Climate change: Milankovitch cycles, Ice ages, and Greenhouse Gases.

[Sea of red]

Glacial changes in the Earths history can be traced back via ice cores, and can be deduced from a number of factors. The Earths eccentricity is the first of these factors in changing on a time-scale of around 100,000 years. Eccentricity is simply the changing of the Earths orbit from being more like more elliptical, to being less elliptical with time. The second of these is changes in the axial tilt from 21.5 to 24.5 degrees. The third factor, is the Earths precession or wobble as it orbits the sun. This changes the North Star from being Polaris, to Vega.

These things put together are called the Milankovitch cycles.

This illustrates the Earths precession some fair justice:



It is these small changes that change the distribution of sunlight radiation on the Earth and radically alters the seasons, climate, and brings into and out of Ice-ages an Holocene.



We can also see looking back, that green house gases (GHC) both follow and drive climate. The reasoning is simple: as the climate warms, more GHG's are released into the atmosphere, further heating the earth, and this feed-back continues until the Earth reaches balance again. This is why the argument that GHG lag temperature is a non-sequitur; GHG's act as a feedback that amplifies temps.


See why climatologists and atmospheric physicists take climate change seriously? Again, the science is pretty settled.

[tabibito]

So what would rule out these factors being the main driving force (exacerbated to some degree by human activity) behind the current warming trend - particularly with the Earth coming out of a cooling period (mid 1700s) induced it seems largely by volcanic activity?

[Sea of red]

So what would rule out these factors being the main driving force (exacerbated to some degree by human activity) behind the current warming trend - particularly with the Earth coming out of a cooling period (mid 1700s) induced it seems largely by volcanic activity?

The Little Ice Age (LIA) was largely a period that effected the Northern Hemisphere, and North America and Europe particularly. It's not entirely clear how global it was or the causes behind it, but it's clear that volcanic activity, and the Maunder minimum are co-factors.

The smoking gun that would have debunked human forcings would have been the discovery of a more even warming in the atmosphere, rather than finding acooling in the stratosphere - though other theories could have also prevailed.

[tabibito]

And a more evenly distributed warming would indicate a nett increase in heat being radiated by the sun to account for global warming?
Are interglacial periods shown to be typically the result of that kind of activity?

[Jichard]

So what would rule out these factors being the main driving force (exacerbated to some degree by human activity) behind the current warming trend - particularly with the Earth coming out of a cooling period (mid 1700s) induced it seems largely by volcanic activity?

Because scientists have records of solar forcing through either direct satellite measurements or through proxies like sunspots. They can use those to rule out solar forcing as an explanation of recent global warming. Furthermore, they can measure forcing from other sources (such as volcanoes) and show that those don't explain the recent warming either. Instead, the recent warming is largely anthropogenic, as explained on the other thread, with abundant evidence: http://www.theologyweb.com/campus/sh...global-warming

[Sea of red]

And a more evenly distributed warming would indicate a nett increase in heat being radiated by the sun to account for global warming?

Yes.

Here are the readings for sun spot activity in the past century relative to temperature:


As you can see, temperatures continued to rise even sun spots decreased, while CO2 remained a constant factor.

Are interglacial periods shown to be typically the result of that kind of activity?

It is the resulting effect of the Milankovitch cycles. The third graph in my OP tells the story of the cycles, and how GHG's act as a feedback to temperatures.

[Mountain Man]

Source: The Daily Caller

http://dailycaller.com/2015/06/04/no...arming-hiatus/

© Copyright Original Source

Ain't "adjusted" data great? It can prove anything.

More detail and a look at the nitty-gritty facts and figures can be found here:

http://wattsupwiththat.com/2015/06/0...ing-past-data/

[shunyadragon]

Source: The Daily Caller

http://dailycaller.com/2015/06/04/no...arming-hiatus/

© Copyright Original Source

Ain't "adjusted" data great? It can prove anything.

More detail and a look at the nitty-gritty facts and figures can be found here:

http://wattsupwiththat.com/2015/06/0...ing-past-data/

Old warn out rabbits from Cambrian rocks.

[Mountain Man]

Those articles were posted two-months ago. Not exactly "old and worn out", unless you're referring to the claim that global warming is "settled science" despite having no real evidence to support it.

[TheLurch]

Those articles were posted two-months ago. Not exactly "old and worn out", unless you're referring to the claim that global warming is "settled science" despite having no real evidence to support it.

Here's an article about the adjustments that were actually made, and describes the reasons that they were made, as well as the net effect.
http://arstechnica.com/science/2015/...ming-slowdown/

Can you tell me what's scientifically invalid about what was done?

[shunyadragon]

Those articles were posted two-months ago. Not exactly "old and worn out", unless you're referring to the claim that global warming is "settled science" despite having no real evidence to support it.

What is 'old and worn out' is the hocus bogus argument.

[Sea of red]

Source: The Daily Caller

http://dailycaller.com/2015/06/04/no...arming-hiatus/

© Copyright Original Source

Ain't "adjusted" data great? It can prove anything.

More detail and a look at the nitty-gritty facts and figures can be found here:

http://wattsupwiththat.com/2015/06/0...ing-past-data/

The Daily Caller and Anthony Watts?

Anthony Watts is an idiot that think urban heat island (UHI) effects are contaminating data trends, even after countless climatologists have corrected him on this idea. When Berkley Earth (BEST) created a project to compare trends, Watts stated he would go with whatever they found. And guess what? They found that when comparing trends from 'poor' stations (as Watts called them) to more preferred stations, there was no significant divergences from the known satellite measurements. Then Watts pissed and moaned about the results. Watts claim that NOAA fudged the data is in conflict with the problem that their readings are comparable to independent satellite measurements, while his are in conflict with satellite readings.



And the BEST results:

[Jichard]

Those articles were posted two-months ago. Not exactly "old and worn out", unless you're referring to the claim that global warming is "settled science" despite having no real evidence to support it.

Here's an article about the adjustments that were actually made, and describes the reasons that they were made, as well as the net effect.
http://arstechnica.com/science/2015/...ming-slowdown/

Can you tell me what's scientifically invalid about what was done?

No, he can't tell you, because AGW denialists tend to have no idea what they're talking about.

[Mountain Man]

Here's an article about the adjustments that were actually made, and describes the reasons that they were made, as well as the net effect.
http://arstechnica.com/science/2015/...ming-slowdown/

Can you tell me what's scientifically invalid about what was done?

I think the articles I posted earlier do a pretty good job of putting a pin in that balloon. :)

As the saying goes, "If global warming continues at this rate, it won't be long before our ancestors freeze to death."

[Mountain Man]

The Daily Caller and Anthony Watts?

Anthony Watts is an idiot that think urban heat island (UHI) effects are contaminating data trends, even after countless climatologists have corrected him on this idea. When Berkley Earth (BEST) created a project to compare trends, Watts stated he would go with whatever they found. And guess what? They found that when comparing trends from 'poor' stations (as Watts called them) to more preferred stations, there was no significant divergences from the known satellite measurements. Then Watts pissed and moaned about the results. Watts claim that NOAA fudged the data is in conflict with the problem that their readings are comparable to independent satellite measurements, while his are in conflict with satellite readings.



And the BEST results:

Like I said, you can prove anything with "adjusted" data, although it's rather like painting a target around an arrow and claiming you got a bullseye.

Look, you guys can run around like Chicken Little claiming that the sky is falling if that's what floats your boat. Meanwhile, I'll continue to sleep soundly knowing that the Earth will be perfectly habitable for next few million years.