Ancient farmers spared us from glaciers but profoundly changed Earth's climate

September 6, 2018 by Kelly April Tyrrell, University of Wisconsin-Madison
Credit: CC0 Public Domain

Millenia ago, ancient farmers cleared land to plant wheat and maize, potatoes and squash. They flooded fields to grow rice. They began to raise livestock. And unknowingly, they may have been fundamentally altering the climate of the Earth.

A study published in the journal Scientific Reports provides new evidence that ancient farming practices led to a rise in the atmospheric emission of the heat-trapping gases carbon dioxide and methane—a rise that has continued since, unlike the trend at any other time in Earth's geologic history.

It also shows that without this human influence, by the start of the Industrial Revolution, the planet would have likely been headed for another ice age.

"Had it not been for early agriculture, Earth's would be significantly cooler today," says lead author, Stephen Vavrus, a senior scientist in the University of Wisconsin-Madison Center for Climatic Research in the Nelson Institute for Environmental Studies. "The ancient roots of farming produced enough carbon dioxide and methane to influence the environment."

The findings are based on a sophisticated climate model that compared our current geologic time period, called the Holocene, to a similar period 800,000 years ago. They show the earlier period, called MIS19, was already 2.3 degrees Fahrenheit (1.3 C) cooler globally than the equivalent time in the Holocene, around the year 1850. This effect would have been more pronounced in the Arctic, where the model shows temperatures were 9-to-11 degrees Fahrenheit colder.

Using climate reconstructions based on ice core data, the model also showed that while MIS19 and the Holocene began with similar carbon dioxide and methane concentrations, MIS19 saw an overall steady drop in both while the Holocene reversed direction 5,000 years ago, hitting peak concentrations of both gases by 1850. The researchers deliberately cut the model off at the start of the Industrial Revolution, when sources of greenhouse gas emissions became much more numerous.

For most of Earth's 4.5-billion-year history, its climate has largely been determined by a natural phenomenon known as Milankovitch cycles, periodic changes in the shape of Earth's orbit around the sun—which fluctuates from more circular to more elliptical—and the way Earth wobbles and tilts on its axis.

Astronomers can calculate these cycles with precision and they can also be observed in the geological and paleoecological records. The cycles influence where sunlight is distributed on the planet, leading to cold glacial periods or ice ages as well as warmer interglacial periods. The last glacial period ended roughly 12,000 years ago and Earth has since been in the Holocene, an interglacial period. The Holocene and MIS19 share similar Milankovitch cycle characteristics.

All other interglacial periods scientists have studied, including MIS19, begin with higher levels of carbon dioxide and methane, which gradually decline over thousands of years, leading to cooler conditions on Earth. Ultimately, conditions cool to a point where glaciation begins.

Fifteen years ago, study co-author William Ruddiman, emeritus paleoclimatologist at the University of Virginia, was studying methane and carbon dioxide trapped in Antarctic ice going back tens of thousands of years when he observed something unusual.

"I noticed that methane concentrations started decreasing about 10,000 years ago and then reversed direction 5,000 years ago and I also noted that carbon dioxide also started decreasing around 10,000 years ago and then reversed direction about 7,000 years ago," says Ruddiman. "It alerted me that there was something strange about this interglaciation ... the only explanation I could come up with is early agriculture, which put greenhouse gases into the atmosphere and that was the start of it all."

Ruddiman named this the Early Anthropogenic Hypothesis and a number of studies have recently emerged suggesting its plausibility. They document widespread deforestation in Europe beginning around 6,000 years ago, the emergence of large farming settlements in China 7,000 years ago, plus the spread of rice paddies—robust sources of methane -  throughout northeast Asia by 5,000 years ago.

Ruddiman and others have also been working to test the hypothesis. He has collaborated with Vavrus, an expert in climate modeling, for many years and their newest study used the Community Climate System Model 4 to simulate what would have happened in the Holocene if not for human agriculture. It offers higher resolution than climate models the team has used previously and provides new insights into the physical processes underlying glaciation.

For instance, in a simulation of MIS19, glaciation began with strong cooling in the Arctic and subsequent expansion of sea ice and year-round snow cover. The model showed this beginning in an area known as the Canadian archipelago, which includes Baffin Island, where summer temperatures dropped by more than 5 degrees Fahrenheit.

"This is consistent with geologic evidence," says Vavrus.

Today, the Arctic is warming. But before we laud ancient farmers for staving off a global chill, Vavrus and Ruddiman caution that this fundamental alteration to our global climate cycle is uncharted territory.

"People say (our work) sends the wrong message, but science takes you where it takes you," says Vavrus. "Things are so far out of whack now, the last 2,000 years have been so outside the natural bounds, we are so far beyond what is natural."

