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As a general rule, the most successful man in life is the man who has the best
information
The Earth's climate has been continuously changing throughout its history. From ice covering large amounts of the globe to interglacial
periods where there was ice
only at the poles - our climate
and biosphere has been in flux for millennia.
This temporary reprieve from the ice we are now experiencing
is called an interglacial period - the respite from the cold locker began 18,000 years ago as the earth started heating up and warming its way out of the Pleistocene Ice Age.
Approximately every
100,000 years or so our climate warms
up temporarily.
These interglacial
periods usually last somewhere between 15,000 to
20,000 years before another ice age
starts. Presently we’re at year 18,000 of the current warm
spell.
Serbian astrophysicist
Milutin Milankovitch is best known for developing one of the most significant theories relating to Earths motions and
long term climate change.
Milankovitch developed
a mathematical theory of climate change based on the seasonal and latitudinal variations in the solar radiation received by the
Earth from our Sun - it was the first truly plausible theory for how minor shifts of
sunlight could make the entire planet's temperature swing back and forth
from cold to warm.
Milankovitch’s Theory
states that as the Earth travels through space around the sun, cyclical variations in three elements of Earth/sun/geometry
combine to produce variations in the amount of solar energy that reaches
us. These three elements are:
- Variations in the Earth's orbital eccentricity
- the shape of the orbit
around the sun, a
100,000 year cycle
- Changes in obliquity
or tilt of the earth’s axis - changes in
the angle that Earth's
axis makes with the
plane of Earth's orbit,
a 41,000 year cycle
- Precession - the change in the direction of
the Earth's axis of rotation, a 19,000 to
23,000 year cycle
These orbital processes are thought to be the most significant
drivers of ice ages and, when combined, are known as Milankovitch Cycles.
Other Climate
Change Drivers:
- Changes occurring
within the sun
affects the intensity of sunlight that reaches the Earth's surface. These
changes in intensity can
cause either warming
- stronger solar intensity - or cooling when solar intensity is weaker.
- Volcanoes often
affect our climate
by emitting aerosols
and carbon dioxide into the atmosphere. Aerosols block sunlight and contribute
to short term cooling,
but do not stay in the atmosphere
long enough to produce
long term change. Carbon
dioxide (CO2) has a warming
effect. For about two-thirds
of the last 400 million years, geologic evidence suggests CO2 levels and temperatures were considerably higher than present. Each year 186 billion tons
of carbon from CO2 enters the earth's atmosphere - six billion tons are from human activity, approximately 90
billion tons come from biologic activity in earth's oceans and another 90
billion tons from such
sources as volcanoes and decaying
land plants
These climate
change “drivers” often trigger additional changes or “feedbacks” within the climate system that can amplify
or dampen the climate's
initial response to them:
During at
least the last 650,000 years, CO2 levels have tracked the glacial
cycles - during warm interglacial
periods, CO2 levels have
been high and during cool
glacial periods, CO2 levels
have been low
- The heating
or cooling of the Earth's
surface can cause changes in ocean currents. Ocean currents play a significant role in distributing heat around the Earth so changes in these currents can bring about significant changes in climate
from region to region
In 1985 the Russian Vostok Antarctic drill team pulled up cores of ice that stretched through a complete glacial
cycle. During the cold period
of the cycle CO2 levels were
much lower than during the warm periods before and after. When plotted
on a chart the curves of
CO2 levels and temperature
tracked one another very closely – methane, an even more potent greenhouse gas, showed a similar rise and fall to that of CO2.
Small rises or falls in temperature - more, or less
sunlight - seemed to cause a
rise, or fall, in gas levels. Changing
atmospheric CO2 and methane
levels physically linked the Northern and Southern hemispheres, warming or cooling the planet as a whole. In the 1980s
the consensus was that
Milankovitch’s Cycles would
bring a steady cooling over the next few thousand years.
As studies of past ice ages continued
and climate models were improved worries about a near term re-entry into the cold locker died away – the models now said
the next ice age would not come within the next ten thousand years.
It’s obvious
that the orbital changes, as explained
by Milankovitch’s Theory,
initiate a powerful
feedback loop. The close of a glacial era comes when
a shift in sunlight causes a slight rise in temperature - this raises gas
levels over the next few hundred years and the resultant greenhouse effect drives the planet's temperature higher, which drives a further rise in the gas levels and so on.
The exact
opposite happens when
sunlight weakens, we get a shift from emission to absorption of gases
which causes a further fall in temperature... and so forth.
