The Atmosphere. Chemical Composition. Climate. Processes that remove materials. The Atmosphere, Climate Change, and Ozone UAU102F 10/28/2012

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1 The Atmosphere The Atmosphere, Climate Change, and Ozone Composition Layers Chemical composition Processes that remove materials Climate Change Ozone Chemical Composition Ninety percent of the weight of the atmosphere lies within the first 12 km above the surface Nitrogen 78% Oxygen 21% Argon 0.9% CO % and some traces of others such as ozone and methane. Processes that remove materials Sedimentation: particles settle out as a result of the gravitational attraction to earth. Rainout. Precipitation flushes material from the atmosphere. Rainfall slightly acidic H 2 CO 3 Oxidation: Oxygen is chemically combined with another substance. Photodissociation: Solar radiation breaks down chemical bonds e.g. ozone in the atmosphere may break down to O 2 due to photodissociation. Climate Climate: the representative or characteristic atmospheric conditions for a region on Earth. Conditions over a long period. Precipitation and temperature Microclimate The climate of a very small local area Weather Day to day changes. ThrosturTh@hi.is 1

2 Climate Change Major climatic changes have occurred during the past 2 million years Appearances and retreats of glaciers During the past 100 years, the mean global annual temperature has increased by 0.5 degrees Celsius Climate Change: Global warming A natural or human induced increase in the average global temperature of the atmosphere near the earth s surface. 4 factors affect this feature Solar Activity Reflectance Retention of heat by atmosphere (GhG) Cloud cover (evaporation and condensation) Solar Activity Reflectance ThrosturTh@hi.is 2

3 The Greenhouse Effect Greenhouse Effect The process of trapping heat in the atmosphere Water vapor and several other GH gases Greenhouse Gasses Water vapor, CO 2, CH 4, CFCs, N 2O Global warming potential; heat trapping ability compared to CO 2 Radiative forcing Function of concentration and heat trapping ability GWP o A measure of how much a given mass of greenhouse gas is estimated to contribute to global warming. o Is a relative scale which compares the gas in question in that of the same mass of carbon dioxide (with GWP=1) LT 20 yrs 100 yrs 500 yrs Methane ,6 Nitrous oxide HFC HFC-134a SF Carbon Dioxide GWP equal to % Radiative forcing, to 380 ppm in 140 years Concentration increased due to e.g.: Fossil fuels Deforestation Methane GWP % Radiative forcing 0.48 Increased 154% ppb Emitted from: Rice Paddies Lifestock Termites Coal and gas Landfills Nitrous Oxide GWP 298 5% Radiative forcing 0.15 Increased 16% Emitted from: Fossil fuel combustion Fertilizer use CFC s (chlorofluorocarbon) GWP Radiative forcing Emitted from use in: Refrigerators Spray cans ThrosturTh@hi.is 3

4 Global Cooling Albedo: surface reflectivity of the sun s radiation Aerosols Increase planetary albedo Sulfates Increase planetary albedo Provide surface for cloud formation Positive and negative loops Difficult to predict what exactly will happen Negative and Positive feedback cycles affect the atmosphere Negative - stabilizing Positive - self-enforcing Negative Positive Effects of Climate Change Changes in climatic patterns Temperature change Change in precipitation Increased extreme weather events Rise in sea level Changes in ocean currents Changes in biosphere Changes in yield Possible extinction events Increased incidence of tropical diseases ThrosturTh@hi.is 4

5 The future emissions will continue to increase A1. Homogenous world. Rapid economic and population growth, rapid introduction of new technologies convergence. A1FI (Fossil intensive), A1T (non-fossil energy sources), A1B (balance) A2. Heterogenous world. Self reliance, preservation of local identities. High population growth than in A1, as fertility rates are maintained. Lower econ. growth than in other scenarios. B1. Convergent world, with population growth as in A1, but rapid change in econ structure towards service economies. Dematerialization, technological change. B2. Local solutions - lower population growth than in A2. Intermediate levels of economic development,, less rapid technological change than in A1 and B1. Oriented towards environmental protection and social equity. IPCC scenarios Summary GHG emissions will continue to increase in all scenarios IPCC scenarios show 25-90% increase in 2030 compared to /3 increase from Non-Annex I countries. IPCC scenarios show 40% decline to 250% increase in 2010 compared to Stabilization targets Our Response Stabilization of CO 2 concentrations in the atmosphere. Stabilization of target mean global temperature. Timing of emissions reductions depend on the stringency of stabilization target. How to get there? Mitigation! ThrosturTh@hi.is 5

