Download Aff Ice Age DA 7WK - Open Evidence Archive

****AFFIRMATIVE SECTION****
Warming Causes Ice Age – Empirics
Warming causes an ice age – Younger Dryas period proves
Stipp 4 (David senior writer for Fortune and a former staff reporter for the Wall Street Journal, where he covered science, medicine, and technology,
“The Pentagon's Weather Nightmare The climate could change radically, and fast. That would be the mother of all national security issues,” 2/9/04,
CNN, http://money.cnn.com/magazines/fortune/fortune_archive/2004/02/09/360120/index.htm)
(FORTUNE Magazine) – Global warming may be bad news for future generations, but let's face it, most of us spend as little time worrying about it as we
did about al Qaeda before 9/11. Like the terrorists, though, the seemingly remote climate risk may hit home sooner and harder than we ever imagined. In
fact, the prospect has become so real that the Pentagon's strategic planners are grappling with it. The threat that has riveted their attention is this: Global
warming, rather than causing gradual, centuries-spanning change, may be pushing the climate to a tipping point. Growing evidence suggests the
ocean-atmosphere system that controls the world's climate can lurch from one state to another in less than a
decade--like a canoe that's gradually tilted until suddenly it flips over. Scientists don't know how close the system is to a critical
threshold. But abrupt climate change may well occur in the not-too-distant future. If it does, the need to rapidly adapt may
overwhelm many societies--thereby upsetting the geopolitical balance of power. Though triggered by warming, such change would
probably cause cooling in the Northern Hemisphere, leading to longer, harsher winters in much of the U.S. and Europe.
Worse, it would cause massive droughts, turning farmland to dust bowls and forests to ashes . Picture last fall's
California wildfires as a regular thing. Or imagine similar disasters destabilizing nuclear powers such as Pakistan or
Russia--it's easy to see why the Pentagon has become interested in abrupt climate change. Climate researchers began
getting seriously concerned about it a decade ago, after studying temperature indicators embedded in ancient layers of Arctic ice. The data show that a
number of dramatic shifts in average temperature took place in the past with shocking speed--in some cases, just a few years. The case for angst was
buttressed by a theory regarded as the most likely explanation for the abrupt changes. The eastern U.S. and northern Europe, it seems,
are warmed by a huge Atlantic Ocean current that flows north from the tropics--that's why Britain, at Labrador's latitude, is
relatively temperate. Pumping out warm, moist air, this "great conveyor" current gets cooler and denser as it moves
north. That causes the current to sink in the North Atlantic, where it heads south again in the ocean depths.
The sinking process draws more water from the south, keeping the roughly circular current on the go . But when
the climate warms, according to the theory, fresh water from melting Arctic glaciers flows into the North Atlantic,
lowering the current's salinity--and its density and tendency to sink. A warmer climate also increases rainfall and runoff into
the current, further lowering its saltiness. As a result, the conveyor loses its main motive force and can rapidly collapse,
turning off the huge heat pump and altering the climate over much of the Northern Hemisphere. Scientists aren't sure what caused the warming that
triggered such collapses in the remote past. (Clearly it wasn't humans and their factories.) But the data from Arctic ice and other sources suggest the
atmospheric changes that preceded earlier collapses were dismayingly similar to today's global warming. As the Ice Age began drawing to
a
close about 13,000 years ago, for example, temperatures in Greenland rose to levels near those of recent decades. Then they abruptly plunged
as the conveyor apparently shut down, ushering in the "Younger Dryas" period , a 1,300-year reversion to ice-age
conditions. (A dryas is an Arctic flower that flourished in Europe at the time.)
Warming Causes Ice Age - Conveyor Belt Reverse
Warming flips ice age – it would stop the ocean conveyor belt
Williams 2 (David, Writer for the Seattle Times, “UW professor's new book warns of global warming's evil , icy twin,” 5/17/2,
http://infoweb.newsbank.com.proxy.lib.umich.edu/iwsearch/we/InfoWeb?p_product=AWNB&p_theme=aggregated5&p_action=doc&p_docid=0F94CA9D87BB0051&p_docnum=1&p_queryname=1)
Despite what our president, a few scientists, oil-company spokesmen and the Big Three automakers say, global warming is here. This is not a new story.
Anyone who has paid attention knows that global warming could have drastic effects. What most stories fail to report is
that many researchers are less concerned by global warming than by its evil twin : immediate and dramatic
cooling, which could lead to a catastrophic ice age that could take over the globe. Such a rapid cooling, although a
relatively new news story, is not an unusual event in Earth's history. Abrupt climate change has occurred scores of times in just the past
2.5 million years, a period that corresponds with critical evolutionary events in our ancestors' history. We may understandably fear these shifts, but
without them our species might not exist, or so writes William H. Calvin in his newest book , "A Brain for All Seasons." A professor of psychiatry and
behavioral sciences at the University of Washington, Calvin focuses his research on the brain, and in particular our species. His previous books include
"Lingua ex Machina," "The River That Flows Uphill," and "How Brains Think." "A Brain for All Seasons" grew out of his January 1998 article, "The Great
Climate Flip-Flop," in The Atlantic Monthly. Calvin's basic premise is that climatic flip-flops from warm and wet to cold and dry
have happened often, every few thousand years, and appeared quicKLy, in less than a decade. They have led to
widespread fires and extensive drought, exacerbated by severe windstorms. The resulting devastation caused
population crashes of many species, including our ancestors. A few survived, however, only to have their descendants go through
the process over and over again. One of the consequences of such whiplash changes in climate and population is that hominid survivors learned to adapt
to eating grass, a key post-inferno colonizer. They didn't necessarily actually eat the grass but did consume those who consumed grass, the big grazing
animals that survived the droughts, too. This adaptation is the one that Calvin believes led to the rapid increase in hominid brain size over the past 2.5
million years, a development that produced such essential human traits as toolmaking, cooperation and planning. Changes in the circulation
pattern of ocean currents along Greenland drive the flips. These currents carry warm water, rich in excess salt,
from the tropics. When the salt reaches the north, it sinks and carries with it cooled surface water, which gets
transported back south. If the conveyor belt stopped, then Europe would have a cold and dry climate like
Canada, and the planet would settle into an ice age. Calvin makes a convincing argument for his thesis by tracing his ideas across the
globe and writing in what he calls an "E-seminar" style of travel briefs. Roughly half his accounts come from Africa, where he delves most deeply into our
evolutionary past. Each seminar is short, fact-filled and conversational. Nearly 40 pages of glossary and footnotes supplement the book .
