PLEASE NOTE:
*
CCNet CLIMATE SCARES & CLIMATE CHANGE - 28 June 2001
----------------------------------------------------
"It would appear that the climate models have failed again.
Spring
sea ice extent in this region of the Arctic is not experiencing
the rapid
decline they predict to occur as a result of CO2-induced global
warming. In fact, the authors' data suggest that sea ice
conditions
in the Baffin Bay/Labrador Sea region have not yet even emerged
from the
range of natural variability characteristic of the Little Ice
Age! - and
this in the region of the world that is supposed to be the most
sensitive
place on earth to radiative forcing produced by the burning of
fossil
fuels."
-- CO2 Science Magazine, 27 June 2001
"As for slants, well it would be nice if we all knew what
slant
would in the long run turn out to be the healthiest, but for now
the
sceptical material forms a welcome counterpoint to the approved
ozone-holier than thou chorus of the doom merchants. It is quite
difficult
to find much rational discussion elsewhere, let alone to find
balanced
views. After all, every apocalyptic group has its own favourite
flavour of doom mongering and each has its own argument why we
should
devote our attention to earthquake, fire or flood (or indeed to
NEOs, new plagues, or greenhouse immolation) to the effective
exclusion of
rival forms of putative destruction."
--Jon Richfield, 27 June 2001
"Psychological evidence and casual intuition predict that
sunny
weather is associated with upbeat mood. This paper examines the
relation between morning sunshine at a country's leading stock
exchange and market index stock returns that day at 26 stock
exchanges
internationally from 1982-97. Sunshine is strongly positively
correlated
with daily stock returns. After controlling for sunshine, other
weather conditions such as rain and snow are unrelated to
returns. If
transactions costs are assumed to be minor, it is possible to
trade
profitably on the weather. These results are difficult to
reconcile with
fully rational price-setting."
--David Hirshleifer and Tyler Shumway,
http://fisher.osu.edu/fin/dice/papers/2001/2001-3.htm
(1) PENGUINS ON PARADE
Greening Earth Society, 27 June 2001
(2) A STEADY RISE DOES NOT A STEADY RATE MAKE
Greening Earth Society, 26 June 2001
(3) SCIENTISTS RECONCILE OPPOSING VIEWS OF U.S. ROLE IN
GREENHOUSE GAS
PROBLEM
Andrew Yee <ayee@nova.astro.utoronto.ca>
(4) CLIMATE CHANGE AND CORAL REEFS
Andrew Yee <ayee@nova.astro.utoronto.ca>
(5) RARE ORBITAL ANOMALY CAUSED GLOBAL COOLING 23 MILLION YEARS
AGO
Andrew Yee <ayee@nova.astro.utoronto.ca>
(6) A 1000-YEAR RECORD OF SPRING SEA ICE CONDITIONS IN BAFFIN BAY
C02 Science Magazine, 27 June 2001
(7) EFFECTS OF INCREASED ATMOSPHERIC CO2 ON GRASSLAND COMMUNITIES
CO2 Science Magazine, 27 June 2001
(8) MODEL GRASSLAND EFFECTS OF ELEVATED CO2 ON THE NEGEV
CO2 Science Magazine, 27 June 2001
(9) VIEWPOINT: DOES CO2 REALLY DRIVE GLOBAL WARMING?
Chemical Innovation, June 2001
(10) CCNet AND ITS TOPICS
Jon Richfield <richfield@telkomsa.net>
(11) AND FINALLY: GOOD DAY SUNSHINE - STOCK RETURNS AND THE
WEATHER
http://fisher.osu.edu/fin/dice/papers/2001/2001-3.htm
=======
(1) PENGUINS ON PARADE
From Greening Earth Society, 27 June 2001
http://www.greeningearthsociety.org/Articles/2001/vca26.htm
Penguins are in the news again as a host of stories concerning
their plight
flood the popular press. According to Carol Kaesuk Yoon,
reporting in a The
New York Times "Science of the Times" feature on June
26th, "Penguins' best
hope . . . may be their abundant adorability and the protection
and money it
can bring." Who can doubt it. Reportedly 50,000 people a
year flock to see
the penguins at Punta Tombo, a virtual penguin metropolis with a
population
numbered in thousands of birds. They are a tangible asset in
eco-tourism.
Here's a partial list of the hurdles these flightless birds
appear to be
waddling into on their ostensible road to oblivion:
* A wildfire set by wildlife workers in an attempt to burn off
thick grass
near a Fairy penguin breeding ground on Montague Island off
Australia's east
coast got out of control and spread into the colony, killing 42
birds. The
workers were reported to be devastated by the deaths of creatures
they had
studied for years.
* Last summer, an oil spill off South Africa's coast threatened
nearly 40
percent of the African penguin species and killed nearly 2,000 of
the birds.
We note, however, they have since experienced a remarkable
recovery.
* A "freak heat wave" in Antarctica reputedly reduced
the size of an Emperor
penguin colony by 50 percent. We have since demonstrated there to
be no
correlation between the penguin deaths and heat - see
www.greeningearthsociety.org/climate/previous_issues/vol6/v6n18/feature1.htm
.
* King penguins on South Georgia Island apparently fall backwards
as they
watch airplanes and helicopters fly overhead. A researcher
opines, "There
may be an increase in heart rate as helicopters fly over. The
worst possible
effect is that there would be a reduction in their breeding
performance. If
they were incubating eggs this could be quite devastating for
them."
Now, The New York Times reports penguins are in trouble worldwide
because of
global warming - or at least due to climate changes some people
like to
*link* to global warming, things like El Niño and toxic algae
blooms.