The reality is, we don't know what happens next. And glaciers have long served as Earth's predominant source of freshwater.

"There is pretty good agreement in the community of climate scientists that we have stopped the next glaciation for the long, foreseeable future, because even if we stopped putting into the atmosphere, what we have now would linger," says Ruddiman. "The phenomenal fact is, we have maybe stopped the major cycle of Earth's climate and we are stuck in a warmer and warmer and warmer interglacial."

Explore further: Mounting evidence suggests early agriculture staved off global cooling

More information: Stephen J. Vavrus et al, Glacial Inception in Marine Isotope Stage 19: An Orbital Analog for a Natural Holocene Climate, Scientific Reports (2018). DOI: 10.1038/s41598-018-28419-5

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Zzzzzzzz
3.6 / 5 (13) Sep 06, 2018
And now human's effects on the planet's climate are accelerating into an extreme that humans may not be able to survive. We better stop emitting greenhouse gases, and quickly figure out how to reduce the concentrations we've already emitted. We are not trying to save the planet, we are trying to save ourselves.
Old_C_Code
2.1 / 5 (15) Sep 06, 2018
Things are better now than ever before in history: less crime, less poverty, LESS POLLUTION, longer lives, more electricity; throughout the world.

What greenhouse gases, CO2? it rose 30%, nothing happened. And we don't have massive volcanoes spewing out S2O4 and raising the temp around them hundreds of degrees hotter like Venus.
Parsec
3.4 / 5 (8) Sep 06, 2018
And now human's effects on the planet's climate are accelerating into an extreme that humans may not be able to survive. We better stop emitting greenhouse gases, and quickly figure out how to reduce the concentrations we've already emitted. We are not trying to save the planet, we are trying to save ourselves.


Actually, the truth is that the ultimate scenario doesn't entail actual extinction for the human race, but simply the obliteration of several billion human lives and the subsequent improvisation of the rest.

Human beings are like cockroaches. Easy to kill in job lots, but very difficult to eradicate completely. Of course resource wars that escalate into nuclear conflicts would do the trick.

What is at sake is those billions of lives, and the trillions in cleanup costs that continue to multiply exponentially the longer we put off doing something.
Old_C_Code
2.3 / 5 (9) Sep 06, 2018
Things are better now than ever before in history <= if you think this is bad, you are one miserable person.
petersonwalter
3.7 / 5 (3) Sep 06, 2018
Wouldn't agriculture produce more plants capable of utilizing CO2 and producing oxygen?
zz5555
3.5 / 5 (8) Sep 06, 2018
Wouldn't agriculture produce more plants capable of utilizing CO2 and producing oxygen?

Possibly. However, agriculture is either eaten or the excess plant rots. Either way, the CO2 is released again into the atmosphere, so there's no real change. However, what tends to get ripped out to make way for agriculture is forests and forests sequester CO2 in trees. There's good evidence that one of the causes of the little ice age was plague and other diseases. When millions of people were killed in the old and new worlds, a great deal of farmland reverted to forest. The drop in CO2 (and resultant drop in global temperatures) are clearly visible in the data.
ddaye
4.4 / 5 (10) Sep 06, 2018
Things are better now than ever before in history <= if you think this is bad, you are one miserable person.
The issue is the trend into the future.
zz5555
4.6 / 5 (11) Sep 06, 2018
Things are better now than ever before in history <= if you think this is bad, you are one miserable person.
The issue is the trend into the future.

OCC doesn't think about how current changes will affect the future. S/he's just like the guy that jumped off the Empire State Building. When he passed the 50th floor he said, "Everything's great so far!" ;)
barakn
3.8 / 5 (10) Sep 06, 2018
What greenhouse gases, CO2? it rose 30%, nothing happened. And we don't have massive volcanoes spewing out S2O4 and raising the temp around them hundreds of degrees hotter like Venus.

You're in such denial about what's happening on your own planet that you are willing to lie about about another planet? Sad.
Old_C_Code
1.8 / 5 (10) Sep 06, 2018
CO2 has nothing to do with temperature increase. Man increased CO2, temp didn't follow.

Doesn't seem like a 30% rise in CO2 has done anything, this is just reality... sorry.
Old_C_Code
1.9 / 5 (9) Sep 06, 2018
barakn: You dope, I said no lies about Venus.
Old_C_Code
1.9 / 5 (9) Sep 06, 2018
The unaccomplished band of Chicken Little and his friends, you can see it in your writing style. As if you were told as children the sky was falling (global warming,Gore movie), now you continue the sham, refusing to ask what a 30% rise in CO2 actually does.
Solon
2.6 / 5 (8) Sep 06, 2018
".. the only explanation I could come up with is early agriculture, which put greenhouse gases into the atmosphere and that was the start of it all."