Shut down of the ocean conveyor belt leads to natural disasters, destroys marine life, and only
causes further warming
Schiermeier 6 (Quirin, Since 1999, writer for Nature about science, degrees in geography, statistics and economics from the University of
Munich, “Climate change: A sea change,” 1/19/06, Nature Volume 439,
http://search.proquest.com.proxy.lib.umich.edu/docview/204525245/abstract?accountid=14667)
Wolfgang Cramer, an ecologist at PIK, predicts complex changes in the climate, with some effects exacerbating each other and some that cancel each
other out. For example, Cramer says, meteorological perturbations caused by a thermohaline shutdown could lead to a
dramatic increase in the frequency of major floods and storms in large parts of Europe even if overall temperatures do
not drop. “It’s not the mean, it’s the extremes that are most worrying,” he says. One aspect of the problem is that the thermohaline
cir- culation is not just a climatic affair. Its effect on ocean circulations means it influences the rates at which
nutrient- rich bottom water rises to the surface all around the world. A recent simulation suggests a shutdown might lead
North Atlantic plankton stocks to collapse to less than half their current biomass13. Globally, a decline of more
than 20% might be expected thanks to reduced upwelling of nutri- ent-rich deep water and gradual depletion of
upper-ocean nutrient concentrations. “Plankton builds the base of the marine food web. So a decline in global
plankton biomass and productivity can be expected to have consequences for fish, squid and whales as well,” says
Andreas Schmittner, a climate researcher at Oregon State University in Corvallis. “A weaker Atlantic overturning circulation could
result in a reduced fish supply to people living along the shore lines of the Pacific and Indian Oceans.” Other possible effects of a
shutdown predicted by models include warming in the tropics, or, rather surprisingly, over Alaska and Antarctica. Rainfall
patterns might change, too. A southern shift of the thermal equator — which has accompanied thermohaline
circulation shutdowns during ice ages — could lead to monsoon failures, and droughts in Asia and the Sahel
region, says Severinghaus, and these effects seem to be independent of sea ice. Such shifts could have severe consequences for poor
farmers in many parts of the world, consequences that may be considerably more dis- ruptive than colder winters in affluent northern
Europe, says Severinghaus. And, as Schlesinger points out, a weak- ening or stopping of the thermohaline circulation would
reduce the carbon dioxide uptake of the ocean, which would mean a positive feedback on global warming. The
oceans currently absorb about a third of the carbon dioxide released from fossil fuels, although the proportion is set to decrease as emissions climb.
Some 250 years after Captain Ellis first probed the Atlantic, its depths still hold secrets and threats. Even in a new age of constant monitoring and
improved modelling, it will be some time before the likelihood, and the probable effects, of a thermohaline circulation slowdown can be pre- dicted with
accuracy. The intricacies of a system that depends on delicate balances between fresh and salt water over vast ocean basins, on the details of atmospheric
circu- lation, wind-driven currents and the topography of deep sea floors will not yield answers quicKLy. “If you would like to learn how a planet operates
you would probably not choose the Earth,” remarks Schlesinger. We greenhouse dwellers, alas, do not have a choice.
Warming Causes Ice Age - CO2 Increase Inevitable
Increase in CO2 causes ice age
Brennan, 11 Philip V. Brennan, writer for Canada Free Press, “The Japanese Quake: Another Ice Age Precursor?”
http://www.canadafreepress.com/index.php/article/34349 Accessed 6/25/12
Studies of data collected from ocean bottom samples 200 miles off the coast of Ecuador by Nickolas ShacKLeton and associates at
provided CO2 readings for the past 130,000 years, a period covering the last
interglacial, the ice age that followed, and the current interglacial. “These data confirmed the rise of CO2 levels
that preceded the last ice age, and the point at which the process became inevitable
Britain’s Cambridge University
Alt Cause - Insolation
Anthropogenic GHG emissions are not the driving factor, insolation is key – we have
comparative evidence
Peltier and Vettoretti 11 (W.R., Ph. D. in Physics from the University of Toronto, Director of the Centre for Global Change Science, PI of the
Polar Climate Stability Network, Department of Physics at the University of Toronto, Dr. Guido Vettoretti, Research Associate in the Department of
Physics at the University of Toronto, “The impact of insolation, greenhouse gas forcing and ocean circulation changes on glacial inception,” 7/29/11,
http://hol.sagepub.com.proxy.lib.umich.edu/content/21/5/803.full.pdf+html)
We have focused on a set of experiments, using a coupled atmosphere–ocean model of moderate resolution, to
investigate the impact of both changes in GHG concentrations and insolation changes in order to better
understand the influence that these boundary condition changes have on high latitude perennial snow cover in
the model. The importance of internal decadal variability in the simulations was also addressed by examining the correlation between changes in the
AMOC and changes in surface temperature and snow cover at high northern latitudes in each of the experiments. The purpose of this study
was to address a number of long-standing issues regarding the relative role that GHG concentrations play as a
determining factor in the growth of ice sheets in the Arctic under reduced northern summertime insolation conditions. The early
anthropogenic hypothesis proposed by Ruddiman (2003) is predicated upon the notion that human
modifications of the environment in the early to late Holocene may have contributed to the arrest of what
would have otherwise been the onset of the next glacial cycle by increasing GHG concentrations in the
atmosphere and thus warming the planet. The excellent records of GHG concentrations from Antarctica, along with
detailed calculations of insolation throughout the second half of the Quaternary allow us to draw analogues
between the modern interglacial and the set of interglacials that have occurred in the past 800 000 years. MIS 11
and the modern interglacial, often used as analogues for one another, have a number of significant differences in orbital signature that make
comparisons difficult. In particular, eccentricity-precession and obliquity are out of phase just after Termination five (MIS 11) and are in phase just after
the last glacial termination that leads into the Holocene. We find that this basis of comparison is rather inconclusive as a
means of addressing arguments for or against the early anthropogenic hypothesis. Instead we focus on a series
of modelling studies with strong and weak insolation forcing and low and high GHG concentrations and
including the internal variability characteristic of a coupled model. The evolution of the AMOC is correlated with global and
regional temperatures in the coupled model that we employ. Equilibrating the climate requires hundreds of simulation years to obtain a stable climate,
that we have shown is characterized by large fluctuations in regional high latitude temperatures which correlate well with the AMOC maximum. The
statistically equilibrated climate is also subject to a number of anomalies with respect to the modern observed climate. In particular, there are high
latitude cold biases and anomalously high amounts of snow coverage in Northern Hemisphere summer. These biases are shown to manifest themselves
in each of the glacial inception experiments presented in this study. In particular we find too much snow accumulation in the regions of northwestern
North America and eastern Siberia. While we have not directly addressed the cause for this excessive snow accumulation, the errors in the sea-ice
simulated in the CCSM3 (Holland et al., 2006) are a possible cause for this anomalous permanent snow cover. The land surface snow cover
parameterization in the model also has a number of deficiencies in the physical simulation of permanent snow cover that includes limits on snow
accumulation. The set of six glacial inception simulations demonstrate that the impact of the 116 ka BP insolation
regime is the strongest factor in determining the extent of perennial snow cover. The level of GHG
concentrations (CO2 between 240 and 260 ppmv) plays a secondary role in determining the extent of snow
cover in both the pre-industrial era and at 116 ka BP. The changes in snowfall rate in the Arctic were shown to be highly
correlated with surface temperature in these regions. The significant changes in snowfall rate were influenced
to first order by insolation changes rather than the atmospheric GHG concentration. The decadal variability in Arctic
summer surface temperature and snowfall appear to be correlated with AMOC strength but a regression analysis between these variables does not
provide strong evidence for a relationship between AMOC strength and perennial snow cover changes. The AMOC strength appears relatively constant
(to within 2–3 Sv) between the 116 ka BP experiments and the pre-industrial experiments. We are nevertheless unable to rule out the possibility that
changes in internal variability of the climate system may play a significant role in the glacial inception process as longer and more detailed studies may
be required (e.g. the melt back of Greenland during the end of the Eemian, when surface temperatures were 1–2°C warmer than present (Kaspar et al.,
2005)). The magnitude of the impact that early anthropogenic activity had on climate will require further analyses. This study, while not directly
addressing the validity of the early anthropogenic hypothesis, investigated
the component of the hypothesis that suggested that
early anthropogenic carbon emissions would have resulted in the suppression of the start of the next ice age
well before the onset of the industrial revolution. The results of our analysis, which illustrate the impact of
reductions in GHGs during the pre-industrial period (CO2 from 240 to 280 ppmv), do not display any significant glacial
inception in the Canadian Arctic Archipelago. This is contrary to the idea that changes in Holocene GHG
concentrations of the magnitude suggested by Ruddiman (2007) would have been sufficient to eliminate the
onset of perennial snow cover that would otherwise have occurred in the Holocene in the absence of
anthropogenic forcing. Our analyses also suggest that insolation forcing is by far the most significant driver of
the glacial inception process with GHG concentration playing a secondary role. Using an additional set of two simulations
of the future (10 ka AP and 51 ka AP), we propose that the closest modern analogue for conditions favourable to glacial inception is less than 10 000
years into the future when Earth’s obliquity achieves a local minimum and insolation is reduced in Northern Hemisphere late summer and fall at high
latitudes. Our simulations, using mean interglacial GHG levels, indicate that the current interglacial will last for at most approximately 20 000 years. It
will be interesting in future work to investigate the level of GHG concentrations that would have to be reached following injection of the CO2 spike that
humankind is currently adding to the system in order that a further glacial cycle may occur.
