Sbsp affirmative- arl lab- ndi 2011
AT: CO2 Ag- Prefer our ev
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- AT: Ice Age
- The uncertainty in predicting the ice age means you defer to short term implications
- No impact – tech can solve the ice age
AT: CO2 Ag- Prefer our evPrefer our evidence – more recent studies that reflect field conditionsMittelstaedt, ‘6 - Environment reporter at the Globe and Mail [Martin, The Globe and Mail, “Harvest yields global warning; Greenhouse gases won't offer expected benefit, study shows,” Lexis, DS] In the long list of worries over the possible negative consequences of global warming, agriculture has usually been one of the only bright spots, with most researchers confident that as the planet's climate heated up, crops would be relatively unaffected or might even increase. This optimistic view has been based on hundreds of laboratory experiments showing that crucial crops, such as wheat, corn and soybeans, when exposed to higher concentrations of carbon dioxide released through the burning of fossil fuels, respond much like they've been given an extra dose of fertilizer. The plants experience more robust growth and have sharply higher yields. These plant experiments, conducted mainly during the 1980s, led most researchers to forecast that the disruption global warming might cause to agriculture through changes in temperatures and precipitation patterns would be offset by improved crop yields, as plants thrived in a world with higher levels of carbon dioxide. But that rosy view, which has been incorporated into projections made by influential bodies such as the United Nations Intergovernmental Panel on Climate Change, may be unjustified, says a new research paper in the journal Science that found the beneficial effect of rising carbon-dioxide levels has been significantly overestimated. The paper, based on experiments using plants grown under actual field conditions rather than in the more controlled enclosures used for the earlier estimates, found that while most yields increase as the amount of carbon dioxide in the air rises, the benefits were only about half the amounts that led to optimism about the impact of global warming on farm output. Prefer recent models and better tech–McCarthy, ‘5 - Environment editor at The Independent [Michael, 4/27/2005, The Independent, “Climate change poses threat to food supply, scientists say,” Lexis, DS] Worldwide production of essential crops such as wheat, rice, maize and soya beans is likely to be hit much harder by global warming than previously predicted, an international conference in London has heard. The benefits of higher levels of the main greenhouse gas, carbon dioxide, will in fact be outweighed by the downsides of climate change, a Royal Society discussion meeting was told yesterday. It had been thought that the gas might act as a fertiliser to increase plant growth. Rising atmospheric temperatures, longer droughts and side-effects of both, such as higher levels of ground-level ozone gas, are likely to bring about a substantial reduction in crop yields in the coming decades, large-scale experiments have shown. The two-day meeting, entitled Food Crops in a Changing Climate, is focusing largely on tropical countries where most of the world's food is grown, and where people are most vulnerable to climate change. It is bringing together leading scientists in the fields of meteorology, climate science and agriculture to report on the latest research, including growing crops in experimental conditions in the open air that simulate advanced global warming. Previously, such experiments had taken place in closed chambers, and these had suggested that the 'fertilisation' effect of rising CO2 would offset the detrimental effects of rising temperatures and drought incidence on crop production. But, a new technology known as Face (Free-Air Concentration Enrichment) is allowing treatment of large areas of crop with elevated levels of CO2 and ozone, and these experiments have painted a very different picture. 'Growing crops much closer to real conditions has shown that increased levels of carbon dioxide in the atmosphere will have roughly half the beneficial effects previously hoped for in the event of climate change,' said Steve Long, from Illinois University. 