Global warming discussion III

[r-j]

Oh I remember it quite well.

And the theory of AGW has been rigorously verified and accepted by the scientific community.

We've already heard EVERYTHING you're likely to say.

Buckaroo

After I explained the mechanism proposed by Cohen et al, I plainly stated, in terms nobody could mistake.

The sad thing is how this is being used to say all climate predictions mean nothing, when in fact it is how science advances. Once you know your theory is wrong, you change it.

That is science. Not denial of what is being observed.

March 19 2013

It was the Cohen et al paper that started this theory denial nonsense. It continues to this day.

 

[r-j]

(Edit) It just struck me that a scientific Theory should be clearly defined and easily accessed. Or am I wrong? (/Edit)

It is easy to define, and I have posted multiple links to both the definition, as well as explanations of the theory.

Of course it should be easy to find. And explained.

 

[r-j]

In my impression you are discussing semantics.)

I'm not the one resorting to semantic games. When Cohen et al 2014 states "global warming theory does not", they mean exactly what they say.

And any climate researcher knows exactly what theory they are talking about.

 

[hgus]

I will use a crude model so lesser force will be ignored for the time being.

Do any one on this board question any of these points about earths energybalance:

1) Solar energy is the absolute most important factor for input of heat.

2) Greenhouse gasses effects how much heat radiates out to space again. More carbon dioxide will make more heat stay in the system. We now have levels of carbon dioxide that hat not been seen in millions of years. And increasing.

If whe can not agree on the basics. The odds that we will agree on anything is slim.

/I am very tired at the moment, any error is blamed on that fact.

 

[Reality Check]

When Cohen et al 2014 states.. .

When Cohen et al 2014 (PDF) actual states

While global warming theory is consistent with record warm temperatures and more intense precipitation events, it does not directly explain cold extremes.

They mean that the theory that global temperatures are increasing says that global temperatures will warm eek and precipitation increase but does not directly explain cold extremes, r-j

Any climate researcher and anyone who can understand English knows exactly what theory they are talking about - the theory that global temperatures are increasing.

 

[Reality Check]

1) Solar energy is the absolute most important factor for input of heat.

2) Greenhouse gasses effects how much heat radiates out to space again. More carbon dioxide will make more heat stay in the system. We now have levels of carbon dioxide that hat not been seen in millions of years. And increasing.

One nitpick - the levels of CO2 have been as high or higher in the past: Measuring ancient-Earth carbon dioxide concentration

But other than that I do not question that the evidence is overwhelming that current global warming is primarily driven by the increase in CO2.

 

[RedPillNeo]

the levels of CO2 have been as high or higher in the past:

One thing I've seen mentioned in global warming discussions is, higher CO2 concentrations lag historical increases in temperature from various causes. In other words, temperatures rise to a much higher equilibrium, THEN CO2 concentrations continue to increase for a long period, extending the warm period. Perhaps this is due to carbon stores being released from permafrost, methane clathrates, peat bogs etc.

In the case of AGW, humans are increasing the CO2 concentration first, driving the warming, which is triggering the above sources to release MORE CO2 in a positive feedback loop.

I think that this could make AGW cause a faster warming than most of the warming events in geological history.

 

[macdoc]

It already has.."unprecedented" RATE of change crops up in overviews on the last century.
What you cover off is the dual nature of CO2 influence.
Most often in history CO2 has been a feedback from the influence of another driver - most often orbital positioning.

In our case it is both a feedback AND the primary driver of change as we mine and release into the atmosphere sequestered carbon by burning fossil fuels.

Common Climate Misconceptions
CO2 as a Feedback and Forcing in the Climate System
Zeke Hausfather — October 25, 2007

A fundamental misconception about the role that carbon dioxide plays in glacial transitions has helped fuel the argument that the lag time between temperature and CO2 in the paleoclimate record casts doubt on carbon dioxide as an important greenhouse gas.
It’s crucial that media reporting on climate change understand an important distinction between the dual roles of greenhouse gases as both forcings and feedbacks.

http://www.yaleclimateconnections.o...a-feedback-and-forcing-in-the-climate-system/

 

[macdoc]

Originally Posted by DC View Post
what do you guys and ladies think about ditching the 2°goal?

http://www.livescience.com/48097-cli...rees-goal.html
I doubt we are going to achieve only a two degree increase but should that stop us trying? If there were something else on the horizon that was going to cause so many problems and loss of life wouldn't we be working together to find a solution? From what I understand we will likely see an increase of 4 degrees by 2070. I fear for my grandchildren.

I really have doubts as well. It is very likely we a experiencing a second round of global dimming with aerosols offsetting some of the GHG warming.