What percentage of the Earths land could these ancient farmers have covered with their agriculture? About .000001% at most I'd estimate, and that is enough to cause warming??
Thorium Boy
2 / 5 (8) Sep 07, 2018
Warmth = life. Cold = death, Proven on Earth many times over 300 million years.
aksdad
1.9 / 5 (9) Sep 07, 2018
The findings are based on a sophisticated climate model...

And that's all you need to know about how realistic the findings are. They're not. The "sophistication" of a climate model tells us nothing about how accurate it is, which is what really matters. No one has yet produced a computer-generated climate model that accurately mimics the global climate system because, as the IPCC put it in AR5 (2013):

Because knowledge of the climate system's past and current states is generally imperfect, as are the models that utilize this knowledge to produce a climate prediction, and because the climate system is inherently nonlinear and chaotic, predictability of the climate system is inherently limited

IPCC AR5 demonstrated how inaccurate the CMIP5 climate models are in this graph:

https://www.ipcc....S-14.jpg

They haven't improved.
Ojorf
3.5 / 5 (11) Sep 07, 2018
CO2 has nothing to do with temperature increase. Man increased CO2, temp didn't follow.

Doesn't seem like a 30% rise in CO2 has done anything, this is just reality... sorry.


Your thinking is sooo far removed from reality, it's absurd...fact. Sorry.
Old_C_Code
2 / 5 (8) Sep 07, 2018
Ojorf: 30% rise in CO2 is a basic fact with little to no impact, you are truly insane.
Ojorf
3.2 / 5 (9) Sep 07, 2018
At least I have my little pet to back me up.
It's a huge, truly insane and unbeatable monster called Tatwus.*

What do you have?

Sic 'em Tatwus, rip his arguments to shreds & pee on the wreckage.
Oh? No need?
Already done!

*Tested, Accepted & Thoroughly Well Understood Science".
Old_C_Code
2.3 / 5 (6) Sep 07, 2018
Ojrf: that wasn't funny, you suck at humor.
Ojorf
3 / 5 (8) Sep 07, 2018
It was the truth though.
Old_C_Code
2 / 5 (8) Sep 07, 2018
You can't answer the question: what has a 30% increase in CO2 done?

You just invent crappy humor.

The only answers you have is: what they think it's going to do. Which isn't reality.
Old_C_Code
2 / 5 (8) Sep 07, 2018
*Tested, Accepted & Thoroughly Well Understood Science".

LOL, not if it's climate science by children who've done nothing in their lives yet, but know-it-all.

You can't even say how a man made 30% increase in CO2 has effected the planet!
Well understood, lol.
barakn
5 / 5 (8) Sep 07, 2018
barakn: You dope, I said no lies about Venus. -OCC

Yes, you lied.
massive volcanoes spewing out S2O4 and raising the temp around them hundreds of degrees hotter like Venus. -OCC

Let's start with the fact that there's no such thing as an S2O4 molecule. There's an anion with that formula (plus a minus sign for the extra charge), but you'll generally find it with a cation, and it forms a solid salt, not a gas. There is no spectroscopic evidence for S2O4- in the Venusian atmosphere, nor is it a plausible intermediate in the sulfur reactions that are occurring there. https://www.resea...ress.pdf
snoosebaum
1.8 / 5 (5) Sep 07, 2018
''Holocene if not for human agriculture ''' what a joke , as if we know much about 'Holocene human agriculture ''

'' the only explanation I could come up '' , of course !
Old_C_Code
1.8 / 5 (5) Sep 07, 2018
S2O4 has a name, disulfur tetraoxide.... but your right, not much on Venus.
So you got one wrong and one right. I was thinking of sulfuric acid H2SO4, but Venus CO2 is 96% of the atmosphere. But the S2O4 molecule does exists.
barakn
3.9 / 5 (7) Sep 07, 2018
There's no such thing as disulfur tetraoxide. Just because you googled it and got results doesn't mean it's an actual chemical. If you look more closely at the results, you'll see that the references are almost universally in test or quiz questions or answers to aid chemistry students in figuring out nomenclature, i.e. how to read a chemical name and derive a formula or how to read a chemical formula and derive a name. The chemical doesn't actually have to exist in nature or the lab in order for a chemistry teaching assistant to invent its name and formula to use in a quiz.
Old_C_Code
2.6 / 5 (5) Sep 07, 2018
Wow barakn you are so amazing and smart!
Old_C_Code
1.8 / 5 (5) Sep 08, 2018
Anyway, answer how a 30% increase in CO2 has effected the planet?

