GLOBAL WARMING Joseph Barker, Alisa Applegate, Sherri White, Rick Wagoner, & Jacqueline Miley
Topics • Global Warming Defined • Greenhouse Gases • Causes for Gases • Impacts of Global Warming • Trends in Global Warming • Evidence of Global Warming • KYOTO Conference
Global Warming Global Warming is defined by the NIEHS as: The progressive gradual rise of the Earth’s surface temperature thought to be caused by the greenhouse effect and responsible for changes in global climate patterns.
Global Warming Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases.
Greenhouse Gases While there are numerous causes of global warming, the two main gases involved are • CO2 • Water Vapor They create insulation around the earth holding in the heat. This additional heat warms the earth causing ice caps to melt and other weather phenomenon.
Other Greenhouse Gases Other greenhouse gases: • Anthropogenic emissions • Methane (CH4) • Carbon Monoxide (CO) • Chlorofluorocarbons (CFC) • Hydro Chlorofluorocarbons (HCFC) • Ozone (O3) • Nitrous Oxide (N2O)
Greenhouse Gases While CO2 emissions are the primary source of the greenhouse warming effect, the other gases are measured according to their CO2 equivalent effect
Causes of Gas Production • Carbon Dioxide • Fossil fuel combustion • Deforestation • Methane • Flooded soil crops (e.g. rice) • Fossil fuel mining • Ruminants • Landfills • Organic wastes • Human stimulated eutrophication
Causes for Gas Production • Nitrogen Oxides • Nitrogen fertilizers • Fossil fuel combustion • Chlorofluorohydrocarbons • Release of refrigerant CFCs
Impacts of Global Warming • Elevated temperatures of the biosphere • melting of polar ice • increase in sea level (flooding of major cities) • increase of methane from permafrost • Weather extremes • more rainfall during shorter periods • more evaporation and soil moisture deficiencies • Ecosystem disruption • stress and death of vegetation • migration of animals • Human Health • heat stress • migration of disease vectors
Socioeconomic Issues • Developed countries use most of the fossil energy. • U.S. has 4% of the world population and uses 25% of the energy • Developing countries use about 10% of energy per capita as the U.S. • In the U.S., energy use is 36% for building, 32% for transportation, and 32% for industry • Power plants waste energy ( a 400 MW plant wastes 800 MW of heat energy) • Developed countries have developed on the basis of use of energy and deforestation. How can we ask emerging countries not to do the same?
Trends of Global Warming According to many of the models used to predict the trends in global warming there is expected to be an increase in temperature from 1.4 C to 5.8 C by the year 2100. This would be an increase approximately equivalent to the change in temperature increase between the ice age and today.
Earth’s Climate History Increases of 2.1–5.7oC are predicted due to greenhouse gases: • A 1-1.5o C global average warming would represent a climate not experienced since the beginning of agricultural civilization (6,000 years ago) • A 1-2.5o C warming represents a climate not experienced since 125,000 years ago when small human communities existed. Such a climate seemed to partially disintegrate the West Antarctic Shield, raising sea levels 5-7 m • A 3-4o C warming has not been experienced since humans appeared on Earth (2 million years ago). The last time Earth experienced such a climate was about 3-5 million years ago.
Estimated Effects of Global Warming A recent UN study predicts that a temperature rise of 1.4 C to 5.8 C over the course of the coming century could cause the following: • Sea levels rising by 0.5 – 1.5 m over the next few decades and several meters in the long term • More frequent weather extremes producing floods, avalanches, run-off water availability, soil erosion • Droughts, loss of soil moisture • Reduced precipitation in mid-latitude regions of N. America and Eurasia
Estimated Effects of Global Warming continued… • More stagnant air masses for longer time periods • Severe impact on agricultural productivity worldwide • Die off of unmanaged forests • Reduced stream flows • Increased mortality due to heat stress and spread of infectious diseases
Estimated Effects of Global Warming Flooding Caused by a 75m Increase in Ocean Depth
Evidence for Global Warming • Atmosphere CO2 levels have increased from 230 to 250 ppm (30% since pre-industrial and during industrial age) • Atmospheric methane levels are increasing about 1% per year • Temperature of the earth surface has increased by 0.4oC • Temperature of ocean has increased by 0.5oC • October 6, 1997 was the hottest temperature on record for that time of the year • In 1995, >400 persons died of heat stroke in Chicago
Evidence for Global Warming • Number of days with temperatures below freezing has dropped from 90 in 1990 to 15 in 1997. • Storm and drought conditions are greater than can be explained by normal weather fluctuations • 5-10% increase in precipitation in the 20th century • Floods in the U.S. and China have been 10x more frequent in the past 10 years • Ocean sea level has risen 0.5 cm in last decade, 25 cm in last century
Conference of Parties III 1997, at the Conference of Parties III (COP3), Kyoto, Japan, the Kyoto conference on climate change took place. There, developed countries agreed to specific targets for cutting their emissions of greenhouse gases. A general framework was defined for this, with specifics to be detailed over the next few years. This became known as the Kyoto Protocol.
KYOTO Protocol The objective of the Kyoto Protocol is to stabilize and reduce greenhouse gas emissions, mitigate climate change, and promote sustainable development. The Protocol is historic in that it is the first attempt to achieve international agreements to mitigate global climate change through reduction in GHGs, and the first to employ the flexibility of the global market place for global environmental management.
KYOTO Conference • December 10, 1997 • 1500 delegates from 160 countries • Goal: to arrive at legally binding treaty for global warming mitigation • Most developed countries would increase emissions by 20% with a business-as-usual policy
KYOTO Conference • Pre-conference Goals by Country by 2010 • European Community, -15% C release • Japan, -15% • U.S., -3% • Australia, +18% • Post-conference Goals • Developed Countries, -5 • Australia, +8