A colony of Magellinic and Humbolt penguins, whose primary
nesting ground is
on a narrow peninsula jutting out into the Atlantic Ocean located
near the
southern end of Argentina's east coast called Punta Tombo, is
having a
particularly bad breeding year. "The worst ever," Dr.
Dee Boersma is quoted
as saying. Boersma, a researcher whose work is supported by the
Wildlife
Conservation Society, reports the colony's population has
declined by nearly
30 percent since 1987. Wildlife Conservation Society researchers
blame an
increase in El Niño conditions, despite the fact El Niño
primarily is a
tropical Pacific phenomenon. It has little direct effect in the
southern
Atlantic Ocean. In fact this year (the worst ever, remember) has
been marked
by near normal-conditions. Neither El Niño nor its climatic
doppelgänger La
Niña were present. Nonetheless, researchers appear not be
dissuaded by the
fact that El Niño conditions and global warming never have been
definitively
linked.
Different species of penguins live in a variety of climatic
conditions
throughout the Southern Hemisphere. Their habitat ranges from
Antarctica's
frozen shores to the Galapagos Islands' tropical beaches. This
means
penguins have evolved and adapted to different environments. As
these
environments change - whether due to changes in climate or for
other reasons
- the birds' survival depends upon their continued adaptation.
For example,
warmer conditions on Australia's Heard Island in the southern
Indian Ocean
have led to a virtual explosion of marine life, including an
increase in the
number of King penguin breeding pairs. While there were only
three pairs in
1947, there are more than 25,000, today.
A further demonstration of penguin adaptability can be inferred
from
reconstruction of long-term temperatures in the Southern Atlantic
Ocean
(using paleoclimate reconstructions). Figure 1 shows there to
have been very
large swings in ocean temperature during the past 400,000 years.
Because
penguins exist today, they must have successfully survived those
disruptive
climatic events, which certainly would have dramatically
disrupted the
birds' feeding and breeding patterns if temperature/climate
changes do,
today.
But conspicuously missing from the Times' long litany of things
adversely
affecting penguin populations is any mention of the one
well-known factor
certain to have a human cause: tourism. Perhaps being
"abundantly adorable"
isn't the best defense, after all.
Copyright 2001, Greening Earth Society
==========
(2) A STEADY RISE DOES NOT A STEADY RATE MAKE
From Greening Earth Society, 26 June 2001
http://www.greeningearthsociety.org/Articles/2001/vca25.htm
Humankind's emissions of carbon dioxide are on a steady rise.
CO2's build-up
in our atmosphere takes place at a nearly steady rate. This is
not saying
the same thing two different ways. To say that there has been a
steady
build-up in the concentration of CO2 in the atmosphere over
twenty-five
years implies that more and more CO2 is going someplace other
than our
atmosphere. Take a look at Figure 1
(http://www.greeningearthsociety.org/Articles/2001/vca25.htm).
The vaunted
U.N. Intergovernmental Panel on Climate Change continues to make
assessments
of future climate change based upon climate models that include a
built-in
assumption that the atmosphere's CO2 increase is exponential. As
you can
see, it has not been exponential during the dramatic increase in
CO2
emissions during the last quarter of the 20th century.
Observations instead
show the increase to have been linear.
The implications of this are enormous. Instead of the steady
increase in
global temperatures that climate models produce in assuming an
exponential
increase in CO2 concentration, we are left with a situation where
the
temperature increase slowly damps off once the climate models are
forced
with a linear (rather than exponential) increase in CO2.
This is a consequence of the percentage increase in CO2
concentration slowly
decreasing over time. Therefore its total impact becomes less. By
way of
example, Figure 1b shows how the average growth rate in
atmospheric CO2
concentration has been 1.5 parts per million (ppm) per year over
a span of
twenty-five years. The current concentration of atmospheric CO2
is 369 ppm.
Therefore a change of 1.5 ppm represents a change of 0.41 percent
per year
(1.5/369*100). If we continue along the current trend, by 2100,
the
atmospheric concentration will be 519 ppm. The increase of 1.5
ppm will be
0.29 percent (1.5/519*100).
Now let's compare this with the IPCC's assumptions. In IPCC
scenarios, the
concentration of CO2 in the atmosphere by 2100 ranges from
somewhere around
500 ppm up to1000 ppm. Climate models run with values on the
lower end of
the range (those that observations best support) produce a
warming near the
low end of the IPCC temperature range of 1.4°C to 5.8°C. In
other words,
around 1.5°C. Obviously, the models run with the highest
concentrations
(values that so far are not supported by observations) produce a
much
greater warming.
Which do we hear most about in popular press accounts? Of course,
those that
deviate from reality the most! This in an era of "reality
TV."
But where does the CO2 go if not into the atmosphere? One place
is
terrestrial sinks. It is stored in plants and plant products. Two
papers
published in the June 22nd edition of Science magazine support
this.
The first by Jingyun Fang et al. shows that, since the late
1970s, national
forest expansion and forest re-growth programs in China have
steadily
increased the amount of carbon stored in Chinese forests.
The second paper, reports on research led by Princeton
University's Stephen
Pacala. It appears that U.S. carbon sinks sequester between
one-third and
one-half of U.S. emissions of CO2. Pacala's team carefully
assessed the
amount of carbon stored in eight kinds of terrestrial sinks:
forests trees,
forest organic matter (e.g., downed trees and leaf litter),
agricultural
soil, non-forest and non-cropland growth (shrubby, woody
encroachment), wood
products, river and lake deposits, river discharge, and exported
products.
