Rob Dekker wrote:
"Roger Dewhurst" wrote in message
...
Tom P wrote:
On 08/19/2010 04:49 PM, matt_sykes wrote:
On 19 Aug, 16:20, wrote:
On Thu, 19 Aug 2010 05:58:42 -0700 (PDT), matt_sykes

wrote:
On 19 Aug, 14:20, Roger wrote:
Please see:
http://www.youtube.com/watch?v=g093lhtpEFo
"CO2 is plant food" is crock? How about sunlight? Is that also
crock? And water?
Idiot.

--http://desertphile.org
Desertphile's Desert Soliloquy. WARNING: view with plenty of water
"Why aren't resurrections from the dead noteworthy?" -- Jim Rutz
Estimates imply that below 200 PPM life on earth becomes untenable.
Historical records show CO2 as high as 5000 thousand of PPM. And our
current level is towards the bottom of that range. Life on earth
will benefit from a doubling of CO2. And since CO2 has not yet had a
marked effect on temperature and its effect is non linear there isnt
going to be any effect on temperature.
The problem with the "CO2 is plant food" argument is that in recent
decades the correlation between temperature and tree-ring growth has
broken down.
You would expect an increase in CO2 to display a beneficial effect on
tree-ring growth. But it doesn't. Trees are behaving as if the climate
were cooling. (Remember the "hide the decline"?)

T.


Most of the plant families we see today evolved in Mesozoic times. The
ginkgophyta evolved in upper Palaeozoic times and Gingo biloba, extant
now, evolved in Mesozoic times. It is fair to say that most plants evolved
in an atmosphere much richer in carbon dioxide.

R

Which evidence do you have that they respond very positively to increased
CO2 in the current climates ?

Greenhouse operators pumping carbon dioxide into their greenhouses to
increase the growth rate? Is that enough?

R