Greenhouse Gas Emissions Lecture 2 PDF

Greenhouse Gas Emissions (GHG emissions) The Carbon Cycle: Determines the amount of carbon dioxide in the atmosphere. Carbon dioxide is emitted into the atmosphere when we breathe, when plants and animals die and decompose, and when fires burn. The burning of fossil fuels intr...

Greenhouse Gas Emissions (GHG emissions) The Carbon Cycle: Determines the amount of carbon dioxide in the atmosphere. Carbon dioxide is emitted into the atmosphere when we breathe, when plants and animals die and decompose, and when fires burn. The burning of fossil fuels introduces new CO2 into the atmosphere Part of CO2 is absorbed by plants, wetlands, and the ocean. Global Warming: The rest of CO2 acts like a blanket around the earth ©Cambridge Business Publishers 1 2  Components of GHG Three largest greenhouse gases: carbon dioxide (CO2) methane (CH4 甲烷 ): nitrous oxide (N2O 一氧化二氮 ; 笑气 ): (gas leakage during extraction) (digestion of cattle and sheep) 3 Greenhouse Gas (GHG) 4  emissions (https://www.epa.gov/ghgemissions/overview- greenhouse-gases) Strategy Examples of How Emissions Can be Reduced Improving the insulation of buildings, using more Energy Efficiency fuel-efficient vehicles and more efficient electrical appliances. Reducing personal energy use by turning off lights Energy Conservation and electronics when not in use. Reducing distance traveled. Producing more energy from renewable sources and Fuel Switching using fuels with lower carbon contents. Capture CO2 from the stacks of a coal-fired power plant before it enters the atmosphere, Carbon Capture and Transport CO2 via pipeline, Sequestration (CCS) Inject CO2 deep underground at a suitable location, such as a nearby abandoned oil field. Changes in Uses of Land and Land Management Practices 5  2015 Paris Agreement on climate change Calls for making finance flows to reduce GHG emissions Goal: in this century, keep global temperature from increasing by less than 2C above pre-industrial levels even further to 1.5C Goal range: 1.5~2C above pre-industrial levels Effective in November 2016 Legally binding in forcing governments to take actions Kick off global drive in “climate finance” 6  2015 Paris Agreement goals 1.5C: net zero CO2 emissions by 2050, net zero GHG by 2065 7  Goals pledged by governments Not all countries need to reach net zero at the same time, depends on Responsibility for past GHG emissions Per-capita emissions Capacity to act Target years set by countries: US, EU, UK, Japan: committed to reach net zero by 2050 China and Saudi Arabia: by 2060 India: by 2070 8  Intermedium goal China: achieve carbon neutrality before 2060 Intermedium goal: peak emissions before 2030. Hong Kong: achieve carbon neutrality by 2050 Intermedium goal: reduce carbon intensity by 50% before 2035 compared with 2005 levels. 9  Hong Kong’s Climate Action Plan 2050 Announced in October 2021 10 GHG by country/region 11 Major sources of GHG worldwide 12