Pacala's team estimates the total U.S. carbon sink to be a bit
smaller than
that estimated in 1998 by Fan et al. Fan's research team
previously reported
the U.S. carbon sink to be a bit more than half the magnitude of
U.S.
emissions. Pacala's estimate, however, is higher than that
estimated in a
1999 study by Houghton, et al. They estimated the U.S. carbon
sink capable
of offsetting only about one-tenth to one-fifth of our emissions.
Regardless of the actual value (which varies from year to year in
any case),
Pacala's study confirms the U.S. terrestrial carbon sink to be
quite large.
While the team did not find evidence that the U.S. sink is
growing (as it is
in China), neither did they find it to be shrinking. They report
that
results from 1980-1989 are "similar to those for 1985-1989
and 1990-1994,
indicating a relatively stable U.S. sink throughout the
period."
Taken together, these results indicate a large and growing
terrestrial
carbon sink that acts to reduce the build-up of atmospheric
carbon dioxide
and ameliorate future temperature increases.
References
Fan, S., et al.,1998. A Large Terrestrial Carbon Sink in North
America
Implied by Atmospheric and Oceanic Carbon Dioxide Data and
Models. Science,
282:442-446.
Fang, J., et al., 2001. Changes in Forest Biomass Carbon Storage
in China
Between 1949 and 1998. Science, 292:2320-2322.
Houghton R.A., Hackler, J.L., and K.T. Lawrence, 1999. The U.S.
Carbon
Budget: Contributions from Land-Use Change. Science, 285:574-578.
Pacala, S.W., et al., 2001. Consistent Land- and Atmosphere-Based
U.S.
Carbon Sink Estimates. Science, 292:2316-2320.
Figure 1a (top): The annual global emissions of carbon dioxide
have been
steadily increasing, but as shown in Figure 1b (bottom) the
growth rate of
the atmospheric carbon dioxide concentration has been steady for
the past 25
years. This means that more and more, carbon dioxide must be
ending up
somewhere other than in the atmosphere.
===========
(3) SCIENTISTS RECONCILE OPPOSING VIEWS OF U.S. ROLE IN
GREENHOUSE GAS
PROBLEM
From Andrew Yee <ayee@nova.astro.utoronto.ca>
News from PRINCETON UNIVERSITY
Office of Communications
Stanhope Hall
Princeton, New Jersey 08544-5264
Telephone 609-258-3601; Fax 609-258-1301
Contact:
Steven Schultz (609) 258-5729, sschultz@princeton.edu
Embargoed for release: 2 p.m. EDT, June 21, 2001
Scientists reconcile opposing views of U.S. role in greenhouse
gas problem
Princeton, N.J. -- An international consortium of scientists has
issued a
revised estimate of the U.S. role in the worldwide accumulation
of carbon
dioxide in the atmosphere, a major cause of global warming.
The study, published in the June 22 issue of Science, reconciles
what had
appeared to be sharply conflicting measurements about the size of
the U.S.
"carbon sink" -- an effect that drains carbon from the
air and stores it in
the land.
The Princeton University-led research group found that the
continental
United States is currently absorbing one-third to two-thirds of a
billion
metric tons of carbon per year. The main reason is that U.S.
trees and
shrubs, which are recovering from past clearing, are drawing
great volumes
of carbon dioxide from the air and using the carbon to build
massive tree
trunks, branches and foliage. The suppression of natural forest
fires also
is causing an increase in vegetation.
The study is the work of 23 scientists who initially held
strongly differing
views about the size of the carbon sink. At the center of the
dispute was
the method of measuring the sink. One approach is to take samples
directly
from the atmosphere and estimate gains and losses of carbon
dioxide as winds
blow across the country. This strategy has yielded widely varying
answers
depending on the exact method used. Another approach is to
inventory the
myriad places carbon can accumulate in the land -- including
trees, soils,
landfills and reservoirs -- and estimate how that inventory is
changing over
time. This land-based approach gave very small estimates for the
carbon
sink, but none accounted for all the places carbon accumulates.
In 1998, a Princeton-led group published a paper using
atmospheric data to
estimate that southern Canada, the 48 states and Mexico
collectively absorb
1.4 billion tons of carbon per year. That conclusion triggered
strong
criticism from scientists who believed it was an inflated figure.
The new study reconciles previous differences by including 27
different
atmospheric methods and by performing an exhaustive land-based
analysis. The
scientists also took special care to base their calculations on
the same
time period and the same geographic region, focusing exclusively
on the 48
states in the years 1980 to 1989. Through this process, the
researchers
found that the atmosphere- and land-based assessments actually
agree with
each other, within the margins of uncertainty of each method. The
final
answer of one-third to two-thirds of a billion tons per year is
lower than
the controversial 1998 result, but higher than all earlier
land-based
estimates and some previous atmospheric estimates.
Despite the large U.S. carbon sink, the nation still pumps a
tremendous
amount of carbon into the atmosphere. The burning of fossil fuels
in the
United States releases about 1.4 billion tons of carbon each
year. Taking
into account the carbon sink, 800 million to 1.1 billion tons
accumulate in
the atmosphere annually. The new analysis eliminates the
possibility that
the U.S carbon sink is big enough to equal the U.S. fossil fuel
release, as
some had speculated following the 1998 study.
Princeton's Stephen Pacala, the lead author of the new study,
emphasized
that the carbon sink should not be seen as offsetting the U.S.
carbon
emissions from fossil fuels, and should not be viewed as a
license to
release more carbon. A large part of the sink is merely the
result of the
land taking back enormous quantities of carbon that were released
due to
heavy farming and logging in the 19th and early 20th centuries.