Aerosols both human ( Asian Brown Cloud ) and volcanic

Volcanoes contribute to recent global warming 'hiatus'
Date:
February 24, 2014
Source:
DOE/Lawrence Livermore National Laboratory
Summary:
Volcanic eruptions in the early part of the 21st century have cooled the planet, according to a new study. This cooling partly offset the warming produced by greenhouse gases.

http://www.sciencedaily.com/releases/2014/02/140224133137.htm

This is a good explanation of the aerosol uncertainty.

What did the IPCC say about aerosols?

Aerosols dominate the uncertainty in the total anthropogenic radiative forcing. A complete understanding of past and future climate change requires a thorough assessment of aerosol-cloud-radiation interactions.

This is one of the conclusions about aerosols and their impact on our climate from the the final report from the Intergovernmental Panel on Climate Change (IPCC) on the physical science basis that was released recently. What brought them to this conclusion and what does it mean? In this piece, I’ll go through the headline statements and findings.

The IPCC are concerned with assessing how various factors affect the Earth’s climate and it dedicates an entire chapter to aerosols and clouds, which is accessible here.

How do aerosols impact our climate?

Aerosols, can broadly influence the climate in two ways; aerosol-radiation interactions and aerosol-cloud interactions. The IPCC included some nice diagrams of how these processes occur, which I’ve included below.

We are on a balance beam in the atmospheruc experiment with one anthro influence offsetting another.

When emerging economies start cleaning up their SO2 as first world did in the 70s .....look out....the warming acceleration 90s repeated but with even greater CO2 concentrations.

Interesting times

 

[Pixel42]

One thing I've seen mentioned in global warming discussions is, higher CO2 concentrations lag historical increases in temperature from various causes. In other words, temperatures rise to a much higher equilibrium, THEN CO2 concentrations continue to increase for a long period, extending the warm period. Perhaps this is due to carbon stores being released from permafrost, methane clathrates, peat bogs etc.

And the oceans. CO2 is water soluble, and cold water holds more than warm. As temperatures rise the oceans warm and release some of their dissolved CO2, as they fall the oceans cool and absorb it again, but there's a lag. It typically takes several centuries for the oceans to switch from being a net source of CO2 to a net sink when temperatures start to drop, and vice versa.

Atmospheric samples trapped in ice cores tell us that atmospheric CO2 goes from about 200ppm during periods of glaciation to about 300 ppm at the peak of an interglacial.

ETA: Incidentally nearly half of the CO2 we've put into the atmosphere has been absorbed by the oceans. This is causing its own problems:

http://en.m.wikipedia.org/wiki/Ocean_acidification

 

[DC]

Re DC's question (the Quote function is misbehaving for me), I think that when talking to politicians it's necessary to "keep it simple, stupid". A single number, preferably integer, is something they can grasp. A raft of "critical indicators" or whatever is something they can exploit for purposes of obfuscation and FUD, for both personal and public comfort.

Stick with the single number. Unachievable it may be (in practical terms; it could be done but ain't gonna be) but at least it's something that can be clearly unachieved.

my problem with the 2°C is that it ignores the largest heat uptakes, the oceans.
i would also like to keep a single number, but that single number should include lower tropospheric temperature and ocean temperatures. or heat content of both. amd , maybe also include ice mass.
but only looking at the atmosphere leads to the confusion like we have with the hiatus, where many people believe its not as bad as we thaught it would. but actually in that time period of the hiatus, we still had alot of energy accumulating in the climate system. and that is all ignored with only looking at the atmosphere.

 

[Kestrel]

Using the term hiatus is misleading. The heating effect caused by the increase in CO2 continues, getting a bit stronger every year. But in some years the effect may be masked by cooling linked to events such as the El Niño cycle or volcanic eruptions.

 

[DC]

Using the term hiatus is misleading. The heating effect caused by the increase in CO2 continues, getting a bit stronger every year. But in some years the effect may be masked by cooling linked to events such as the El Niño cycle or volcanic eruptions.

it is the term i read most in the scientific literature and i think everyone with the exception of deniers and trolls will understand perfectly well what is meant and i expecially pointed out that during that time there still was warming.

 

[DC]

When Cohen et al 2014 (PDF) actual states

They mean that the theory that global temperatures are increasing says that global temperatures will warm eek and precipitation increase but does not directly explain cold extremes, r-j

Any climate researcher and anyone who can understand English knows exactly what theory they are talking about - the theory that global temperatures are increasing.

why do you keep feeding a troll?
especially when he is right.

that the gobal average temperature is increasing is not a theory, that is an observation, a fact, and the theory, which i call AGW theory, is the explanation for this observation.
yes it is somewhat not really a own theory, it is more like a logical conclusion of the Greenhouse effect.
but i think that is exactly what they are refering to in the paper and other papers.

when he first started trolling around about it, half of the posters knew what he meant with global warming theory, and explained AGW to him, that should have been enough, but then the stupid argument started about this and is ongoing since months.

and the sad thing is, he is right about it. and some are just not able to admit an error and search for excuses and quible about semantics, which is exactly what the goal was of the trolling.