No one's tried to answer that question.

It seems like a really important question, given the hysteria CO2 seems to cause people.
zz5555
3.9 / 5 (7) Sep 08, 2018
I don't think OCC is necessarily a liar. His comments have indicated that he's not very competent in areas like science, math, or logic. He seems to lack any of the curiosity that most people interested in science have. Look at his comments claiming that CO2 has no effect on temperature. It was trivially easy to show that current CO2 levels are well correlated with the temperature increase. The data even showed that the Increase in CO2 levels preceded the increase in temperature, indicating that it was the increase in CO2 that caused the increase in temperature.

So it's the increase in CO2 that has caused a temperature increase of ~1C, increased extreme weather, etc.
zz5555
4 / 5 (7) Sep 08, 2018
But OCC ignored that data that directly refutes his claims and then claimed that temperature increase always precedes CO2 increase. Even the least little bit of curiosity would show him that the current CO2 increase is not due to temperature. When temperature increase causes CO2 levels to increase, it's because the oceans have warmed enough to start giving off some of the CO2 in the oceans. That's why there's a lag of a few hundred years between the start of warming and the increase in CO2 when something else drives the warming. But the oceans are still becoming more acidic, which means they're still absorbing CO2. So the oceans haven't gotten warm enough to give off CO2 - yet. When they do we'll have have a positive feedback loop with the oceans releasing CO2, which causes more warming, which causes more CO2 to be released, etc. (It still won't be runaway warming like on Venus, though.)
Captain Stumpy
3.2 / 5 (5) Sep 08, 2018
@occ
answer how a 30% increase in CO2 has effected the planet?
http://iopscience.iop.org/article/10.1088/1748-9326/10/1/014005

http://science.sc...5515/270

http://www.woodfo...60/trend

https://scholar.g...mp;btnG=

About 383,000 results (0.03 sec)
Old_C_Code
1.7 / 5 (6) Sep 08, 2018
CaptnStinky: Those links show nothing! Global warming is a religion.
zz: Math? You dope, this has nothing to do with math, and I've taken plenty of calculus you moron. I used to do it for fun before I took the classes. What a stupid conclusion.

You have a religion, not a science. Dopes. Alter more data, you were already caught changing data.
Captain Stumpy
3.4 / 5 (5) Sep 08, 2018
@old cnut
Those links show nothing!
sorry you can't read then
try this first: www.readingbear.org

when you finish those courses, I'll provide you with more
Global warming is a religion
since when is direct observation and measurement religious?

What, exactly, constitutes "religion" in your illiterate delusional paid-for-trolling peanut-brain?

you asked, I provided evidence
not speculation, but validated evidence
(keyword = validated)
and I've taken plenty of calculus
doubtful, considering
Old_C_Code
1.8 / 5 (5) Sep 08, 2018
CaptnStinky: Those links show nothing! Your climate change hysteria is a religion.
zz: lol, Math? I've taken plenty of calculus, math has nothing to do with a CO2 rise helping Earth.

So zz at least you're honest, and admit the rise of CO2 has done nothing, yet. That's sorta nonsensical for the argument, as if we have to wait for the temp to kick off ocean CO2 output. A lag, you're nuts!
Old_C_Code
1.8 / 5 (5) Sep 08, 2018
CaptnStinky: You are a mainstream c***sucker, we all see that. Climate science is the only science subject off limits to debate, just like a religion.
Old_C_Code
1.8 / 5 (5) Sep 08, 2018
P.S. I have more successful products (107) in the field than you and all the people you know will ever have. I don't like bragging, but if you insist on those insults,then I've just got to let you know, I'm a winner, what are you?
Captain Stumpy
4 / 5 (4) Sep 08, 2018
@oldcnut
You are a mainstream c***sucker, we all see that
wrong again
I just choose to follow the evidence which happens to be what mainstream advocates
it's not everyone who can be a delusional paid-for trolling idiot like you
Climate science is the only science subject off limits to debate, just like a religion
debates are not off limits
however, your delusional side continually refuses to accept validated science

therefore it is the denier movement which is like a religion, not the climate scientists

this is demonstrated by you above in more than one way -
when you refuse to accept validated evidence and proven science to adhere to a belief then it's demonstrative of delusional behaviour and/or religious fanaticism
P.S. I have more successful products (107) in the field than you and all the people you know will ever have
rule 37
plus - bragging about delusions while not being able to validate them indicates mental instability
Captain Stumpy
4 / 5 (4) Sep 08, 2018
@cnut cont'd
I don't like bragging
hyperbole?
or just a lie?

