Hey! Two Cold Wars in one lifetime, how lucky can a generation get?

[superluser]

Do the natural causes they've accounted for include the warming up of the sun?

Yes.  Solar and volcanic activity are specifically included under natural causes.

There is a little bit of an issue in these studies where CO2 is listed under anthropogenic causes, but I don't see CO2 listed under natural causes.

That issue, however, is easily dealt with.

Since 1751, roughly 315 petagrams of carbon have been sent into the atmosphere by fossil fuel consumption.  That's 43% of the 730 Pg C in the atmosphere[1].

[1] Carbon in the Atmosphere and Terrestrial Biosphere in the 21st Century.  Yadvinder Malhi.  Philosophical Transactions: Mathematical, Physical and Engineering Sciences, Vol. 360, No. 1801, Astronomy and Earth Science. (Dec. 15, 2002), pp. 2925-2945.

[llearch n'n'daCorna]

... assuming none of it has been absorbed by growth, the oceanic sink, or elsewhere in the biosphere.

The first and third are unlikely, but i understand the second is a fairly big number.

[Valynth]

... assuming none of it has been absorbed by growth, the oceanic sink, or elsewhere in the biosphere.

The first and third are unlikely, but i understand the second is a fairly big number.

And then you have to take in to consideration that there are HUGE amounts of plants and algae in the oceans that consume a large amount of CO2.

I'd also like the naturalists to explain how earth has gone through ice ages and desert ages before humans even appeared.

[Reese Tora]

Do the natural causes they've accounted for include the warming up of the sun?

Yes.  Solar and volcanic activity are specifically included under natural causes.

There is a little bit of an issue in these studies where CO2 is listed under anthropogenic causes, but I don't see CO2 listed under natural causes.

That issue, however, is easily dealt with.

Since 1751, roughly 315 petagrams of carbon have been sent into the atmosphere by fossil fuel consumption.  That's 43% of the 730 Pg C in the atmosphere[1].

[1] Carbon in the Atmosphere and Terrestrial Biosphere in the 21st Century.  Yadvinder Malhi.  Philosophical Transactions: Mathematical, Physical and Engineering Sciences, Vol. 360, No. 1801, Astronomy and Earth Science. (Dec. 15, 2002), pp. 2925-2945.

Rather than how the amount introduced by humans in the last 256 years(hey, 2^8, neat!) that compares to the current level of carbon, I'd like to see comparisons of cabon introduced by humans to carbon introduced by other sources and an analysis on carbon introduction and carbon removal.

I could say that I've purchased five shirts in the last ten years, and that accounts for 50% of the shirts in my closet.  This does not account for how quickly my shirts become unwearable, how many shirts I owned before that time, or how often I recieve shirts from sources other than purchases made by me.  It's all factual, but, by itself, it doesn't give a clear picture on how much my own purchases affect my wardrobe. (and, no, I don't really know how many shirts I've bought or how many I have in wearable condition. )

[superluser]

... assuming none of it has been absorbed by growth, the oceanic sink, or elsewhere in the biosphere.

The first and third are unlikely, but i understand the second is a fairly big number.

According to the same source, the oceans absorb 2.1 Pg C/yr.

Rather than how the amount introduced by humans in the last 256 years(hey, 2^8, neat!) that compares to the current level of carbon, I'd like to see comparisons of cabon introduced by humans to carbon introduced by other sources and an analysis on carbon introduction and carbon removal.

The greenhouse effect is caused by how much carbon is in the air now, not how much has been there in the past.  In any case, we're releasing 8.1 Pg C/yr, and the atmospheric carbon is increasing at a rate of 3.2 Pg C/yr.

(again, the same source.)

I'd also like the naturalists to explain how earth has gone through ice ages and desert ages before humans even appeared.

That sounds an awful lot like a non-sequitur.

Edit note: the number should be 8.1, not 8.2.  I regret the error.

[Valynth]

... assuming none of it has been absorbed by growth, the oceanic sink, or elsewhere in the biosphere.

