I really don't want to live in the Middle Ages whenever the sun goes down, and I really don't think you want to, either. People who went for late-night walks in cities in the Middle Ages ended up stabbed for their coin purses since the lack of lighting meant the criminals could get away scot-free, and I don't see how it would be any different in today's cities unless like back then, people started carrying weaponry while active during the night hours.

This is an interesting article:

http://www.pnas.org/content/early/2009/12/24/0902323106.full.pdf

Maybe we've got more to worry about than we think ??

Well at least it shows that it's quite a challenge to reconstruct ancient atmospheric CO2 concentrations.

I give those researchers my R.E.S.P.E.C.T.

Loved the opening sentence (forgive the PDF copy/paste formatting issues):

The references are, of course, to IPCC 4.  2007.  I think that's the one in which the claim of Himalayan glacier retreat was based on an article from a travel magazine, but I could be wrong - coulda been IPCC 5 or 3 or...

What was interesting to me was the number of times these phrases and words appeared:

"thought to be"

"considered to be"

"probably"

"supports the idea"

"best estimate"

"suggesting"

"may"

Then there's this:

Followed by this:

Translation: The numbers are all over the effing place but if we use a number that we like, our best estimate is we can support the idea of suggesting that we may probably be fucked sooner than even the IPCC thinks.

And they call that science, folks.

Has there ever been an example in the past where CO2 rising preceded an increase in temperature?  It seems like before we start yelling about CO2 being a threat (it's what? 0.4% of the atmosphere) that we would have examples of thus. But we don't. CO2 always goes up after temperatures go up.

The single biggest problem with AGW is that there is zero evidence to support CO2 as the culprit.  If you wanted to blame humans for climate change I'd look at the combined urban heat sink affect, mass agriculture, deforestation. 

I always enjoy seeing lay people appeal to authority on this issue. As if the AGW hypothesis is somehow really complex. Sure plenty of people can grasp quantum mechanics and string theory but climate change? Oh no, we aren't sophisticated enough.   AGW lives and dies based on proving that higher CO2 levels result in measurable differences in global temperature. That's a very simple, testable hypothesis and it fails.

You drew the correct (and most kind) conclusion, Geo:

Yes....that's a chicken and egg situation....which comes first...;)

Not really. Temperatures always go up first. That's the big problem with the CO2 AGW hypothesis.

Positive feedback loops...

Since clear evidence now shows there is no connection between temperature mounting and CO2 levels such a feedback loop doesn't exist.

It isn't possible to have reliable data from prior episodes. As you know, during prior episodes of GW, the science and means of accurate observation simply weren't around. That does not disprove what is to most, clear. CO2 isn't the only greenhouse gas. Attributing all heating to it alone is incorrect. However, as more and more hydrocarbons are burned, more enters the atmosphere. The largest contributor is water vapor as it holds the intrinsic heat of vaporization. For every one carbon atom, there are several H atoms, thus for every one CO2, there are many more H2O molecules.

To me, it seems obvious that just as man is influenced by his environment, he influences it. It may well be that we are in a cyclical warming trend, but that does not mean that we should not alleviate as much as possible our acceleration of it just as we should control other forms of pollution.

Did we read the same article ???

The authors noticed a large discrepancy between paleosol CO2 estimates and those from other sources.

I've actually downloaded some of those data sets and I've taken a look at the CO2 "measurements" and those show large discrepancies indeed.

So the authors decicded to review how CO2 values were estimated from the soils. And they discovered that one of the assumptions that was made about the carbonate precipitation was simply wrong.

The carbonates precipitate only in the warm dry season, not during the wetter season when they may dissolve.

As a result, it's not appropriate to use properties of the soils averaged over the whole year, but it's more appropriate to use the properties of the soil that occur during the dry season.

Then they show that this results in significantly lower CO2 estimates from the soils, and that those are in line with the estimates from other sources.

It's the improved understanding of the precipitation process that brings CO2 estimates "down". It's not some manipulation of the data.

And I had hoped for some respect for researchers. It was too much to hope for :) 

Actually it is nearly 100% correct. The other greenhouse gases (H2O, CH4) have very short lifespans and large quantities cannot survive in the atmosphere long enough to make a difference over thousands of years.

Water vapor (H2O) survives for some days, no more: then it returns to the surface as rain or snow. It is not driving temperature by itself.

CH4 survives for about 10 years, then it decays into CO2. To have long-lived effects, this greenhouse gas would require a continuous supply of very very large quantities of CH4. There is no known source of that magnitude.

Only CO2 survives for thousands of years, long enough the influence the climate on geological time scales. It doesn't rain down, it doesn't snow. It only settles slowly as carbonates on the sea floor or is buried slowly in peat wetlands.

H2O also acts as a greenhouse gas as you state, but "only" as a direct feedback mechanism, not on its own. And it's a very important feedback as well although I wouldn't go as far to say that CO2 is negligible... the articles I've read state that the relative contribution of CO2 to H2O is about 1:2.

http://www.realclimate.org/index.php/archives/2005/04/water-vapour-feedback-or-forcing/

Well it doesn't...

1. we observe it right now.

2. if you want to now about the link of CO2/temperature even during ice ages, read these things:

http://www.bitsofscience.org/ice-age-co2-ocean-3569/

http://www.sciencedaily.com/releases/2012/03/120329142020.htm

http://www.nature.com/nature/journal/v484/n7392/full/nature10915.html

3. Ice-core data. Even in its rawest form, ice-core CO2/T data show a very very good correlation - and whether T comes first or not doesn't matter, what matters is that T never rises independently of CO2 - and that means that T depends on CO2. If CO2 wouldn't have any influence on temperature, then the T and CO2 wouldn't have such a close correlation.