6 Wedges Delayed action means deeper cuts if a stabilization target is to be reached. Long term mitigation Long term mitigation IPCC scenarios Mitigation Reduce emissions of greenhouse gasses Energy conservation Increase efficiency Reduce energy use Alternative energy sources Industrial processes Waste Agriculture Capture CO 2 to use as feedstock ThrosturTh@hi.is 6

7 Sequestration 1. Through photosynthesis Forests, soils, wetlands, oceans 2. Artificial sequestration Carbon capture Oceans Geological sequestration Chemical sequestration All sectors have the potential to contribute difference between sectors and regions Behavioral change is needed as well in addition to effective policies Changes in occupant behavior, cultural patterns and consumer choice in e.g. buildings, appliances etc. Reduction of car usage and efficient driving style, in relation to urban planning and availability of public transport Costs in 2050? Stabilization levels (ppm CO2 e.) Associated change in temp ; 3,2-4,0 C ; 2,8-3,2 C Change in net emissions (% to 2000 values) Changes in average annual GDP growth rates (%); total GDP decline in til +60 <0,05; -1 to 2-30 til +5 <0,1; slightly negative to ; 2,0-2,8 C -85 til -30 <0,12; <5,5 Kyoto Protocol The Kyoto Protocol is an agreement under which industrialized countries will reduce their collective emissions of greenhouse gases by 5.2% compared to the year Is a protocol to the UNFCCC signed in 1992 in Rio Became effective in 2005 The Goal "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. sets legally binding targets and timetables for cutting the greenhouse-gas emissions of industrialized countries ThrosturTh@hi.is 7

8 Principles Annex 1 versus Non-annex 1 countries Annex 1 countries responsible to reduce net emissions, and to submit GHG inventories Non-annex countries can participate via CDM (Clean Development Mechanism) Any Annex I country that fails will have to submit to 1.3 emission allowances in a second commitment period for every ton of greenhouse gas emissions they exceed their cap in the first commitment period (i.e., ) Principles Flexibility Joint Implementation (JI) Emissions permit trading (cap and trade) Clean development mechanism (CDM) Sequestration allowed Carbon Accounting National greenhouse gas inventories submitted annually to the Climate Change secretariat. The GHG data tables contain estimates for: CO 2 - Carbon dioxide CH 4 - Methane N 2 O - Nitrous oxide PFCs - Perfluorocarbons HFCs - Hydrofluorocarbons SF 6 - Sulphur hexafluoride Individual Commitments Iceland allowed increase emissions by 10% Plus the Icelandic exception. Extra 1600 tons of carbon per year allowed from countries that contribute less than 0,05% of total Annex 1 emissions Only for new heavy industry and that increases emissions more than 5% Commitments ESB: -8% Þýskaland, Danmörk: -21% Bretland: -12,5% Ítalía: -6,5% Frakkland, Finnland: 0% Svíþjóð: +4% Írland: +13% Spánn: +15% Grikkland: +25% Portúgal: +27% Sviss, A-Evrópuríki: -8% Bandaríkin: -7% Japan, Kanada, Pólland: -6% Rússland, Úkraína, Nýja- Sjáland: 0% Noregur: +1% Ástralía: +8% Ísland: +10% Individual Commitments Note: Differing commitments Differing base years between pollutants Differing base years between countries ThrosturTh@hi.is 8

9 Implementation Mechanisms Annex 1 Countries vs. others Went into force when 55% of emissions from Annex 1 countries accounted for and 55 countries had ratified US accounts for 36.4% of emissions Australia accounts for 2.1%(Now party) Active Feb with Russia ratifying Mechanisms As of 2008, a total of 173 countries and other governmental entities have ratified the agreement (representing over 63% of emissions from Annex I countries) How to reach Kyoto goals? Mitigation Reduce emissions Sequester carbon Post-Kyoto negotiations ongoing ThrosturTh@hi.is 9