Climate Change and Global Warming Notes
Climate Change and Global Warming
Definitions
- Weather: The state of the atmosphere at a specific place and time, described by precipitation, temperature, humidity, wind, and pressure.
- Climate: The long-term prevailing weather conditions in a particular area.
Key Definitions
- Climate Change: A change in climate measured over several decades or longer, potentially due to natural causes (e.g., volcanic eruption) or human causes (e.g., factory emissions).
- Adaptation: Actions taken to cope with the actual or anticipated impacts of climate change (e.g., cooling public transportation).
- Mitigation: Efforts to stop or slow climate change (e.g., buying an electric car).
- Resilience: The combined strategies of mitigation and adaptation that minimize the adverse effects of climate change.
Water Cycle
- Evaporation: The transformation of water from liquid to gas (water vapor) as it moves from land or bodies of water into the atmosphere.
- Transpiration: The release of water vapor from plants into the air.
- Condensation: The transformation of water vapor into liquid water droplets in the air, forming clouds and fog.
- Precipitation: Condensed water vapor that falls to the Earth’s surface, including rain, snow, hail, fog drip, and sleet.
- Freshwater Storage: Sources of freshwater like wetlands, lakes, ponds, large rivers, and storage in ice and snow.
- Snowmelt Runoff: Snow melts into streams.
- Ground Water Storage: Water present beneath the Earth’s surface in soil pore spaces and rock formations.
Facts About the Water Cycle
- Old groundwater is called fossil water.
- The sun drives the water cycle.
- The water cycle has no defined starting point.
Greenhouse Effect
- Short wave solar (radiant) energy enters the atmosphere from the sun.
- Some waves reflect off clouds and greenhouse gasses (GHGs) and return to space.
- Other solar energy waves reach the Earth’s surface.
- Upon hitting the Earth, these waves slow down and form longer heat (thermal) energy waves.
- These longer heat energy waves have difficulty escaping back into space through the GHGs, trapping heat and warming the planet.
- Increased GHGs from human activity and natural sources trap more heat, further warming the planet. GHGs act like the glass or plastic covering of a greenhouse, trapping heat.
Human Influence on the Greenhouse Effect
- Natural Greenhouse Effect allows some heat to escape into space.
- The Greenhouse Effect, intensified by humans, traps more heat due to increased greenhouse gases.
Greenhouse Gasses
- Carbon Dioxide Gas (CO2):
- Burning organic matter (wood, coal, gasoline) in the presence of oxygen.
- Deforestation.
- Respiration by living things.
- Methane Gas (CH4):
- Fossil fuel production, distribution, and use (26%).
- Natural release from plant decomposition, wetlands, and oceans (22%).
- Livestock farming (21%).
- Nitrous Oxide Gas (N2O):
- Natural release by soil bacteria and oceans.
- Agricultural sources (livestock waste and fertilizing crops).
- Water Vapor (H2O):
- Produced naturally by evaporation, sublimation, and transpiration.
Global Greenhouse Gas Emissions by Gas
- Carbon Dioxide (fossil fuel and industrial processes): 65%
- Carbon Dioxide (forestry and other land use): 11%
- Methane: 16%
- Nitrous Oxide: 6%
- F-gases: 2%
Facts About the Greenhouse Effect
- The right amount of greenhouse gasses is essential for preventing Earth from freezing and protecting from skin cancer.
- Greenhouse gasses come from both natural and man-made sources.
- N₂O is 300 times more efficient at trapping heat than an equal weight of CO₂.
Global Sea Surface Temperature
- Oceans cover about 70% of the Earth’s surface and absorb about 90% of the excess heat caused by the intensifying greenhouse effect.
- Increasing global sea surface temperature leads to:
- Rising sea levels due to water expansion as it warms and faster melting of sea ice.
- Threatened marine ecosystems (e.g., coral bleaching, low oxygen for fish).
- Increased water vapor over the oceans, leading to disruptive weather patterns (e.g., heavier rains and snows, drought).
- Threatened human livelihoods.
Concerns with a Changing Climate
- Economic concerns
- Environmental concerns
- Health concerns
Global Greenhouse Gas Emissions by Economic Sector
- Electricity and Heat Production: 25%
- Agriculture, Forestry, and Other Land Use: 24%
- Industry: 21%
- Transportation: 14%
- Other Energy: 10%
- Buildings: 6%
Ways to Mitigate Human Emissions of Greenhouse Gasses
- Reduce energy consumption (conserve energy).
- Electricity production is the #1 source of greenhouse gases (GHGs)
- Transportation is the 4th source of GHGs
- Reduce emissions from existing processes.
- Switch to renewable energy sources that don’t produce GHGs (e.g., solar panels).
Ways to Adapt to Climate Change in Agriculture and Natural Resources
- Increase shade and improve ventilation in barns for livestock.
- Breed crops that are drought tolerant or can thrive in more variable temperatures.
- Breed disease-resistant crop and livestock species.
- Change the crops grown in an area to ones that can thrive in changing climate conditions.
- Harvest and plant seeds from forest trees that are doing well in the changing climate conditions.
- Use only the water and fertilizers needed by the crop (precision agriculture).
- Use cultural practices like mulching to conserve water and improve soil temperatures.