given the above...
but if you insist on those insults
factual labels aren't insults
I can support every label I've ever assigned to you or anyone else and I am fully willing and able should you ever attempt defamation proceedings
then I've just got to let you know, I'm a winner, what are you?
really?
a "winner" would validate their claims with links, references and evidence

you know, like my posts above answering your question?

where is your refute to the 383,000 results?
The best you've produced above is "Those links show nothing! Your climate change hysteria is a religion"

considering the evidence above proves your statement is blatantly false, that makes you a liar, illiterate and a complete idiot

That isn't pejorative: it's factual
Old_C_Code
1 / 5 (5) Sep 08, 2018
CaptnStinky: I'm a paid-troll? God you are a stupid loser. No evidence of CO2 raising temp you idiot, 383,000 results lol, dope, learn how search works.
Old_C_Code
1 / 5 (5) Sep 08, 2018
CaptnStinky: I have to repeat, after re-reading your posts... God you are stupid.
Old_C_Code
1 / 5 (4) Sep 08, 2018
//====================================
extern int BankTheme_GameLoop(void)
{

if(!okcasino) { popup=0; Playing=0; return(1); }

if((!frscreen)&&(!bonus2)&&(!bonus3))
if(CheckWalkaway())
{
if(popup) { walkaway=0; popup=0; AddGameMice(); NextBackground(); }
else { Playing=0; return(1); }
}

goto FUStinky;
Captain Stumpy
2.3 / 5 (3) Sep 09, 2018
@old cnut
I'm a paid-troll?
you do this for free?
"God you are a stupid loser"
No evidence of CO2 raising temp you idiot
you mean other than experimental evidence that made predictions and then matched observation which prompted direct measurement in the atmosphere showing a cause which was then validated demonstrating that you "are a stupid loser", that is...

Of course, if you want to skip the bulk of the overwhelming evidence you can just re-read the studies referenced in the Lacis et al paper

(after you learn to read)

which then leads to- I have to repeat, after re-reading your posts... God you are stupid
GrahamKJ
4.3 / 5 (3) Sep 09, 2018
Given that the earth's population was probably in the order of less than 20 million in the period prior to 5000BC and that the tools the people had for agriculture were rudimentary (pre-bronze age) it is difficult to imagine that a very large area was needed for cultivation (and at this time probably most people were still hunter-gathers. While I understand that many early cultivation techniques involved slash and burn, the population would have been such that these areas would have become reforested as the people moved on (leading to a reduction in atmospheric carbon). I am speculating but would be interested in learning how the authors came to their conclusions.
antigoracle
1 / 5 (5) Sep 09, 2018
No evidence of CO2 raising temp you idiot
you mean other than experimental evidence that made predictions and then matched observation which prompted direct measurement in the atmosphere showing a cause which was then validated demonstrating that you "are a stupid loser",

Of course, if you want to skip the bulk of the overwhelming evidence you can just re-read the studies referenced in the Lacis et al paper.....HAWW..HEE...HAWW...HEE...


Stumpid the Chicken Little Jackass brays again.
This is the jackass who has boasted about his jaunt to NYC, spewing CO2 all the way, just so to get a sniff of the methane from his False "Profit", Al Gore's rectum and pretend to care by protesting. Yep, this jackass can read, knows the science and yet is blind to his own hypocrisy. This is the jackass who'll save the world by braying at the heretics.
Please, Jackass Stumpid, find us a single peer reviewed study that conclusively shows Globull Warming is caused by man.
Captain Stumpy
4 / 5 (4) Sep 09, 2018
@anti-cnut the liar
... who has boasted about his jaunt to NYC, spewing CO2 all the way
Nope

so much for your reading/comprehension
LMFAO
find us a single peer reviewed study that conclusively shows Globull Warming is caused by man
you illiterate paid-shill moronic idiot!
LOL

asked and answered with not only peer-reviewed studies "that conclusively" prove AGW, but validation to boot!

Ah, right!

yall can't read and as such you must then deny the existence of all the science because you can't read, for your lord and masters pay you well to deny

ROTFLMFAO

zz5555
5 / 5 (3) Sep 09, 2018
I am speculating but would be interested in learning how the authors came to their conclusions.

The DOI link at the end of the article links to the full paper, so that might help out. You might also be interested in Ruddiman's earlier papers that develop these theories. One of the first I'm aware of is: https://www.chris...2003.pdf . It's a long paper, so may give the most information.

The next paper I have (from 2011) attempts to show that the changes in CO2 & CH4 are anthropogenic: http://www.theori...iman.pdf .

