Climate CPR Paper
by
The Professor
Introduction
The climate of the earth is a topic that everyone should be interested in. We take vacations in nice places, try to live where the environment is healthy and beautiful. Even more important is the ability of our farmlands to grow the food that we depend on. The health of the ocean environment is important because the phytoplankton generate a major portion of the oxygen in the atmosphere and are at the base of the food chain. Without phytoplankton, there would be no fish in the ocean and a major source of food for the world's population would be gone [:(Cmnt by william prothero: Not a bad introduction, but it doesn't tell what the topic of the paper is, just generally chats about the importance of the subject. ):] .Causes_of_Climate_Change
The major factors that affect the earth's climate are shown in the {link: c_GHFig6LabBk.jpg}figure from chapter 6 of the Oceanography lab book. This figure shows the major atmospheric influences. The atmosphere causes the greenhouse effect, which warms the earth above the temperature that it would be if there were no atmosphere.The most important greenhouse gas is CO2 because it is put into the atmosphere by human activity. It is called "anthropogenic" because of this. CO2 increases cause more heat to be trapped by the atmosphere, warming the planet. The concentration has increased drastically since the 1800's, coincident with increases in global energy production. CO2 stays in the atmosphere for about 100 years.
Another important greenhouse gas is water vapor. It is controlled mostly by evaporation of surface water, and leaves the atmosphere through rain or snow. Although its effect is much stronger than that of CO2, its short residence time of a few days makes it less of a long term problem. It changes in response to other factors. An example might be that a warmer earth causes more evaporation, which increases greenhouse warming due to more low clouds, which then causes more evaporation. Another possibility is that increased evaporation causes more high clouds, which reflect more sunlight and tend to cool the planet. The first effect is a positive feedback while the second effect is a negative feedback [:(Cmnt by william prothero: Quite a few parameters that cause climate have been ignored. For example, the distance between sun and earth haven't been mentioned, and that's one of the most important factors.Only two greenhouse gases have been mentioned. ):] .
Earth_Climate_History
The earth's temperature over the last 400,000 years is shown in {link: c_Temp400Kyrs.jpg}figure 2. The record shows the last 4 ice ages. Another plot ({link: c_Vostok1.jpg}figure 3) shows the temperature for the last 160,000 years. Notice that the CO2 and methane go up and down together. The temperature varies by 1-2 degrees over a thousand year time scale, but ice age conditions vary by about 6 degrees [:(Cmnt by william prothero: This is a pretty minimal amount of data. References to the data are not included and nothing is said about how the temperatures are determined, like from ice cores, or tree rings. ):] [:(Cmnt by william prothero: It's good that the author mentioned the actual values of temperature changes. ):] C.Historical_Climate_Change
{link: c_temp1880.jpg}Figure 4 shows the historical measured temperature changes for the last 200 years. The global temperature is measured using land based thermometers at weather stations, reports from ancient writings at monastaries, and tree rings. The historical temperature actually goes back about 1,000 years. {link: c_Temp1Kyr.jpg}Figure 5 shows a plot of this. You can see that the temperatures vary up and down, but show spike of about 0.8 degrees in the last 200 years. The recent precipitous temperature rise is called by some, the "hockey stick" dependence of temperature on time.
Various stakeholders argue that the observed temperature change is wrong. Two scientists, McIntyre and McKitrick, have attempted to publish work asserting that the "hockey stick" temperature rise is not real (Schmidt and Amman, 2005). McIntyre works in the mining industry and McKitrick is an economist. Their paper was rejected by Nature as scientifically unsound and Schmidt and Amman have done numerical simulations to show that their work is indeed correct [:(Cmnt by william prothero: The data descripions are weak. There are no references on where the data came from, but some mention of land temperatures and tree rings. Nice discussion of an alternative view. ):] .
Climate_Change_Scenarios
The web site of the US Global Change Research Program (USGCRP, 2003) lists a number of climate change possibilities for the US. Among them are:Note that the above impacts are predicated on the prediction of a warmer climate. If the melting of Arctic ice shuts down the heat conveyor belt and initiates a new ice age, all bets are off.
Another change, discussed in the talk of Erin Ricketts (GS-4w TA and graduate student researcher) is that the pH of the ocean is increasing due to the increased CO2. This will acidify the ocean, dissolve the coral reefs, and make the ocean uninhabitable for many species of sea life [:(Cmnt by william prothero: Good discussion of a climate change scenario from a single government source. The only criticism is that it is focussed on the US exclusively, and the global climate change scenarios will also be important and will affect the US.):] .
Policy_Recommendations
What can I do about climate change? What should governments do? What should corporations do? First, we need to be sure that climate change is occurring and is due to rising emissions of CO2. I believe that this has been shown. Most climate scientists also agree that it is very likely that we are affecting the climate of the globe and that changes are coming. We can't accurately predict what the changes will be, but they range from not so bad to pretty gruesome.The Kyoto treaty requires all signatories to roll back CO2 emissions to below pre-1997 levels. The US will not sign it because it may hurt the economy and politicians claim it unfairly penalizes the US, which emits about 1/3 of the total global CO2. The European Union has instituted carbon emissions trading, where each industry gets a certain amount of CO2 emissions allotted. If the exceed their allotment, they must purchase emissions "credits" from other industries that emit less than their allotment. This creates an economic incentive to reduce emissions.
As an individual, I can give money to environmental organizations promoting CO2 reduction, write letters to my congressperson, and write letters to the editor. Voters need to make noise [:(Cmnt by william prothero: \It would have been good to discuss the Kyoto protocol in more detail.):] !
References
4 Dec, 2004. False Claims by McIntyre and McKitrick regarding the Mann et al. (1998) reconstruction. link: http://www.realclimate.org/index.php?p=8
Vostok Data:
Barnola, J. M., D. Raynaud, Y. S. Korotkevich and C. Lorius, 1987, Vostok ice core provides 160,000-year record of atmospheric CO2, Nature, 329, 408-414.
CO2 since 1880
http://www.fs.fed.us/ne/delaware/biotrends/trends_climchange.html
USGCRP: http://www.usgcrp.gov/usgcrp/Library/nationalassessment/overviewimpacts.htm
National Academies:
http://www4.nationalacademies.org/onpi/webextra.nsf/web/climate?OpenDocument
Kyoto Protocol:
(http://environment.about.com/od/kyotoprotocol/a/aa090402a.htm) [:(Cmnt by william prothero: Some of the URL's and references are not noted in the text. All references must be linked to specific text phrases. ):]
Figure 1. Diagram of atmospheric factors that influence the earth's climate. {fig: c_GHFig6LabBk.jpg}
Figure 2. {fig: c_Temp400Kyrs.jpg}
Figure 3. Last 160,000 years from Vostok ice core. {fig: c_Vostok1.jpg}
Figure 4. Annual mean temperature anomalies since 1880. {fig: c_temp1880.jpg}
Figure 5. One thousand years of temperatures, from tree rings and modern measurements of temperature. {fig: c_Temp1Kyr.jpg}