How Higher Temperatures effect Food Production
The study Climate Trends and Global Crop
Production Since 1980 compared yield figures from the Food and
Agriculture Organization (FAO) with
average temperatures and precipitation in major growing regions.
Results indicated
average global yields for
several of the crops studied responded negatively to warmer temperatures. From 1981 - 2002,
warming reduced the combined production of wheat,
corn, and barley - cereal
grains that form the foundation of much of the world's diet - by 40 million metric tons per year.
The authors said the main value of their study was
that it demonstrated a clear and simple
correlation between temperature increases and crop yields at
the global scale.
"Though the impacts are relatively
small compared to the technological yield gains over
the same period, the results demonstrate that negative impacts are already occurring."
David Lobell, lead researcher
Other researchers
who focused on wheat, rice, corn, soybeans, barley and sorghum (these crops account for 55 percent of
non-meat calories consumed
by humans and contribute
more than 70 percent of the world's
animal feed) reported that each had
a critical temperature threshold above which yields started plummeting, for example: 29°C for corn and 30°C for soybeans. At the International Rice Research Institute in the
Philippines scientists have found
that the fertilization of
rice seeds falls from 100 per cent at 34 degrees to near zero at
40 degrees.
By 2050, the world's population is expected to reach around nine billion - minimum
and maximum projections range from 7.4 billion to
10.6 billion.
"Future food-production
increases will have to
come from higher yields. And though I have no doubt yields will keep going
up, whether they can go up enough to feed the population monster is another matter.
Unless progress with agricultural yields remains very strong, the next century will experience sheer human misery that, on a numerical scale, will exceed
the worst of everything that has come before".
Norman Borlaug, father of
the Green Revolution
Unfortunately the Green Revolutions high yield
growth is tapering off and in some cases declining. So far this is mostly because
of an increase in the price
of fertilizers, other chemicals and fossil fuels, but
also because the overuse of chemicals has exhausted the soil and
irrigation has depleted water aquifers.
If we are to stay in this current inter-glacial period for up to another 10,000
years, as current climate models predict, are we going to see regular occurrences of temperatures
rising above plants critical flowering thresholds?
Considering population growth, draining of fresh water aquifers and declining plant yields it seems as if the supplies for
drinking water/irrigation, and food,
are going to come under
increasing pressure while
at the same time demand is going
to increase.
Nuclear power (while reducing greenhouse gases in the atmosphere) where used for desalination of seawater would supply fresh water for the most parched areas of the globe
while reliving strain on area aquifers. Farmers are going to have to grow more food on less acreage which means increased use of fertilizers.
Rare Earth Elements (REE) applications are highly
specific and substitutes are inferior
or unknown. REE are environmentally
friendly, reducing CO2 levels, and are going to continually come under greater supply pressure
as demand increases, for example:
- Rechargeable batteries
- Automotive pollution control catalysts
- Neodymium is key to the permanent magnets
used to make high-efficiency electric motors. Two other REE minerals -
terbium and dysprosium – are added to neodymium to allow it to remain magnetic at high temperatures
- Y, La, Ce, Eu, Gd, and Tb are used in the new energy-efficient
fluorescent lamps. These
energy-efficient light bulbs are 70% cooler in terms of the heat they generate and are 70% more efficient in their use of electricity
- Rare-earth
elements are used in
the nuclear industry
in control rods, as dilutants,
and in shielding, detectors and counters
- Rare metals
lower the friction on power lines, thus cutting electricity leakage
The rechargeable
power needs of our modern
society has made lithium a serious player in the commodity markets, and no segment is
more important than electric
vehicles (EVs). EVs have far fewer moving parts than Internal Combustion Engine
(ICE) gasoline-powered cars - they
don't have mufflers, gas tanks, catalytic converters or ignition systems,
there’s also never an oil change or tune-up
to worry about getting done. Plug and go, pretty convenient and very green!
But the clean and green doesn’t end there - electric
drives are more efficient then the drives on ICE powered cars. They are able to convert more of the available energy to propel the car therefore using less energy to go the same distance. And applying the
brakes converts what was simply
wasted energy in the form of heat to useful energy in the form of electricity to help
recharge the car’s batteries.
Are nuclear energy, fertilizers, lithium and rare earths
on your radar screen?
If not, maybe they should
be.
Richard Mills
Aheadoftheherd.com
If you're
interested in learning more about the junior resource market please come and
visit Richard at www.aheadoftheherd.com. Membership is free, no credit card or personal
information is asked for.
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