"When we chopped down the forests, we released carbon
trapped in the trees
into the atmosphere. When we plowed up the prairies, we released
carbon from
the grasslands and soils into the atmosphere," said Pacala,
who is a
professor of ecology and evolutionary biology. "Now the
ecosystem is taking
some of that back."
The sink will disappear over the next 50 to 100 years as U.S.
ecosystems
complete their recovery from past land use, Pacala said.
"The carbon sinks
are going to decrease at the same time as our fossil fuel
emissions
increase," Pacala said. "Thus the greenhouse problem is
going to get worse
faster than we expected."
The problem is similar worldwide. Globally, the use of fossil
fuels pumps
6.3 billion tons of carbon into the atmosphere each year. Another
1.6
billion tons are estimated to be released due to the widespread
loss of
forestland in some parts of the world. However, the oceans and
land-based
carbon sinks, such as the North American sink, absorb a large
amount of
carbon, leaving just over three billion tons to accumulate in the
atmosphere
each year. As U.S. and other carbon sinks mature and disappear,
that rate of
accumulation will increase dramatically.
There is some interplay between the U.S. carbon sink and
emissions in other
parts of the world. The study found that the United States
absorbs 370 to
710 million tons of carbon each year, but 70 to 130 million tons
of this are
exported to other parts of the globe in the form of grain and
other
agricultural products and are released back into the atmosphere
elsewhere
when those products are used. Thus the total impact of the U.S.
sink on
worldwide carbon absorption is the removal of 300 to 580 million
tons of
carbon per year.
In addition to Princeton scientists, the Science paper includes
authors from
the University of New Hampshire, the French national research lab
CNRS, the
Woods Hole Research Center, the U.S. Forest Service, the U.S.
Geological
Survey, the Johann Wolfgang Goethe-Universitaet in Frankfurt,
Germany, the
Max Planck Institute for Biogeochemistry in Jena, Germany, Oregon
State
University and the Carnegie Institution of Washington in
Stanford, Calif.
=============
(4) CLIMATE CHANGE AND CORAL REEFS
From Andrew Yee <ayee@nova.astro.utoronto.ca>
Geological Society of America
Boulder, Colorado
Contact:
Ann Cairns, Director-Communications
acairns@geosociety.org,
303-447-2020, ext. 1156
June 21, 2001
GSA Release No. 01-32
Climate Change And Coral Reefs
Corals are famously sensitive to their environment, but their
fate may be
determined in the coming century by the relative rates and timing
of sea
level rise, global warming and other anthropogenic impacts.
Disentangling
these effects is a complex problem.
Corals can only grow within a very narrow window of ecological
conditions,
determined by depth, temperature and salinity. If sea levels rise
more
quickly than their slow growth can accommodate, they will die.
They are also
sensitive to predation and to marine pollution.
Coral reefs are in decline. Coral cover has shrunk by at least
30% in the
last 30 years, and in some places (e.g., the Caribbean) by as
much as 90%.
Climatic stresses, such as cyclones, together with unusually warm
ocean
temperatures, high nutrient loads from soil erosion and
fertilizers, are
proving a lethal combination.
In 1997-98, unusually warm temperatures led to widespread coral
bleaching
and reef degradation worldwide, compounded by the fact that many
reefs could
not regenerate due to algal blooms created by high nutrient
levels. Coral
bleaching is predicted to rise as a result of continued global
warming,
while calcification rates will fall due to higher atmospheric
concentrations
of carbon dioxide (from fossil fuel burning).
However, the adaptability of coral reefs is often underestimated,
says
Malcolm McCulloch (Australian School of Earth Sciences,
Canberra), who
presents his research at Earth System processes, a
multidisciplinary
conference organised by the Geological Society of London (GSL)
and the
Geological Society of America (GSA).
"Looking back over longer timescales, we know that extreme
variations in
climate have occurred in the past" says McCulloch. "In
only the last 500,000
years, we know that there were interglacial stages when
conditions were
warmer than today, and which persisted for longer. Multiple
oscillations of
sea level occurred during Marine Isotope Stage (MIS) 9 (c.320,000
years ago)
and during the last interglacial, sea levels were between four
and five
metres higher than today. Coral growth during these periods was
especially
prolific, because the rising sea levels provided more space for
corals to
grow into, while the warmer oceans opened up larger areas to
coral
colonization.
"The problem that coral reefs face today is the two-pronged
attack by
anthropogenic pollution combined with global warming. The
combined effects
on the world's already highly stressed coral reefs may well be
terminal.
"So in theory although warmer seas and rising sea levels
could be good for
corals -- it's all a matter of timing. They could do well in a
warmer world
-- as long as the rate of warming is no faster than they can cope
with, and
assuming they our pollution doesn't kill them off first".
