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The industrial revolution blossomed on easily-accessed fuels – fossil fuels. Those fuels are all carbon-based. They all produce lots of easily-accessed energy when burned to produce carbon dioxide (CO2).
Humans didn't know it to begin with but a carefully-controlled amount of CO2 is necessary to maintain a climate that is friendly to life as we know it. The earth, sometimes called “Mother Earth”, and sometimes called “Gaea” developed a cooperation between different parts of it's environment to keep CO2 at a level that kept the climate in control for thousands of years.
CO2 (and some other gases) act as a blanket. Sunlight energy enters our atmosphere and bounces off of whatever surface it runs into. The reflected energy is mostly infra-red energy as opposed to the visible light that came in. The CO2 keeps the infra-red energy inside the atmosphere. Increased CO2 keeps more energy in. More energy becomes heat and the temperature goes up.
The earth radiates energy as a “black body”, and the key information to know about that is more heat is radiated if the body is a higher temperature. So if we have more CO2 in the atmosphere, the earth gets enough hotter that the black-body radiation grows just large enough to balance the incoming energy.
The burning of Carbon-based fuels did good things that allowed human civilization to grow as never before. Since doing so was dependent on the availability of abundant energy, and readily-available energy was carbon based fossil fuels, our use of them grew on an exponential curve correlated to our population growth.
Thus, our disturbance of the atmosphere's CO2 balance went from being a slow disturbance to an ever-growing one. One that has nearly reached limits beyond which life forms such as ours and our food sources may no longer be so well supported on Earth.
That's the beginning, but there are more layers. Remember, there was a feedback system that kept things in amazing control for about 800,000 years. This gave humans the “Garden of Eden” planet that allowed the transition from hunter-gatherer behavior to farming, and cooperative society with lasting communities and aliances.
But, our use of those fuels disturbed that premise with secondary consequences: