Basics of Climate Change

How Long Ago Did We Know Global Warming Was Happening?

Earth is warming, and we near the point of no return if we are not already past it due to politicians who are deeply in denial. We have known for quite some time, though it's actually quite shocking to realize how far back we knew that carbon dioxide could warm the atmosphere. It's crazier to realize that scientists knew so long ago that it was already happening.

When Did We First Know?

Because there were so many steps along the way, it's hard to pin down one date for when we knew about global warming/climage change. To try to answer the question based on my reading on the topic, I'd say the 1950s with the first major warning in 1962, 54 years before I wrote this article.

A Summary of Environmental Science & CO2

We've known since 1896 that a reduction in carbon dioxide would cause a cooling effect, conversely an increase could create a warming effect. Svant Arrhenius correctly predicted that one day humans may cause enough emissions to create global warming.

Thankfully, a few scientists had measured CO2 concentration in the atmosphere as far as a hundred years back. Not quite far enough as the Industrial Revolution began in the mid-1700s but it was better than nothing. As early as 1938 a scientist named Guy Stewart Callendar used that data and proposed that there was an increase that could cause temperatures to rise, but back then other scientists disagreed with his findings and he was quite far off in how long it would take becaus of limited information.

Callendar's research turned out to be incredibly important, though he was looking to figure out what caused the ice ages and actually thought the warming may be beneficial. That's how science works, sometimes you discover one thing when studying another, and sometimes you're wrong on the effects it may have. Better information would not be found until computers made it possible, because of complex physics with regard to how CO2 interacts with radiation in the various layers of the atmosphere.

In the 1950s physicists named Gilbert Plass and Roger Revelle began to warn the world that greenhouse gases could become a problem one day. Previous scientists had not thought to account for increases in population and industry and the effect that could create. A Russian named Mikhail Budyko did take these factors into account and delivered an even stronger warning in 1962, but the warnings were not taken seriously by the public nor politicians.

Many other scientists are noteworthy on our path to understanding the situation we are in today. This is a very brief summary to answer how long we have known about the potential for climate change to have a dramatic warming effect. You can find some very interesting information if you're looking for something more in-depth to explain how we discovered this: I highly recommend this page from the American Institute of Physics if you're interested in the history of climate science.

What We Can Learn

I remember 'save the rainforests' as a kid, and the hole in the ozone layer (unrelated to global warming). Those issues seem long gone, wich much more dire predictions about our planet's future. Climage change seems like new information but it's rather old now, it's being studied more heavily because we need to know more to prepare. We can learn from this that global warming and climate change are not something scientists pulled out of their backsides to make Environmental Sciences a well-paying career. Nor is it some green energy conspiracy to scare the world into spending trillions upgrading power plants to fulfill energy demands. Nor are the Chinese behind it, in a grand conspiracy to tank the economy.

Just because it didn't hit the mainstream media until the 2000s, and just because people didn't raise it as a major political issue until then, doesn't mean it hadn't already been discovered. Some actions have been taken, such as the UNFCCC in 1992, but they haven't been enough. It's not a war on coal or oil. We've known for 54 years this could become a problem, and growth was even more explosive and the rapid than those pioneering scientists could have known. That the potential for bad things to happen is so high is why it's in the spotlight so often. It's a very real problem and we will see changes in our lifetimes.

Further Reading
Svante Arrhenius
Guy Stewart Callendar
Roger Revelle
Gilbert Plass
Mikhail_Budyko