CONTACT INFORMATION
During the Earth System Processes meeting, June 25-28, contact
the GSA/GSL
Newsroom at the Edinburgh International Conference Centre for
assistance and
to arrange for interviews: +44 (0) 131 519 4134
Ted Nield, GSL Science and Communications Officer
Ann Cairns, GSA Director of Communications
The abstract for this presentation is available at:
http://gsa.confex.com/gsa/2001ESP/finalprogram/abstract_8134.htm
Post-meeting contact information:
Malcolm McCulloch
Research School of Earth Sciences
Australian National University
Canberra, Australia
Malcolm.mcculloch@anu.edu.au
Ted Nield
Geological Society of London
+44 (0) 20 7434 9944
ted.nield@geolsoc.org.uk
Ann Cairns
Geological Society of America
+01 303 447 2020 ext. 1156
acairns@geosociety.org
==========
(5) RARE ORBITAL ANOMALY CAUSED GLOBAL COOLING 23 MILLION YEARS
AGO
From Andrew Yee <ayee@nova.astro.utoronto.ca>
Geological Society of America
Boulder, Colorado
Contact:
Ann Cairns, Director-Communications
acairns@geosociety.org,
303-447-2020, ext. 1156
June 21, 2001
GSA Release No. 01-30
Wheels Within Wheels: Rare Orbital Anomaly May Have Caused Global
Cooling 23
Million Years Ago
A rare coincidence of orbital cycles may have caused sudden
global cooling
23 million years (Ma) ago, according to scientists, who used high
resolution
records and new techniques that allow astronomical calibration to
be
extended much further back in time.
The late Oligocene to early Miocene Earth (20-26 Ma ago)
experienced a
complex climate history, including a stepwise transition towards
cooler
climate, with partial glaciations of the Antarctica. At the
boundary between
the two periods, scientists have also discovered a blip in
isotope records
that could only have been caused by a short but expansive
glaciation of
Antarctica, coupled with several degrees of sea cooling. The
question is --
what caused these climatic excursions?
Using information from Ocean Drilling Project (ODP) sites 926 and
929
(western equatorial Atlantic), the team of US and UK scientists
has put
together an uninterrupted and high-fidelity chronology of
Oligocene and
early Miocene isotope geochemistry that enables them to
reconstruct the
climatic conditions of that time. Results of their work will be
shared at
the Earth Systems
Processes conference on Wednesday, June 27, in Edinburgh,
Scotland. The
Geological Society of America and the Geological Society of
London will
co-convene the June 24-28 meeting.
The Earth's climate varies in a cyclic manner first defined by
the scientist
after whom the cycles are named, Milutin Milankovitch. The cores
studied
show persistent periodic climatic variations as the Milankovitch
theory
would suggest. However there were unusually strong signals where
the
variability in isotope signals increased considerably -- between
21.4 and
22.9 Ma ago, and weaker signals where the isotope signal
decreased --
between 22.9 and 23.3 Ma ago.
Astronomical calculations suggest that over this 0.4 million-year
period
there were four consecutive cycles involving low amplitude
variance in
orbital obliquity (the inclination of the Earth's orbit to the
plane of the
ecliptic) during a period of low orbital eccentricity (relatively
less
elliptical orbits). The net result of this was a 200,000-year
period of
unusually low seasonality. This, the researchers believe, could
have been
responsible for
the step-like growth of the Antarctic ice-sheet at the time, and
the
prolonged period of cooling.
Lead Author James Zachos (University of California, Santa Cruz)
said "This
unique isotope record provides a rare window into how the climate
system
responded to orbital forcing during the Earth's more distant
past."
CONTACT INFORMATION
During the Earth System Processes meeting, June 25-28, contact
the GSA/GSL
Newsroom at the Edinburgh International Conference Centre for
assistance and
to arrange for interviews: +44 (0) 131 519 4134
Ted Nield, GSL Science and Communications Officer
Ann Cairns, GSA Director of Communications
The abstract for this presentation is available at:
http://gsa.confex.com/gsa/2001ESP/finalprogram/abstract_7838.htm
Post-meeting contact information:
James Zachos
Earth Sciences
University of California, Santa Cruz
Santa Cruz, CA 95054 USA
+01 (0) 831 459 4644
jzachos@es.ucsc.edu
Ted Nield
Geological Society of London
+44 (0) 20 7434 9944
ted.nield@geolsoc.org.uk
Ann Cairns
Geological Society of America
+01 303 447 2020 ext. 1156
acairns@geosociety.org
==========
(6) A 1000-YEAR RECORD OF SPRING SEA ICE CONDITIONS IN BAFFIN BAY
From C02 Science Magazine, 27 June 2001
http://www.co2science.org/journal/2001/v4n26c1.htm
Reference
Grumet, N.S., Wake, C.P., Mayewski, P.A., Zielinski, G.A.,
Whitlow, S.L.,
Koerner, R.M., Fisher, D.A. and Woollett, J.M. 2001. Variability
of sea-ice
extent in Baffin Bay over the last millennium. Climatic
Change 49: 129-145.
What was done
Recent trends in polar sea ice cover, according to the authors,
"can be
viewed out of context because their brevity does not account for
interdecadal variability, nor are the records sufficiently long
to clearly
establish a climate trend." Hence, they developed a
1000-year record of
spring sea ice conditions in the Arctic region of Baffin Bay,
using sea-salt
records from an ice core obtained from the Penny Ice Cap on
Baffin Island.
What was learned
A statistically significant shift in sea-ice conditions in the
Penny Ice Cap
record was noted to occur around 1420 AD, such that enhanced sea
ice
conditions have prevailed in this region of the Arctic during the
past 600
years, as opposed to the reduced sea-ice conditions
characteristic of the
11th through 14th centuries. As for the past 100 years, the
authors note
that "despite warmer temperatures during the turn of the
century, sea-ice
conditions in the Baffin Bay/Labrador Sea region, at least during
the last
50 years, are within 'Little Ice Age' variability."
What it means
It would appear that the climate models have failed again.
