Tedford+Global+Dimming

1. The film I viewed was called __ Global Dimming __, released in 2005 and directed by David Sington.

2. The film's central argument is not the familiar one that draws out scientific evidence about global warming's catastrophic ends by itself, instead this film takes into account the protection our pollution has been providing us from global warming. As an environmental engineering student, everything in my training tells me to develop ways to clean the air and free it from particulate matter. This film throws that notion on its head. Apparently, there is sufficient scientific data to support the theory of "global dimming" which is a decreased amount of sunlight reaching the earth. This trend occurred mostly in the 70s and 80s providing sufficient evidence toward droughts, heat waves and other environmental phenomena. The days following 9/11, a climatologist conducted many studies to conclusively find that the temperature range from night to day is increased to almost 1 degree Celsius in the absence of pollution caused by airplane contrails. In the absence of other forms of pollution (by good environmentalist deeds), what would happen to our global temperature? Many of the films scientists argue that by the end of the 21st century, we'll be seeing a 10 degree Celsius increase in temperatures, a model that is quite different from the models of other climatologists who are not considering this "global dimming" effect.

3. This film draws out some strange sustainability problems that are really opposite to what you would come to think of as being good and bad for our environment.


 * __Air Pollution__:** According to this film air pollution is bad and environmentally degrading. However, air pollution has been shielding us from the worst effects of global warming so far. The way water collects around particulate matter of larger size (as compared to particulate matter of smaller size like pollen, naturally occurring) is different and retains moisture that reflects sunlight from entering the atmosphere, therefore not allowing it to become trapped due to greenhouse gases.


 * __Ethiopian Drought:__** The effect of pollution from Europe and the United States may have contributed to the horrific sequence of events leading up to the drought in Ethiopia in the early 1980s. Once again, we have found a way to place the effects of pollution in someone else's backyard. Would people be more compelled to drive less or eat less meat if they knew that they contributed in some way to this awful event?

__**Poor Modeling:**__ I don't feel that scientists take into account all of the factors involved with global warming, and this exact issue is something I've thought about before. How does what we've already done effect climatological models? I have not seen other constituents of our atmosphere taken into account before in this way, especially particulate matter and photochemical smog (volatile constituents). Models need to account for this, and I'm surprised because quite frankly, the major topic in my air pollution course is modeling of air pollutants and how they behave in the atmosphere.

4. There were many compelling portions of this film and a lot of the information was completely new to me, unfortunately. I have thought about the effect of grounding the airplanes after 9/11 before and whether it made a difference on air pollution. I have heard other frequently complain about the connections between respiratory illnesses and airplane contrails, mostly older folks who are non accredited however. In any event, the 1 degree of difference over a three day period really interested and frightened me to an extent. The state of our global affairs never ceases to amaze me, and apart from that our climate is so very sensitive, this should completely kill all political notions that global warming is simply cyclic over large spans of time. Apparently the earth is more sensitive than we think. I was really compelled by other information presented such as evapo-transpiration rates of pan evaporation decreasing. There seems to be a lot of evidence pointing toward the fact that global dimming is real and happening, although not much scientific backing from the community as a whole. For more information/insight see number 9.

5. I wasn't compelled by some of the portions of the film, namely the latter fourth of the film. The film showed a structure similar to that of most environmentally geared films, here is the problem, its getting worse, and worse... slightly more doom and gloom, and the lastly a five-minute segment detailing the "bright-side." I would have appreciated much more positive feedback, because this film challenged my (someday) profession. It became clear in the end, that although the pollution is protecting us, it will kill us eventually also because of the associated health risk. The only information offered to counteract this entire terrible cycle is to decrease CO2 emissions at the same rate as particulate matter. No evidence was offered that this is even something that will counteract what has already begun, very depressing.

6. This film works well with many audiences, namely older people who don't think global warming is "real." I think that this film offers a really well rounded argument about a different issue that is hard to contradict or "not believe in." Younger folks would definitely benefit from viewing this film as well, because honestly we are inheriting this earth, and it is time to scramble together and change the way we are doing things. This generation has the political, business and power to change the way things are going, and its important to have a really good understanding of what exactly is going on.

7. In an effort to reach nonscientific types this film may have left out some much needed information for someone is a little more versed in air pollution and its effects. I would have liked better explanations of particular types of pollution's effects on dimming as well as a better use of charts and figures. Simply telling me that someone made a profound discovery does not accredit it nor prove its validity to me.

8. This film offered little "corrective action" other than reducing CO2 emissions. I can imagine education is an important piece of this, as well as major infrastructural change. Although this film, and many other that I've viewed this semester provide a gloomy outlook, I think that the will and power is there for things to change. More people are aware of their personal CO2 emissions than ever now, and as that knowledge spreads it can only spread further. Between supporting local businesses and farms to riding your bike to work and school I see the changes everyday. I think it all begins with education and a few people starting to change. Aside from that peer to peer interactions really fuel these kinds of social movements. I have to imagine that some part of the "stop smoking" movement happened because smoking became a "dirty habit." What's to say that wasting energy and being unsustainable can't be considered a "dirty habit" as well?

9. This film drew me to find out more about the scientific community's outlook on this issue as a whole, because frankly this is the first I've ever heard of it! After a little research I found out through a scholarly source that in fact this is real, and that brightening has been happening since the mid-80s which for some reason I did not fully comprehend that time line in the film. In a research letter written for a journal of Geophysical Research it states th at, "Recent solar brightening cannot supersede the greenhouse effect as main cause of global warming, since land temperatures increased by 0.8°C from 1960 to 2000, even though solar brightening did not fully outweigh solar dimming within this period." (Wild, 2007) This makes me a little less certain of the weight of evidence provided in the film, as some of it was a little shaky science to me in the first place. Honestly, it was challenging to find another source that did not list "Martin Wild" as a contributor. Finally I came upon another article that said that portions of the world experienced little to no change: Australia; also other places that experienced great brightening over the past 30 years: Japan. (Stanhill, 2006) What I've come to conclude through this film and looking at outside sources is that although this a real phenomena, it is not something that is well understood and therefore I find it hard to produce an opinion about it.

References: Stanhill, G. "Global Dimming: A New Aspect of Climate Change." // Weather // 60.1: 11-14. Web. 11 Nov. 2010. . Wild, Martin, Atsumu Ahmura, and Knut Makowski. "Impact of Global Dimming and Brightening on Global Warming." // Geophysical Research Letters // 34 (2007). // AGU //. Web.