uncertainty_d

=__Uncertainties in the Debate over Climate Change__=

//Montanna, James, Frances & David//

 * __General Topics (explained further below)__**
 * 1) What is the extent of human impact on the environment? How significantly are humans causing/aggravating climate change?
 * 2) Are current rising global temperatures simply a cyclical fluctuation in the earth's history?
 * 3) Is global warming reversible?
 * 4) How great of an issue is climate change?
 * 5) Is there really a link between global warming and the supposed effects (wind currents changing, etc.)? How can we be sure?


 * __Problems in knowing__**
 * no precedent to global warming, so we can't be sure climate change is a problem
 * different authorities support each side (whether or not global warming is a threat)


 * __Explanations of General Topics__**

__Rainfall__ < http://news.bbc.co.uk/2/hi/science/nature/6912527.stm>   
 * 1. What is the extent of human impact on the environment? How significantly are humans causing/aggravating climate change?**
 * Boston University reports scientists are sure that humans caused climate change @ [|http://www.bu.edu/phpbin/news/releases/display.php?id=129]
 * Significantly @ [|http://www.ens-newswire.com/ens/feb2007/2007-02-02-01.asp]
 * Telegraph UK reports that, though the UN believes humans did cause climate change, the UN has downgraded their estimate by 25% @ [|http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/12/10/nclimate10.xml]
 * Studies have shown that Human-Induced climate change has affected global rainfall patterns over the 20th century
 * Areas in the mid-Northern Hemisphere (Canada, Russia, Northern Europe) have become wetter whereas in areas in the southern hemisphere, such as India and parts of Africa, the climate has become more dry
 * Estimated that human activity including the burning of fossil fuels have led to a 62mm increase in annual precipitation trends in the last century in North America and Europe (40-70 degrees North)
 * Estimated that Increase of greenhouse gases and sulphate aerosols in the atmosphere had contributed an 82mm increase in the southern tropics and subtropics (0-30 degrees South), and a 98mm decrease in precipitation in the northern tropics (0-30 degrees North).
 * Other natural factors (Volcanic Eruptions) could also have been causes to the annual shifts in rainfall, but the effect would be relatively minor
 * Trends over last 50 years cannot be explained by natural processes alone
 * Temperature Trends in the Lower Atmosphere, re-analyses the atmospheric data and concludes that tropospheric temperatures are rising.
 * Large uncertainty however
 * In Canada, temperatures are expected to rise 0.2 degrees Celsius per decade
 * Rapid increase in global near-surface temperatures during second half of the 20th century
 * Research indicates that increased carbon-dioxide levels will have a long term effect and remain in the atmosphere for hundreds of thousands of years
 * It is virtually certain that increasing atmospheric concentrations of carbon dioxide and other greenhouse gases will cause global surface climate to be warmer
 * Certain: Mid-continent warming will be greater than over the oceans, and there will be greater warming at higher latitudes. Some polar and glacial ice will melt, and the oceans will warm; both effects will contribute to higher sea levels.
 * What isn’t certain is how fast it will occur, exactly how much will change, and exactly where those changes take place


 * --> __Conclusion__ : Most scientists now agree that humans have caused global warming... To what extent is less certain.**


 * 2. Are current rising global temperatures simply a cyclical fluctuation in the earth's history?**
 * Duncan Steel, a professor at the Joules Physics Lab in the University of Salford, believes they are @ http://www.guardian.co.uk/comment/story/0,3604,854050,00.html
 * ▫ Bert Russ, a former professor at Johns Hopkins, believes they aren't, and are caused by human activity @ [|http://math.nist.gov/~BRust/Gallery.html#Interface2003]
 * ▫ Al Gore's official site for "An Inconvenient Truth", saying no they aren't @ http://www.climatecrisis.net/
 * ▫ Counterpoints to UK documentary "The Great Global Warming Swindle" (that attempts to debunk Gore's "Truth", but is guilty of manipulating information and authorities) @ http://wizbangblog.com/content/2007/03/04/uk-documentary-the-great-globa.php

Argument: It is a Cycle 
 * - Researchers suggest that it is not greenhouse gases that are the cause of global warming, but exactly the opposite
 * n In fact it is the rising global temperatures that are increasing levels of carbon dioxide
 * - People fail to account for the much greater amount of carbon dioxide that enters -- and leaves -- the atmosphere as part of the natural cycle of water exchange from, and back into, the sea and vegetation.
 * - Water is vastly underestimated as a radiation-absorbing gas
 * - Claim: Humans are responsible for less than 5% of atmospheric carbon dioxide
 * - As temperatures rise, the carbon dioxide equilibrium in the water changes, and this releases more carbon dioxide into the atmosphere
 * n Atmospheric carbon dioxide is then an indicator of rising temperatures -- not the driving force behind it.
 * - Because the Arctic Ocean is frozen over, it prevents evaporation of water that would otherwise escape to the atmosphere and then return as snow. When there is less snow to replenish the Arctic ice cap, the cap may start to shrink
 * - As the ice cap melts, the earth warms, until the Arctic Ocean opens again, and when enough water is available for evaporation, snows can replenish the ice cap. When the ice expands, global temperatures will reverse
 * - Due to this, earth can start re-entry into a new ice age
 * - Earth’s current temperature increases may peak within 10-20 years, then descend into a new ice age

