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On a PO W P, explain how the six determining factors of climate affect Pennsylvania. List each factor. Ex. The Gulf Stream only makes a difference in the fall for Pennsylvania weather when warm air produces rain instead of snow. Have you experienced global warming?. What is climate change?.
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On a POWP, explain how the six determining factors of climate affect Pennsylvania. List each factor.Ex. The Gulf Stream only makes a difference in the fall for Pennsylvania weather when warm air produces rain instead of snow.
What is climate change? • How do we study ancient climates? • What are the natural causes of climate change? • What changes may be caused by humans? • What are the effects of climate change? Test on Friday
The evidence • Fossils • Pollen • Tree rings • Ice cores • Changing sea levels
fossils • Palm trees in Northern Canada • Coal layers in Pennsylvania
pollen • Pollen from plants lands in lakes, gets covered by silt, can be dated by the layers, examined years later to see what plants grew many years before
Tree rings • Each tree ring is a reflection of what the conditions were like at the time of growth. • A thousand year old tree gives you a thousand years of records.
Ice cores • Layers of ice in Greenland capture air, dust, and pollen during each season.
What kind of evidence can be used to determine the climate of the past? Make a short list. 1 2 3 4 5 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
On a POYP • What are five different things that can be used to learn about what ancient climates were like? • Don’t forget to put your name on paper.
What are natural causes of climate change? • Earth’s position • Solar energy • Volcanic activity • Movement of continents http://images.google.com/imgres?imgurl=http://www.dan-dare.org/freefun/Images/CartoonsMoviesTV/IceAge2Wallpaper800.jpg&imgrefurl=http://www.dan-dare.org/freefun/games/CartoonsMoviesTV/IceAge/IceAge4.htm&usg=__bPDyKmEOloboNJEz3DAcs4hyRdg=&h=600&w=800&sz=72&hl=en&start=83&tbnid=H_4MdOj_oJVa4M:&tbnh=107&tbnw=143&prev=/images%3Fq%3Dice%2Bage%26gbv%3D2%26ndsp%3D20%26hl%3Den%26sa%3DN%26start%3D80
Earth’s position • The Earth wobbles as it orbits the sun. A wobble takes about 23,000 years. We are in a warm period between ice ages. The last glaciers here were about 10,000 years ago.
Solar energy • The sun goes through cycles.
Volcanic activity CO2 and ash
There is a high level of confidence that the global average temperature during the last few decades was warmer than any comparable period during the last 400 years. • Present evidence suggests that temperatures at many, but not all, individual locations were higher during the past 25 years than any period of comparable length since A.D. 900. However, uncertainties associated with this statement increase substantially backward in time. • Very little confidence can be assigned to estimates of hemisphere average or global average temperature prior to A.D. 900 due to limited data coverage and challenges in analyzing older data.
Warm water spreads from the west Pacific and the Indian Ocean to the east Pacific. It takes the rain with it, causing extensive drought in the western Pacific and rainfall in the normally dry eastern Pacific.