The first and third are unlikely, but i understand the second is a fairly big number.

According to the same source, the oceans absorb 2.1 Pg C/yr.

Rather than how the amount introduced by humans in the last 256 years(hey, 2^8, neat!) that compares to the current level of carbon, I'd like to see comparisons of carbon introduced by humans to carbon introduced by other sources and an analysis on carbon introduction and carbon removal.

The greenhouse effect is caused by how much carbon is in the air now, not how much has been there in the past.  In any case, we're releasing 8.2 Pg C/yr, and the atmospheric carbon is increasing at a rate of 3.2 Pg C/yr.

(again, the same source.)

Show me the math of how they got these numbers, then we'll talk.  I want to see every company that produces CO2 listed and I'll add all the numbers that aren't "estimations" as opposed to "this is how much they make."

I'd also like the naturalists to explain how earth has gone through ice ages and desert ages before humans even appeared.

That sounds an awful lot like a non-sequitur.

No it sounds like this problem has happened before our factories were even built so we'll just have to adjust around it, and guess what?  Our factories and machines help us to adjust around things.

Now, I'm not saying that I like waste, but I'm also saying that I'm not going to stop breathing just because some politician -thinks- there's a problem.

After all, if we have such a -masterfull- control over the environment, why are we constantly bombarded with tornadoes, hurricanes, and droughts?  And next time come up with something we don't do just by living.

[superluser]

Show me the math of how they got these numbers, then we'll talk.  I want to see every company that produces CO2 listed and I'll add all the numbers that aren't "estimations" as opposed to "this is how much they make."

Here's the methodology for the US; you should expect the numbers for the rest of the world to follow a similar methodology.  These have to be estimates, since no one is checking to see how much carbon is coming out of your tailpipe.

These can be very accurate.  If we take oil production and subtract oil reserves, that gives us oil consumption.  Multiply that by the fraction of oil refined into gasoline, and we get gasoline production.  Or just use the total sales of gasoline by gas stations.  Multiply that by the amount of carbon produced by burning gasoline, and you get the amount of carbon produced by the consumption of fossil fuels.  I suppose some people are eating gasoline, but I think that it's probably less than 7,4% of the gasoline sold (that's the uncertainty in the statistic).

We don't have an exact number of how many Tickle Me Elmos were produced.  I don't understand why you expect an exact number of how much carbon is produced, by which company, and at what time.  It's not like every country in the world is a communist dictatorship and can dictate exactly how much fossil fuel must be burned every year.

No it sounds like this problem has happened before our factories were even built so we'll just have to adjust around it, and guess what?  Our factories and machines help us to adjust around things.

Ice ages happen on time scales of tens of thousands of years.  The last one was some 20,000 years ago.  The data sets that we have for modelling the recent atmosphere and recent global temperatures are typically 1000-2000 years in length.  Some data sets are going to be available for 20,000 years ago that would not be available today (for example, He3/He4 ratios), while others are available today that would not be available for longer periods of time (such as data derived from living organisms).  As such, comparisons between models based on differing data sets are inappropriate and can be very misleading.

The ice ages were apparently caused by reduced insolation at high latitudes, due to an increase in the axial tilt and an increase in orbital eccentricity.  This is the Milankovitch cycle.  You can find references for it at the Wikipedia article.  Greenhouse gases also played a role in this, but it appears to be a minor one.

But this has precious little to do with the current rapid global warming.

After all, if we have such a -masterfull- control over the environment, why are we constantly bombarded with tornadoes, hurricanes, and droughts?  And next time come up with something we don't do just by living.

And that is a straw man.

[Reese Tora]

Rather than how the amount introduced by humans in the last 256 years(hey, 2^8, neat!) that compares to the current level of carbon, I'd like to see comparisons of carbon introduced by humans to carbon introduced by other sources and an analysis on carbon introduction and carbon removal.

