climate change

• the energy for geological surface processes come from the sun radiates energy to the surface
• the energy used to drive internal processes comes from radioactive decay and heat leftover from the formation of the earth
• carbon, oxygen, nitrogen, phosphorus, sulfur, and water are cycled through the geosphere, atmosphere, hydrosphere, and bisophere
• weather systems driven by solar energy cause erosion that wears down rock into sediments
• plate tectonics causes volcanic activity which can create mountains and alter landscapes
• a tipping point is when counterbalancing feedbacks no longer work to maintain a stable state
• the earth's energy budget describes how energy arrives at and leaves eartyh
• the greenhouse effect helps keep more heat energy near earth's surface by absorbing and then re-emitting some of the energy reradiated from earths surface
• evapotranspiration is the evaporation of water from land and the transpiration of water from plant leaves
• evaporation increases humidity and cloud formation, decreasing further evaporation (negative feedback)
• warm air can hold more moisture
• albedo is the amount of incoming solar radiation that is reflected back into space
• cool air holds less moisture, so the moisture condenses and forms clouds and rain
• air moves from areas of high pressure to areas of low temperature
• humidity is the amount of water vapor held in the air
• relative humidity is the percentage of water vapor in the air compared to the maximum amount the air can hold at a given temperature
• weather: the state of the atmosphere at a particular place and time as regards heat, cloudiness, dryness, sunshine, wind, rain, etc.

  • measured over short-term
  • changes of the condition of the atmosphere at a certain place and time
  • precipitation and temperature
  • reported as a temporary forecast
  • local-occurs differently in certain regions
• climate: the weather conditions prevailing in an area in general or over a long period

  • measured as an average over a long period of time
  • six major climate zones: polar, temperate, arid, tropical, tundra, mediterranean
  • precipitation and temperature
  • reported as averages over a long period of time
  • occurs similarly over a large region
• greenhouse effect: the natural warming of earth's surface and lower atmosphere due to the trapping of infrared radiation by greenhouse gases

  • heat is absorbed and emitted by greenhouse gases
  • greenhouse gases are called greenhouse gases because they act as a greenhouse to absorb and trap heat from the sun
• greenhouse gases trap infrared energy from the sun and re-emit this energy as heat into the atmosphere

  1. solar radiation enters earth's atmosphere as heat energy
  2. earth's surface absorbs and reflects solar energy
  3. energy is re-radiated back into the atmosphere
  4. some energy is released back into space
  5. the remaining energy remains trapped in the atmosphere by greenhouse gases

  • this causes global temperatures to rise
• greenhouse gases in our atmosphere are important to life on earth

  • maintain a comfortable temperature on earth:

  1. too few gases = too cool for life
  2. too many gases = too warm for life

  • a small change in global temperature can upset earth's systems and cause changes to cliates
• carbon dioxide sources include fossil fuel combustion, deforestation, and cement production
• methane sources include fossil fuel production, agriculture, and landfills
• nitrous oxide sources include fertilizer application, fossil fuel and biomass combustion, industrial processes
• combustion: burning of fossil fuels and organic matter, such as forests, landfills, and biomass, releases heavy amounts of carbon dioxide and other greenhouse gases. burning fossil fuels for electricity, industry, and transportation also releases high amounts of greenhouse gases
• deforestation: forests take in store carbon dioxide during photosynthesis. deforestation causes less carbon dioxide to be taken out of the atmosphere
• agriculture: livestock, such as cows, release methane as byproduct of digestion. manure and fertilizers also release greenhouse gases
• industrial processes: refrigerants, foam-blowing agents, aerosol propellants, and fire suppressants release powerful greenhouse gases called HFC's
• earth has systems in place for keeping a balance of gases released through natural processes
• natural sources of greenhouse gases include:

  • wetland bacteria in anaerobic conditions
  • volcanic eruptions
  • wildfires
  • sediments and oceans
  • cell respiration
• carbon dioxide is the most abundant greenhouse gas and it stays in the atmosphere longer than most greenhouse gases
• human activities increase atmospheric CO2 levels primarily through the burning of fossil fuels for use in transportation, heating, and electricity
• the carbon cycle is the cycling of carbon molecules between oceans, air, organisms, and rocks
• factors that store or deduct the amount of carbon dioxide in the atmosphere are called carbon sinks

  • carbon sinks are important because the remove and/or store co2
  • examples: oceans, atmosphere, soil and sediments, forests, organisms
• excessive co2 in the ocean:

  • warms the ocean to fuel extreme storms and droughts
  • causes ocean acidification
  • acidic oceans cause coral bleaching, fish kills, and hinders marine organisms' abilities to create shells and skeletons
• global warming is the long-term heating of Earth's climate observed since the pre-industrial era (1850-1990) due to human activities
• albedo effect:

  • albedo is an expression of a surface's ability to reflect sunlight
  • light colored ice has a high albedo and reflects more light than dark-colored (low albedo) land and ocean surfaces
  • as warming sea ice melts, fewer light surfaces remain to reflect sunlight back into the atmosphere
  • rate of melting and global temperatures are further magnified in a positive feedback loop
• severe weather

  • one of the consequences of warming temperatures is an increase in the intensity and frequency of extreme weather
  • heat and drought: intensified drought in many areas; wildfires are more likely to occur in dryer and warmer conditions
  • storms and floods: higher frequency and strength of storms and floods; increased precipitation, destruction of ecosystems
  • snow and frigid weather: there is more moisture in a warmer atmosphere; when temperatures are below freezing, snowfall can break records; weakened jet stream allows frigid polar air to travel farther south
• more people = more greenhouse gas emissions
• carbon footprint: the total amount of carbon dioxide and other greenhouse gases that are released into the atmosphere by a product or service/personal energy consumption