C3
and C4 refers to the chemical pathway used by the chlorophyll in plant leaves
to produce sugar. C4 plants include many grasses and corn. It has been argued
that C4 plants are immune to changes in CO2, but as you can see in the
illustration above, this is clearly not true. They just don’t respond as
dramatically as C3 plants. They do, however, become more drought tolerant due
to the stomata response reducing water vapor loss.
Plants
need 3 major inputs to grow: water, CO2, and nitrogen. From these they produce
sugar for energy and proteins and cellulose for structure. Some have argued
that increased CO2 produces protein-poor plants. This is true only if increased
nitrogen is not supplied along with the increased CO2. A plant needs both in
balance. Any greenhouse farmer knows this. But still, this increased growth
with increasing CO2 assumes no improvement from fertilization, genetic
engineering or plant breeding.
The
experiments have been done holding all factors except CO2 constant. That
increase from CO2 alone is about 100 million metric tons for each 15% increase
in yield per year. That feeds about 700 million more people if one assumes 150
kg of rice per person per year. Imagine the gain if additional fertilizer was
supplied along with the increase in CO2. Wheat production with double the
current levels of CO2 increased by up to 38 percent (see here).
Corn responds to elevated CO2 by needing less water (see here). It is
clear that CO2 increases will greatly improve our ability to feed a growing
world population.
If
we try to limit CO2, we will dramatically limit the economic growth of the
world with no effect on the climate. This is already happening in Europe.
Taxing CO2 in efforts to limit production of it only makes money for the Al
Gore’s of the world. It limits our use of the energy we need for economic
growth and the CO2 that our crops need to flourish. Limiting CO2, even if we
could, would literally mean the starvation of a billion people in the next 50
years.
What
is more important? Feeding and lifting most of the world from poverty orr
preventing a questionable slight temperature rise which would lengthen the
growing season? The Global Warming crowd is trying to snatch defeat from the
jaws of victory.
No comments:
Post a Comment