OES Teacher WorkshopOES Teacher WorkshopUnit 3 – Session 3Unit 3 – Session 3

Climate and WeatherClimate and Weather

Climate and WeatherClimate and Weather

What is the difference?What is the difference? WEATHER = Meteorological conditions WEATHER = Meteorological conditions

(E.g., Air temperature, air pressure, (E.g., Air temperature, air pressure, humidity) at given place and time. humidity) at given place and time.

CLIMATE = Long term patterns and CLIMATE = Long term patterns and average of weather. Not just magnitude average of weather. Not just magnitude but also variability. but also variability.

ClimateClimate Average of conditions over several Average of conditions over several

decades.decades. http://www.esrl.noaa.gov/psd/cgi-http://www.esrl.noaa.gov/psd/cgi-

bin/data/usstation/state.pl?state=MDbin/data/usstation/state.pl?state=MD

ClimateClimate

Climate of SeattleClimate of Seattle• Rainy, relative moderate difference between Rainy, relative moderate difference between

winter and summerwinter and summer Climate of OhioClimate of Ohio

• Winters colder than BaltimoreWinters colder than Baltimore Climate of IndiaClimate 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

Baltimore WeatherBaltimore Weather

http://www.wunderground.com/http://www.wunderground.com/history/airport/KBWI/2015/7/6/history/airport/KBWI/2015/7/6/DailyHistory.html?DailyHistory.html?req_city=Baltimore-req_city=Baltimore-Washington+International&req_stateWashington+International&req_state=MD&req_statename=Maryland=MD&req_statename=Maryland

Current WeatherCurrent Weather

http://www.weather.com/maps/current

Climate vs. weather predictionClimate vs. weather prediction

Give an example of a practical Give an example of a practical climate prediction you make every climate prediction you make every year.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?

Why is it warmer in the summer Why is it warmer in the summer than it is in the winter?than it is in the winter?

A.A. Earth is closer to sun in summer.Earth is closer to sun in summer.

B.B. Sun is brighter in the summer.Sun is brighter in the summer.

C.C. Sun is higher in the sky in the Sun is higher in the sky in the summer.summer.

How does this explain seasons?How does this explain seasons?

Sun is higher in sky, Sun is higher in sky, sunlight is more sunlight is more concentrated in summer.concentrated in summer.

Sun is lower in sky, Sun is lower in sky, sunlight is more spread sunlight is more spread out in winter.out in winter.

Illustration- have kids Illustration- have kids mark shadows at noon in mark shadows at noon in winter- look at how length winter- look at how length changes.changes.

Why are the tropics warmer than Why are the tropics warmer than the poles?the poles?

Sun is always basically high in the Sun is always basically high in the sky in tropics.sky in tropics.

In polar regions sun dips below the In polar regions sun dips below the horizon for 6 months of the year, horizon for 6 months of the year, never gets very high.never gets very high.

Result of this…Result of this…

L

NorthSouth

Large-scale winds on earthLarge-scale winds on earth

Complicating this a little…Complicating this a little…

Pattern arises becausePattern arises because

Water has high heat capacity Water has high heat capacity (requires a lot of heat to raise (requires a lot of heat to raise temperature by a degree).temperature by a degree).

Soil has low heat capacity.Soil has low heat capacity. Land heats up more quickly than Land heats up more quickly than

water.water. Thermal lows develop over land in Thermal lows develop over land in

summer, over ocean in winter.summer, over ocean in winter.

Final complicationFinal 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.

SummarySummary

We can make seasonal climate predictions We can make seasonal climate predictions because…because…

Solar cycle repeats.Solar cycle repeats. Latitude stays constantsLatitude stays constants Distribution of continents, oceans is Distribution of continents, oceans is

constantconstant

But weather…..But weather….. Results from wiggles about the mean.. Results from wiggles about the mean..

Much more difficult to predict.Much more difficult to predict.