 

[greybeard]

Scientists find human fingerprints all over Australia's hottest year on record.

We started off with a heat wave that made January 2013 the hottest month on record that was part of the hottest summer on record that then became the hottest year on record.

Meteorologists and climatologists looking at records tend to express things by “anomalies” – how far above or below the long-term average is a particular temperature.

September 2013 had all the anomalous bells and whistles you could muster, managing to break above the long term average by 2.75C – a departure greater than any other month on record going back to 1910.

Instead of focusing on blame, it is more useful to understand the contributing factors to an event, such as natural variability and greenhouse warming. In the case of Australia’s record hot year, anthropogenic influences were a big contributor, to the point that the temperatures we experienced would have been virtually impossible without greenhouse gases. This doesn’t mean that natural variability isn’t important too.

There is one line of thought that all the weather and climate events we have experienced have occurred in a hotter, wetter environment caused by greenhouse gases. Because of this, we play a part in everything.

Another is the old stock statement that because many factors interact in complex systems, we can’t separate out human influences from natural climate variability.

I don’t think either is particularly useful for helping to understand the extremes we are experiencing.

Statements like “no single event can be blamed on global warming” aren’t useful. They prevent us from understanding how climate change is influencing what we experience.

Freeman Dyson said he has seen the warming for himself first hand in Greenland and the locals love it. Pity he is not a bit more widely travelled. Perhaps it's time to start buying property in Greenland though for when other areas have to be abandoned?

 

[DC]

Scientists find human fingerprints all over Australia's hottest year on record.





Freeman Dyson said he has seen global warming for himself first hand in Greenland and the locals love it. Pity he is not a bit more widely travelled. Perhaps it's time to start buying property in Greenland though for when other areas have to be abandoned?

strange article.
atrribution studies are seen as blaming Humans by many people because they find Human contribution to dominate.

and also this one
"the temperatures we experienced would have been virtually impossible without greenhouse gases."

virtually? i would say they are physically impossible without greenhouse gasses. sure he probably meant increased greehouse gas concentrations.
such strange phrases are also not helpfull at all.

 

[bit_pattern]

Freeman Dyson said he has seen global warming for himself first hand in Greenland and the locals love it.

I bet you he hasn't

http://www.grida.no/publications/et/ep2/page/2501.aspx

 

[macdoc]

Using the term hiatus is misleading. The heating effect caused by the increase in CO2 continues, getting a bit stronger every year. But in some years the effect may be masked by cooling linked to events such as the El Niño cycle or volcanic eruptions.

Not quite.You are equating two different phenomena
Aerosol based cooling ( global dimming ) is a outside the box driver - it reduces solar radiation so can completely offset GHG as Pinatubo records show.

ENSO etc just move heat around in the box, which may cause regional cooling but does not effect the continual GHG heat increase globally.
Burying heat in the ocean as La Nina does or releasing it from the ocean as El Nino does - does not vary the total radiative balance but it has dramatic regional climate impacts.

Aerosol is being proposed as a geo-engineering solution as it blocks incoming SW ....

Very important differences. Hope that's clear enough - typing one handed

 

[Red Baron Farms]

Freeman Dyson said he has seen the warming for himself first hand in Greenland and the locals love it.

He has also publicly stated he has taken a devils advocate position on purpose, that actually he isn't that well versed in climate science. Worked with it a few years, got bored, went on to other things.

Basically he says things to stir the pot. Open up new ways of looking at the issue. But I wouldn't say that he in any way disproves AGW. Contrarywise, Dyson himself, devils advocate on the issue though he may be, is still not a denier. He knows damn well manmade climate change is real. But you can't just automatically assume change equals bad in every case. I am fairly convinced it won't be good for me here in OK. Hot enough as it is. But you just can't assume it. Need to dig deeper.

 

[greybeard]

strange article.
atrribution studies are seen as blaming Humans by many people because they find Human contribution to dominate.

and also this one
"the temperatures we experienced would have been virtually impossible without greenhouse gases."

virtually? i would say they are physically impossible without greenhouse gasses. sure he probably meant increased greehouse gas concentrations.
such strange phrases are also not helpfull at all.

I think given the context we can take that as a given.