Are you ready for the quiz? Review yesterday’s notes in interactive notebook. Practice with objectives #1-4. Climate – on a geologic scale – WAAAAY back in the day! First, try this: Take the average of the following numbers: 100, 0 Take the average of 100,100,100,100,100,100,100,100,100,& 0 (that’s 9 sets of 100) How does having more data affect an average? Your GPA is a lot harder to change than a progress report grade. Use your graphreading skills to complete the worksheet Interactive notebook: New page Title: Historical Climate Date: April 14 Cut out Graph A and glue it onto the right side. Leave space below for notes Title the graph Historical Climate Change *Graph: Three important inferences Climate change is natural on Earth 100,000 year cycles between glacial maximum (ice age) and interglacial periods (maximum warmth) A change in -3oC can create an ice age A change of 1o is significant Global average temperature = 59oF Current CO2 concentration = 398ppm (changing your GPA is much harder than changing a progress report average in one class) Observations? *Milankovitch cycles Combination of these effects creates 100,000 year cycle of warming and cooling Earth’s orbit around the sun Ice core sampling We are changing the carbon cycle – burning ancient carbon (fossil fuels) moves C into the air. *Climate and civilization Human civilizations change when climate changes Farming relies on predictable weather Mayan civilization – collapses suddenly 950 CE (common era – used to be called AD) Leif Erikson – 950 CE sails to Greenland Black Death in Europe – famine 1315-1317 – needed to import grain from China Little Ice age – 1550-1850 Irish Potato Famine Dust Bowl – 1930’s drought+ poor farming practices Wrap it up! Which is surprising to climatologists – that the climate changes or the current rate of change? Has climate always been the same on Earth? What are Milankovitch cycles? How do we depend on predictable climate?