period, called the "little Ice Age". It wasn't really an "Ice Age", but the rivers in Northern Europe were all frozen solid.
The link below discusses how this climate change affected society. Metmike had already mentioned that great civilizations flourished during warm periods.... easy to explain... more food is growing
The link below details how the Little Ice Age caused hardship.
simple conclusion..... global warming good, global cooling bad
What caused the warm period
I was told excessive volcanic action warmed up the planet, followed by cold and then the debate was on
The only large volcanic action I know of actually cooled the planet due to all the ash floating around and stopping the sun's heat from reaching the earth
However my knowledge is limited thus my question
What caused the warm period
I got into a debate on carbon taxes with people who thought the tax was just fine as I was paying their share
I mentioned the warm period and one thing lead to another with me on the defensive, all by myself
"What caused the warm period"
We don't know, probably the sun was more active with a grand solar maximum, similar to the one that we had last century.
It was similar to even warmer than that 2,000 years ago during the Roman Warm Period and warmer than that around 3,500 years ago during the Minoan Warm Period but the warmest of all was the Holocene Climate Optimum between 9,000 to 5,000 years ago.
How can this be? We are being told that this current warmth is bad and is unprecedented and could have only been caused by CO2 emissions.
It was called an optimum when it was warmer than this because the planet and life on it did BETTER when it was warmer than this. Not my opinion, it's a scientific fact.
It's being called a crisis/emergency today for political reasons...........even though we are experiencing another climate optimum and the best weather/climate in at least 1,000 years and best CO2 levels since humans have existed(still only 50% of the optimal level for CO2).
https://en.wikipedia.org/wiki/Holocene_climatic_optimum
"Temperature variations during the Holocene from a collection of different reconstructions and their average. The most recent period is on the right, but the recent warming is only seen in the inset.
The Holocene Climate Optimum warm event consisted of increases of up to 4 °C near the North Pole (in one study, winter warming of 3 to 9 °C and summer of 2 to 6 °C in northern central Siberia).
"Out of 140 sites across the western Arctic, there is clear evidence for conditions warmer than now at 120 sites. At 16 sites, where quantitative estimates have been obtained, local HTM temperatures were on average 1.6±0.8 °C higher than now. Northwestern North America had peak warmth first, from 11,000 to 9,000 years ago, and the Laurentide Ice Sheet still chilled the continent. Northeastern North America experienced peak warming 4,000 years later. Along the Arctic Coastal Plain in Alaska, there are indications of summer temperatures 2–3 °C warmer than present.[5] Research indicates that the Arctic had less sea ice than the present."
metmike: 40 years ago, climate science and scientists agreed on the above. Then, climate science was hijacked by the United Nations and progressive activists for political agenda. They established the IPCC as the world climate authority for all governments and scientists. The IPCC rewrote climate history to take out the previous warm period and told us that this is unprecedented.
Yes, that's really what happened with 100% certainty.
Here are my last 2 discussions on it:
Scientists coming out of the woodwork-no climate crisis! October 2019
https://www.marketforum.com/forum/topic/41293/
Climate change, pollution, and the great civilizations of the past: Exactly how climate science was hijacked for the political agenda. September 2019
https://www.marketforum.com/forum/topic/39960/
If you really want to learn about authentic climate science, there is much more here:
https://www.marketforum.com/forum/topic/27864/
It's because almost nobody understands climate science that they were able to do this. 25 years ago, I was also a believer in much of it.
Then............the data kept coming out that contradicted the computer simulations being used and I researched legit climate history to see how life benefited from periods even warmer than this.
That's how the gatekeepers can tell you anything they want to and make the absurd claim that it represents 97% of climate scientists......based on cooked up studies.
This is very wrong.
We are warming beneficially at 0.13 deg. C/decade.
Bad stuff?
1. We have more heavy rain events as well as 2. a slight increase in Summer heat waves in some places. 3. Oceans are increasing at 1 inch/decade.
That's it.
The rest of whats happening is massive climate optimum stuff for life on this greening planet.
Think about this. What happens to life in the middle and high latitudes during the Winter? Some creatures migrate south to avoid the killing cold. Some will hibernate. Plants go dormant or they die. Cold kills life, including human life.
The warming has been the greatest in the coldest places during the coldest times of year(Winter) in the Northern Hemisphere.
CO2 is a beneficial gas in all fields of science.......biology, agronomy, zoology, climate science, etc. Only in politics is it defined as pollution.