Insolation is key to prevent an ice age, anthropogenic GHG emissions are secondary
Peltier and Vettoretti 11 (W.R., Ph. D. in Physics from the University of Toronto, Director of the Centre for Global Change Science, PI of the
Polar Climate Stability Network, Department of Physics at the University of Toronto, Dr. Guido Vettoretti, Research Associate in the Department of
Physics at the University of Toronto, “The impact of insolation, greenhouse gas forcing and ocean circulation changes on glacial inception,” 7/29/11,
http://hol.sagepub.com.proxy.lib.umich.edu/content/21/5/803.full.pdf+html)
The variations in GHG concentration and insolation in each of the simulations we have discussed provide a
means whereby the sensitivity of this model to initiating perennial snow cover at high latitudes may be
assessed. The response of the amplitude of the AMOC maximum to these changes in boundary conditions also provides an additional means of
assessing the impact of model internal variability on the glacial inception process. What is particularly important in the present study
is to separate the relative importance of each factor in contributing to the inception process . In Figure 5 we illustrate
the relative role that each of these factors plays in the set of sensitivity experiments by displaying the variations of global average surface temperature,
Arctic summer land surface temperature, Arctic snowfall over land, and the response of the amplitude of the AMOC over the last 200 years of each
statistically equilibrated simulation. Each of the annually averaged 200 yr time series are displayed with a 20 yr running mean to better highlight the
interannual and decadal variations occurring in each of the experiments. On an annually and globally averaged basis, changes in insolation would have a
negligible effect if it were not for the dominance of land masses in the Northern Hemisphere (Figure 5(a)). For example, at 116 ka BP the reduced
summer insolation at mid to high northern latitudes is compensated by increased winter insolation in the Southern Hemisphere tropics and midlatitudes. In fact, the changes in global average temperature in these experiments are dominated by reductions in GHG concentrations. The temperature
ranges between 12°C and 13°C from the low GHG experiments to the high GHG experiments, respectively, with insolation playing a rather minor role. If
we instead focus on the annual and decadal variability of the high latitude Arctic summer land surface temperatures (Figure 5(b)), we see that the
changes in temperature are completely determined by the insolation regime characteristic of the experiment. The changes in land surface temperature in
the GHG experiments with the 116 ka BP insolation regime are up to 3°C colder than in the pre-industrial experiments with varying GHG concentrations.
The insolation changes bring the climate from a zero melting point regime to well below freezing. This has significant implications for the role of GHG
concentrations in creating conditions that are favourable to glacial inception during the latter part of the Holocene . If the high latitude model
sensitivity to GHG concentrations in the model is correct, then variations in CO2 concentrations between 240
and 280 ppmv are expected to have approximately 30% of the forcing (~1°C) relative to insolation on creating
conditions that are favourable for high latitude perennial snow accumulation. Since the snow cover parameterization in the
land surface model has some significant glacialogical implications in the formation of perennial ice sheets and glaciers, we instead analyse the flux of
solid precipitation to the land surface in each of the experiments (Figure 5(c)). The snowfall rate is much more variable than that of the surface
temperature over high latitude land areas. The 20 yr running mean provides a more robust indication of the decadal variations in snowfall rate in these
high latitude areas. The most significant change in each of the experiments is the increase in the rate of snowfall with
decreases in summer insolation characteristic of 116 ka BP. The impact of reductions in GHG concentrations
appear to play a secondary role in the equilibrated perennial snow cover simulations. In particular, no significant
change is seen in the snowfall rate in the 116 ka BP insolation experiments with variations in GHG
concentration. In the preindustrial insolation regime, the GHG concentration variations appear to have some influence on snowfall rate in the latter
100 yr segment of the 200 years of equilibrated climate. Changes in AMOC strength may be related to changes in the phase of the Arctic Oscillation
(Thompson and Wallace, 1998) which governs much of the interannual variability in the Arctic through ocean–atmosphere coupling (Lohmann et al.,
2009). Recently, in a long coupled model simulation of the pre-industrial climate using CCSM3, the Atlantic Multidecadal Oscillation (AMO) that is
associated with AMOC strength was found to exhibit a 60 yr cycle in variability (d’Orgeville and Peltier, 2009). However, changes in sea ice were shown
not to be sufficient to explain changes in the AMOC variability. The AMOC amplitude (Figure 5(d)) is characterized by interannual and decadal
variability varying between 17 and 20 Sv in all of the simulations. It is possible that these changes in AMOC strength impact the changes observed in the
globally averaged and regionally averaged surface temperatures (Figure 5(a) and (b)). This correlation between high latitude surface temperature and
AMOC that was clearly visible in Figure 2 is not so apparent in each of the perennial snow cover experiments. Thus we have employed a regression
analysis in what is to follow. A regression analysis between the 20 yr running mean Arctic summer surface temperature, Arctic summer snowfall rate and
AMOC strength are displayed in Figure 6. The regression between surface temperature and snowfall rate indicates only a
slight sensitivity of the model to the changes in the GHG concentration in both the pre-industrial experiments
and the 116 ka BP experiments. The R 2 correlation coefficient indicates that there is a higher degree of
correlation between surface temperature and snowfall in the pre-industrial CO2 sensitivity experiments. The
significant changes in snowfall rate occur in the 116 ka BP experiments as described in Figure 5. In each pre-industrial experiment, the correlation
between surface temperature and AMOC strength displays roughly the same degree of sensitivity to CO2 as in Figure 6(a). While the Arctic surface
temperature changes in the set of six experiments, the AMOC appears relatively insensitive to both insolation forcing and CO2 forcing. In a previous
study, Khodri et al. (2001) also find that the AMOC maximum does not change significantly between their 115 ka BP simulation and their control
simulation. In the regression analysis between snowfall and AMOC strength the correlations are evident in the
pre-industrial experiments but completely break down in the 116 ka BP experiments. In general, the regression analysis
indicates that the AMOC strength appears relatively insensitive (2–3 Sv) to changes in both CO2 and insolation forcing. Thus, insolation and CO2 forcing
appear to have more of an impact on the snowfall rate at high latitudes rather than do changes in internal ocean variability.
