1. What is this and how does it link to the topic?

2. Natural Causes of Climate Change L.O. To be able to describe the natural causes of climate change and their effects on the earth.

3. There are 4 main natural causes of climate change. These are: 1)Orbital Changes 2)Ocean Currents 3)Solar Output 4)Volcanic Activity In your books draw a table like the one on the board. You have been given a sheet with 16 statements on. Each statement gives detail about one of the 4 causes. Write the number next to the correct cause. Make sure you stick the sheet with the statements on in. You have 10 minutes.

4. 1) Large volumes of sulphur dioxide, water vapour and ash are thrown into the atmosphere. 2) Periodically, about every 11 years there is an increase in sunspot activity. 3) Without the circulation the Poles would be colder and the Tropics warmer. 4) The winter following the eruption of Krakatoa in 1883 was known as the Year without a Summer because of the cooling effect. 5) During the 17 th and 18 th centuries there was a lack of sunspot activity. It is suggested that this contributed to causing the Little Ice Age. 6) The first cycle operates over a 100,000 year period and over this time the Earth’s orbit changes from circular to elliptical. This means at times the Earth is closer to the Sun. 7) Sunspot activity has been at a minimum during the 20 th century, therefore energy has remained constant and this cannot be blamed for current global temperature trends. 8) This is the key source of energy on for the Earth. Without it life would not be able to survive. 9) The oceans are also one of the biggest stores of Carbon Dioxide, preventing it adding to the Greenhouse Effect. 10) These chemicals react with particles in the atmosphere to form aerosols. 11) The third cycle operates over a 21,000 year period and sees the Earth’s axis slightly change direction resulting in different hemispheres being closer to the Sun. 12) The second cycle operates over a 41,000 period and during this time the tilt of the Earth’s axis changes and can tilt us close to the Sun. 13) Currents move vast amounts of heat around the planet in the Thermohaline Circulation. 14) Sunspots are darker areas on the surface of the sun. When there is many sunspots there is an increase in solar energy output that results in warmer temperatures. 15) The astrophysicist Milankovitch first noticed changes in the Earth’s orbit and linked them to temperature changes. They are known as Milankovitch Cycles. There are 3 that can affect the Earth’s climate. 16) The aerosols reflect solar energy back into space and therefore have a cooling effect on the planet’s average temperature.

5. How do we know it’s not just humans that are to blame? There have been a number of climatic events in geological and recent history that could not have been caused due to global warming caused by humans. Two of these events are: 1)The extinction of Megafauna e.g. Woolly Mammoth 2)The Little Ice Age

6. 1) Extinction of Megafauna Significant changes are called geological climate events. The most recent change was the extinction of large animals called Megafauna at the end of the last Pleistocene Ice Age. Ice covering much of northern Europe and north America retreated towards the current Arctic Circle. Within a few centuries, megafauna were extinct and scientists think this was their inability to adapt to new conditions. Some argue it was also caused by the spread of humans into northern regions.

7. 2) The Little Ice Age Homework: On the A3 paper create a mind map of facts and ideas about the Little Ice Age. Use the base map on the board to start. You can include pictures, graphs as part of your mind map. Search the internet, use books to help you. There are some resources for you to use on: geography4schools.wikispaces.com