Global Warming and Climate Change

What is global warming? A gradual increase in the Earth’s temperatures as a result of rising levels of carbon dioxide and other greenhouse gases in the atmosphere.

How Global Warming Works Fossil fuels (coal, oil, natural gas) Carbon Dioxide (CO 2 )

Greenhouses can trap the sun’s rays because of their glass panels. This makes the inside of them warm. This is why in the winter they remain warm enough to be able to grow plants. The Greenhouse Effect

When the sun’s rays pierce onto the glass window of a greenhouse, the rays become weaker. Not all can pierce back through into the air. This causes the temperature inside the greenhouse to rise (get warmer). The Greenhouse Effect

When the sun’s rays pierce onto a window, they get “trapped.” The rays cannot all bounce back into the air. This causes heating of the area, which is known as the greenhouse effect. The Greenhouse Effect

The Sun’s energy passes through the car’s windshield. This energy (heat) is trapped inside the car and cannot pass back through the windshield, causing the inside of the car to warm up. Example of the Greenhouse Effect

This Greenhouse Effect on Earth A similar situation happens in the Earth’s atmosphere, but of course, no window is involved. The greenhouse effect on Earth helps us understand temperatures of the Earth, as well as the recent increase in the Earth’s temperatures, known as Global Warming. The Earth’s greenhouse effect involves the sun’s rays, the Earth’s atmosphere, and greenhouse gases which exist in the atmosphere. Let’s see...

The Greenhouse Effect on Earth There are a tiny number of gases (i.e. carbon dioxide, methane) found in the Earth’s atmosphere that when they sun’s rays are released, they absorb some of the heat before it can escape back into space. These are called greenhouse gases.

The Greenhouse Effect on Earth Greenhouse gases are essential for all life on Earth. They help keep some heat (warmth) in the Earth. Without greenhouse gases, temperature on Earth would always be about 30ºC colder. It would be a cold and lifeless planet like Mars!

The Greenhouse Effect on Earth We call them “Greenhouse Gases” because of the way they warm our Earth, very similar to how a greenhouse works as we saw in previous slides.

How does this contribute to Global Warming? Greenhouse gases have been increasing due to human activities that cause pollution (i.e. the burning of fossil fuels) in our atmosphere. The increase of greenhouse gases cause the Earth to get HOTTER. The atmosphere becomes “thicker” and more heat gets absorbed by greenhouse gases, because less can escape from the thicker atmosphere. This makes the Earth warmer. This is called Global Warming.

How does this contribute to Global Warming? Global Warming: Warming of the Earth’s temperatures due to a rise in greenhouse gases in the atmosphere.

Effects of Global Warming Rise in sea levels Chance in precipitation Forests, farmlands New parasites, new insect-borne diseases Droughts, flooding 8http:// 8

Assignment: Making Connections Textbook –page 462 #1-3

What’s the difference between “global warming” and “climate change”?

Difference GLOBAL WARMING is the increase of the Earth’s average surface temperature due to a build-up of greenhouse gases in the atmosphere. CLIMATE CHANGE is a broader term that refers to long-term changes in climate, including average temperature and precipitation.

Effects of Global Warming Increased Temperature Habitat Damage and Species Affected Changes in Water Supply Rising Sea Level

What’s the proof that global warming is taking place?

Portage Glacier Alaska Photos: NOAA Photo Collection and Gary Braasch – WorldViewOfGlobalWarming.org

Colorado River Arizona June 2002Dec 2003

Why is global warming happening?

Burning of Fossil Fuels Pollution from coal, natural gas, and oil

When did global warming start?

Global Atmospheric Concentration of CO 2

How is global warming measured?

Ice Core Data CO 2 Measurements Before Antarctica

CO 2 Atmospheric Measurements CO 2 Measurements Since 1958 – Mauna Loa, Hawaii

Temperature (Northern Hemisphere) CO 2 Concentrations 1000 Years of CO 2 and Global Warming Degree Celsius Increase Parts Per Million Year

Global Warming: Shifting Gears

2007 Goal: Reductions in CO 2 Per Year Billions of Metric Tons Carbon

2007 Reductions in CO 2 Per Year Gigaton Carbon Produce electricity efficiently Use electricity efficiently Vehicle efficiency Solar and Wind Power Biofuels Carbon capture and storage Billions of Metric Tons Carbon Our Goal

What’s being done now to reduce our emissions? Solar PowerWind PowerFuel-Efficiency

We can stop global warming!

What can you do to help solve the problem?

Simple Things To Do Turn off your computer or the TV when you’re not using it. Take shorter showers. Heating water uses energy. Keep rooms cool by closing the blinds, shades, or curtains. Turn off the lights when you leave a room. Use compact fluorescent bulbs.

Be Bulb Smart—Use CFLs Incandescent Compact Fluorescent 500 lbs. of coal What’s the difference? 1,430 lbs. CO 2 pollution avoided $30 saved

Simple Things To Do Dress lightly when it’s hot instead of turning up the air conditioning. Or use a fan. Dress warmly when it’s cold instead of turning up the heat. Offer to help your parents keep the air filters on your AC and furnace clean. Walk short distances instead of asking for a ride in the car. Plant a tree. Recycle.