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Home , Milankovitch cycles

Group: Orange ( Warriors) Team Members: Topic: Position: CON

Topic 1 Introduction:

As many of you are already aware, change is the change in regional climate patterns that impact individuals in their daily lives. Since many human activities have some sort of harmful effect, we tend to conclude that such activities result in enhanced global warming and . Therefore, from our standpoint, climate change is a direct result of human activity, which includes pollution, the burning of fossil fuels, the population’s consumption of trash, and deforestation. If humans did not participate in such activities, we strongly believe that the climate would run its natural course without any obstacles and alterations. 1. FRIEDMAN, THOMAS L. THANK YOU FOR BEING LATE: an optimists guide to thriving in the age of accelerations. New York, NY, Farrar, Straus and Giroux, 2017. a. “Since the industrial revolution there has been a vast acceleration of human impacts on all the ’s key ecosystems and stabilizers… These impacts have become so great in recent decades, and have started to transform the operation of so many individual systems, that many scientists believe they are driving us out of the relatively benign Holocene into a new, uncharted geological , known as Anthropocene.” b. While many associate common fossil fuels with climate change, you may not realize that “everything from the hundreds of millions of tons of cement we’ve poured across the Earth’s surface to radionuclides from atomic testing will be shaping the planet for years to come”. 2. “Climate change causes: A blanket around the Earth.” NASA, NASA, 10 Aug. 2017, climate..gov/causes/. Accessed 18 Sept. 2017. a. “In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world, concluded there's a more than 95 percent probability that human activities over the past 50 years have warmed our planet.” 3. “How do human activities contribute to climate change and how do they compare with natural influences?” European Environment Agency, EEA, 17 June 2017. a. The burning of fossil fuels is the most harmful in regards to climate change since it releases gas into the atmosphere. b. Greenhouse gases and aerosols are part of the Earth’s energy balance and alter incoming solar radiation as well outgoing infrared radiation. This change in the atmosphere results in the warming and cooling of the . c. Volcanic eruptions and solar changes are natural occurrences that impact the climate. However, the European Environment Agency asserts that “the human impact on climate during this greatly exceeds that due to known changes in natural processes.” 4. Throughout this debate, you will be provided with detailed supporting evidence that proves that human activity directly contributes to climate change.

Sub-Topic A: Counter Varying Output 1. “Climate change causes: A blanket around the Earth.” NASA, NASA, 10 Aug. 2017, climate.nasa.gov/causes/. Accessed 18 Sept. 2017. a. Since 1750, the average amount of energy coming from the sun either remained constant or increased slightly. b. If the warming were caused by a more active sun, then scientists would expect to see warmer temperatures in all layers of the atmosphere. Instead, they have observed a cooling in the upper atmosphere, and a warming at the surface and in the lower parts of the atmosphere. That's because greenhouse gases are trapping heat in the lower atmosphere. c. Climate models that include changes can’t reproduce the observed temperature trend over the past century or more without including a rise in greenhouse gases.

Sub-Topic B: Deforestation

Talking Points:

A. Danger of CO2 emissions a. Most harmful that humans directly control

b. Show statistics indicating an increasing amount of CO2 in the atmosphere

B. How do trees/forests help reduce CO2?

a. Give statistics showing the amount of CO2 that a single tree can remove from the atmosphere (talk about the carbon cycle)

b. Put CO2 emissions produced by deforestation into perspective (scientific american) C. Indirect benefits of forests a. Tropical forests act to regulate rainfall and prevent both floods and (Union of concerned Scientists)

D. How humans are directly affecting CO2 emissions through rapid deforestation

a. CO2 is consumed by vegetation so it would be in our benefit to have as many forests as possible b. The rate of deforestation has been steadily increasing over (NPR) c. There is no “simple solution” to deforestation as a huge portion of the world’s forests have already been destroyed and remedial efforts can actually cause even more damage to the local environment (phys.org) d. When trees are cut down, they release stored carbon. This means that not only does deforestation hinder the processing of carbon from the atmosphere, it adds

tremendous amounts of CO2 to the atmosphere as well. Sources: ● “Deforestation and Its Extreme Effect on Global Warming.” Scientific American. N.p., n.d. Web. 20 Sept. 2017. ● “Deforestation Of The Amazon Up 29 Percent From Last Year, Study Finds.” NPR.org. N.p., n.d. Web. 20 Sept. 2017. ● “Studies Show Impact of Forest Management and Deforestation on Climate.” N.p., n.d. Web. 20 Sept. 2017. ● “Tropical Deforestation and Global Warming.” Union of Concerned Scientists. N.p., n.d. Web. 20 Sept. 2017.

