Climate Change
What Controls Climate and Weather in Earth's Atmosphere? Air/Water Energy (unequal) Earth’s Spin (this is responsible for the Coriolis Effect) Topography (mountains, canyons, ocean/shorelines, etc) The different ways that continents, oceans, and ice interact with solar energy.
Energy Remember the “ENERGY IN = ENERGY OUT” What is the ENERGY IN? Solar Radiation What is the ENERGY OUT? Reflection and long-wave radiation from Earth
The Greenhouse Effect Good or Bad? Major Green house gases H2O – water CO2 - Carbon Dioxide CH4 - Methane
Does Earth’s Climate Change?
What Could Cause the Earth’s Climate to Change? Changes in the Energy Changes in Earth’s Spin (this isn’t likely) Change the amount of energy absorbed or refelected. Changes in Topography
Changing Climate Changes in the Energy Can change because of the Milankovitch Cycles: periodic changes in the orbit and tilt of the Earth.
Changing Climate Changes in the Energy The Solar Cycle: cyclical changes in the amount of energy released from the sun.
Changing Climate Adding or Removing Greenhouse Gases Changes in the Energy Milankovitch Cycles The Solar Cycle Changes in the Greenhouse Effect Adding or Removing Greenhouse Gases
Changing Climate Change the amount of energy absorbed or reflected. Changes in Energy Changes in the Earth’s Spin (this isn’t likely) Change the amount of energy absorbed or reflected. Positive Feedback Loops: an event causes another event, which reinforces that initial event. Example: Ice-Albedo Feedback Changes in Topography Accomplished by plate tectonics
Is Climate Changing Today? Global average air temperature is increasing Global average ocean temperature is increasing Glaciers worldwide are retreating. Ecosystems are shifting. Sea level is rising.
Is the Climate Changing Today?
What is Causing Today’s Change Possible Causes Changes in Milankovitch Cycles …. Takes thousands of years The Solar Cycle …. Years to millions of years Changes in the Greenhouse Effect …. Years to million f years Plate Techtonics …. Millions of years
What is Causing Today’s Change Solar Cycle: Temperature change is probable not caused by the solar Cycle.
What’s Causing Today’s Change Changes in the Greenhouse Effect CO2 is increasing
Changing Greenhouse Effect Where are these gases coming from? Think about the Carbon Cycle Carbon is increasing in the atmosphere Carbon is increasing in the ocean Carbon is increasing in living plants (despite deforestation) So where is all of that carbon coming from? Increased combustion of fossil fuels
What Does it All Mean Most scientists now conclude that the changing climate on the Earth is, at least in large part, being caused by human activity.
Potential Impacts Disease: Ecosystems: Agriculture: Biodiversity: Diseases (mostly tropical) can spread to other areas Ecosystems: Floods, Droughts, Melting, Shifting ecosystems Agriculture: Reduced crop yields Biodiversity: Decrease Others: