Transcript Climate of the Earth: CO2 and Climate Change

The Climate of the Earth: CO2
and “Climate Change” (=Global
Warming)
Note: “climate change” was a term invented by
Republican pollster Frank Luntz, for the Bush
Administration in 2003, for political reasons.
I’ll use “Global Warming” as it’s more accurate and
doesn’t have the political spin.
Is there a Scientific Controversy
about the Cause of Global
Warming?
• No. Climate scientists themselves are
convinced by the evidence – global warming
is human-caused, primarily by fossil fuel
burning. And have been, for over 20 years
• AGW = Anthropogenic Global Warming, a useful
abbreviation
• Millions of dollars of oil money is financing an
ugly mis-information campaign to seed cynicism
towards legitimate science in the American
public and in politicians about the cause. See
my website page on the politics here.
Note How The More Closely You Understand
Climate Science, The More Convinced You are that
Global Warming is Human-Caused
Are Global Average Temperatures Rising
Significantly compared to Recent Geologic
History? Yes.
Longer Term: Over Several
Hundred Thousand Years - Ice
Ages
• Ice Ages show a strong correlation with small
changes in the Earth’s orbital ellipticity,
orientation, and angle of the Earth’s spin axis. As
these go through cycles – the Milankovitch
Cycles – the amount of heat delivered to the
Arctic Circle varies, showing a strong correlation
with inducing Ice Ages
• Reason: Ice is its own refrigerant. White ice
reflects incoming sunlight, radiates little IR. More
ice means more reflection, means more cooling,
means more ice… etc.
• Without Humans to add large amounts of greenhouse
gases (GHG’s) to the atmosphere, temperatures rose
and fell with very slow geological changes (or
occasionally, by a big comet/asteroid impact)
• Rising temperatures will slowly lower the amount of CO2
that can be dissolved in the oceans, pulling it out and
adding to GHG warming coming out of an Ice Age. This
mechanism explains why temperature rises preceeded
CO2 rises IN THE PREHISTORIC GEOLOGIC
RECORD.
• This is NOT relevant for today’s Global Warming, which
is caused by GHG’s, not slow Milankovitch cycles or
other slow natural changes.
• Note the Temperature Range: Roughly 6 degrees C.
That’s the same temperature changes climate
models say we can expect – not in ~100,000 years,
but this century.
• So – YES – today’s global warming is significant!
So; Temperatures are Rising Rapidly. Do we Know for Sure that
CO2 is Rising and in a Significant Amount? YES.
The Rising Atmospheric CO2 is clearly in Agreement with
Rising CO2 emissions by Human Activity
Is there Other Evidence that Rising CO2
levels are Caused by Humans? Yes.
• #1. Carbon isotope ratio C14/C12 in the atmosphere is
dropping, exactly as calculations say it should, as very
low C14/C12 carbon from oil and coal dilutes the higher
C14/C12 carbon which has existed in the atmosphere for
millions of years.
• (Note: C14 is created high in the atmosphere from N14 by
high energy solar wind and cosmic rays), and C14 decays
in a few thousand, not hundreds of millions of years
(when ancient plants were buried to produce today’s oil
and coal reserves), so the C14/C12 ratio from long-buried
oil is extremely low.
• #2. Known production levels of CO2 from mining and oil
production fit with the rate of observed rising CO2 levels.
See following slides.
Global Temperatures vs Atmospheric CO2 vs CO2 Emissions by
Humans – Last 1000 Years
So, OK – Temperatures are
rising dramatically, and so are
CO2 levels, and so are human
generated CO2 Emissions. But,
couldn’t there be other causes
of global warming that might be
as significant or more so, than
human activities?
The ONLY Known Mechanism which produces Heating of the
Lower Atmosphere AND Cooling of the Stratosphere – is:
Rising Greenhouse Gas Concentrations
…And Observations Show that Indeed, the
Stratosphere is Cooling
Another Key – Nighttime Temps Rising
faster than Daytime Temps
• This is expected only from rising
greenhouse gas concentrations, because
of the lag effect of temperature rise during
the day; hot ground at night can’t radiate
away its heat because of CO2 blanket
• If the sun were somehow causing rising
temps, you would expect day temps to be
rising faster than night temps. We see the
opposite…
DTR = Daily Temp Range: 2000 vs
1951.
But Couldn’t there still be something Else? Other
Influences Causing Global Warming, Not Us? No. The
green (greenhouse gas) Curve Dominates
Climate Modelling Has Improved Dramatically. Climate
Models Can ONLY Fit the Observational Data if ManMade GHG’s are Included
But What About Subtle, Indirect
Causes…
•
1. Svensmark Hypothesis: Cosmic Rays causing
cloud condensation nucleation, and low clouds
would cool the surface, so maybe this amplifies the
weak solar radiation effect?
• No – First, the theory doesn’t make sense. There’s
plenty of potential cloud nuclei w/o having to make more
from cosmic rays. Second, the observations don’t show
a believable correlation, and third and most important –
the solar cycle shows no trend for the past 60 years,
precisely when global warming has been most severe
and accelerating.