The final paper (from 2014) quantifies how much warming was due to humans (https://monoskop....#page=38 ). It also has some discussion about where the agricultural regions were, so might be of interest to you. As you might note, I find this theory quite interesting.
snoosebaum
2.3 / 5 (3) Sep 09, 2018
zz from your link above
https://www.chris...2003.pdf

To evaluate the climatic impacts of these pre-industrial
greenhouse-gas increases, the following analysis uses the IPCC (2001) estimate of
a 2.5 ◦C equilibrium sensitivity of global climate to a CO2 doubling.
The Holocene increases of CH4 and CO2 were so gradual that the climate system
had ample time to come to thermal equilibrium with the radiative forcing.
The estimated early- anthropogenic CH4 increase of 250 ppb would have warmed
global climate by 0.25 ◦C, and the estimated 40-ppm CO2 increase would have
added another 0.55 ◦C, for a total warming of ∼0.8 ◦C by 1800 AD (Figure 8c). In
comparison, the industrial-era warming since 1850 has reached ∼0.6 ◦C, of which
∼0.45 ◦C is attributed to several anthropogenic impacts and the rest to solar and
volcanic variability (Wigley et al., 1998).

notice how data follows from theory not the reverse
TorbjornLarsson
5 / 5 (3) Sep 09, 2018
It is interesting that Rudimann's theory is strengthened for every test, indicating that it is robust. With > 3000 years of accumulated change it would amount to < 300 years with 1/10 the greenhouse gas releases. zz5555, thanks for the references!
TorbjornLarsson
4 / 5 (4) Sep 09, 2018
Wouldn't agriculture produce more plants capable of utilizing CO2 and producing oxygen?


"It seems that this perplexing result may be because as time went by, less nitrogen was available to fertilise growth of plants in the C3 plots and more in the C4 plots. So the effect was not just due to the plants themselves but also to their interactions with the chemistry of the soil and its microbes.

These results suggest that the way that changes in CO₂ affect established ecosystems are likely to be complex and hard to predict. They may hint that, as CO₂ in the atmosphere increases, C4 tropical grasslands could perhaps absorb more carbon than expected, and forests, which are predominantly C3, might absorb less. But the exact picture is likely to depend on local conditions."

https://phys.org/...html#jCp
TorbjornLarsson
4.2 / 5 (5) Sep 09, 2018
Global warming is a religion.

"Certain human activities have been identified as primary causes of ongoing climate change, often referred to as global warming. ... Scientists actively work to understand past and future climate by using observations and theoretical models."
https://en.wikipe...e_change

notice how data follows from theory not the reverse


The analysis follows the data obviously. But what would be the problem with understanding the process by using theory? The Early Anthropogenic Hypothesis describes a weak signal, which is why they have to use another MIS as reference.

But as far as modern AGW, you can "sleep well" now, since I hear the warning trend signal is so strong that it suffices to make a spreadsheet correlation analysis on the data alone. The old chestnut that you needed climate models to see the warning and humans as main factor seems outdated.
zz5555
3.7 / 5 (3) Sep 09, 2018
notice how data follows from theory not the reverse

Are you saying that you think that data can't come from a theory or that theory can't come from data? Obviously, theory can come from data: oftentimes new theories are developed because old theories can't explain data. And just as obviously, data can come from theory: we use relativity for GPS calculations every day. All you need is a well established theory. No one reasonably denies that the greenhouse gas theory is well established - it's currently only opposed on political or philosophical grounds. Because of uncertainties in feedbacks, there remains uncertainty in warming values, but no one credibly denies that increasing greenhouse gas levels increases global temperatures. (But an ECS value of 2.5 is likely low - the data indicates that the most likely value is ~3.)

But maybe I'm missing your point.
snoosebaum
2 / 5 (4) Sep 09, 2018
'' but no one credibly denies that increasing greenhouse gas levels increases global temperatures.''

no one in the echo chamber, Rudimans paper just seems like its trying to prove a current fashion. What about huge unknowables like wildfires ?
Old_C_Code
1 / 5 (3) Sep 09, 2018
losebaum says: '' but no one credibly denies that increasing greenhouse gas levels increases global temperatures.''

Oh BS,plenty of scientists question this, where is the evidence?
No evidence CO2 has increased temperature, just pretend because you think so.
Credibly denies, yes... SHOW THE EVIDENCE, you f***ing can't.
zz5555
3.7 / 5 (3) Sep 09, 2018
no one in the echo chamber, Rudimans paper just seems like its trying to prove a current fashion. What about huge unknowables like wildfires ?

That would be interesting. If you look at Fig. 2c from that paper, you'll notice that the CO2 levels depart from the curve found in previous interglacials. This means that there was something different about this interglacial. Wildfires (other than those started by humans) would have been around in the previous interglacials, so that's unlikely to be the issue. In fact, all natural causes would have been around in previous interglacials, so the cause is almost certainly not natural.