1. FRIEDMAN, THOMAS L. THANK YOU FOR BEING LATE: an optimists guide to thriving in the age of accelerations. New York, NY, Farrar, Straus and Giroux, 2017. a. “Scientists estimate that we must maintain around 75% of the Earth’s original forests. We are now down to 62%. 2. Bradford, Alina. “Deforestation: Facts, Causes & Effects.” LiveScience, Purch, 4 Mar. 2015, www.livescience.com/27692-deforestation.html. Accessed 17 Sept. 2017. a. Deforestation is the permanent destruction of forests in order to make the land available for other uses b. Causes: agriculture, trees illegally removed from forests used as fuel, to make more land available for housing and urbanization, and to harvest timber to create commercial items such as paper, furniture and homes c. To make more land available for housing and urbanization To harvest timber to create commercial items such as paper, furniture and homes. d. The deforestation of trees not only lessens the amount of carbon stored, it also releases carbon dioxide into the air. This is because when trees die, they release the stored carbon. 3. Becker, Andrea. “Rates of Deforestation & in the U.S.” Seattlepi, education.seattlepi.com/rates-deforestation-reforestation-us-3804.html. Accessed 17 Sept. 2017. a. It is estimated that prior to European settlement, the United States. was 46 percent forested. European settlers quickly harvested much of the available timber for housing, industry, the creation of railroads and to clear land for farming. By 1907, the U.S. forest cover was reduced to 33 percent. b. The United States lost an average of 384,350 hectares (949,750 acres) of forest each year between 1990 and 2010 4. “Wildland Fire: Wildfire Causes | U.S. National Park Service.” National Parks Service, U.S. Department of the Interior, www.nps.gov/fire/wildland-fire/learning- center/fire-in-depth/wildfire-causes.cfm. Accessed 17 Sept. 2017. a. As many as 90 percent of wildland fires in the United States are caused by humans.

Sub-Topic C: Earth's varying orbit ● a. Through earth's orbit has gone through cycles known as the Milkovich cycles 1. Of the three Milankovitch cycles eccentricity is the cycle that causes the greatest variation of temperatures a. However, we should be going into a period of glaciation but temperatures are rising at an alarming rate. i. 1 degree globally and up to 2 and three degrees in permafrost Russia and Alaska respectively b. These are unusual changes and do not follow the trend that we have recorded over the past hundreds of thousands of years. i. While it is possible it may just be an anomaly a cycle that has repeated throughout history has yet to come and it is time we consider it isn't just natural. b. Eccentricity has been the cause of some of Earth's glaciation periods 1. The last was 120,000 years ago a. The cycles are supposed to last about 100,000 years so are overdue. i. These cycles do take time and there has been variation throughout history it hasn't come close to what we are experiencing. ii. I'm not saying we should be freezing over, but the fact that we are warming at a very fast rate while “historically speaking” we should be cooling is something to consider

c. We may be in an period but we should becoming out of it i. Ice is melting, global temps are on the rise all of this is regular for Earth 1. However, due the the time it is occurring and the rate at which it is happening is what has cause for alarm.