Alt Cause - Winds
Wind shifts are the primary cause
Lamont-Doherty Earth Observatory 10 - Columbia University Earth Institute ("Study Adds New CLue to How last Ice Age Ended",
September 8, 2010, http://www.ldeo.columbia.edu/news-events/study-adds-new-clue-how-last-ice-age-ended)//KL
The overall trigger for the end of the last ice age came as Earth’s orientation toward the sun shifted, about 20,000
years ago, melting the northern hemisphere’s large ice sheets. As fresh melt water flooded the North Atlantic Ocean, the Gulf Stream
weakened, driving the north back into the ice age. During this time, temperatures in Greenland dropped by about 15 degrees C. For years, scientists have
tried to explain how the so-called Younger Dryas cooling fit with the simultaneous warming of Antarctica that eventually spread across the globe. The
Nature paper discusses the two dominant explanations without taking sides. In one, the weakening of the Gulf Stream reconfigures
the planet’s wind belts, pushing warm air and seawater south, and pulling carbon dioxide from the deep ocean
into the air, causing further warming. In the other, the weakened Gulf Stream triggers a global change in ocean
currents, allowing warm water to pool in the south, heating up the climate. Bob Anderson, a geochemist at Lamont-Doherty
who argues the winds played the dominant role, says the Nature paper adds another piece to the puzzle. “This is one of the most pressing
problems in paleoclimatology because it tells us about the fundamental processes linking climate changes in the northern and southern hemispheres,” he
said. “Understanding how regional changes influence global climate will allow scientists to more accurately predict regional variations in rain and
snowfall.”
No Impact - Gradual
The ice age will come slow – this guarantees adaptability
Custodio, 11 11/2/11, “Can Humans Survive another Ice Age?” http://leecustodio.hubpages.com/hub/Can-Humans-Survive-another-Ice-Age
Accessed 6/25/12
On today’s modern society wherein information is at our fingertips and technologies are being developed every
day, the chances of human survival towards another ice age is greater than before with the utilization of
technological advances that we have now. Information dissemination regarding the matter is easier with the use of
the internet, education through other mass media like television and print and new technological inventions to prepare
humans for the coming of the ice. Infrastructures such as innovative and mammoth engineering could be
developed in such a way that it can repel much of the cold. Infrastructure can also be modified to make massive
collective farm for growing food indoors possible; same goes with the idea of raising cattle and poultry indoors.
Handy gadgets and tools could also make all the difference. Improve communication via mobile phones and PDAs, innovative means of
transportation that can make use of ice or the air’s humidity as fuel, and as source of energy. Farfetched ideas can
become reality when necessity demands it. Survival is all about preparation. Preparation and reparation are currently being done through organizations
that focus in helping the environment, various government programs and media advocacies. Today we are already experiencing the effects of the changes
in weather. Probably not all will survive, but an ice age will not be the doom of human beings. Gone are the ideas that we
would go back to the “basics” we can use and improve the things that we have now, since we do have the time, to prepare
for an ice age. Ice age will not come in a blink of an eye, or in a wave of a wand, it will come relatively fast—decades, but that given period,
the indomitable spirit and knowledge of the people can outsmart whatever Mother Nature would bring.
No Impact - Tech solves
Tech enables adaptability to the ice age
England, 11 Christopher England, “Will we survive the coming Ice Age?” http://www.christopherengland.com/2011/06/will-we-survive-comingice-age.html Accessed 6/25/12
So, as we are now faced with the need to change and adapt in order to survive the coming mini-Ice Age as
temperatures continue to drop throughout Europe (and the North Americas), will we take the Inuit route or the Viking one? I think
that with far more technology and understanding surrounding us than was available in the 1300s, we will be
able to deal with it technically. But what about politically? The only real problem we have is the stranglehold on our industries that
the left-wing global warming religion and lobby currently has. By putting their pointless carbon taxes onto everything they can, and funding silly green
ideas instead (like wind-farms that aren't able to function to generate electricity when they are iced-up), they are not actually allowing us to start
preparing for the coming era of long frozen winters and soggy summers, which will be with us for at least the next 70 years or so. Indeed, fuel prices are
already rocketing and putting thousands into fuel poverty because of their carbon taxes. Will the long extended periods of freezing kill off the elderly and
poor? It certainly killed thousands back in the previous mini-Ice Age that covered Britain. I suspect that because of our unpreparedness it will take
the staking up of bodies in local mortuaries before Governments wake-up and react to the real needs of society
to deal with climate change. Unfortunately, everything is skewed the wrong way because of the global warming religion. Generally speaking
though, we will survive. We lived through periods of iced-over rivers and unworkable farmland before. This time
we are far more technologically advanced, and assuming sea-ice doesn't cause too much disruption, we are far
more geared towards importing goods from warmer climes, or genetically modifying food and growing it
'inside' rather than leaving it out in the snow and ice. It'll be fine; most of us will survive, so don't panic!
No extinction -- technology solves
Croatian Times 10 - quoting physicist Vladimir Paar from Zagreb University ("Croat Scientist Warns Ice Age Could Start in Five Years"
October 2, 2010, http://www.croatiantimes.com/news/General_News/2010-0210/8836/Croat_scientist_warns_ice_age_could_start_in_five_years)//KL
The Zagreb based scientist says it will still be possible for humans to survive in the ice age, but the spending on energy
will be enormous. "Food production also might be a problem. It would need to be produced in greenhouses with a lot of
energy spent to heat it", commented the professor, who remains optimistic despite his predictions. He said: "The nuclear energy we know
today will not last longer than 100 years as we simply do not have enough uranium in the world to match the
needs in an ice age. But I'm still optimistic. There is the process of nuclear fusion happening on the Sun. The
fuel for that process is hydrogen and such a power plant is already worked on in France as a consortium involving firms
from Marseille and the European Union, the US, Russia, China, Japan and South Korea. The head of the project is a Japanese expert, and former
Japanese ambassador in Croatia", Vladimir Paar revealed. He said the building of the new technology power plant will take at least another 10 years. "In
40 years we'll know how it functions. That would be a solution that could last for thousands of years. We have a
lot of hydrogen and the method is an ecological one", the professor concluded.
No Impact - Self Correcting
Ice depression means warm waters will control the impact -- the bigger the ice age the smaller
the impact
Grigg 11 - Campbell River Courier staff writer quoting a climate researcher (Dr. Larry Edwards) from the University of Minnesota (Ray, "Ice Ages,
Climate CHange, and Carbon Dioxide", April 29, 2011, http://www.canada.com/Ages+Climate+Change+Carbon+Dioxide/4694593/story.html)/KL
The new explanation is that ice ages are partly responsible for their own demise. As they get larger and heavier,
they depress the planet's crust, thus lowering their elevation and causing melt from higher temperatures.
Additionally, the foundations of the ice sheets may sink below sea level, allowing warm ocean water to undermine
and destabilize them. When Earth's axis shifts enough to cause additional summer warming, then the ice age ends.
Emissions Don't Solve - Conveyor Belt
Warming can’t solve ice age – the Ocean Conveyer Belt is strengthening and the rate isn’t fast
enough
Chameides 10 (Bill, Dean of the Nicholas School of the Environment and Earth Sciences at Duke University, member of the National Academy of
Sciences, Ph. D. from Yale University, “Good News: No Sign of Slowing Ocean Conveyor Belt,” 3/29/10,
http://www.scientificamerican.com/article.cfm?id=good-news-no-sign-of-slowing-ocean)
Among the concerns about global warming is the specter of rapid climate change -- the possibility that slowly warming temperatures could suddenly
trigger a swift and major shift in the climate system with catastrophic consequences. In the 1990s some climate scientists warned of
the possibility of one such scenario: an ice age caused by the shutdown of the so-called ocean conveyor belt.
