History of Climate Science

[ryacko]

To my knowledge the start of climate science began before the theory of tectonic drift was accepted. Fossils of tropical plants were found in arctic climates, bringing speculation that the Earth was much warmer.

Then there were fears of global cooling in the seventies.

Maybe due to particulate pollution reduction global cooling stopped.

Fears of global warming emerged after Al Gore's documentary is shown widely. Global warming becomes the more vague climate change (climate has to change since the Earth isn't a steady state system). There is a major -gate, which later resulted in several websites (some government) retracting statements such as the Himalayan ice caps melting by 2020.


Sometime due to iron minerals, a theory is formed about a "snowball earth."


Am I unaware of any details? Genuinely interested in other facts. The history of science interests me more then the science itself, do find it amazing what people previously thought. And yes, I agree that we are heading away from an ice age.

[madd0ct0r]

i always thought 'global warming' became 'climate change' because global warming is a GOOD thing in moderation - look at mars.

your initial point is correct - one theory was the earth was larger and warmer, shrinking as it cooled with the crust wrinkling into mountains.

[Zaune]

i always thought 'global warming' became 'climate change' because global warming is a GOOD thing in moderation - look at mars.

My impression was that it was more because nobody can be exactly certain what will happen to the climate when we finally hit the point of no return, or even when that point of no return will be. (There's a school of thought that says we already passed it.) We still haven't really modelled its inner workings except in very broad strokes.

[Simon_Jester]

Then there were fears of global cooling in the seventies.

Maybe due to particulate pollution reduction global cooling stopped.

That, and the initial studies that indicated it was a problem were undermined by later results. When someone took the early simulations that showed horrible nuclear winters from soot thrown into the air, and used more accurate assumptions about how the Earth's ecosystem works, the whole thing turned out to be overblown.

Fears of global warming emerged after Al Gore's documentary is shown widely. Global warming becomes the more vague climate change (climate has to change since the Earth isn't a steady state system). There is a major -gate, which later resulted in several websites (some government) retracting statements such as the Himalayan ice caps melting by 2020.

This paragraph is basically wrong in every possible detail. People were worrying about global warming twenty years before Al Gore even thought about making a documentary. It was well documented; the first person to investigate the problem of carbon dioxide causing global warming was Arrhenius, in 1896. All Al Gore did was make a movie to sum it up for people who didn't know very much about it- he didn't invent or create any new information of it.

Now, knowing how this carbon dioxide (CO2) warms the air, and how much it warms the air, and how much the extra CO2 we create makes the air warmer, is a complicated problem. To figure this out we measure the temperature around the world, and we use computer simulations.

Some of those simulations, especially in the early days, weren't too accurate. So some of them thought there would be a LOT of global warming: enough that we could very easily cause horrible disasters, like the "runaway greenhouse effect" that made Venus an uninhabitable hellhole with an atmosphere of superheated high pressure acid.

Other simulations underestimated the problem. You don't hear too much about those today. Because it's not convenient for the oil industry to talk about them, so they don't pay people to talk about them.

As we refined our knowledge, built better computers and wrote better programs, the predictions got more and more accurate. We got more able to predict temperature, and different predictions made by different groups started lining up- because they were now getting the same answer from different methods, which is a good sign.

If two people disagree on a sum, at least one of them is wrong, and maybe both. If they both agree despite using different methods to get it... they probably know what they're doing. The odds of both of them wrong go down, because there are many many ways to make mistakes, but few ways for two people to get the same answer by making different mistakes.

So basically, if you look at actual people who study this professionally, they all agree that global warming is happening now, will continue to happen, and will get a lot worse, especially if we don't stop pouring extra CO2 into the air. Many of them have been telling us the same thing for twenty or thirty years. Some of their predictions are even starting to come true- the ice cap at the North Pole gets a lot smaller in summer these days than it used to twenty years ago, for example. Glaciers that used to be permanent on top of mountains are now melting. And so on.

"Coming out of an Ice Age" wouldn't explain that.

The people who deny this are mostly just... wrong. Often they're being supported or paid by powerful rich people, who have a vested interest in us not doing anything to stop the climate from getting worse. Or they have loony conspiracy theories about all the scientists having decided to fake up this big climate problem.

There really is very little controversy about global warming among people who know their stuff.



Now, why do people say "climate change?" Several reasons. The big one is that "warming" can sound pretty good if you're under a foot of snow- but it's more complicated than that, I'll explain. See, "global warming" doesn't just mean "every place gets X degrees hotter all the time." It means "the Earth's atmosphere stores more energy."

