1. OES Teacher Workshop Unit 3 – Session 3 Climate and Weather

2. Climate and Weather What is the difference? What is the difference? WEATHER = Meteorological conditions (E.g., Air temperature, air pressure, humidity) at given place and time. WEATHER = Meteorological conditions (E.g., Air temperature, air pressure, humidity) at given place and time. CLIMATE = Long term patterns and average of weather. Not just magnitude but also variability. CLIMATE = Long term patterns and average of weather. Not just magnitude but also variability.

3. Climate Average of conditions over several decades. Average of conditions over several decades. http://www.esrl.noaa.gov/psd/cgi- bin/data/usstation/state.pl?state=MD http://www.esrl.noaa.gov/psd/cgi- bin/data/usstation/state.pl?state=MD http://www.esrl.noaa.gov/psd/cgi- bin/data/usstation/state.pl?state=MD http://www.esrl.noaa.gov/psd/cgi- bin/data/usstation/state.pl?state=MD

4. Climate Climate of Seattle Climate of Seattle Rainy, relative moderate difference between winter and summerRainy, relative moderate difference between winter and summer Climate of Ohio Climate of Ohio Winters colder than BaltimoreWinters colder than Baltimore Climate of India Climate of India Nov.-Mar, dryer, winds generally out of northNov.-Mar, dryer, winds generally out of north Jun-Sep. wet, winds generally out of southJun-Sep. wet, winds generally out of south

5. Baltimore Weather http://www.wunderground.com/histor y/airport/KBWI/2015/7/6/DailyHistor y.html?req_city=Baltimore- Washington+International&req_state =MD&req_statename=Maryland http://www.wunderground.com/histor y/airport/KBWI/2015/7/6/DailyHistor y.html?req_city=Baltimore- Washington+International&req_state =MD&req_statename=Maryland

6. Current Weather http://www.weather.com/maps/current

7. Climate vs. weather prediction Give an example of a practical climate prediction you make every year. Give an example of a practical climate prediction you make every year. Putting away winter coats in April.Putting away winter coats in April. Planting vegetables in May.Planting vegetables in May. Getting your furnace serviced in the fall.Getting your furnace serviced in the fall. How can we do this? How can we do this?

8. Why is it warmer in the summer than it is in the winter? A. Earth is closer to sun in summer. B. Sun is brighter in the summer. C. Sun is higher in the sky in the summer.

9. How does this explain seasons? Sun is higher in sky, sunlight is more concentrated in summer. Sun is higher in sky, sunlight is more concentrated in summer. Sun is lower in sky, sunlight is more spread out in winter. Sun is lower in sky, sunlight is more spread out in winter. Illustration- have kids mark shadows at noon in winter- look at how length changes. Illustration- have kids mark shadows at noon in winter- look at how length changes.

10. Why are the tropics warmer than the poles? Sun is always basically high in the sky in tropics. Sun is always basically high in the sky in tropics. In polar regions sun dips below the horizon for 6 months of the year, never gets very high. In polar regions sun dips below the horizon for 6 months of the year, never gets very high.

11. Result of this… L North South

12. Large-scale winds on earth

13. Complicating this a little…

14. Pattern arises because Water has high heat capacity (requires a lot of heat to raise temperature by a degree). Water has high heat capacity (requires a lot of heat to raise temperature by a degree). Soil has low heat capacity. Soil has low heat capacity. Land heats up more quickly than water. Land heats up more quickly than water. Thermal lows develop over land in summer, over ocean in winter. Thermal lows develop over land in summer, over ocean in winter.

15. Final complication https://www.youtube.com/watch?v=G600mcjVmjI Daily snapshots can show large north-south undulations in air masses. These instabilities of large-scale patterns produce storms and extreme weather.

16. Summary We can make seasonal climate predictions because… Solar cycle repeats. Solar cycle repeats. Latitude stays constants Latitude stays constants Distribution of continents, oceans is constant Distribution of continents, oceans is constant But weather….. Results from wiggles about the mean.. Much more difficult to predict. Results from wiggles about the mean.. Much more difficult to predict.