There is no Planet B

[Lake-Effect]

Originally Posted by kmacdonald

If CO2 in the atmosphere increased 40% due to burning of fossil fuels, it doesn't seem to have that great of an impact on the earths temperature. Is the warming effect being offset by a cooling mechanism?

As I mentioned, and described in many places, the amount of CO2 added by recent human activity has been sufficient to change what would have been a cooling trend into a warming trend. That's somewhat significant...

Another fun fact - the heating effect of additional CO2 lags its addition by about 20+ years. So the heating we're currently seeing was from emissions prior to 2000; we've yet to 'enjoy' the heating from the emissions of the last two decades

Will we run out of fossil fuels before heating the planet to unacceptable levels?

It seems not. However, burning up all the planet's fossil fuels over the next century or two seems shortsighted anyway, so it wouldn't really be a bad thing to use it more slowly and more for things like chemicals, pharmaceuticals, plastics etc. Would be nice to make fossil resources last a millenium or more, I think.

Originally Posted by oldjags

It's generally accepted that CO2 emissions prior to WW2 were insignificant, and cannot be used to explain the temperature increase we saw up to that point coming out of the little ice age. I think we can all stipulate that those increases were totally natural in origin.

I don't think the pre WW II emissions are insignificant. So, no, not stipulated. We would of course consider any sources you have to back up this assertion. Til that is proven, your arguments based upon this are therefore not relevant.

It is estimated that 3-4% of the atmosphere's CO2 is man-made.

No, it is estimated that the 40% increase in the CO2 in the atmosphere is due to recent human activity.

So again, your conclusions based upon these errors are not persuasive.

[Lake-Effect]

Originally Posted by newhaul

um wrong
It has a lot to do with everything.
C12 comes from rotting vegetable matter or burning of current vegetation .
C13 comes from oceanic outstanding due to the sun warming the surface .
C14 comes from sources that are over 25,000 years old.

This is essentially wrong, or you've mangled it somehow. Try again.

[newhaul]

Originally Posted by SailOar

Why did climate cool in the mid-20th Century?


For a more complete explanation see:

https://www.skepticalscience.com/glo...y-advanced.htm

serious question so we all understand the players here

What MMGWC/ agw think tank are you posting for or on the behalf of.

[kmacdonald]

Originally Posted by Lake-Effect

As I mentioned, and described in many places, the amount of CO2 added by recent human activity has been sufficient to change what would have been a cooling trend into a warming trend. That's somewhat significant...

Really? Don't you mean the total increase in CO2 and not the 3 or 4% of it that is man made?

[newhaul]

Originally Posted by Lake-Effect

This is essentially wrong, or you've mangled it somehow. Try again.

auto correct it was outgassing not outstanding for the oceans.
essentially correct .
Reread the books you missed some real important parts

[GordMay]

Originally Posted by newhaul

... By knowing the proportions of each of the carbon isotopes at a given time you can extrapolate what the source of said carbon is ...

Originally Posted by newhaul

you are the ones that say that co2 is leading warming so now prove your assertion and be specific as to c12/c13/c14 rising ratios and the likely sources of each. Also how you came to your conclusions.

Globally, as atmospheric carbon dioxide levels continue to increase, both Δ14C and δ13C are decreasing over time (Suess Effect*).
CO2 ➥ https://www.esrl.noaa.gov/gmd/dv/iad...m=ccgg&type=ts
C13/C12 in CO2 ➥ https://www.esrl.noaa.gov/gmd/dv/iad...m=ccgg&type=ts

Carbon-13 in CO2 is decreasing, as the fraction of atmospheric CO2 that is realized from combustion of fossil carbon, is increasing. Ratios of 13C/12C in CO2 tend to be lower in the Northern Hemisphere, suggesting a fossil-fuel source that resides mainly in the Northern Hemisphere.

Carbon-14 in CO2 is decreasing, and 14C/12C ratios are lower in the Northern Hemisphere than in the Southern Hemisphere, suggesting a northern hemisphere source of 14C-depleted carbon (e.g., fossil fuels). However, things are not quite that simple; although 14C from bomb testing has largely been removed from the atmosphere by the biosphere, the biosphere is now giving some back, precluding any simple interpretation of the rate of 14C decline. For more on this topic, see Levin et al. (2010).

The carbon from fossil fuels, that is returned to the atmosphere through combustion, is depleted in both 13C and 14C compared to atmospheric carbon dioxide. The added CO2 in the atmosphere since the industrial revolution has shown exactly the “isotopic signature” of fossil-fuel CO2.

CO2 produced from burning fossil fuels or burning forests has a different isotopic composition from CO2 in the atmosphere, because plants have a preference for the lighter isotopes (carbon-12 and 13); thus they have lower carbon-13 to 12 ratios. Since fossil fuels are ultimately derived from ancient plants, plants and fossil fuels all have roughly the same carbon-13 to 12 ratio, about 2% lower than that of the atmosphere. As CO2 from these materials is released into, and mixes with, the atmosphere, the average carbon-13 to 12 ratio of the atmosphere decreases. The carbon-14 ratio has also decreased significantly.

Reconstructions of atmospheric carbon isotope ratios from various proxy sources have determined that at no time in the last 10,000 years are the carbon-13 to 12 ratios in the atmosphere as low as they are today. Furthermore, the carbon-13 to 12 ratios begin to decline dramatically just as the CO2 starts to increase — around 1850 AD.

This is exactly what we expect if the increased CO2 is in fact due to fossil fuel burning beginning in the Industrial Revolution.