Ocean Conveyor Belt and Climate One of the critical jobs of the climate system is to move heat from the tropics, where
much of the energy from the Sun is deposited, to the cool polar regions. The atmosphere does much of this redistribution, but
the ocean is also a key player. As noted in an earlier post, "without the oceanic and atmospheric mechanism, the temperature difference
between the poles and the equator would be an astounding 200 degrees Fahrenheit rather than the 55-degree difference that exists today." The
ocean's heat redistribution in the Northern Hemisphere is largely accomplished by the so-called ocean
conveyor belt (in more technically inclined company we refer to this as the Atlantic meridional overturning circulation or
AMOC or simply MOC). It works like this: Warm topical waters in the Atlantic Ocean flow northward along the Gulf Stream. Along the way the
waters cool (providing a source of heat to northern climes) and evaporate (making the remaining waters of the Gulf Stream saltier). As water becomes
cooler and saltier, it gets denser. Near Greenland and the Norwegian and Labrador seas, the dense water, now heavier than that below, sinks. The cold,
sinking water eventually closes the conveyor belt by flowing southward and resurfacing. Sudden Ice Age Onset? Could global warming change all that?
Some have speculated yes, arguing that melting glaciers could dilute that salty water in the Gulf Stream's
northern reaches, preventing it from getting dense enough to sink. (See here and here.) Without sinking in the north,
the waters moving northward in the Gulf Stream have nowhere to go and so the flow of the Gulf Stream would
have to eventually stop. And without the Gulf Stream and its transport of heat northward, the Northern
Hemisphere could get quite cold -- perhaps cold enough to bring ice-age conditions back to our latitudes. Global
warming causing an ice age? It sounds rather oxymoronic and perhaps as far-fetched a prediction as the disaster scenario depicted in 2004's blockbuster
The Day After Tomorrow. But there is at least an ounce of reality to the scenario. A Refresher: Ice Age in Not Too Distant Past Set Off by an Influx of
Fresh Water There is some evidence to suggest that such sudden deep freezes may have happened in the past, for example during the so-called Younger
Dryas. Scientists believe that about 12,000 years ago, as the last ice age was on the wane, a huge amount of
meltwater released from a colossal glacial lake in the middle of North America was dumped into the northern
Atlantic via the St. Lawrence Seaway. This sudden injection of fresh water, it is theorized, shut down the ocean
conveyor belt and thrust the Northern Hemisphere back into ice-age conditions over a couple of thousand
years. But that was then and this is now. Could the present-day melting of glaciers in Greenland do the same thing? Well,
observations indicate that the waters of the Labrador and Norwegian Seas are becoming less salty. But the rate at which fresh water is
being added is considerably slower that that huge injection way back in the Younger-Dryas. And model
calculations suggest that the current change is not rapid enough to cause an actual shutdown of the ocean
conveyor belt. Support for this contention has now been provided by a new paper in Geophysical Research
Letters by Josh Willis of the California Institute of Technology's Jet Propulsion Laboratory. Using a
combination of satellite observations of sea-surface heights and measurements of ocean temperature, salinity,
and currents, Willis found "no significant trend in overturning strength between 2002 and 2009." And, if
anything, the strength of the ocean conveyor has actually increased since 1993. Willis concludes that "substantial slowing of
the AMOC did not occur during the past 7 years and is unlikely to have occurred in the past 2 decades." So you can probably cross "sudden ice age" off
the top of your worry-list for the immediate future anyway. And feel free to chucKLe at the sight of Dennis Quaid trying to outrun the advancing ice in
The Day After Tomorrow.
Warming o/w - Timeframe
No risk of an impact – the timeframe for ice age is too far in the future, it's try or die for the aff
Black 12 – Environment correspondent for BBC News quoting Professor Luke Skinner – Climate Science in Department of Earth Sciences at
Cambridge University, Royal Society University Research Fellow, (Richard, “Carbon emissions 'will defer Ice Age',” 1/9/12, BBC News – Science and
Environment, http://www.bbc.co.uk/news/science-environment-16439807)
Human emissions of carbon dioxide will defer the next Ice Age, say scientists. The last Ice Age ended about 11,500 years ago,
and when the next one should begin has not been entirely clear. Researchers used data on the Earth's orbit and other things to find the historical warm
interglacial period that looks most like the current one. In the journal Nature Geoscience, they write that the next Ice Age would begin within 1,500 years
- but emissions have been so high that it will not. Continue reading the main story “ Start Quote I don't think it's realistic to think that
we'll see the next glaciation on the [natural] timescale” "At current levels of CO2, even if emissions stopped
now we'd probably have a long interglacial duration determined by whatever long-term processes could kick in
and bring [atmospheric] CO2 down," said Luke Skinner from Cambridge University. Dr Skinner's group - which also
included scientists from University College London, the University of Florida and Norway's Bergen University - calculates that the atmospheric
concentration of CO2 would have to fall below about 240 parts per million (ppm) before the glaciation could
begin. The current level is around 390ppm. Other research groups have shown that even if emissions were shut off instantly,
concentrations would remain elevated for at least 1,000 years, with enough heat stored in the oceans potentially to cause significant melting of polar ice
and sea level rise. Orbital wobbles The root causes of the transitions from Ice Age to interglacial and back again are the
subtle variations in the Earth's orbit known as the Milankovitch cycles, after the Serbian scientist Milutin Milankovic who
described the effect nearly 100 years ago. Glaciation and its reverse are related to cycles discovered by Milutin Milankovic The variations include the
eccentricity of the Earth's orbit around the Sun, the degree to which its axis is inclined, and the slow rotation of its axis. These all take place on timescales
of tens of thousands of years. The precise way in which they change the climate of the Earth from warm interglacial to cold Ice Age and back every
100,000 years or so is not known. On their own, they are not enough to cause the global temperature difference of about 10C between Ice Age and
interglacial. The initial small changes are amplified by various factors including the release of carbon dioxide into the atmosphere as warming begins,
and absorption of the gas by the oceans as the ice re-forms. It is also clear that each transition is different from previous ones, because the precise
combination of orbital factors does not repeat exactly - though very similar conditions come around every 400,000 years. The differences from one cycle
to the next are thought to be the reason why interglacial periods are not all the same length. Using analysis of orbital data as well as samples from rock
cores drilled in the ocean floor, Dr Skinner's team identified an episode called Marine Isotope Stage 19c (or MIS19c), dating from about 780,000 years
ago, as the one most closely resembling the present. The transition to the Ice Age was signalled, they believe, by a period when cooling and warming
seesawed between the northern and southern hemispheres, triggered by disruptions to the global circulation of ocean currents. If the analogy to
MIS19c holds up, this transition ought to begin within 1,500 years, the researchers say, if CO2 concentrations
were at "natural" levels. As things stand, they believe, it will not. Loving CO2 The broad conclusions of the team were endorsed by Lawrence
Mysak, emeritus professor of atmospheric and oceanic sciences at McGill University in Montreal, Canada, who has also investigated the transitions
between Ice Ages and warm interglacials. "The key thing is they're looking about 800,000 years back, and that's twice the
400,000-year cycle, so they're looking at the right period in terms of what could happen in the absence of
anthropogenic forcing," he told BBC News. He suggested that the value of 240ppm CO2 needed to trigger the next
glaciation might however be too low - other studies suggested the value could be 20 or even 30ppm higher. "But
in any case, the problem is how do we get down to 240, 250, or whatever it is? Absorption by the oceans takes
thousands or tens of thousands of years - so I don't think it's realistic to think that we'll see the next glaciation
on the [natural] timescale," Prof Mysak explained. Groups opposed to limiting greenhouse gas emissions are
already citing the study as a reason for embracing humankind's CO2 emissions. The UK lobby group the Global Warming
Policy Foundation, for example, has flagged up a 1999 essay by astronomers Sir Fred Hoyle and Chandra
Wickramasinghe, who argued that: "The renewal of ice-age conditions would render a large fraction of the world's major food-growing areas
inoperable, and so would inevitably lead to the extinction of most of the present human population. "We must look to a sustained greenhouse effect to
maintain the present advantageous world climate. This implies the ability to inject effective greenhouse gases into the atmosphere, the opposite of what
environmentalists are erroneously advocating." Luke Skinner said his group had anticipated this kind of reception. "It's an
interesting philosophical discussion - 'would we better off in a warm [interglacial-type] world rather than a glaciation?' and probably we would," he said.
