East middle School Climate Change Unit 8 East middle School Climate Change

Why is earth a closed system? Closed system exchanges energy and not matter Open System exchanges matter and energy Earth is essentially closed because it exchanges energy from the sun but very small amounts of dust and rock Earth is Considered a CLOSED SYSTEM

How does energy change forms in the Earth System Wind to waves Radiation to heat Chemical to mechanical Burning fossil fuels

How does carbon move through Earth’s System It is part of the biogeochemical cycle. Gas CO2 Solid - Coal Biosphere as building blocks of life Absorbed by ocean

How can Carbon: BENEFIT HARM Improve soils Green house gas Powers our homes and Cars HARM Climate change Acidify the oceans Smog Too much can ruin soil

What is the greenhouse effect including comparison of the gases? Water vapor, Carbon Dioxide, Methane, Nitrous oxide, Ozone These gases help to regulate the global climate The trouble is if we get too much the balance is thrown off and the planet warms. Infrared radiation is absorbed by greenhouse gases, which in turn re-radiate much of the energy to the surface and lower atmosphere. The mechanism is named after the effect of solar radiation passing through glass and warming a greenhouse

Greenhouse Effect Annimation http://www.epa.gov/climatestudents/basics/today/greenhouse-effect.html

What are the natural mechanisms that result in climate change? Volcanic eruptions Changes in sunlight Meteorite impacts on Earth (Dinosaur extinction) Orbital changes Plate tectonics

What is the relationship between the emissions of carbon dioxide, and the average global temperature over the past 150 years? See the graph on the next page What relationships do you notice?

The Earth's climate has changed throughout history The Earth's climate has changed throughout history. Just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization. Most of these climate changes are attributed to very small variations in Earth’s orbit that change the amount of solar energy our planet receives.

Stunning NASA Visualization Reveals Secret Swirlings of Carbon Dioxide http://news.nationalgeographic.com/news/2014/11/141118-nasa-video-carbon-dioxide-global-warming-climate-environment/

What are the consequences of a warmer ocean? Increased evaporation Increased sea levels (see next page) Ocean acidification Less CO2 uptake Loss of land http://www.csc.noaa.gov/slr/viewer/#

Slow or stop the (ocean currents) thermohaline circulation Explain how the current melting of polar ice caps can impact the climate systems Slow or stop the (ocean currents) thermohaline circulation By less diffenence in water density More diluted ocean Warmer ocean less temperature difference. Example: No ocean currents would result in a colder climate for England

Describe geologic evidence that implies climates were significantly colder at times in the geologic record Milankovitch Theory –Changes in Earth’s orbit Amount of solar enery Organisms that lived in the cold oceans curled shell to left and organisms that lived in warmer oceans curled shells to right (pg 434) Volcanic dust blocking sunlight

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