• While cosmic ray flux does correlate strongly with solar
cycle, the observed correlation between solar cycle and
temperatures is directly explained by the known (small)
change in solar irradiance with solar cycle, only
coincidentally with cosmic ray influx.
Svensmark’s is the Only Idea I’ve
Seen which isn’t Outright Climate
Denialism at Work…. And Yet You See
that it, Too, is Wrong.
• The politics of climate is ugly. See my
website for details. Look especially at the
YouTube’s “Climate Crock of the Week”
series, which are faithful to good science,
and also entertaining. Linked near the top
of this page
Industry Science – If Your Science Hurts Profits, Don’t
Expect Objective Honesty! Example…
•
Conclusion – Industry “science” is suspect.
Industry hires scientists to help it earn profits.
If there’s a conflict between the Truth, and
profits….. You can guess which wins
• It may not always be the scientists themselves who
buckle under threat of losing their jobs – industry may
simply ignore or de-fund studies which to not serve their
profits
• Contrast with Academia, where support comes from the
NSF, NASA, and generally unbiased funding sources.
• Academic scientists publish in peer-reviewed journals.
Industry scientists often can’t make the grade in true
journals, and end up having to publish in “trade journals”,
which have a poor track record of objectivity.
What Are the Effects of Global
Warming?
• Rapid melting of the Arctic. The long term ice of the Arctic Ocean is
already almost gone, and predicted to vanish entirely in just 20
years!
• Greenland is losing ice at an accelerating rate
• Rising sea levels
• Desertification of the mid latitudes is accelerating
• Migration of tropical diseases to mid latitudes. Malaria is already
now being found in south Texas
• Massive dying of forests as pests which used to be held in check by
cold winters are now multiplying. This releases yet more CO2
• Very Dangerous – Acidification of the ocean, destroying coral reefs
and before the end of this century - all calcium carbonate shellbuilding animals, a key base of the food chain on Earth.
• We are in the midst of the 6th Great Extinction – the Anthropocene
Extinction. Half or more of all species of life on Earth are expected to
be extinct by the end of this century. Caused by us, with Global
Warming the single most important cause.
Rising Ocean Concentrations of CO2 and
Dropping pH (Acidification) Clearly
Observed
Worldwide Retreat of Glaciers
What About the Future? IPCC 2007
Predictions are not “Alarmist” Enough – why?
• (1) Greenland ice loss did not model
lubrication of glacier bases by meltwater,
being too poorly understood.
• In fact, Greenland is losing ice much faster
than predicted as this base meltwater
accelerates glaciers into the ocean
Using Observed Greenland Ice Loss Rates – Sea level rise will be 3
times higher than even the IPCC 2007 AR4 Predicted
More Alarming…
• The IPCC 2007 modelling did not include
the effects of Arctic broken ice migrating
out of the Arctic Ocean and into the
warmer Atlantic, which is clearly
accelerating Arctic Ocean ice loss.
• IPCC 2007 expected the Arctic Ocean
would not be ice-free until 2100. We now
expect it’ll be more like 2030. (see graph
on next slide)
And Most Alarming of All…
• Studies show an ice-free Arctic would cause thawing of
permafrost as far as 1500 km south of the Arctic
coastline. This region contains more than twice the entire
carbon content currently in the atmosphere.
• Worse by far, it contains 10 times the methane as is
already in the atmosphere, just in the frozen lakes alone.
These lakes are now melting. (methane is 25x stronger
GHG than CO2)
• If all of this methane is released to the atmosphere, the
Greenhouse Effect heating goes up by 400%. Then add
in further heating due to higher humidity (water vapor is
a power greenhouse gas too), and the above CO2 in
peat, and climate change would be extreme and many
times worse than the most pessimistic IPCC 2007
forecast
• See this video of the arctic lakes methane content
Global Warming is Only a Symptom of a Larger
Problem: Living Beyond the Carrying Capacity of the
Earth
• According to Stanford studies, with current technology,
our planet can support only 1.5-2 billion people
sustainably. We have 7 billion, heading up towards 10
billion.
• Topsoil can only be replaced on geological time scales.
Modern agriculture and land use is causing a loss of 1%
of our topsoil per year
• Our planet today can only sustainably support 7
billion people if they are reduced to a standard of
living equivalent to that in Ethiopia – a place of
widespread grinding poverty. Think about that.
Finally…
• Only 36% of Americans believe that global warming is caused
by human activities, from a Pew poll in 2009 (AGW is far better
understood and accepted in Asia and elsewhere)
• A poorly science-educated public is allowing the fossil fuel industry
and the politicians they influence to commit a great tragedy. Both on
the planet, and our children.
• My opinion, I hope I’m wrong, is that the 21st century will be very
ugly.
• Nolthenius’ First Law – People Learn the
Hard Way
• The scientific studies and journal papers backing up and
expanding on the content of this powerpoint can be found on
my website’s climate page: Click here. I urge you to read it.
• This is your future more than it is mine.