It's definitely a fact that agriculture will cause CO2 levels to rise, so you would expect there to be some rise. That the rise coincides with the rise of human agriculture makes it very likely that humans are the cause. By the way, the 2011 paper goes into this in more detail.
Ghostt
3 / 5 (2) Sep 09, 2018
And now human's effects on the planet's climate are accelerating into an extreme that humans may not be able to survive. We better stop emitting greenhouse gases, and quickly figure out how to reduce the concentrations we've already emitted. We are not trying to save the planet, we are trying to save ourselves.


Humans will survive it. Just badly, uncomfortably, and with much suffering.
zz5555
3.7 / 5 (3) Sep 09, 2018
no one in the echo chamber, Rudimans paper just seems like its trying to prove a current fashion

No one outside of the "echo chamber" credibly denies that increasing greenhouse gas levels increases global temperatures either. Seriously, the greenhouse gas effect is basic physics - and not very complicated physics either. You can argue about how much temperature rise will occur (but even that's difficult any more), but you can't argue that GHGs don't affect temperature and not look like an idiot. There's just way too much science and data to do that.

As for Ruddiman trying to prove a "current fashion", AFAIK Ruddiman was the first with the hypothesis so if there's a fashion, he created it. I'm not sure where the idea comes from that more data supporting a theory somehow weakens that theory.
snoosebaum
2.3 / 5 (3) Sep 09, 2018
'' the greenhouse gas effect is basic physics ''

yes of course there is some physics involved how could there not , what is in dispute , is it meaningfull ?
zz5555
3.7 / 5 (3) Sep 09, 2018
yes of course there is some physics involved how could there not , what is in dispute , is it meaningfull ?

Meaningful in what way? That the warming will be significant? That seems to be you moving the goalposts. First, you claimed that it was possible to dispute that there would be warming. Now you seemed to have moved on to "the warming isn't significant". Unfortunately, all data indicates that the warming is significant and damaging. At this point, I think the question is: How damaging? At this point, I think the data clearly shows that the damage is significant now and will only get worse. But this is a point that can be argued, albeit with difficulty.

By the way, take a look at those opposing the science. From a scientist's viewpoint, their arguments tend to be laughable. Rarely, there'll be an interesting argument that warrants closer examination, but nothing comes close to drastically changing the science.
snoosebaum
2.3 / 5 (3) Sep 09, 2018
what a joke
Old_C_Code
1 / 5 (4) Sep 09, 2018
The Earth has a natural climate regulator; clouds and storms. This isn't simulated (too complex).

Surely it's not warming to the doom & gloom levels the meatheads think, and immediate action is NOT necessary.

And a 30% rise in CO2 hasn't done anything bad. Maybe the Earth's climate regulation took care of it.

P.S. I'm an atheist. And climate science is like a religion.
zz5555
3.7 / 5 (3) Sep 09, 2018
what a joke

Always the favorite reply by those with no science or data to back them up. As I said, the science isn't that difficult. Rejecting science just because of your political or philosophical bent makes no sense to me.
Captain Stumpy
3.7 / 5 (3) Sep 09, 2018
@koch-c-cnut
And a 30% rise in CO2 hasn't done anything bad. Maybe the Earth's climate regulation took care of it
Lacis et al
P.S. I'm an atheist
irrelevant
And climate science is like a religion
then why do they allow for peer-reviewed journal studies?

this is where your argument falls flat

not one denier fanatic like yourself has managed to refute any of the validated links I've provided to you (let alone any others)

therefore it can be shown that you're arguments against the science are *literally* a religion in that your belief against AGW is all based entirely upon your faith that it's not real

Physics says it's real
thermodynamics says it's real
hydraulics says it's real

koch et al?
Hmmm... and why, exactly, would they deny it?
I wonder...
http://www.drexel...nge.ashx
Ojorf
2.7 / 5 (7) Sep 10, 2018
The Earth has a natural climate regulator; clouds and storms. This isn't simulated (too complex).

Surely it's not warming to the doom & gloom levels the meatheads think, and immediate action is NOT necessary.

And a 30% rise in CO2 hasn't done anything bad. Maybe the Earth's climate regulation took care of it.

P.S. I'm an atheist. And climate science is like a religion.


Your stupid beliefs are a religion to you. Science is based on observation, your beliefs are based on stupidity and denial. Hardly comparable.
Old_C_Code
1 / 5 (3) Sep 10, 2018
hydraulics says it's real? God you are stupid.