"But it's missing the point, because where we're going is not maintaining our currently warm climate but
heating it much further, and adding CO2 to a warm climate is very different from adding it to a cold climate.
"The rate of change with CO2 is basically unprecedented, and there are huge consequences if we can't cope with
that."
Next ice age is at least 50,000 ways away -- no need for urgent management
Brock 11 - Staff writer for the Watertown Daily Times (Chris, "Taking long, long view on climate change", Watertown Daily Times, March 19,
http://www.watertowndailytimes.com/article/20110319/CURR04/303199998/?loc=interstitialskip)//KL
Mr. Stager writes that most climate models predict another ice age at the year 50,000. Humans,
he said, have stopped
that "in its tracks" because of carbon dioxide emissions. The next ice age will arrive around the year 130,000.
But not if "we burn through all our remaining coal reserves during the next century or so," Mr. Stager writes. If we do
that, he said, the next ice age won't hit for the next half million years.
No Link - CO2 not key
Doesn’t link to the aff – water is the key greenhouse gas, the aff only reduces CO2
Hoyle and Wickramashinge 99 (Fred – Institute of Astronomy at Cambridge, Chandra – Director of the Buckingham Centre for
Astrobiology, School of Mathematics at Cardiff University, “On the cause of ice-ages”, 1999, CCNet)
1. The Greenhouse Effect The greenhouse effect raises the Earth's temperature by about 40oC above what it would otherwise have been. Without
the
greenhouse effect the Earth would be locked into a permanent ice-age. This fact gives the lie to those renegade scientists, who
in their anxiety to get their hands into the public purse, are seeking to persuade the public that the greenhouse effect is a bad thing greatly to be feared.
The reverse is true. The greenhouse effect is an exceedingly good thing, without which those of us who happen to live
in Britain would be buried under several hundreds of metres of ice. Water vapour and carbon dioxide are the
main greenhouse gases. Carbon dioxide produces essentially the whole of its effect through absorption at
infrared wavelengths from about 13.5mm to 17.5mm. Because the blocking by carbon dioxide over this interval is
large, the band having steeply-falling wings, additions of carbon dioxide have only a second-order influence on
the greenhouse effect and are inconsequential compared to the major factors which control the Earth's climate.
The blocking effect of water vapour rises all the way from 17.5mm to almost 100mm. The wavelength 13.5mm is
important in two respects. In the energy distribution of radiation emitted at ground and sea-level it marks the halfway point, one-half of the energy being
at wavelengths shorter than 13.5mm and one-half at wavelengths longer. It also marks a division in the effectiveness of the blocking of greenhouse gases.
Shortward of 13.5mm the blocking is comparatively weak, longward of 13.5mm it is strong, excepting for a
partial window from 17.5mm to about 20mm. Shortward of 13.5mm there is a broad weak absorption from water vapour with its
minimum in the region of 10mm, together with narrow bands from 03 and CH4. Of these, some current fuss is being made about CH4. But blocking by
methane is somewhat shortward of 8mm, which is so far out on the short wavelength tail of the Earth's reradiated spectrum as also to be of no great
consequence. Thus the Planck maximum for a reradiated spectrum of, say, an effective temperature 290K is at 17.6mm with respect to energy, and at
12.7mm with respect to maximum photon emission. Thus methane makes its contribution in a region of the reradiated spectrum where there is only 10
percent of the energy, for which reason fluctuations in atmospheric methane can produce only minor effects, like those produced by fluctuations of CO2.
The gas that can produce major effects, and towards which one must therefore look for an understanding of
large shifts of the Earth's climate, is water vapour.
No Link - Middle ground
Partial is the middle ground -- we can cut emissions while avoiding ice age
Brock 11 - Staff writer for the Watertown Daily Times (Chris, "Taking long, long view on climate change", Watertown Daily Times, March 19,
http://www.watertowndailytimes.com/article/20110319/CURR04/303199998/?loc=interstitialskip)//KL
"Deep Future" delves into the "ethical dilemma" of today's use of fossil fuels and the effect their emissions will have on the next millennium while also
saying it could "save much later generations from having to endure inevitable ice ages." Mr. Stager said there could be a "middle route" in
dealing with fossil fuels if we follow a "moderate-emissions path." "Then we'll probably be leaving most of our
coal reserves where they lie and running our future civilizations on other energy sources ," he writes in "Deep Future."
"Environmental damage during the next several centuries will be held to a minimum, some societies might benefit from a partial and temporary opening
of the Arctic Ocean, and the next ice age of 50,000 AD will be held at bay." Future generations also could benefit from wise
management of our natural resources, Mr. Stager writes, "Not necessarily as fuel but rather as a simple, cost-effective
tool for climate control." 'RAISING THE BIGGER PICTURE' Mr. Stager said it may seem like "science fiction" to some to take such long views
of Earth's climate. "What I hope to do, by raising the bigger picture, is saying there's way more to this story than just the short-term global warming we're
all talking about," Mr. Stager said. "I think we need to move on to another level and say what's the long-term balance? Some
people are going to benefit and some are going to lose, and some species, too." Mr. Stager said records show a pattern of less ice coverage on Adirondack
lakes today compared to the past several decades. He no longer takes his students out onto some of those lakes in the winter because of unreliable ice
thickness — a small example of how humans must adapt to climate change. "We're going to have to adapt, but it doesn't mean that
we should also give up trying to reduce the impact because what we do now is going to determine the climatic
future for tens of thousands of years," he said. "Why not make it so we only have to adapt a little, instead of a lot?"
Mr. Stager, who has a Ph.D. in biology and geology from Duke University, said he's "walking a fine line" by tacKLing such a polarizing topic. "I try to walk
that middle ground with what I'm pretty sure are pretty good solid facts, take a long-term view and let that raise a whole new crop of important questions
that haven't been addressed yet," he said. "I leave it to people to move the conversation along and be a little bit more productive."
