Transcript Slide 1
Earth’s Systems and Cycles Bellringer Define and give an example of the following: System Cycle Earth as a System A system is a part of the universe that can be studied separately. Scientists sometimes study individual parts of the Earth such as: How mountains form Classification of life forms How tornadoes form Today we understand that the all parts of the Earth are connected and interacting The best way to understand the Earth is not to study the parts in isolation but as one system Systems have Inputs and Outputs Pick one system you are familiar with and list the inputs and outputs for the system. Systems Have Feedback Loops http://politicalclimate.wordpress.com/2010/07/08/the-bad-kind-of-positive-feedback-climate-change/ Negative feedback – most common Think of a thermostat You set your thermostat for 70 degrees It senses the air temperature is below 70 so it signals the heater to turn on The heater warms the air in the room The thermostat senses the temperature is at 70 so it signals the heater to turn off This type of feedback helps to maintain equilibrium in a system Positive Feedback loop from NASA Positive Feedback In a positive feedback loop, it’s like your foot is stuck on the accelerator and you keep going faster! For more on systems and modeling, see Systems Theory and Modelinghttp://science.csumb. edu/esse21/index.php Image courtesy of Hugo Ahlenius, UNEP/GRID-Arendal Maps and Graphics Library. Closed vs. Open Systems Closed Systems Open Systems Matter does not enter or leave Matter can enter and leave Some energy is able to enter & leave Energy is able to enter and leave Earth is a Closed System Energy from the sun is absorbed by the Earth’s atmosphere and surface during the day Energy is lost back into space at night The matter on Earth is the same matter that was here when Earth formed. Matter changes form but the amount of matter remains the same . Mt Etna lava picture source: :http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=17479 How is a jar of sun tea like the Earth? Sun tea is made with tea bags and water in a closed jar that is left out in the sun. How is this similar to Earth as a closed system? Except…. What happens when a meteorite hits Earth? A tiny amount of Hydrogen atoms are lost to space. Overall, Earth is still considered a closed system. This means our resources must be conserved and protected. Earth’s system includes 4 spheres that interact The Atmosphere consists of the gases that surround the Earth The Geosphere (also called lithosphere) consist of the rocks, minerals, soils, ocean basins and Earth’s interior The Hydrosphere includes the water in oceans, rivers, groundwater, clouds, lakes, ice caps and glaciers The Cryosphere is sometimes used to describe frozen water in ice cap and glaicers The Biosphere includes all things living or coming from living things. Visualize Earth’s spheres: http://www.classzone.com/books/earth_science/terc/content/visualizat ions/es0102/es0102page01.cfm?chapter_no=visualization Earth’s Sphere’s Interact An erupting volcano releases lava, volcanic bombs (geosphere) and gases and ash into the air (atmosphere), the animals are suffocated (biosphere), plants burn up (biosphere), ash flows fill rivers (hydrosphere). http://volcano.und.edu/vwintl/vwintl.html More interaction examples Plants and animals take in oxygen from the atmosphere and release carbon dioxide. People remove plants, release chemicals into the air and water How does using cars show interactions between spheres? Car exhaust. © NMM London Cycles involve interactions between the spheres A cycle is a event or process that repeats over and over again. Examples: The water cycle The carbon cycle The nitrogen cycle A biogeochemical cycle moves nutrients between living and nonliving portions of the Earth http://www.windows.ucar.edu/tour/link=/earth/Water/co2_cycle.html&edu=mid