Spring sea ice
extent in this region of the Arctic is not experiencing the rapid
decline
they predict to occur as a result of CO2-induced global
warming. In fact,
the authors' data suggest that sea ice conditions in the Baffin
Bay/Labrador
Sea region have not yet even emerged from the range of natural
variability
characteristic of the Little Ice Age! - and this in the region of
the world
that is supposed to be the most sensitive place on earth to
radiative
forcing produced by the burning of fossil fuels!!
Copyright © 2001. Center for the Study of Carbon Dioxide
and Global Change
==========
(7) EFFECTS OF INCREASED ATMOSPHERIC CO2 ON GRASSLAND COMMUNITIES
From CO2 Science Magazine, 27 June 2001
http://www.co2science.org/subject/g/summaries/grasslandswholecom.htm
Grasslands (Biomass - Whole Communities) -- Summary
As the CO2 content of the air increases, plants exhibit
modifications in
their physiology. One common change is increased photosynthesis.
With
greater amounts of CO2 in the air - and greater amounts of CO2
thus
diffusing into leaves - the primary carboxylating enzyme of most
plants,
i.e. rubisco, performs its biochemical functions more
efficiently, leading
to reductions in photorespiratory carbon losses and increases in
carbohydrate synthesis; and with additional carbohydrate
production, most
plants exhibit enhanced rates of growth and biomass
accumulation. In this
summary we thus review the effects of elevated atmospheric CO2
concentrations on biomass production in grassland communities.
Navas et al. (1999) grew mixed communities of two grasses and two
legumes
across a range of soil nitrogen contents at ambient (357ppm) and
enriched
(712 ppm) atmospheric CO2 concentrations for a period of two
months.
Although soil nitrogen content had a much greater influence on
community
productivity than did atmospheric CO2 concentration, communities
fumigated
with CO2-enriched air tended to produce greater amounts of
biomass than
communities exposed to ambient air. Likewise, Jongen and
Jones (1998)
reported that an eight-month exposure to twice-ambient levels of
atmospheric
CO2 increased the community biomass of semi-natural grasslands
characteristic of the Irish lowlands by 26%.
In a dual study investigating the responses of a species-rich
turf growing
over limestone and a species-poor turf growing over a peaty soil,
Fitter et
al. (1997) noted that enriching the air with an additional 250
ppm CO2 had
no effect on shoot biomass production in either monolith after
two years of
fumigation. However, atmospheric CO2 enrichment
significantly stimulated
root biomass production by 40 to 50% in both grassland
ecosystems.
In the two-year study of Stocklin et al. (1999), simulated low
fertility
Swiss grasslands were grown in glasshouses receiving atmospheric
CO2
concentrations of 360 and 600 ppm, with the authors determining
that
elevated CO2 concentrations stimulated total biomass production
by an
average of 23% in these nutrient poor grassland
communities. And in yet
another two-year experiment, Niklaus et al. (1998) noted that
swards of
calcareous grasslands exposed to atmospheric CO2 concentrations
of 600 ppm
displayed total biomass values that were 25% greater than those
exhibited by
control swards grown in ambient air of 350 ppm CO2.
After growing microcosms of the C3 grass Danthonia richardsonii
for four
years in glasshouses receiving atmospheric CO2 concentrations of
360 and 720
ppm, Lutze and Gifford (1998) reported the elevated CO2 increased
total
microcosm biomass by an average of 24%. Similarly, in the
four-year study
of Leadley et al. (1999), species-rich Swiss grasslands exposed
to
atmospheric CO2 concentrations of 600 ppm in open-top and
open-bottom
chambers produced 29% more community biomass than control
grasslands exposed
to air of 350 ppm CO2. And in the longest CO2-enrichment
study of grassland
communities to date - lasting eight complete years - it was
reported that
tallgrass prairie ecosystems in Kansas, USA, exposed to
twice-ambient levels
of atmospheric CO2 displayed significant CO2-induced enhancements
of
biomass, but only during relatively dry years (Owensby et al.,
1999).
A good summary of grassland community biomass responses to
atmospheric CO2
enrichment can be found in the comprehensive review of Campbell
et al.
(2000), who compiled and analyzed over 165 peer-reviewed
scientific journal
articles dealing with pastures and rangelands. Although their
review
included many responses of individual species, it provides a
conservative
estimate of community responses as well: an average 17% increase
for a
doubling of the air's CO2 content. Hence, as the
atmospheric CO2
concentration continues to increase, it is likely that grassland
communities
will respond by exhibiting increases in photosynthesis and
biomass
production, which will invariably lead to enhanced carbon
sequestration in
the soils beneath them.
References
Campbell, B.D., Stafford Smith, D.M., Ash, A.J., Fuhrer, J.,
Gifford, R.M.,
Hiernaux, P., Howden, S.M., Jones, M.B., Ludwig, J.A.,
Manderscheid, R.,
Morgan, J.A., Newton, P.C.D., Nosberger, J., Owensby, C.E.,
Soussana, J.F.,
Tuba, Z. and ZuoZhong, C. 2000. A synthesis of recent
global change
research on pasture and rangeland production: reduced
uncertainties and
their management implications. Agriculture, Ecosystems and
Environment 82:
39-55.
Fitter, A.H., Graves, J.D., Wolfenden, J., Self, G.K., Brown,
T.K., Bogie,
D. and Mansfield, T.A. 1997. Root production and
turnover and carbon
budgets of two contrasting grasslands under ambient and elevated
atmospheric
carbon dioxide concentrations. New Phytologist 137:
247-255.
Jongen, M. and Jones, M.B. 1998. Effects of elevated
carbon dioxide on
plant biomass production and competition in a simulated neutral
grassland
community. Annals of Botany 82: 111-123.