I'm an atheist, show me the observations CO2 has done anything?
You clown.
Old_C_Code
1 / 5 (3) Sep 10, 2018
zz says : "Unfortunately, all data indicates that the warming is significant and damaging. "

This is coming from a doom and gloom turd brain, with no real data to back the claim, other than we are in a warm period (true). And we're lucky, past history shows another ice age coming.
Ojorf
3 / 5 (6) Sep 10, 2018
hydraulics says it's real? God you are stupid.

I'm an atheist, show me the observations CO2 has done anything?
You clown.


Open your eyes you loon, it has been explained to you over and over. You have commented on multiple articles that have demonstrated it, your mind must be going if you can't remember it.
antigoracle
1 / 5 (3) Sep 10, 2018
not one denier fanatic like yourself has managed to ....HAWW..HEE...HAWW...HEE...

LMAO.
The Stumpid jackass HAWW..HEES..again.
Not one of those links conclusively shows that globull warming is manmade.
Hey Stumpid perhaps the answer is here -- http://hockeyscht...-26.html
Joker23
1 / 5 (5) Sep 10, 2018
Nonsense. The World Population is estiimated to be 7 Billion today. It was estimated to be 1 to 2 billion 4 millennia ago. How exactly did they manage to accomplish climate change? No SUV's Not power plants,about 1/3 the current population.........really?
zz5555
5 / 5 (4) Sep 10, 2018
Nonsense. The World Population is estiimated to be 7 Billion today. It was estimated to be 1 to 2 billion 4 millennia ago. How exactly did they manage to accomplish climate change? No SUV's Not power plants,about 1/3 the current population.........really?

Did you ever think of, I don't know, reading the article?
zz5555
5 / 5 (4) Sep 10, 2018
The Earth has a natural climate regulator; clouds and storms.

Since the earth is an isolated body, the climate can only gain or lose heat through radiation to or from space (there's some coming from the ground, but it's very small compared to other sources). So the 2 primary regulators are albedo and GHGs. Clouds can affect albedo by reflecting sunlight, but they also work as "insulators" as anyone who lives in colder climates knows (cloudy nights are warmer than clear ones). Unfortunately for those hoping clouds will help regulate things, observations show that clouds provide a positive feedback (ie, they help to warm things). Still, it's nice to see OCC admit that GHGs affect the climate.

Storms can't really affect how much energy is radiated except inasmuch bigger storms cause more cloudiness. Is this part of OCC's "CO2 hasn't done anything bad"? Bigger storms are better? Strange argument.
Captain Stumpy
5 / 5 (3) Sep 10, 2018
@old-Koch-Cnut
hydraulics says it's real? God you are stupid
yeah, because no sensible scientist would ever use hydraulics studying oceans
that would be downright crazy, eh?
I'm an atheist, show me the observations CO2 has done anything?
you're an illiterate and I've already linked plenty of evidence proving CO2 has "done anything"

just because you refuse to read it doesn't mean it aint there, real, or proving you to be a moron
ot one of those links conclusively shows
I guess you can't read then...
oh wait! You're a sock anyway, so you're just trying to bolster your own delusional socks with repetitious idiocy and delusional denial
antigoracle
1 / 5 (3) Sep 10, 2018
@I guess you can't read then...HAWW....HEE...HAWW...HEEE

The Stumpid jackass brays yet again.
This jackass is so illiterate he post links that are hidden behind a pay walls.
Have a gander at, peer reviewed, AGW Cult "science" -- http://hockeyscht...-26.html
hat1208
3.4 / 5 (5) Sep 11, 2018
Guess who's sock Old Cnut is? Any takers?
zz5555
5 / 5 (2) Sep 11, 2018
There's a lot of similarity between OCC and benni. Claims he has ability in some introductory college subject (Diff Eq or calculus) and claims some special occupation (nuclear eng or programming). Though why he might have chosen programming, I can't understand. Even complex programming tasks are much easier than science or nuclear/electrical engineering. They both ignore science and observations in their rants. OCC seems to rant on different topics, but a troll wouldn't care what topics he ranted about, just as long as they could annoy people. And I've always assumed that benni was a troll, so that might make sense. Come to think of it, I don't recall seeing a benni rant for a while. Was he banned?
howhot3
5 / 5 (1) Sep 11, 2018
There are a couple of men that know how to code 8-bit, but real men program in z80 in HEX from memory. I don't think old C code gets the stuff. I think he's an old right-wing crotchety sob that can't think for himself and just listen to Fox News all day. Science is meaningless to these flakes and nuts. We see so many of these anti-science climate-denying flakes and nuts. They don't deserve your respect or admiration, they are nasty people with an agenda.,

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