Monday, February 2, 2009

IPCC Summary for Policymakers - Urbanowski

In 2007, the Intergovernmental Panel on Climate Change (which that year shared the Nobel Peace Prize with Al Gore) released a summary report on the causes of climate change and its potential effects in the future. While our class as a whole is focusing on the overall impact of climate change, it's a good idea to look at the science behind these issues to give us a better idea of why these issues are so prevalent. The Intergovernmental Panel on Climate Change report is a good scientific introduction to these issues.
Let's begin with the causes of climate change. Carbon dioxide is considerably more prevalent now than it was in the pre-industrial period (379 parts per million in 2005, a 35% increase from pre-industrial times), and increased use of fossil fuels is seen as a leading cause of this increase. More profound, however, is the 148% increase in methane in 2005 versus the pre-industrial era.

After establishing that these increases have taken place, they then establish that the temperature of the earth is also increasing. "Eleven of the last twelve years (1995–2006) rank among the 12 warmest years in the instrumental record of global surface temperature," the report says. Sea temperatures are also increasing, causing seawater to expand; this contributes to rising sea levels (as does the melting of glaciers near the poles). Sea levels expanded at a rate of 3.1 millimeters per year from 1993 to 2003.

In fairness, the report does show that increased agriculture and use of fossil fuels is responsible for higher levels of methane and CO2; however, its attempt to establish causality between these higher levels and the increase in temperatures is not as stellar. The report's use of terms such as 'likely' and 'unlikely' is not as convincing to me as the evidence they offer to make other claims. This does not mean that I disagree with it; however, there seems to be a lack of consistency in the presentation of their evidence from topic to topic.

In the future, according to the report, we can expect to see increases in the prevalence of greenhouse gases. This is 'likely' to cause the earth to get warmer in the future. Because of that, seas are expected to rise while wind patterns are expected to change. With much of the world continuing to develop industrially, we can expect these patterns to continue at a more rapid rate.


  1. There is no doubt that the enviornment is in jepordy due to human impacts and the report did a good job at relaying the message, but I did also feel the report was lacking consistency and even jumping around a bit. The interesting thing was their charts and graphs only went back to the early 1900s; they didn't bother to mention how the world has always had natural cycles.
    Temperatures and sea levels go hand in hand; they have been rising and falling for hundreds of thousands of years. Carbon levels rise and fall naturally due to volcanic activity and fires. The Earth is a closed system; one place is going to dry up and another is going to flood out.
    The paper was interesting and very informative. It does deal with modern day issues but I feel they need to go deeper in their history. It is easy to make somebody believe something when there are big pictures (graphs)that can easily be read right in front of them.

  2. It is probably unanimous in saying that this article is showing the ill effects of human activity on the world. It gives good scientific calculations without much hint of any kind of bias. It is clear that many scientific and mathematical calculations were done in order to produce this report.

    I can see why one of the reviewers was rather put off by the "likely" and "unlikely" terms that were used in their prediction. It seems rather shady in some sense, but if you look at the footnotes on one of the pages it tells you that these labels are based on a certain percentage chance that they are related. That makes sense to me, but they could have just used the percentages in the actual article.
    The previous commenter makes a good point by addressing the fact that the authors of this article did not go back before 1900 or and 1850 when talking about these cycles of warming, sea level and various gas levels in the world. I agree that human activity has had a large impact on the Earth, but there has been shit happening that has affected the Earth for billions of years. They do mention some about various extraneous variables that has contributed to warming and everything else, but not much.
    One thing I thought was interesting about the article is their various metaphorical situations that try and predict future global harms if things were to pan out that way. Lets just hope that we go down a more sustainable path.
    One question I had about this article. Who are these policy makers that this article is written for? And are we going to see any of this rather disturbing evidence taken into consideration when certain policies are made? I am thinking that we will not hear too much about this kind of stuff except for little 5 minute blurbs on the news.

  3. While I could see that much math and science went into the report, I was curious about the source of the information that was studied. I was particularly put off by some of the graphs that started the numbering on the vertical axis below zero. I would like to know more how these graphs work and who the policy makers are that use this document. I wonder this because of the use of Celsius when American's use degrees Fahrenheit and if they looked at the graph someone might not realize the difference between these two measurements.
    I completely agree that the use of "likely, unlikely, more likely than not" and such phrases give the report a rather pedestrian feel because of the lack of distinction between the phrases.
    If the report had reflected what normal trends for climate would be I would have been able to more clearly understand the stark differences in what should be happening compared to what is. Also, in doing this it would address the people that say the Earth has always gone through periods of warming and cooling.