Leadley, P.W., Niklaus, P.A., Stocker, R. and Korner, C.
1999. A field
study of the effects of elevated CO2 on plant biomass and
community
structure in a calcareous grassland. Oecologia 118: 39-49.
Lutze, J.L. and Gifford, R.M. 1998. Carbon
accumulation, distribution and
water use of Danthonia richardsonii swards in response to CO2 and
nitrogen
supply over four years of growth. Global Change Biology 4:
851-861.
Navas, M.-L., Garnier, E., Austin, M.P. and Gifford, R.M.
1999. Effect of
competition on the responses of grasses and legumes to elevated
atmospheric
CO2 along a nitrogen gradient: differences between isolated
plants,
monocultures and multi-species mixtures. New Phytologist
143: 323-331.
Niklaus, P.A., Leadley, P.W., Stocklin, J. and Korner, C.
1998. Nutrient
relations in calcareous grassland under elevated CO2.
Oecologia 116: 67-75.
Owensby, C.E., Ham, J.M., Knapp, A.K. and Auen, L.M.
1999. Biomass
production and species composition change in a tallgrass prairie
ecosystem
after long-term exposure to elevated atmospheric CO2.
Global Change Biology
5: 497-506.
Stocklin, J. and Korner, Ch. 1999. Interactive
effects of elevated CO2, P
availability and legume presence on calcareous grassland: results
of a
glasshouse experiment. Functional Ecology 13: 200-209.
Copyright © 2001. Center for the Study of Carbon Dioxide
and Global Change
========
(8) MODEL GRASSLAND EFFECTS OF ELEVATED CO2 ON THE NEGEV
From CO2 Science Magazine, 27 June 2001
http://www.co2science.org/journal/2001/v4n26b2.htm
Effects of Elevated CO2 on Model Grasslands of the Semi-arid
Negev of Israel
Reference
Grunzweig, J.M. and Korner, C. 2001. Growth, water
and nitrogen relations
in grassland model ecosystems of the semi-arid Negev of Israel
exposed to
elevated CO2. Oecologia (on-line).
What was done
The authors constructed model grasslands representative of the
Negev of
Israel and placed them in growth chambers with atmospheric CO2
concentrations of 280, 440 and 600 ppm for five months to
determine the
effects of elevated CO2 on these semi-arid plant communities.
What was learned
Elevated CO2 reduced rates of evapotranspiration and increased
soil moisture
contents in model grassland communities exposed to atmospheric
CO2
concentrations of 440 and 600 ppm. Between two periods of
imposed drought,
for example, soil moisture was 22 and 27% higher in communities
exposed to
440 and 600 ppm CO2, respectively, than it was in control
communities
exposed to pre-industrial levels of atmospheric CO2. Such
increases in soil
moisture content possibly contributed to peak ecosystem CO2
uptake rates
that were 21 and 31% greater at 400 and 600 ppm CO2 than they
were at 280
ppm CO2. In addition, atmospheric CO2 enrichment had no
effect on nighttime
respiratory carbon losses from the ecosystems. Thus, these
semi-arid
grasslands were acting as carbon sinks under CO2-enriched
conditions. In
fact, elevated CO2 (440 and 600 ppm) increased total community
biomass by
14% over that produced by communities exposed to the subambient
CO2
concentration. Also, when the total biomass produced was
related to the
total amount of water loss via evapotranspiration, communities
grown at
atmospheric CO2 concentrations of 440 and 600 ppm exhibited
CO2-induced
increases in water-use efficiency that were 17 and 28% higher
than those
displayed by control communities exposed to air of 280 ppm CO2.
What it means
As the atmospheric CO2 concentration increases, semi-arid
grasslands common
to the Negev of Israel will likely exhibit increases in
photosynthesis and
biomass production. Moreover, such increases in biomass
will likely occur
while using less water. Indeed, model ecosystems exposed to
elevated
atmospheric CO2 concentrations lost less water through
evapotranspiration
and consequently had greater soil moisture contents than
ecosystems that
were not CO2-enriched. Hence, one would anticipate that the
water-use
efficiencies of these grasslands will likely increase in future
years with
further increases in the air's CO2 content. Most
importantly, the gas
exchange measurements - including the null effect of elevated CO2
on dark
respiration - and the biomass data obtained for the ecosystems
demonstrate
that these grasslands will likely become ever stronger carbon
sinks that
remove ever greater amounts of carbon from the air as time
progresses.
Copyright © 2001. Center for the Study of Carbon Dioxide
and Global Change
=======
(9) VIEWPOINT: DOES CO2 REALLY DRIVE GLOBAL WARMING?
From Chemical Innovation, June 2001
http://pubs.acs.org/subscribe/journals/ci/31/special/may01_viewpoint.html.
Does CO2 really drive global warming?
By Professor Robert H. Essenhigh
I don't believe that it does.
To the contrary, if you apply the IFF test-if-and-only-if or
necessary-and-sufficient-the outcome would appear to be exactly
the reverse.
Rather than the rising levels of carbon dioxide driving up the
temperature,
the logical conclusion is that it is the rising temperature that
is driving
up the CO2 level. Of course, this raises a raft of questions, but
they are
all answerable. What is particularly critical is distinguishing
between the
observed phenomenon, or the "what", from the governing
mechanism, or the
"why". Confusion between these two would appear to be
the source of much of
the noise in the global warming debate.
In applying the IFF test, we can start with the clear correlation
between
the global CO2 profile and the corresponding temperature
signature. There is
now in the literature the report of a 400,000-year sequence
clearly showing,
as a phenomenon, that they go up-and down-together (1). The
correlation is
clear and accepted. But the causation, the mechanism, is
something else:
Which is driving which?