Counterpoint: It is Human Causes See #1
 * - Scientists estimate that the amount of carbon dioxide in the atmosphere has increased by about 30 percent since the industrial revolution.
 * - Most fear that if the global temperature continues to rise, it could cause floods, droughts and disrupted food and water supplies.
 * - Increased temperatures may also speed the melting of the polar ice caps, raising sea levels and disrupting the ocean currents that are responsible for our current climate.
 * - Scientists already theorize that global warming has caused stronger hurricanes
 * Conclusion : Global warming is not a cyclical function; graphs representing it as so have been distorted.**

Yes:
 * 3. Is global warming reversible?**
 * Associated Press article: global warming could be irreversible @ [|http://www.commondreams.org/headlines06/0403-01.htm]
 * BostonNews.com reports scientists are unsure when the "tipping point" of climate change will be, i.e. when it will be irreversible @ [|http://www.boston.com/news/science/articles/2006/01/30/scientists_debate_human_effect_on_global_warming/]
 * TIME magazine online gives fun interactive suggestions for how little adjustments around your house CAN combat global warming @ [|http://www.time.com/time/2001/globalwarming/house.html]
 * - We could eventually bring green house gas emissions down (could take very long time)
 * - If we end rapid deforestation and the burning of fossil fuels, the temperature may return to normal. If that happens, the polar ice caps could replenish themselves through accumulated snowfall
 * - Theorists who believe that Global warming is a natural cycle will think that the current temperature increases will reach a peak and begin to descend into a new ice-age

No: < http://www.commondreams.org/headlines04/0315-04.htm> < http://science.howstuffworks.com/question779.htm>
 * - Unless action is taken, the world will be locked into temperatures that will cause irreversible harm
 * - Every molecule of carbon dioxide released today will be in the air for several hundred years
 * - Not realistic that countries will be willing to take the actions necessary to reduce emissions
 * n There are many economic implications of reducing emissions
 * - The five warmest years in recorded weather history have taken place over the last six years
 * - Possible to slow down global warming, but the effects will still be present and still occur, maybe only over a longer period of time
 * - No matter how much governments try to reduce carbon dioxide emissions, it will only be possible to limit the rise in global temperatures to about 2 degrees Celsius (3.6 degrees Fahrenheit) by the end of the century.
 * --> __Conclusion__ : Uncertainty over when climate change will become irreversible; argument of the beard i.e. can there be an exact point where climate change becomes one or the other, reversible or irreversible?**


 * 4. How great of an issue is climate change?**
 * Dr. Bjorn Lomberg believes global warming is happening, but that it's not that bad of a thing; NY Times article @ [|http://www.nytimes.com/2007/09/11/science/earth/11tiern.html?_r=1&ref=environment&oref=slogin]
 * More on Dr. Lomberg; Wall Street Journal article @ [|http://opinionjournal.com/la/?id=110010597]
 * WIRED magazine says a warmer planet wouldn't be so bad @ [|http://www.wired.com/science/planetearth/news/2005/03/66981]
 * Biased source reports long-term negative effects would outweigh short-term positive effects @ [|http://www.effects-of-global-warming.com/effects.html]

< http://www.spiegel.de/international/germany/0,1518,481684,00.html>
 * - A minor temperature drop, with ocean circulation disruption lasting no more than a century and a half (a blink of the geological eye). This would be a problem, to be sure, but not the global civilization-disrupting event seen in some scenarios.
 * - Other research suggests that a far worse result is also possible.
 * - Ages may come where there are more equable and better climates, making poor harvests and famine a thing of the past
 * - Rising temperatures might result in higher crop yields and more tourism (Canada, Russia) in some places
 * - There will be losers and winners as a result of climate change (more severe in Scandinavia, less so in the Mediterranean)
 * - A warmer climate helps promote species diversity
 * - Effects such as rising sea temperatures will occur over decades and give people time to react
 * - Tale of melting south pole = fiction

--> Short-term positive effects include less deaths caused by severe cold, a larger water supply due to the melting icecaps, and/or more CO2 in the atmosphere leading to more plant growth and agricultural production. --> However, this would be balanced out by, over time, diseases spreading easier due to the increase of heat, no icecap water supply left, and loss of biodiversity due to climate change.
 * --> __Conclusion__ : Though there are both positive and negative effects of climate change, only the negative gets publicity so that people are incited to action.**

There is no way to be sure that instances such as hurricanes (Katrina) have been caused directly by effects of global warming
 * 5. Is there really a link between global warming and the supposed effects (wind currents changing, etc.)? How can we be sure?**
 * FOXNews.com reports there's "No Uncertainty" (meaning it's absolutely certain) @ [|http://www.foxnews.com/story/0,2933,184147,00.html]
 * EPA investigates the effect of global warming on human health @ http://www.epa.gov/climatechange/effects/health.html


 * - Earth can follow an infinite number of possible weather sequences
 * - Impossible to know unless we turn back time and choose not to increase concentration of greenhouse gas emissions as much as we did
 * - Weather events will always come about as a result from a combination of deterministic factors, either from greenhouse gases or slow natural climates, or from stochastic factors (pure chance)
 * - Weather follows semi-random nature

However
 * - Hurricanes tend to become more destructive as ocean temperatures rise
 * - An unchecked rise in greenhouse gas concentrations will very likely increase ocean temperatures further, ultimately overwhelming any natural oscillations

< http://www.realclimate.org/index.php?p=181>

//Greenpeace UK// -- [|http://www.greenpeace.org.uk/] //United Nations Framework Convention on Climate Change// -- [|http://unfccc.int/2860.php] //TIME magazine// investigates effects of global warming @ http://www.time.com/time/2001/globalwarming/splash.html
 * __More Important Links__** __(different authorities)__