So global warming means that weather of all kinds will get supercharged. More energy in the air means more energy to form powerful storms- even tornadoes and hurricanes. More heat means more water evaporating from the oceans, which means more moisture in the air, which means more precipitation- not just rain in summer, but also snow in winter. Yes, you can actually get bigger snowstorms from global warming, which is one reason people might say "climate change," to avoid that confusing fact.

More heat can mean that ocean currents move in different directions- for example, the Gulf Stream, a current that carries hot water from the Carribbean to Europe, may shift or die out. This could make the Carribbean hotter... but it can also make Western Europe colder, because it's not getting its hot water heater anymore. More heat can change chemical reactions and affect the acidity of seawater. More heat can do all kinds of complicated things. Many of them will be bad, or at least bad for certain large groups of people.

Because the way we run the world today, the way we live and work, and especially the way we get our food, all depend on certain assumptions about how weather and climate work. If those assumptions stop being true, then we have big problems.

For example, we assume that certain flood plains are safe to build on, because a terrible flood will only come once every hundred years. We can afford to fix up the city every hundred years, right? But what if climate change means that such floods now happen every twenty years? Now it could be very expensive to fix all the damage- and whole cities could get flooded out, because they're destroyed by floods over and over until we stop even trying to rebuild them. After one flood, the government refuses to pay so that people can move back. Suddenly the people who live there are refugees. Not good.

Or what if we're used to having rainwater to provide the water for crops in a region that feeds many millions of people? If the rains stop coming, maybe people will starve- and certainly food will become more expensive. Not good.

And so on. It's complicated, and we can safely assume that any major random change in the Earth's climate will be bad for us, because the way we run our civilization depends on so many assumptions about what we can do, and what we don't need to do.

Sometime due to iron minerals, a theory is formed about a "snowball earth."

There appears to have been a time in the distant past, more than 650 million years ago*, when the Earth was very cold, and most of the Earth's surface was covered in ice and snow, including the sea.

*This is three times longer ago than the birth of the first dinosaurs. So far as I know, it is before multicellular life evolved at all.

Am I unaware of any details? Genuinely interested in other facts. The history of science interests me more then the science itself, do find it amazing what people previously thought. And yes, I agree that we are heading away from an ice age.

There are a mountain of relevant details, and many of them which you should probably learn. I have neither the time, the knowledge, nor the confidence to tell them all.

[D.Turtle]

Then there were fears of global cooling in the seventies.

This was mostly a thing in the popular press. In the scientific community they were a small minority opposed by a large majority expecting increased temperatures or having no position on the matter.

To be more exact (from Realclimate.org:

Between 1965 and 1979 we found:
7 articles predicting cooling
44 predicting warming
20 that were neutral

Fears of global warming emerged after Al Gore's documentary is shown widely. Global warming becomes the more vague climate change (climate has to change since the Earth isn't a steady state system). There is a major -gate, which later resulted in several websites (some government) retracting statements such as the Himalayan ice caps melting by 2020.

The term climate change or climatic change is older than the term global warming. The term climate change was already around in 1939, while global warming didn't appear until 1975. The reason that the term climate change has become so widely used is that Frank Luntz advised Republicans to use the term as it evokes less alarm than the term global warming. In the scientific community global warming is mostly used to describe the pure temperature change, while climate change is used to include all the effects from increased CO2 emmissions (hence the Intergovernmental Panel on Climate Change - first created in 1988).

Most information from this video:

[Vehrec]

Did I hear somebody say Snowball Earth? Well, if you're talking about that, you should know that the evidence for it is glacial deposits, not iron oxide. And when I say glacial deposits, I mean erratic boulders in very fine grained stone, which are always overlaid by a layer of carbonate. So you go straight from glaciers to extremely tropical in terms of climate. How else do you interpret that evidence except as the earth violently freezing and thawing in some kind of perverse cycle? The earth goes white, stops absorbing heat, and we have to wait until the whole thing gets enough CO2 from volcanoes to melt the entire planet despite the incredibly low albedo.

And I say cycle, because this happened at least four times.

[Guardsman Bass]

I read somewhere that continental arrangement may have played a role in creating the "Snowball" conditions, in two ways.

1. Continents back then had no vegetation, which meant that they had a significantly higher albedo than the oceans. When the continents were all close to the equator, a greater amount of the Sun's light was reflected instead of being absorbed and re-radiated as infrared/heat.

2. The break-up of a super-continent (such as Rodinia, an early one in the Precambrian Period) tended to cause a ton of weathering that drew down large amounts of CO2 from the atmosphere, cooling the planet.

As for climate change, the term is more useful than global warming. Global mean temperature rises translate to a vast range of climatic changes at the local level, including some areas where temperatures might actually decline for a while.