ENVIRONET Archives

November 2005

EnviroNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Brian Ellis <[log in to unmask]>
Reply To:
Environmental Issues <[log in to unmask]>, Brian Ellis <[log in to unmask]>
Date:
Sun, 6 Nov 2005 11:54:33 +0200
Content-Type:
text/plain
Parts/Attachments:
text/plain (137 lines)
Hee, hee! Alexander Pope said "A little learning is a dangerous thing" 
and you neatly demonstrate that. The figures you quote are for carbon, 
not for carbon dioxide. In round figures, the atomic weight of carbon is 
12. The molecular weight of CO2 is 44. Therefore, for every unit of 
weight of carbon in carbon dioxide, you have 44/12 = 3.67 units of 
weight of the gas itself.

If all the carbon were in the form of CO2 (which it isn't) your figures 
of 6.6 ± 0.6 of C become ~24 Gt ± 2.2 Gt of CO2 and 5.5 from your other 
source becomes ~20 Gt of CO2, so my 15 billion tonnes is VERY conservative.

And a tonne = 1,000 kg. The term "metric ton" is inadmissible, according 
to ISO 35/1 standards.

Hope this helps your understanding!

Brian

Charles Dolci wrote:
> Brian:
> According to your post the amount of  CO2 emitted by man annualy  is 15
> billion tonnes (I assume that is metric tons).  You should check your
> sources.
> Doing a bit of digging I found a few references to anthropogenic
> emissions of CO2
> 
>  From "Trends in Global Emissions: Carbon, Sulfur and Nitrogen" by
> Arnolf Grubler (International Institute for Applied Systems Analysis,
> Laxenberg Austria
> in the Encyclopedia of Global Environmental Change (ISBN 0-471-97796-9)
> published in 2002
> 
> Page 2
> "Compared to the size of annual fluxes that characterize the carbon
> cycle and its inter-annual variations, anthropogenic altrerations to the
> carbon cycle are comparatively small and hence impossible to measure
> directly. Emmission estimates need therefore  to be based on inventory
> data linking socio-economic activity data such as fossil fuel use  or
> land use changes ..."
> 
> "Currently (AD 2000), human-induced alterations to carbon flows include
> emissions of some 6.6 (+/_ 0.6) Pg C year from industrial activities
> (mostly the burning of fossil fuels) that constitute a net addition to
> natural carbon fluxes, albeit not necessarily in the same year. In
> addition, estimates indicate a net additional flux of about one
> (uncertainty range: 0-2.8)Pg C year from the burning of biomass and
> changes in soil carbon in conjunction with land use changes."
> 
> Source:
> http://www.iiasa.ac.at/Research/TNT/WEB/Publications/Trends_in_Global_Emissions/egec_sulfur.pdf 
> 
> 
> So what he is saying is that they really cannot determine actual amounts
> so they have to make estimates based on economic factors such as amount
> of  fuels consumed. OK, I'll go along with that, but Brubler says that
> the amount is ONLY 6.6 Pg C (i.e. 6.6 billion metric tons) per year.
> Quite a bit less than 15 billion.
> 
> I also found, at http://www.fao.org/clim/docs/1-3.HTM
> 
> XI WORLD FORESTRY CONGRESS
> Antalya, Turkey, 13 to 22 October 1997
> 
> VOLUME 1, TOPIC 4
> 
> FORESTS AND CLIMATE CHANGE: ROLE OF FOREST LANDS AS CARBON SINKS
> Sandra Brown (US Environmental Protection Agency, National Health and
> Environmental Effects Research Laboratory, Western Ecology Division)
> 
> 
> "The estimated net C flux from the world's forests is a source of 0.9 ±
> 0.5 Pg/yr, or about 16% of the amount produced by burning fossil fuels
> and cement manufacture. The error terms associated with the C flux
> estimate are basically derived from the range of values resulting from
> the use of different assumptions in the C budgets for a given country or
> region. They do not represent errors derived from statistical
> procedures. Error enters the flux estimation procedure through
> uncertainties and biases in the primary data and these compound as the
> data are combined to draw inferences (Robinson 1989). Many estimates for
> components of the forest sector C budget are probably known no better
> than ± 30% of their mean and others may be known no better than >± 50%
> of their mean (Robinson 1989). These errors are compounded in making
> global estimates of C flux, perhaps to large proportions, but to what
> extent is presently unknown.
> 
> The average annual global C budget for the 1980s is estimated as follows
> (Schimel et al. 1995):
> 
>   Pg C yr
> Emissions from fossil fuel and cement production    5.5 +/- 0.5
> Emissions from change in tropical land use             1.6 +/- 1/0
> Total emissions                                                     7.1
> +/- 1.1
> 
> 
> So Brown estimates emissions at ONLY 5.5 Pg C (i.e. 5.5 billion metric
> tons) per year.
> 
> Chuck
> 
> 
>>
>> Brian Ellis wrote:
>>
>>> What you are saying is that the annual 15 billion tonnes of CO2 that are
>>> spewing out of our chimneys and exhaust pipes, year in, year out, is for
>>> nought? PLEEEEEEZE! Nor the 6 billion tonnes that are not absorbed
>>> because of deforestation.
>>>
>>> Yes, the ocean surface waters contain 1000 billion tonnes of carbon,
>>> some in life forms, some in dissolved CO2, but the annual carbon
>>> emissions from the oceans are 90 billion tonnes, whereas the absorption
>>> by the oceans is 92 billion tonnes. In fact, the annual increase of
>>> carbon in the surface oceans is only 1 billion tonnes, because there are
>>> other interchanges into deep waters and, eventually into sedimentation.
>>> [figures from Sundquist, Trabalka, Bolin and Siegenthaler, IPCC 1990]
>>>
>>> Sorry, if your hypothesis were correct, we would be in a positive
>>> feedback cycle, snowballing into ever-increasing GHG emissions, causing
>>> more global climate change, causing more ocean heating... Hopefully, we
>>> are not there - yet.
>>>
>>> No, I'm sorry, it is you and I who are responsible, not some quirk of
>>> nature. This is now definite and no apologetics of bad science will
>>> diminish our responsibilty. Even GWB is admitting it!
>>>
>>> Brian
>>
>>
>>
>>
> 

-- 
______________________________________________
Please note new e-mail address [log in to unmask]

ATOM RSS1 RSS2