Actually there is evidence.

For example extinction events are preceded by large increases in CO2... and then extinction.

And the absence of ice-sheets during much of earth's history when CO2 levels were higher. And the absence of any ice during times of highly elevated CO2.

What other explanation can you think of?

Actually it doesn't fail. There are several observations that support it, even today.

- Stratospheric cooling: http://www.atmosphere.mpg.de/enid/20c.html

- Increasing heat content of the oceans: http://www.realclimate.org/index.php/archives/2013/09/what-ocean-heating-reveals-about-global-warming/

- change in vegetation on long (30 year) time scale.

http://www.dailymail.co.uk/sciencetech/article-2291482/How-Northern-hemisphere-greener-Nasa-reveals-shocking-30-year-study-showing-Earths-seasons-changing.html

- increased melting of permanent ice-sheets (Greenland, Antarctica) and of glaciers.

http://thinkprogress.org/climate/2012/11/30/1260591/science-stunner-greenland-ice-melt-up-nearly-five-fold-since-mid-1990s-antarticas-ice-loss-up-50-in-past-decade/

http://environment.nationalgeographic.com/environment/global-warming/big-thaw/

Well.. this may give a better overview than I can.

http://en.wikipedia.org/wiki/Effects_of_global_warming

Using wikipedia as a source of reliable information for anything is foolish.

Look GeomanNL, obviously you are addicted to this topic post. Nobody will change your mind on your GW beliefs as you won't change anyone else's mind that disagrees with you. This continued beating of a dead horse only feeds your addiction.

^ 

Well... what can I say, some people are just playing stubborn.

It's just that, the article I found was a bit disturbing.

If ancient hot climates where "hot" at levels of 1,000 ppm CO2 giving minor extinction events, and if major extinction events would already occur at say 2,000 ppm CO2, then we're in a much worse situation than I thought earlier.

In some cities, they give heroin addicts clean needles, knowing it is a lost cause to break their addiction...

We seem to have adopted a similar solution...

Well... yes I should stop, I cannot change the world anyway. Perhaps today's the day.

You don't really need to stop commenting but perhaps one where you don't continually try to change what others believe. They have a right to their own opinion as you do.

Yeah whatever. I think it's up to the next generation, this one is too much in the grip of power money and the desire for luxury.

I'm enjoying this life too while I can. Fuck the world! All power to the individual.

But what I think is really surprising here, is the general mistrust in science and scientists.

Where does that come from?

The Dutch are indoctrinated from birth with this stuff, it's stronger then themselves. At schools WWF is the main source of information and anyone who dares challenge the "Mankind is the sourceof all evil" meme gets into trouble with their teachers. No joke.  Fortunately i'm Dutch from an earlier generation.

Except you, right?  You're being emminently reasonable and logical.  

This is the reason there's not much point discussing it with you.  You change whatever those who disagree with you say into these giant strawmen rather than actually addressing their points.  You take multi-paragraph, carefully crafted expressions of skepticism (or other reasons for not wanting to jump feet first into the AGW bus) and pretend that it all boils down to this so you don't have to actually address the concerns.  It's soapboxing, not discussion.  

I personally love the discussion with people who I disagree with (rather than everyone agreeing in an echo chamber) when it is approached in good faith and where the two sides try to understand the other's points and opinions.  This doesn't have to (and rarely does) result in changing of opinions. But it's an exercise that forces us to rethink what we believe and to make sure we understand our own thoughts and opinions as well as we think we do.  But that can't happen when everything one side says is trivialized into this:

You're too emotionally invested in being right to be thoughtfully invested in debate or discussion. 

Let me summarize school for you: Learn and forget!!

I have replied to lots of people in a fair amount of detail. And whenever I find other interesting things, I add it to this discussion.

And yes, it does boil down to that in one way or the other.

1. Someone reads one of the gazillions deniers-blogs and believes their shit and posts new blogs with new shit. Full of fancy graphics and nice fitting trends, while it's really based on hot air.

The sad thing about that is, that if you read enough of that crap, that you start to believe it. If you are faced with a hundred "convincing" arguments and you read all of those, then by sheer quantity they suddenly become "convincing" or at the very least you will not trust anything anymore. Even though every single one of those arguments is based on nothing. They exploit noise in the data. They take only those points from the data that benefit their viewpoint. They try to distract with competing mechanisms and try to show a nice fit to observations. They try to discredit all the good data, and to promote their own garbage. It's just too sad.

2. Someone doesn't care, just distrusts any authority and thinks "scientists" are just another form of authority that's not to be trusted, while they're really just nice people who just do their job and don't care about anything.

3. Or they are confused by one scientists (paid by a global corp) fighting another scientists (paid by non-profit government or whatever). They don't know who's right and who's wrong, they're both scientists right? Except that one of them is paid millions for their ridiculous ranting, while the other freezes his ass of in some remote glacier collecting data for a small salary.

And the REAL shame about this is, that once trust is lost, it is very hard to gain it back.

To the benefit of big old oil companies and lobby groups and whatever.

4. Observational science is one of the hardest there is. It is hard to collect data, describe it and to deal with the noise in the observations.

And then there's people who criticize it based on ... whatever grounds they have.

I just think there's no RESPECT anymore for other people's work.

It's so sad.

Yep

Yes, useless facts are quickly forgotten, but indoctrination lasts a lifetime.