AT: Conveyor Belt Theory
Conveyor Belt theory is wrong – not enough freshwater to cause an ice age
Schiermeier 6 (Quirin, Since 1999, writer for Nature about science, degrees in geography, statistics and economics from the University of
Munich, “Climate change: A sea change,” 1/19/06, Nature Volume 439,
http://search.proquest.com.proxy.lib.umich.edu/docview/204525245/abstract?accountid=14667)
The result came as a surprise to those in the field. Few scien- tists had thought that such dramatic slowing of the thermo- haline circulation could happen
so soon. Models suggest6 that the increase in fresh water needed for a conveyor shut- down would not be
expected without a global warming of 4–5 RC; warming in the twentieth century is currently put at 0.6 RC (ref.
3). The most complex computer models of the cli- mate and oceans, the sort used to make climate predictions
for the Intergovernmental Panel on Climate Change (IPCC), suggest that the flow might be expected to slow by
an aver- age of 25% by the end of the twenty-first century, but not to shut down completely3. Running complex
models long enough to simulate some sorts of change, however, uses an unfeasible amount of com- puting power. So for some purposes ‘intermediate’
models can capture things better. Stefan Rahmstorf, an oceanogra- pher at the Potsdam Institute for Climate Impact Research (PIK) in Germany recently
compared the circulation’s response to an influx of fresh water in 11 simpler models; all showed a threshold, called the bifurcation point, beyond which
the thermohaline circulation cannot be sustained7. The size of the threshold suggests that the possibility of shutdown is real,
but not immediate. Rahmstorf says, “It is very unlikely that it will become really critical for the thermohaline
circulation within the next 100 years.” This is not to say that freshwater flows are not increasing; they are. The annual runoff of the six
mightiest rivers draining into the Arctic Ocean, including Russia’s Ob, Lena and Yenisey, is now 128 cubic kilometres greater than it was when routine
measurements began 70 years ago8, an increase of about 7%. In addition, rising temperatures are making sea ice melt more rapidly. Perhaps most
important, the huge Greenland ice sheet is showing worrying signs of disintegration; it is currently thought to be shrinking by 50 cubic kilometres per
year9. Ruth Curry, an oceanographer at Woods Hole Oceano- graphic Institution in Massachusetts, has investigated how much of this extra fresh water
lingers in the parts of the Greenland and Labrador seas that are critical for the func- tioning of the thermohaline circulation. Her recent analy- sis10 of
1950 to 2005 salinity data suggests that 4,000 cubic kilometres — eight times the annual outflow of the Missis- sippi river — of fresh water have
accumulated in the upper ocean layers since the 1960s. “The extra freshwater input is beginning to affect density,” she says. But
the amount of fresh water needed to shut down the thermohaline circula- tion in Rahmstorf ’s comparisons is
an order of magnitude greater than the flux reported by Curry, and she agrees that the circulation will not be unduly
affected this century. Peter Wadhams, an oceanographer at the University of Cambridge, UK, last year reported a substantial weakening of
convection ‘chimneys’ down which surface water flows in the Greenland sea, but it is unknown how much of the observed effect is due to natural
variability. This is all hard to reconcile with Bryden’s findings, which suggest that a strong slowdown is already under way. “Some- thing strange is going
on here,” says Michael Schlesinger, a climate modeller at the University of Illinois at Urbana-Champaign who views the possibility of a thermohaline
circulation shutdown as more likely and more worrying than many of his peers. “If Bry- den’s findings are real it means that the circulation is much more
sensitive to fresh water than any model has ever predicted.” It is not just that the results are unexpected — they also seem hard to reconcile with other
data. If the cir- culation were slowing down as Bryden suggests, one might expect that Europe would already be
getting colder. The North Atlantic transports around a petawatt of heat — equivalent to the thermal output of about 500,000 large power stations
— towards Europe. Interrupting that flow should have a cooling effect on the climate, but no such change has been
seen.
AT: Conveyor Belt – Ice Mass
No ocean conveyor belt theory – low sea ice mass
Schiermeier 6 (Quirin, Since 1999, writer for Nature about science, degrees in geography, statistics and economics from the University of
Munich, “Climate change: A sea change,” 1/19/06, Nature Volume 439,
http://search.proquest.com.proxy.lib.umich.edu/docview/204525245/abstract?accountid=14667)
It may be that the system has a previously unexpected level of natural variation. Or it could be that Bryden recorded noise, rather than a signal — did a
set of readings, through coincidence, the presence of ocean eddies and other nat- ural disturbances, make it seem that the circulation was slowing when it
wasn’t? A statistical artefact cannot be excluded. “The results are based, after all, on just five snap- shots of an extremely noisy and under-sampled
system,” says Carl Wunsch, a physical oceanographer at the Massa- chusetts Institute of Technology, who harbours long-stand- ing doubts about the
significance of the thermohaline circulation and its possible shutdown. “The story is appeal- ing, but it is a very extreme interpretation of the data. It’s
like measuring temperatures in Hamburg on five random days and then concluding that the climate is getting warmer or colder.” In response to his
critics, Bryden points to data on the density of the ocean at various depths gathered at the same time as the flow readings, which provide independent
support for the idea that the circulation is slowing. But although other scientists are less harsh than Wunsch, many remain cautious. “Bryden’s results are
extraordinary,” says Schmidt, “but this is exactly why they also require extraor- dinary evidence.” If Bryden’s results are correct, there is another
explana- tion of the lack of cooling in Europe: that a slowdown of the thermohaline circulation will not have the
dire effects that have been suggested. It may be that, in today’s climate, the role of the thermohaline circulation in
warming Europe has been overestimated. A paper published in 2002 sug- gested that the westerlies, the dominant winds in mid-latitudes that blow from west to east play a much larger role than was long thought11. But much of the heat transported in the atmosphere ultimately comes
from the ocean. “It is true that the atmosphere does the heavy lifting,” says Jeff Severinghaus, an oceanographer at the Scripps Institution of
Oceanography in La Jolla, California, who was once a student of Broecker’s. “But the ocean exerts the control, just like the driver of a car.” Evidence
for the huge effects of past thermohaline shut- downs is near indisputable. The best case is that of a 1,300- year
cold period that occurred around 12,000 years ago, known as the Younger Dryas. The carbon isotope ratios in fossilized
plankton from the period suggest that the ther- mohaline circulation was much slower than it is today (slow circulation allows light carbon isotopes to
build up near the ocean’s surface). This slowdown coincided with a vast surge of fresh water into the North Atlantic. The melting of the ice-caps as the ice
age ended created a vast reservoir of fresh water known as Lake Agassiz. It was far larger than any of today’s Great Lakes, over parts of Minnesota,
Dakota and Manitoba — Lake Agassiz. To the east, the lake was bordered by a tongue of the Laurentide ice sheet. When the tongue collapsed, a huge
amount of water flooded down the St Lawrence River and into the Atlantic. According to ice cores drilled in Greenland, similarly large temperature
oscillations — the Daansgard-Oeschger events that first piqued Broecker’s interest in the 1980s — took place throughout the 90,000 years of the most
recent ice age. It is likely that they were also caused by the ther- mohaline circulation stalling. But in this respect, as in others, the past
may not be a straightforward guide to the present. The consequences of a shutdown could depend on the
climate at the time the cur- rent stalls. Broecker now believes that the cooling in the Younger Dryas and the
Daansgard-Oeschger events came about because the shutdown of the thermohaline circulation was exacerbated
by a positive feedback, in the form of enhanced winter sea-ice formation. An influx of fresh water at high
latitudes encourages the formation of sea ice, because fresh water freezes more easily. Because ice reflects
sunlight, and stops heat from the ocean below reach- ing the atmosphere, spreading sea ice would strongly
amplify cooling due to thermohaline slowdown, especially in winter. Studies of moraines in Greenland and Scandinavia show
that duringtheYoungerDryasthecoolinginsummerswasrela- tively moderate, whereas in wintertime temperatures must have been more than 30 RC lower
than now. It is hard to evaluate the amplifying role of sea ice very precisely. Most coupled ocean–atmosphere models include a sea-ice component, but
the representation is crude and leads to an unrealistic simulation of sea-ice dis- tributions. If this feedback is as important as Broecker
thinks, then the effects of a thermohaline circulation shutdown in a warmed world may be very different from
those seen during the ice ages and their immediate after- math. Today, satellite images show sea-ice cover at a
historic low. In a world that had undergone the degree of warming needed to trigger a thermohaline shutdown in most models there would be
almost none. Rahmstorf speaks for many climate researchers when he rejects the idea that a thermohaline shutdown in today’s climate would lead to a
rerun of the Younger Dryas, in which large parts of Europe were frozen. “You can’t just assume a linear relationship and say that everything will
happenona5Rhigherlevel,”saysRahmstorf.Broeckerstill believes that global warming may have surprises in store, possibly including a collapse of the
thermohaline circula- tion, but he agrees that “the notion that it may trigger a mini ice age is a myth”.
