Global+Dimming

Chris Knortz 10/14/2011 Title: Global Diming Director: BBC Horizon

2. What is the central argument or narrative of the film? After decades of know climate change as a result of industrial activity evidence is being found to show that his activity has created a global diming effect. The reduction is sun light to the surface of the earth has been able to mask the true effects of large increases in greenhouse gasses in the atmosphere.

3. How is the argument or narrative made and sustained? The film presents a great deal of scientific evidence to support the argument of global dimming. The first example was the nationwide temperature increase after the terrorist attacks of September 11th. This was a caused by the reduction in the air pollution form commercial air travel. One study showed that there was a 1 degree C jump in the daily temperature range across the nation while the flights were grounded. Particulate and con trails, the vapor trail left behind in the sky by planes, were absent during this three day period allowing the full force of the sun to reach the earth and not be reflected by particulate. Long term studies on global dimming were also shown in the film. Researchers in both Israel and Germany conducted separate studies looking into the strength of the sun at the earth’s surface. In both gases it was found that the sun light reaching the earth’s surface was about 10% weaker that it was in previous decades. This decrease is solar energy on the surface of the earth was then shown to create a complicated and intricate array of problems.

4. What sustainability problems does the film draw out? One section of the film showed some of the effects of global dimming on the climate. The most striking one was a look at the famine in east Africa in the 70’s and 80’s. After the theory of global dimming gained support in the scientific community researchers began to make a correlation between the drought in that region and the dimming effect. For several years the seasonal rainy season failed to come, this normally is a shift in the weather pattern over the equator that shifts forward bring rain to that region of eastern Africa. During the 70’s and 80’s the ocean temperature were not high enough to allow the sift in the weather pattern keeping the rain over the equator. This was one situation where the yearly weather pattern was disrupted causing the deaths of thousands of people. Such a weather disruption could happen in other areas of the world that relight on a monsoon season for most of their water. Much of the population of Asia is supported by similar weather systems. A disruption here would affect billions of people. At the end of the film a future was discussed in which the world was allowed to continue on its present path of warming. This involved people continuing to produce greenhouse gasses while reducing the particle pollution. This has been done today, the levels of particle pollution have been shown to be decreasing in many areas. A significant reduction in particle pollution will only worsen the future situation, a true solution to pollution is needed. Currently global dimming has the effect of keeping the world temperature down while greenhouse gasses work to raise it. Remove the cooling effect and the world could see an even more dramatic increase in temperature that is being seen now.

5. What parts of the film did you find most persuasive and compelling? Throughout the film there was a great deal of scientific information presented. This was information that was gathered by different independence researches around the world conducting different tests. In the end the research showed a worldwide phenomenon of global dimming. The fact that this was shown through several different tests around the world gives the theory a great deal of creditability. One of the more interesting examples was the water pan evaporation records in Australia. These records had been kept by farmers around the world for over 100 years. It was shown that there was a significant reduction in the amount of water that evaporated form the pan each year. This information was then compared to light intensity studies done around the world and it was found the decrease in total solar energy matched.

6. What parts of the film were you not compelled or convinced by? The idea that the strength of the sun on the surface of the earth is weakening is not a popular or well-known concept. This was even admitted in the film. When the researches in both Israel and Germany published their findings they were ignored by their colleagues. A global situation that affects climate in such devastating ways should have more scientific and political attention. However this problem is tied into global warming, if global warming is eliminated the catastrophic effects of global dimming will most likely be eliminated. With no further greenhouse gas pollution there should be no further particulate pollution.

7. What audiences does the film best address? This issue has the potential to change the lives of every person on the planet. For many however the decision to reduce the production of particle pollutants is out of their hands. The film best addresses those who have the power to change their situation. The film exposes the long lasting and diverse consequence on innocent people of industrial pollution. Individuals, especially in the Western world, have the power to make a difference in regards to this problem with their everyday small decisions. A lifestyle based of sound decisions can make a difference to the global climate.

8. What could have been added to this film to enhance its environmental educational value? During the section at the end of the film that looked at the devastation caused by global warming in the future without the balancing effects of global cooling there were only stories of severe drought and heat. The film should have looked at the areas that also have an increase in the potential for flooding. With increased temperatures there will be more volatile weather, meaning more rain in some places. A look at this side of the future of the world climate could have given a more balanced view of the potential future.

9. What kinds of action and points of intervention are suggested by the film? The end of the film gives examples of the future devastation that is possible if nothing is done to curb the production of greenhouse gasses and particle pollution. Some of the scientific models show the earth’s temperature increasing by 6 degrees C by the end of the century. Such an increase would make some areas of the world uninhabitable, and others would become scorched deserts which were once lush temperate zones. One of the researchers from the Maldives study calls for an immediate reduction in the use of carbon dioxide fuels to produce energy. He admits this would force drastic changes in the way of life for many people, however he points out this may be the only solution to allow the world to stay inhabitable.

10. What additional information has this film compelled you to seek out? The scientific reasons behind global dimming sound very similar to the principals of climate engineering. This involves seeding the stratosphere with chemicals designed at reflecting the sun’s rays back to space, there by cooling the atmosphere. This has always been seen as a risky proposition. However it is exactly what is happening now with global dimming, the sun’s rays are being reflected acting to counter global warming. An article in Wired Magazine looks at the long term potential of deliberate climate engineering. Once such a system was put in place to reduce the earth’s temperature it could never be stopped. Such a system would be able to stabilize the temperature, however the carbon dioxide would still be in the atmosphere. Shutting down the system would allow the global temperature to rise extremely quickly causing severe damage to the biological systems of the earth. During the film the claim was made several times that the particulate matter in the atmosphere has been decreasing since the late 1980’s. Air quality standards in in developed nations have motivated this change because of health problems associated with high levels of particulate. The EPA has tracked these levels across the U.S. It can be seen that the levels of particulate across the nation have decrease by 27% in the past 10 years. This is an improvement of the global environment but without any significant reduction in greenhouse gasses these improvements will be meaningless to the future environment.

Particulate Matter, “National Trends in Particulate Matter Levels” EPA.Gov February, 2011. []

Smalley, Eric. “Climate Engineering is Doable, as Long as We Never Stop” Wired Magazine, June 2007 []