The Climate Surprise

Figure 2.4: Higher levels of atmospheric CO2 support greater plant
growth in dry condions. This is a cause of the global greening of arid
regions as documented by space photographs.
plant growing in adequate water condions
will experience about a percent increase in
producvity for a ppm increase in CO. But
that same plant growing in a water-stressed
environment would experience a much greater
percent increase in producvity for a
ppm increase in CO. That benefit becomes
even larger as the CO concentraon rises.
Further, research shows that a doubling of
the air’s CO concentraon typically boosts the
opmum temperature for plant photosynthesis
by several degrees cengrade, and it raises the
temperature at which plants experience heatinduced
death by about the same amount.
Therefore, most types of vegetaon,
with the help of the extra CO, will likely
be able to tolerate much warmer living
condions than they do currently, even
if temperatures were to rise as high as
is unrealiscally predicted by the most
pessimisc climate models.
Based on a multude of real-world
observaons, the future is now. Evidence
from all across the globe indicates
that the terrestrial biosphere is
already experiencing a great planetary
greening, likely in large measure due to
the approximate percent increase in
atmospheric CO since the beginning of
the Industrial Revoluon.
Perhaps most surprising about these observations
is the fact that this great greening
of the Earth has occurred despite many
assaults of both man and nature on Earth’s
vegetation over this time period, including
fires, disease, pest outbreaks, deforestation,
war, and climatic changes in temperature and
precipitation.
In considering each of the CO enrichment
benefi ts discussed above, instead of
being shunned like the plague, the ongoing rise
in atmospheric CO should be welcomed with
open arms. Carbon dioxide is not a pollutant—
it is the very elixir of life.
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