When did Global Warming begin?

Victorian times with the industrial revolution

The earth has always gone through periods of heating and cooling. When the dinosaurs roamed the earth the average daily temperature was very high. During the Ice Age the temperatures were extremely low. During the different time periods it could be attributed to various different things such as Milankovitch's cycle, Volcanic Fissures, algae being eaten too fast by trilobites and other sea life, and lots of other variables. For the records Geologists know this because of two factors. The abundance (and loss) of a type of fossil at specific point in the time line, and secondly because certain types of rocks form under certain circumstances. Example Coal (dominantly a marshy environment), dolomite (an environment like Saudi Arabia) etc. Oh and of course geologists do dating on rocks in order to determine their age, it's pretty accurate really. Yes, there is debate over it's accuracy, but that's usually by people who don't really understand the process or calculations involved in calculating half-lives. It's calculated by statistical data by the way, and it's a fun experiment to conduct in a physics class.

t's nearly impossible to overstate the threat of climate change.

Global warming will have catastrophic effects such as accelerating sea level rise, droughts, floods, storms and heat waves. These will impact some of the world's poorest and most vulnerable people, disrupting food production, and threatening vitally important specie setc.

That's an interesting question.

Global Warming is a big deal, so it should be easy enough to see when it started by looking at a graph of annual temperature, shouldn't it?

Here is a graph of a well known temperature record... except I have removed the 'year' labels.

Can you pick when global warming started from this graph?

http://farm9.staticflickr.com/8253/8630817384_7725...

Edit. 'That guy' has told you how to spot it in the graph. You are looking for "the massive increase in the amount and rapidity of the warming"

Edit.

Here is the same chart with the years labeled.

http://farm9.staticflickr.com/8535/8630817394_2f82...

Cmon man thats like asking when did dinosaurs begin pooping? Since Forever. Have you smelt that stuff before, that is how global warming started. All that methane gas.

It's always been a thing, it's how the world works. This process is what keeps our world warm and hospitable. If you're talking about the over warming of the planet, then it would be the industrial age when we started mass burning of fuel.

There isn't a direct answer to when global warming began. Some say that it started about the second half of 20th century by humans, others say that it is a natural process that started about 18,000 years ago. :)

When some crooks realized that the earth wasn't going into an imminent Ice Age.

Life magazine of January 3, 1970, stated: “Scientists have solid experimental and theoretical evidence to support . . . predictions” such as: “In a decade, urban dwellers will have to wear gas masks to survive air pollution,” and “increased carbon dioxide in the atmosphere will affect earth’s temperature, leading to mass flooding or a new ice age.”

So in the 80s they changed the disaster to 'Global Warming'.

That's like asking,

        "When did loud noises begin? Didn't they begin millions of years ago?"

An absolutely useless and stupid question.

Of course loud noises existed a long time ago. Doesn't mean that supersonic booms from shock waves created by jets aren't recent loud noises and created by humans.

Significant levels of anthropogenic global warming are recent. The fact that the Earth has enjoyed global warming effects for longer than humans have existed changes none of that conclusion.

Yes, but the massive increase in the amount and rapidity of the warming only occurred in the last 150 years

It looks like the small amount of warming we've experienced over the last several decades began sometime in the early 1980's. http://www.woodfortrees.org/plot/hadcrut3gl/from:1...

But that's just plain warming... man-made Global Warming never existed.

The Great Global Warming Swindle

http://www.youtube.com/watch?v=YtevF4B4RtQ

Global Warming Doomsday Called Off

http://www.youtube.com/watch?v=fr5O1HsTVgA&playnex...

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