scts mod 9

• Weather


  Conditions of the atmosphere over a short period of time (e.g. minutes, hours, days, or even weeks)
• Climate


  Average weather over a long period of time over a certain place (usually ~30 yrs)
• Climate and weather are interrelated, likened to fraternal twins - related but not identical
• Climate change


  Change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable periods
• Climate variability


  Refers to variations in the mean state and other statistics (e.g. standard deviations, the occurrence of extremes) of the climate on all temporal and spatial scales beyond that of individual weather events
• Natural processes (internal and external forces) and anthropogenic (as a result of human activities) drive climate change
• Most of the observed increase in global average temperature since the mid-20th century is very likely due to observed increase in anthropogenic gas emissions
• Greenhouse gases (GHGs)


  Heat-absorbing gases found in the atmosphere that trap the sun's heat through the natural process - greenhouse effect
• Global warming


  Refers to the long-term heating of the Earth's climate system observed since the preindustrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping GHG levels in the Earth's atmosphere
• Global Warming Potential (GWP)

  A measure of the total energy that a gas absorbs over a given period (usually 100 years) relative to the emissions of 1 ton of CO2
• Sources of greenhouse gases

  • Burning fossil fuels (coal, natural gas, and oil), solid wastes, trees, and other biological materials
  • Certain chemical reactions (e.g., manufacture of cement)
  • Production and transport of coal, natural gas and oil
  • Livestock and other agricultural practices
  • Decay of organic wastes (e.g., municipal solid waste landfills)
  • Agricultural and industrial activities
  • Combustion of fossil fuels and solid waste
  • Treatment of wastewater
  • Industrial processes (e.g. hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride)
  • Substitutes for stratospheric ozone-depleting substances (e.g., chlorofluorocarbons, hydrochlorofluorocarbons, and halons)
• Major effects of global warming

  • Raising sea levels (melting of ice and glaciers)
  • Extreme weather events (powerful typhoons)
  • Exacerbating precipitation extremes (heatwaves, droughts, and floods)
  • Altering ecosystems and habitat (both terrestrial and aquatic)
  • Reduced food security
  • Pests and diseases
• Technology (traditional – present – futuristic), Earth-orbiting satellites, NASA, NOAA are used to monitor the changing climate and its effects
• Climate Change Mitigation


  Human intervention to reduce the sources or enhance the sinks of greenhouse gases
• Climate Change Adaptation


  The process of adjustment to actual or expected climate and its effects
• Mitigation Strategies


  • Replacing greenhouse gas-emitting fossil fuels like coal, oil, and natural gas with clean, renewable energies like solar, wind, and geothermal
  • Replacing traditional internal-combustion vehicles with electric options (ideally charged with renewable energy)
  • Retrofitting old buildings to make them more energy-efficient
  • Planting trees and preserving forests so they can absorb and store more carbon dioxide from the atmosphere
• Geoengineering


  Refers to the large-scale interventions to counter climate change by removing CO2 from the air or limiting the sunlight reaching the planet
• Adaptation Strategies


  • Building sea walls, elevating infrastructure, or retreating from low lying coastal areas altogether
  • Reducing and recycling water use due to drought
  • Using prescribed fires to prevent uncontrollable wildfires
  • Favoring drought-tolerant crops
• United Nations Framework Convention on Climate Change (UNFCCC) and Kyoto Protocol and Paris agreement are international agreements on climate change