FULL ARTICLE at
http://pubs.acs.org/subscribe/journals/ci/31/special/may01_viewpoint.html.
============================
* LETTERS TO THE MODERATOR *
============================
(10) CCNet AND ITS TOPICS
From Jon Richfield <richfield@telkomsa.net>
Hi Benny,
Inured as I am to less specialist forums, I am somewhat bemused
by the
occasional complaints of off-topic material and excessive
attention to
non-NEO discussion. I reckon that the trouble you take to provide
a table of
contents and message titles renders it very easy to skim
CCNet
email and ignore matters of limited personal interest.
Segregating the email
into issues as you do, makes selective reading even easier. Also,
however
interesting and important NEOs are (they certainly interest me
and I regard
them as vitally [adverb chosen aforethought and not as
convenient cliché] important) they are not the only interesting
and
important material. I consider the mix of subject matter pretty
OK, all
things considered.
Furthermore, as Charles Petit surely realises (CCNet, 18/06/01),
one cannot
legislate the frequency and slant of news reports. CO2 is
flavour of the
month and until the media choke on it there will be a surfeit.
Thereafter it
will sink without a trace till the next politically correct
scare. Of
course not all the sounding off is seminal, but that is the
nature of the
game. Even if we did vet every report to sift out the
dispensable bits, we
could be sure that there would be disagreement on inclusion and
rejection.
Easiest to let the readers choose which items in the table of
contents to
seek out for themselves.
As for slants, well it would be nice if we all knew what slant
would in the
long run turn out to be the healthiest, but for now the sceptical
material
forms a welcome counterpoint to the approved ozone-holier than
thou chorus
of the doom merchants. It is quite difficult to find much
rational
discussion elsewhere, let alone to find balanced views. After
all, every
apocalyptic group has its own favourite flavour of doom mongering
and each
has its own argument why we should devote our attention to
earthquake, fire
or flood (or indeed to NEOs, new plagues, or greenhouse
immolation) to the
effective exclusion of rival forms of putative destruction.
In short (by my standards) I like your selection of material and
hope you
stick more or less to the current policy. I do take Charles
Petit's point
and it would be just lovely to have a forum neatly split into
special
interest groups, but to maintain any forum of the type is a
full-time job
and we all know that you have a professional life of your own to
deal with.
Many thanks
And, while I have your ear, one thing that I have been wondering
is the
actual significance of CO2 greenhousing. CO2 absorbs IR in
a couple of
fairly narrow bands and does so on an exponential basis (if we
doubled the
concentration in the air, it would not double the absorption, but
square the
fraction of unabsorbed energy, and then only in those
bands.) Could anyone
in the group who is expert in the subject matter please comment:
1 How much IR in the relevant windows is getting through the CO2
already in
the atmosphere?
2 What fraction of the trapped solar energy is in those IR
absorption
frequencies?
Surely if only a small fraction is getting through, then adding
more CO2
would have little effect? Surely if those windows pass only a
modest
fraction of the re-radiated solar energy, then CO2 is not the gas
we should
be worrying about?
More generally, is there anywhere on the WWW a list or a review
discussion
that puts the various gases, such as H2O, CO2, CH4, O3, CFCs,
other VOCs,
Nox and SOx into perspective in terms of relevant variables such
as:
· What fraction of the range of frequencies of radiant energy
they absorb
· How strongly they absorb the energy in their respective
windows
· What the effect of increasing each absorber would be
· What the capacity for increased concentration of each absorber
might be
(One cannot increase some of them without their getting rained
out or decomposed.)
· What the effect of the absorption would be (whether excluding
the incoming
energy or trapping the absorbed energy)
· Whether the dominant states of the respective compounds in the
atmosphere
have one effect or the contrary effect (for instance, H2O in the
form of cloud reflects
incoming heat, but as a gas it is an absorber. NOx and SOx in
combination with H2O would be even
stronger reflectors and absorbers, at a guess.)
No doubt I am being simplistic, but I don't see how we can expect
to get any
meaningful discussion as long as the debate ignores such factors
in
combination. If there is no such review document accessible
on the WWW,
then is there anyone in this forum who has the skills and the
resources to
prepare one?
I would see something of the sort as a most valuable contribution
and would
leap at the opportunity to produce it myself, except that in such
matters I
am hopelessly incompetent. Such a project would require
specific skills and
knowledge rather than hand-waving.
As a good deal of the relevant material is still under assessment
and the
implications are still open to discussion, if anyone produced a
review as a
live document, frequently updated and open to discussion, and
CCNet kept it
accessible, that would be a valuable public service if there is
nothing of
the type available elsewhere.
Thanks for your attention,
Jon Richfield
========
(11) AND FINALLY: STOCK RETURNS AND THE WEATHER
From http://fisher.osu.edu/fin/dice/papers/2001/2001-3.htm
Good Day Sunshine: Stock Returns and the Weather
David Hirshleifer and Tyler Shumway
ABSTRACT
Psychological evidence and casual intuition predict that sunny
weather is
associated with upbeat mood. This paper examines the relation
between
morning sunshine at a country's leading stock exchange and market
index
stock returns that day at 26 stock exchanges internationally from
1982-97.
Sunshine is strongly positively correlated with daily stock
returns. After
controlling for sunshine, other weather conditions such as rain
and snow are
unrelated to returns. If transactions costs are assumed to be
minor, it is
possible to trade profitably on the weather. These results are
difficult to
reconcile with fully rational price-setting.
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