'In addition, ground-level ozone, which is also predicted to rise but has not been extensively studied before, has been shown to result in a loss of photosynthesis and 20% yield loss. Both these results show that we need to seriously re-examine our predictions for future global food production, as they are likely to be far lower than previously estimated,' Professor Long said. Additionally, studies in the UK and Denmark show that just a few days of hot temperatures can severely reduce the yield of major food crops such as wheat, soya beans, rice and groundnuts, if they coincide with the flowering of these crops. These results suggest that there are particular thresholds above which crops become very vulnerable to climate change. On a more positive note, the meeting also highlighted new developments in forecasting techniques, the basis of which can act as early warning systems of famine. The techniques incorporate a climate prediction model with a model that simulates crop growth under varying environmental conditions. AT: Ice AgeDefer aff – contradicting scientific claims mean it’s better to stop emissions while we still canSpotts, ‘4 - staff writer of The Christian Science Monitor [Peter N. Spotts, staff writer of The Christian Science Monitor, “Ice age to warming - and back?” http://www.csmonitor.com/2004/0318/p13s01-sten.html Mar 18] The Little Ice Age and "the 8,200-year event" are not exactly household terms. Once only a handful of climate scientists puzzled over these episodes of abrupt climate change. Now, the topic is getting close scrutiny from the Pentagon, the halls of Congress, and even Hollywood - where a disaster movie set for release in May depicts a sudden deep freeze. One reason for all the interest? While policymakers have worried long and hard about global warming, which might raise Earth's temperature 1.4 to 5.8 degrees C by century's end, a growing body of evidence suggests natural forces could just as easily plunge Earth's average temperatures downward. In the past, the planet's climate has changed 10 degrees in as little as 10 years. That may not sound like much. But the last time the planet was 10 degrees colder, it was still in an ice age. "There's the very real potential of the climate system changing dramatically and rapidly" in ways that lie outside modern human experience, says Mark Eakin, who heads the paleoclimatology program of the National Oceanic and Atmospheric Administration (NOAA). The possibility of a sudden freeze doesn't mean mankind can relax efforts to curb global warming, many scientists warn. Indeed, given the complexity of Earth's climate, human activities that spew greenhouse gases into the atmosphere may increase the potential for an abrupt cooling. For example: Regional and global climates have undergone quick and dramatic changes even after what would appear to be only gentle prodding by natural influences, Dr. Eakin says. In many cases, that prodding has been far less severe than the changes humans have wrought via industrial emissions of carbon dioxide. "In the absence of better knowledge, we have to assume that humans are making abrupt climate change more likely - not because humans are worse than nature, it's just because we're changing the system," says Richard Alley, a Penn State University paleoclimatologist. Dr. Alley led a 2002 National Research Council panel that examined abrupt climate change and laid out recommendations for research priorities and possible adaptation strategies. The uncertainty in predicting the ice age means you defer to short term implicationsRevkin, 8 environment reporter at the New York Times, 2008 [Andrew C, “Skeptics on Human Climate Impact Seize on Cold Spell,” March 2, New York Times, http://www.nytimes.com/2008/03/02/science/02cold.html?_r=1&ref=science&oref=slogin] It may seem that human-driven global warming, although perhaps a disaster on the scale of centuries, may be a good thing in the long run if it fends off the next ice age awhile. But many climatologists note that the complex interplay of greenhouse gases, orbital shifts and other influences on climate remain poorly understood. In fact, some experts say, there is a chance that human-induced warming could shut down heat-toting ocean currents that keep northern latitudes warmer than they otherwise would be. The result could be a faster descent into glacial times instead of a delay. No impact – tech can solve the ice ageHansen, ‘7 head of NASA Goddard Institute and professor of Environmental Sciences, Columbia University [James, 6/25/2007, “How Can We Avert Dangerous Climate Change?” delivered as a private citizen to the Select Committee on Energy Independence and Global Warming, United States House of Representatives, http://arxiv.org/pdf/0706.3720] Thus the natural tendency today, absent humans, would be toward the next ice age, albeit the tendency would not be very strong because the eccentricity of the Earth’s orbit is rather small (0.017). However, another ice age will never occur, unless humans go extinct. Although orbital changes are the ‘pacemaker’ of the ice ages, the two mechanisms by which the Earth becomes colder in an ice age are reduction of the long-lived GHGs and increase of ice sheet area. But these natural mechanisms are now overwhelmed by human-made emissions, so GHGs are skyrocketing and ice is melting all over the planet. Humans are now in control of global climate, for better or worse. An ice age will never be allowed to occur if humans exist, because it can be prevented by even a ‘thimbleful’ of CFCs (chlorofluorocarbons), which are easily produced. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 1.74 Mb. Share with your friends:
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