d. Sources ● “Milankovitch Cycles.” OSS Foundation, 19 Feb. 2014, ossfoundation.us/projects/environment/global-warming/milankovitch- cycles. Accessed 20 Sept. 2017. ○ “The long cycle time is about 100,000 years. We can spend around 20% of the cycle in an interglacial and around 80% in an , depending on where we are in these cycle influences.” ● Members of IPCC. “Summary For Policy Makers.” Observed Changes in the Climate System, 2013, pp. 5–20. ○ “There is high confidence that permafrost temperatures have increased in most regions since the early 1980s. Observed warming was up to 3°C in parts of Northern Alaska (early 1980s to mid-2000s) and up to 2°C in parts of the Russian ○ The globally averaged combined land and ocean surface temperature data as calculated by a linear trend, show a warming of 0.85. Almost the entire globe has experienced surface warming ● “Glacial-Interglacial Cycles.” National Climatic Data Center, www.ncdc.noaa.gov/abrupt-climate-change/Glacial- Interglacial%20Cycles. Accessed 20 Sept. 2017. ○ We call with large ice sheets “glacial periods” (or ice ages) and times without large ice sheets “interglacial periods.

Topic 5 Conclusion: ● Volcanic Activity a. Large, violent eruptions may match the rate of human emissions for the few hours that they last, but they are too rare and fleeting to rival humanity’s annual emissions. b. Human activities emit 60 or more times the amount of carbon dioxide released by volcanoes each year. c. Whether from small or large eruptions, volcanic aerosols reflect back into space, cooling global climate. d. Sources ■ Scott, Michon. “Which Emits More Carbon Dioxide: Volcanoes or Human Activities?”Www.Climate.gov, 15 June 2016, www.climate.gov/news-features/climate-qa/which-emits-more- carbon-dioxide-volcanoes-or-human-activities. ● Varying Sun Output a. Over the time-scale of millions of years, the change in solar intensity is a critical factor influencing climate. However, changes in the rate of solar heating over the last century cannot account for the magnitude of the rise in global mean temperature since the late 1970s b. The effect of cosmic rays on cloud formation is too weak to affect the Earth's’ climate in a significant way. c. The 11 year solar radiation cycle, as well as small increase in TSI since 1750, appear in some studies to be correlated with variations in cloud patterns. But these changes in solar energy absorbed by the Earth appear to be far too small to explain the major changes in our climate. d. Sources ■ “How Does the Sun Affect Our Climate?” Union of Concerned Scientists, www.ucsusa.org/global_warming/science_and_impacts/science/effec t-of-sun-on-climate-faq.html#.Wb1WONOGMcg. ● Earth’s a. CO2 causes tropospheric warming in polar regions which melts the ice that is more reflective than ocean water, making Earth’s albedo decreases. b. Sources ■ Pistone, Kristina, and and Ian Eisenman1. “Kristina Pistone.” Proceedings of the National Academy of Sciences, National Acad Sciences, 6 Jan. 2014, www.pnas.org/content/111/9/3322.full#abstract-2. ● Deforestation a. Trees illegally removed from forests used as fuel, to make more land available for housing and urbanization, and to harvest timber to create commercial items such as paper, furniture and homes, which in turn help to contribute to CO2 emissions through the efforts of producing such goods in factories and other steps of product production. b. The deforestation of trees not only lessens the amount of carbon stored, it also releases carbon dioxide into the air. This is because when trees die, they release the stored carbon. c. Sources ■ Bradford, Alina. “Deforestation: Facts, Causes & Effects.” LiveScience, Purch, 4 Mar. 2015, www.livescience.com/27692-deforestation.html. Accessed 17 Sept. 2017. ● Fossil Fuels a. When fossil fuels are burned, they release oxides into the atmosphere, which contribute to the formation of smog and acid rain. b. The presence of excess nitrogen in the atmosphere in the form of nitrogen oxides or ammonia is deposited back onto land, where it washes into nearby water bodies. These excess nutrients contribute to pollution, harmful algal blooms and oxygen-deprived aquatic zones. c. Sources ■ “The Sources and Solutions: Fossil Fuels.” EPA, Environmental Protection Agency, 10 Mar. 2017, www.epa.gov/nutrientpollution/sources-and-solutions-fossil-fuels

Additional Resources https://climate.nasa.gov/causes/ ● Discusses effect https://www.nrdc.org/stories/air-pollution-everything-you-need-know ● Discusses pollution cause and effects and the impact on climate change