Chapter 16. Global Warming
Recommended Article : 【Earth Science】 Earth ScienceTable of Contents
1. Greenhouse Effect
⑴ Greenhouse Effect
① Atmospheric temperature without greenhouse effect : -6 ℃
② Atmospheric temperature considering greenhouse effect : 15 ℃
③ Category 1. Natural greenhouse effect
④ Category 2. Enhanced greenhouse effect
⑵ Earth’s Energy Balance
① 30% of energy from the sun is reflected
② 70% of energy from the sun is absorbed
③ About 30% of emitted energy from the Earth is absorbed by the atmosphere
⑶ History
① Jean-Baptiste Fourier (1827) : Highlighted the similarity between atmospheric and greenhouse glass effects
② John Tyndall (1860) : Measured the absorption of infrared radiation by carbon dioxide and water vapor
③ Svante Arrhenius (1896) : Calculated the effect of greenhouse gas concentrations (5-6 ℃ increase when doubled)
④ G. S. Callendar (1940) : Estimated the warming effect of carbon dioxide from fossil fuels
⑤ Roger Revelle & Hans Suess (1957) : Modeled the impact of carbon dioxide, started measurements
⑷ Optical Window
① Definition **: **Frequency range of light that doesn’t interact with the atmosphere
Figure. 1. Optical Window [Footnote: 1]
② Solar window : Frequency range of light that is absorbed by the Earth’s surface, not the atmosphere
③ Atmospheric window : Frequency range of light not absorbed by the atmosphere and emitted outward
⑸ Greenhouse Gases
① Energy stored through molecular vibration
② Energy stored through electron excitation
③ Earth’s warming potential due to greenhouse gases
④ Magnitude of influence : Water vapor > Carbon dioxide > …
⑤ Greenhouse effect due to increased carbon dioxide : Increases logarithmically
○ Average global temperature with current CO2 levels : 15 ℃
○ Average global temperature with CO2 levels doubled from current : 15 + 1.2 ℃
○ Feedback : 15 + 2.5 ℃
⑥ Methane gas, chlorofluorocarbons : Interfere with atmospheric window, hinder atmospheric emission
⑦ Cloud Effect
○ High clouds : Decrease temperature
○ Low clouds : Increase temperature
⑧ Volcanic Activity : Disrupts energy absorption into the Earth’s surface ⇔ Decreases temperature
2. Global Warming
⑴ Issue 1. Oceans and Greenhouse Effect
① El Niño phenomenon (Origin : Male Child)
Figure. 2. El Niño Phenomenon [Footnote: 2]
140° W corresponds to the central Pacific
○ 1st. Weakening of trade winds near the equator : Temperatures in the western Pacific decrease while temperatures in the eastern Pacific increase
○ 2nd. Central Pacific temperatures higher than normal
○ 3rd. Strengthened convection in the central Pacific
○ 4th. Increased rainfall in eastern Pacific, decreased rainfall in western Pacific
② La Niña phenomenon (Origin : Female Child)
Figure. 3. La Niña Phenomenon [Footnote: 3]
140° W corresponds to the central Pacific
○ 1st. Strengthening of trade winds near the equator
○ 2nd. Enhanced flow of ocean currents from the eastern to western Pacific
○ 3rd. Upwelling of cold deep-sea water near the coast of Peru in the eastern Pacific
○ 4th. Decreased temperatures of Eastern Pacific, increased temperatures in Western Pacific
○ 5th. Increased rainfall in Western Pacific
③ Rising temperatures lead to carbon dioxide release from the oceans
⑵ Issue 2. Glaciers and Greenhouse Effect
① Thermal expansion of glaciers and sea levels
○ Around 0 ℃ : Minimal change in volume
○ Around 5 ℃ : 1/10,000 change per 1 ℃
○ Around 25 ℃ : 3/10,000 change per 1 ℃
○ About 3 cm change per 100 m depth
○ Estimated rise of about 50 cm by the end of the 21st century
○ Sea level rise effect : Antarctic > Greenland > Continental glaciers
② Global climate change due to glacier variations
○ Melting ice poses risk of glacier collapse
⑶ Issue 3. Ozone Hole
① Ozone hole appears primarily in the Antarctic stratosphere during September to October, the beginning of spring in Antarctica
② Role of chlorofluorocarbons
⑷ Issue 4. Desertification
① Climate changes like global warming can contribute to desertification
② Expansion of deserts leads to increased surface reflectivity
⑸ Other Phenomena
① Decreased heating demand
② Positive Effects : Increased plant productivity
③ Cultivation of tropical fruits
④ Irregular rainfall : Efforts to address through reservoirs like Cheonghodae
⑤ Increased mosquitoes and tropical diseases : Need for disease control
⑥ Increased electricity demand in summer : Need for alternative energy generation
⑹ Evidence for Global Warming
① Analysis of past Earth temperatures : Ice cores
② Atmospheric carbon dioxide levels in Hawaii
Figure. 4. Hourly atmospheric carbon dioxide concentration measurements at Mauna Loa
⑺ Counterarguments to Global Warming
① Assertion of exaggerated results by IPCC
② Milankovitch theory : Axial tilt, precession, distance from the sun, sunspots, etc.
③ Assertion of cyclic nature of global temperature change
④ Claim that human contribution to global warming is smaller than natural effects like ocean and volcanic activity
⑻ History of Climate Change Agreements
① 1972 : Discussions on environmental limits (United Nations Conference on the Human Environment)
② 1977 : Discovery of desertification progress
③ 1985 : Discovery of the ozone hole
○ “Large losses of total ozone in Antarctica reveal seasonal ClOx/NOx interaction” (1985. 05. 16)
○ J. C. Farman, B. G. Gardiner, J. D. Shanklin
○ Discovered in a small British research station
○ Hesitated to publish their results for 5 years due to self-doubt
○ “Nimbus 7 satellite measurements of the springtime Antarctic ozone decrease”
○ R. S. Stolarski, A. J. Krueger, M. R. Schoeberl, R. D. McPeters, P. A. Newman, J. C. Alpert (1986. 08. 28)
○ NASA validated the preceding British research
○ Failed to identify major flaws in meteorological data processing algorithms due to authoritarian biases
④ 1992 : Rio Agreement for reduction of carbon dioxide emissions and forest protection
○ Official title : United Nations Framework Convention on Climate Change
⑤ 1997 : Kyoto Protocol with emission reduction targets until 2012
○ Kyoto Protocol : Amendment to the Rio Agreement
○ Resolved to reduce emissions by 5% until 2012
○ Not fully implemented, including the US withdrawal
⑥ 2009 : Copenhagen Accord with recommendations
⑦ 2015 : Carbon emission trading system
○ Introduced in the EU in 2015
○ Carbon emission rights : Rights to emit greenhouse gases (carbon dioxide, methane, nitrous oxide, etc.)
○ Issues with the system
○ Economic downturn due to costs of industrial activity
○ Decreased value of emission rights due to economic fluctuations
○ Difficulty in achieving effects beyond a certain reduction threshold
⑼ Current Status
① Carbon dioxide emissions from residential heating account for 1/5 of emissions from power facilities
Input : 2019.06.23 13:30
Modified : 2020.10.01 20:11