The greenhouse effect is caused by how much carbon is in the air now, not how much has been there in the past.  In any case, we're releasing 8.2 Pg C/yr, and the atmospheric carbon is increasing at a rate of 3.2 Pg C/yr.

(again, the same source.)

I rather meant that I'd like the comparison to best estimates for carbon emissions from nonhuman sources.  All I can get from this is that at least 60.98% of the carbon emission from humans in any given year does not stay in the atmosphere, and that number only if humans account for all carbon emissions.  If the rest of the carbon emission from non human sources is even equal to the amount produced by human activities, the percentage becomes ~80.59%(still bad).

If the natural world is emitting a significantly larger amount of carbon than is human activity(in the range of hundreds of pg C/yr) then the amount of human contribution becomes less significant.  Granted, most of the carbon the natural world produces is in the form of methane, which lasts a much shorter time in the atmosphere compared to CO2, but it's still something that doesn't get mentioned often enough, IMO.  I think that, if the people preaching anthropogenic global warming could cite humans as producing a significant fraction of the green house gases released into the atmosphere each year, they would; the lack of any such citing makes me curious and a little suspicious.

[superluser]

I rather meant that I'd like the comparison to best estimates for carbon emissions from nonhuman sources.  All I can get from this is that at least 60.98% of the carbon emission from humans in any given year does not stay in the atmosphere, and that number only if humans account for all carbon emissions.  If the rest of the carbon emission from non human sources is even equal to the amount produced by human activities, the percentage becomes ~80.59%(still bad).

Interesting.  I'd like to know where these data are coming from, since it looks like a useful source.

The source that I've been using says that 120 Pg C/yr are transferred from the atmosphere to the land.  Almost all of this gets returned to the atmosphere.  There is a mean residence time of 17 years for carbon on land.  A further 90 Pg C/yr are transferred between the atmosphere and the oceans.  The mean residence time here is 400 years, but that's because, while most of the carbon is returned within a year, a small fraction remains sequestered for over a thousand years.  There are a couple of other sources, but they don't add up to more than 10 Pg C/yr.

That gives us 210 Pg C/yr transferred between the land and the air and the ocean and the air.  Most of this is in equilibrium, so there's no net change in the amount of carbon in any of these domains from carbon from natural sources.

That makes human sources of carbon responsible for 3.9% of the total carbon exchange.  Bear in mind that humans can account for about 250% of the carbon increase in the atmosphere.  If we reduced our emissions by 40%, we might wind up with zero year-to-year change in atmospheric carbon.  Note that I'm not sure that such a reduction would actually result in a one-to-one change in atmospheric carbon.

3.9% is still pretty significant.  Take, for example, an 8 oz glass.  Fill it with 8 oz of water.  Now add half an ounce (6%) of water to it.  You get a puddle of half an ounce of water.  That seems to be what we're seeing here.  The ecosystem is absorbing 4.9 Pg C/yr (60%) of the carbon that we're sending into the atmosphere, but the rest of it is not being absorbed and is contributing to global warming.

[Reese Tora]

Ah, thanks.

I can see why this isn't being waved as a battle standard now; it's large enough to be significant, but not to the average joe.

As for where my numbers came from, I just used the numbers you supplied (8.2 pg c/yr and 3.2 pg c/yr) and applied some maths to them.

Since the difference between emissions (8.2) and increase (3.2) is five, I divided 5 by 8.2 to arrive at the minimum percentage.  All my other numbers are extrapolated from that or made up for my 'if' statements.  It doesn't take into account the time that the different GHGs take to dissipate or thier global warming potential, which I believe I admited to, and should have if I didn't.

[superluser]

As for where my numbers came from, I just used the numbers you supplied (8.2 pg c/yr and 3.2 pg c/yr) and applied some maths to them.

I should have figured that out.  Sorry.  I'm presently running on about 3 hours of sleep, and yesterday, I was running on four. (Also. it seems I misquoted the first number, which should be 8.1 Pg C/yr)