[Coral-List] A little more La Ninia

David M. Lawrence dave at fuzzo.com
Sat Dec 4 10:15:39 EST 2010

Your expert needs to understand terrestrial ecosystems better, 
particularly temperate coniferous and deciduous forests.  If you notice 
the curve, the CO2 levels rise from a monthly low about December.  
"Frozen leaves" (and needles and fronds) aren't giving off anything.  
(Leaves themselves are somewhat irrelevant in this context -- while they 
are generally the only eukaryotic cells with chloroplasts, hence capable 
of photosynthesis, every eukaryotic cell has mitochondria, which are 
capable of respiration, i.e., converting carbon fuel to carbon 
dioxide.)  Even when dormant, trees are respiring -- they still need 
energy to LIVE, and that energy is produced by either aerobic or 
anaerobic respiration.  Either process gives off carbon dioxide.

Much of the carbon dioxide emissions in late fall, winter, and early 
spring are driven, however, by bacteria and fungi -- the decomposers who 
are breaking down the stuff that died or was shed at the end of the 
previous growing season.  Again, they are producing energy by aerobic or 
anaerobic respiration.  In other words, converting carbon stored in 
organic matter to carbon dioxide that is released back into the atmosphere.

What your expert failed to note was the incredible amount of carbon 
dioxide taken up by northern temperature forests in the late spring and 
summer as they begin their growing season.  That growth -- dependent on 
fixing carbon through photosynthesis -- removes massive amounts of CO2 
from the atmosphere.  I'm sure a similar increase in carbon demand takes 
place in northern temperature seas, but because of the uneven 
distribution of land and water -- particularly at the higher latitudes 
-- the terrestrial ecosystems have more of a effect on seasonal 
variation in global atmospheric CO2 concentrations.

Please, Gene, make sure your experts really know what they are talking 
about before you cite them...


On 12/3/2010 2:32 PM, Eugene Shinn wrote:
> My apology note to David regarding the origin of the positive CO2
> spikes on the Keeling curve prompted an offline counter argument. The
> writer says the CO2 spikes in winter are more likely the result of
> reduced phytoplankton growth during winter months so less CO2 is
> consumed by marine plankton. He argues that "frozen leaves and
> dormant trees in the northern hemisphere forests are not likely to
> give off much CO2. Gee, how is a person to know which expert to
> believe? Gene

  David M. Lawrence        | Home:  (804) 559-9786
  7471 Brook Way Court     | Fax:   (804) 559-9787
  Mechanicsville, VA 23111 | Email: dave at fuzzo.com
  USA                      | http:  http://fuzzo.com

"All drains lead to the ocean."  -- Gill, Finding Nemo

"We have met the enemy and he is us."  -- Pogo

"No trespassing
  4/17 of a haiku"  --  Richard Brautigan

More information about the Coral-List mailing list