[newhaul]

Originally Posted by Lake-Effect

As I mentioned, and described in many places, the amount of CO2 added by recent human activity has been sufficient to change what would have been a cooling trend into a warming trend. That's somewhat significant...
.

explain the part of it should be a cooling trend exactly
Aside from the fact we are seeing cooling now

[Lake-Effect]

Originally Posted by kmacdonald

Really? Don't you mean the total increase in CO2 and not the 3 or 4% of it that is man made?

The 40% increase in atmospheric CO2 is clearly due to human activity.

(and what do you mean by "man-made" anyway? Breathing?)

[Lake-Effect]

Originally Posted by newhaul

Aside from the fact we are seeing cooling now

Wow. Newhaul can spot normal variance. Film at 11...

[newhaul]

Originally Posted by GordMay

Globally, as atmospheric carbon dioxide levels continue to increase, both Δ14C and δ13C are decreasing over time (Suess Effect*).
CO2 ➥ https://www.esrl.noaa.gov/gmd/dv/iad...m=ccgg&type=ts
C13/C12 in CO2 ➥ https://www.esrl.noaa.gov/gmd/dv/iad...m=ccgg&type=ts

Carbon-13 in CO2 is decreasing, as the fraction of atmospheric CO2 that is realized from combustion of fossil carbon, is increasing. Ratios of 13C/12C in CO2 tend to be lower in the Northern Hemisphere, suggesting a fossil-fuel source that resides mainly in the Northern Hemisphere.

Carbon-14 in CO2 is decreasing, and 14C/12C ratios are lower in the Northern Hemisphere than in the Southern Hemisphere, suggesting a northern hemisphere source of 14C-depleted carbon (e.g., fossil fuels). However, things are not quite that simple; although 14C from bomb testing has largely been removed from the atmosphere by the biosphere, the biosphere is now giving some back, precluding any simple interpretation of the rate of 14C decline. For more on this topic, see Levin et al. (2010).

The carbon from fossil fuels, that is returned to the atmosphere through combustion, is depleted in both 13C and 14C compared to atmospheric carbon dioxide. The added CO2 in the atmosphere since the industrial revolution has shown exactly the “isotopic signature” of fossil-fuel CO2.

CO2 produced from burning fossil fuels or burning forests has a different isotopic composition from CO2 in the atmosphere, because plants have a preference for the lighter isotopes (carbon-12 and 13); thus they have lower carbon-13 to 12 ratios. Since fossil fuels are ultimately derived from ancient plants, plants and fossil fuels all have roughly the same carbon-13 to 12 ratio, about 2% lower than that of the atmosphere. As CO2 from these materials is released into, and mixes with, the atmosphere, the average carbon-13 to 12 ratio of the atmosphere decreases. The carbon-14 ratio has also decreased significantly.

Reconstructions of atmospheric carbon isotope ratios from various proxy sources have determined that at no time in the last 10,000 years are the carbon-13 to 12 ratios in the atmosphere as low as they are today. Furthermore, the carbon-13 to 12 ratios begin to decline dramatically just as the CO2 starts to increase — around 1850 AD.

This is exactly what we expect if the increased CO2 is in fact due to fossil fuel burning beginning in the Industrial Revolution.

hmmm a decrease in the c14 in the atmosphere . Isn't c14 mostly from combustion of " the evil fossil fuel" along with an increase in c12/c13 . Which are from more short term sources? Ie: not from man burning " those pesky fossil fuels ?

[newhaul]

Originally Posted by Lake-Effect

Wow. Newhaul can spot normal variance. Film at 11...

according to your climate models we should have warming . After all they did say we are in an El Nino phase of the ENSO .

[newhaul]

Originally Posted by Lake-Effect

The 40% increase in atmospheric CO2 is clearly due to human activity.

(and what do you mean by "man-made" anyway? Breathing?)

the percentage of c14 ( from fossil fuel usage) is on the decline so what is the human footprint besides the increases of c12/ 13 which can and yes do come from breathing ( humans exhale approx 40,000 ppm of co2 )

[newhaul]

Originally Posted by Lake-Effect

Wow. Newhaul can spot normal variance. Film at 11...

a bit condescending there aren't you

[kmacdonald]

Originally Posted by Lake-Effect

The 40% increase in atmospheric CO2 is clearly due to human activity.

(and what do you mean by "man-made" anyway? Breathing?)

WOW. You really don't know much about this stuff.

[oldjags]

Originally Posted by hpeer

As we release CO2 into the atmosphere it begins to heat Earth, but the heating takes quite a while and the CO2 hangs around a long time. So if we dump X Amount of CO2 into the atmosphere it takes something like 500 years for the atmosphere to reach its maximum temperature. Of course in the meantime we have felt only a small fraction of the warming that is predicted based on CURRENT CO2 release. If we continue to release, then the ultimate change is going to be bigger yet.

So that’s a tricky bit for people to get, there is very little immediate feedback, the effects of what we do today won’t be fully felt for a generation or two or more. That century+ time delay is something the human mind has not been prepared to cope with. Folks want to see the problem in real time and address it in real time.

So this little post is not about debunking your alternative, just pointing out why CO2 is so much a bigger problem, even if the direct evidence is currently slight.

It is certainly true that the climate is slow to respond to changes in input, but if you are talking about a 100+ year delay in feedback, then what we are seeing now in temperature rise was caused by something a century ago, not by what we have done recently, which won't be felt for another 100 years. If that's the case, we truly are in deep doo-doo! I don't think that's the case though.

We do know that CO2 outgassing from the oceans due to warming following the end of glaciation periods lags the temperature rise by hundreds of years, so some portion of our current rise is simply due to us coming out of the little ice age 200 years ago.