It's only going to go up until serious changes happen because it's a chemistry thing.
What's different about global warming today is humanity adds carbon dioxide (CO2) to the atmosphere. CO2 acts lilke a blanket covering the Earth. Adding more CO2 to the atmosphere is like adding more blanket covers. For some reason a lot of people in the United States cannot figure this out; it's interesting how so many people deny climate science today like so many people denied tobacco's role in causing lung cancer, or the number of people that denied the reality of the human immunodeficiency virus (HIV), AIDS, or the germ theory of disease.
Thanks to climate science we know that Earth's atmospheric content surpassed 400 parts per million of carbon dioxide molecules in the atmosphere this decade! In 1750 it was like 280 ppm.A chemical compound, CO2 has one carbon atom and 2 oxygen atoms. It has only a 0.038% volume in Earth's atmosphere. As tiny as this volume may seem, it's enough to keep Earth's temperature at a comfortable level for humanity and other species.
But like Tabasco sauce, a chemistry thing, for example, a little bit goes a long way to heat things up. We know that humanity adds more CO2 to the atmosphere by burning fossil fuels; fossil fuels release CO2 into the atmosphere. Science now proves that bagan adding dangerous amounts of CO2 to the atmosphere beginning around 1800. The Industrial Revolution receives credit as the source of our contribution; we've burned fossil fuels for over 250 years to live better.
A few scientists figured out the consequences of burning fossil fuels early on. Now thousands of scientists understand how adding CO2 to the atmosphere increases global warming. Some people figured it out because they intuited it. They sensed something would happen because burning fossil fuels had never been done on such a great scale. Now there's 1 billion cars burning gasoline, not to mention coal burning for manufacturing and heat. Then there's the thousands jets flying every day. There's much more going on.
We know that thawing permafrost will release great amounts of CO2 to the atmosphere. It's happens right this minute. As the Earth warms so too does the surface of the Earth. Because permafrost was frozen solid long ago, it holds trillions of tons of CO2. Now when it thaws out it will release this CO2. This is called a "feedback loop." The warmer Earth becomes, the faster CO2 will enter the atmosphere.
By cutting down forests we also release even more CO2 as trees decompose. Although there may be more trees on Earth today and in then in recent years due to tree farming, we should not forget there's a lot of difference between a tree farm and old-growth forests. There's no such thing as "forest seeds" either. That's beside the point, though.
Other sources of CO2 adding to Earth's warming include volcanic eruptions, the combustion of organic matter as noted above for trees and permafrost. So we play a part in adding to Earth's protective blankets, their recapturing the sun's energy. Also, more feedback loops exist, but that's another story.
Most notably overall, the Industrial Revolution receives credit for the burning of fossil fuels to create energy. This energy has allowed humanity to create factories to produce machines capable of consuming billions of tons of fossil fuels every year. As a result many billions of tons of carbon dioxide enter Earth's atmosphere.
Wars fought over land for natural resources like coal and oil plagued humanity for hundreds of years.
Plastic in general and plastic bags in particular strangle seagoing turtles. Already at risk of extinction, seagoing turtles find floating plastic bags closely resemble jellyfish. So they gulp these fossil fuel products. Ironically, the plastic will outlive the turtles remains, but for their shells. Two giant, plastic islands floating around in the Pacific Ocean consist plastic waste. Sea life dies in these plastic traps. We have no idea, either, what sort of chemicals leach from floating plastic.
It now climbs to 0.04 (4.6 per 1,000,000) at times. Even if we stopped adding CO2 yesterday, it would continue to climb in concentration for decades, if not longer; plus, like Tobasco sauce, a little goes a long way.
To be clear, CO2 is a greenhouse gas that interferes with the earth’s ability to radiate back out to space the heat it receives from the sun, trapping it. The more heat that is trapped, the hotter the earth will get over time on average.