AT: Conveyor Belt - Gulf Stream
Conveyor Belt theory is false – the gulf stream is stable and the rate of warming is too slow
Gibbs 7 (Walter, Bachelor of Science degree from Syracuse University, writer for The New York Times, Time Magazine, the Christian Science
Monitor, Scanorama Magazine, “Scientists Back Off Theory of a Colder Europe in a Warming World,” The New York Times, 5/15/07)
Mainstream climatologists who have feared that global warming could have the paradoxical effect of cooling
northwestern Europe or even plunging it into a small ice age have stopped worrying about that particular disaster,
although it retains a vivid hold on the public imagination. The idea, which held climate theorists in its icy grip for years, was that the North Atlantic
Current, an extension of the Gulf Stream that cuts northeast across the Atlantic Ocean to bathe the high latitudes of Europe with warmish equatorial
water, could shut down in a greenhouse world. Without that warm-water current, Americans on the Eastern Seaboard would most likely feel a chill, but
the suffering would be greater in Europe, where major cities lie far to the north. Britain, northern France, the Low Countries, Denmark and Norway
could in theory take on Arctic aspects that only a Greenlander could love, even as the rest of the world sweltered. All that has now been removed from the
forecast. Not only is northern Europe warming, but every major climate model produced by scientists worldwide in recent years has also shown that the
warming will almost certainly continue. ''The concern had previously been that we were close to a threshold where the
Atlantic circulation system would stop,'' said Susan Solomon, a senior scientist at the National Oceanic and
Atmospheric Administration. ''We now believe we are much farther from that threshold, thanks to improved
modeling and ocean measurements. The Gulf Stream and the North Atlantic Current are more stable than
previously thought.'' After consulting 23 climate models, the United Nations Intergovernmental Panel on
Climate Change said in February it was ''very unlikely'' that the crucial flow of warm water to Europe would
stall in this century. The panel did say that the gradual melting of the Greenland ice sheet along with increased precipitation in the far north were
likely to weaken the North Atlantic Current by 25 percent through 2100. But the panel added that any cooling effect in Europe would be overwhelmed by
a general warming of the atmosphere, a warming that the panel said was under way as a result of rising concentrations of carbon dioxide and other heattrapping gases. ''The bottom line is that the atmosphere is warming up so much that a slowdown of the North
Atlantic Current will never be able to cool Europe,'' said Helge Drange, a professor at the Nansen Environmental and Remote Sensing
Center in Bergen, Norway. Temperate Europe is vulnerable because of its northern perch. The latitude of Britain equals that of frigid Newfoundland.
Norway corresponds to the southern half of Greenland. The annual mean temperature difference of 10 to 20 degrees across the North Atlantic (all
temperature units shown here are in Fahrenheit) is often entirely attributed to the North Atlantic Current. But in recent years, climatologists have said
prevailing winds and other factors independent of the current are responsible for at least half of the temperature anomaly. For the European
warm-water current to stop altogether, the Greenland ice sheet would have to melt fast enough to create a vast
freshwater pool in the North Atlantic. Freshwater dilution on that scale would make the current less dense, preventing its two main strands
from sinking south of Iceland and west of Norway as they must before they can double back toward the Equator on the underside of what is often called
the Atlantic conveyor belt. ''The ocean circulation is a robust feature, and you really need to hit it hard to make it stop,'' said Eystein Jansen, a
paleoclimatologist who directs the Bjerknes Center for Climate Research, also in Bergen. ''The Greenland ice sheet would not only have
to melt, but to dynamically disintegrate on a huge scale across the entire sheet.'' The worst imaginable collapse
would likely take centuries to play out, he said. Any disruption to the North Atlantic Current -- whose volume is 30 times greater than all
the rivers in the world combined -- would thus occur beyond the time horizon of the United Nations climate panel. The last big freshwater dilution is
thought to have occurred 8,200 years ago, when a huge lake atop the retreating North American ice sheet burst through to the Atlantic. For about 160
years, Dr. Jansen said, Europe experienced a severe chill that today would ''stress society quite a lot.'' If the North Atlantic Current weakened 25 percent
this century, fractionally offsetting the effect of global warming, Britain in 2100 would still be about 4 degrees warmer than today, the United Nations
panel estimated. In France, the net warming would be 5 degrees and here in Norway a bit more, depending on latitude. When climate modelers
simulate a 50 percent slackening of the North Atlantic Current, they still see a net warming in those countries.
It is when they completely switch off the current, as they say nature is disinclined to do, that the European
climate cools to a level below that of today. Scientists at the Hadley Center for Climate Prediction and Research near London found that
a shutdown of the North Atlantic Current in 2049 would cause temperatures in most of Britain and Norway to fall from a level several degrees warmer
than today to a level 4 or 5 degrees chillier than today. That would be enough to curtail agriculture sharply. France, though, would still be slightly warmer
than it is now. In a 1998 cover article for The Atlantic Monthly titled ''The Great Climate Flip-flop,'' William H. Calvin spelled out a worst-case scenario
for Atlantic Ocean dynamics and concluded, ''I hope never to see a failure of the northernmost loop of the North Atlantic Current, because the result
would be a population crash that would take much of civilization with it, all within a decade.'' In 2004, the makers of the Hollywood blockbuster ''The
Day After Tomorrow'' imagined the sudden icing over of Manhattan after a disruption in North Atlantic currents. Europe's fate was alluded to by the
implied flash-freezing of the British royal family in Balmoral Castle. Preparing for a cold future has never been high on the political agenda. Perhaps
understandably, European leaders have been more preoccupied with responding to the 2003 summer heat wave that killed 15,000 people across France
and the need for new dike technology to keep the Netherlands from being inundated by rising seas associated with melting ice caps. Richard Seager, a
senior research scientist at the Lamont-Doherty Earth Observatory of Columbia University in Palisades, N.Y., said thatEuropeans should trust what they
feel in the air. ''Britain and western Europe have had one heat wave after another so far this century,'' Dr. Seager said. ''It's phenomenal. The idea that
anyone is worried about a new ice age I find rather odd.''