Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

Global Warming: The increasingly warmer than average temperature of the Planet over the 20th century.

is leading to global warming. An increase in the greenhouse effect is leading to global warming. What is the Greenhouse Effect?

Sunlight comes in and some reflects off the clouds back into space

Sunlight comes in and some is reflected off of the surface of the earth

Sunlight comes in and is absorbed as heat at the surface Sunlight comes in and is absorbed as heat at the surface. Some heat is then emitted from the earth and is released to space.

Sunlight comes in and is absorbed as heat at the surface Sunlight comes in and is absorbed as heat at the surface. Some heat is then emitted from the earth and is absorbed by the greenhouse gases, then re-emitted into the atmosphere and possibly back down to earth. The bouncing of Earths heat energy off the greenhouse gases in the atmosphere back towards the Earth’s surface is called the GREENHOUSE EFFECT.

Why is the temperature increasing? The natural greenhouse effect is being increased by extra greenhouse gases (GHG) trapping more heat on Earth Greenhouse Gases In natural levels are normal, and beneficial Trap energy in the atmosphere and make the Earth warm Have had a constant amount in the atmosphere for thousands of years Examples of Greenhouse gases Water Vapor (H2O) Carbon Dioxide (CO2) Methane (CH4) Ozone (O3) Nitrogen oxides (NOx) Chlorofluorocarbons (CFCs)

Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

Nobody debates that the temperature of the Earth is rising Nobody debates that the temperature of the Earth is rising. The last decade was the warmest of the century, and the last century was the warmest of the millennium.

How do we know the temperature of Earth is rising? We measure recent temperature changes directly with thermometers

How do we know the temperature of Earth is rising? We measure long term temperature changes indirectly through: Ice cores Coral remains Tree rings Historical records

How do we know the temperature of Earth is rising? We observe the effects of warmer temperatures: Melting of glaciers

Quelcaya Ice cap Peru Kilimanjaro East Africa

How do we know the temperature of Earth is rising? We observe the effects of warmer temperatures: Melting of Arctic and Antarctic ice shelves

Blue regions are now gone.

Jan 31 2002

17 Feb 2002

23 Feb 2002

05 March 2002

1979 Arctic ice coverage

2003 Arctic ice coverage

This graph depicts the decline in Arctic sea ice from 1978-2005 This graph depicts the decline in Arctic sea ice from 1978-2005. The trend from 1979 to 2005, now showing a decline of more than 8 percent per decade, is shown with a straight blue line. NSIDC

How do we know the temperature of Earth is rising? We observe the effects of warmer temperatures: Increase in ocean water levels Graph showing the predicted continued increase in sea level due to an increase in Earth’s temperature.

Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

No body debates whether global warming is happening. Some debate the cause. Although….

The VAST MAJORITY* of scientists believe that global warming is due to an increase in greenhouse gas emissions from human activity. * A very small minority think that global warming might be due to natural fluctuations of Earth’s temperature.

The concentration of two green house gases, carbon dioxide and methane, have risen greatly since pre-industrial times. Carbon dioxide: 33% rise Methane: 100% rise BW 5

The amount of CO2 in the atmosphere is definitely rising. We know because we can measure it directly.

It is also possible to determine the CO2 concentrations from the atmospheres of the past by examining CO2 trapped in glacier ice. These results show that the amount of atmospheric CO2 is strongly correlated to the amount of human industrial pollution.

In addition to CO2 levels, the concentration of the greenhouse gas METHANE has increased. The increase in atmospheric methane is thought to be due to and increase in: Cow flatulence (more demand for beef means there are many more cows which means there is much more cow farting. No joke.) Fossil fuel production Waste management Rice cultivation Wildfires

What causes the increase in greenhouse gases? Man made and natural causes Exhaust gases from cars Exhaust gases from factories Methane gas from animals Methane gas released when a tundra melts

Most scientists agree that pollution from human activity is contributing to the build up of greenhouse gasses in the atmosphere, leading to global warming. Look at the graphs. What do you think? Graphs are from the Intergovernmental Panel on Climate Change (IPCC), a consortium of several thousand independent scientists.

Which countries release the Greenhouse gas emissions by country. Which countries release the most greenhouse gases into the atmosphere?

If the pollution continues, mathematical calculations predict that the amount of greenhouse gas in the atmosphere will rise dramatically over the next 100 years.

Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

Several calculations predict that the temperature on Earth will rise significantly over the next 100 years if the amount of greenhouse gas emissions is not reduced.

Even a 1°C increase in global temperature will lead to: Melting glaciers Drowning of islands Coastal flooding Change in weather patterns Increase in fierce storms Difficulty growing food due to floods/droughts/salt water infiltrating fresh water supplies Diseases emerging in different regions of the globe. Increase in weather related mortality. In addition, changes in the natural environment support the evidence from temperature records: mountain glaciers the world over are receding; the Arctic ice pack has lost about 40% of its thickness over the past four decades; the global sea level is rising about three times faster over the past 100 years compared to the previous 3,000 years; and there are a growing number of studies that show plants and animals changing their range and behavior in response to shifts in climate.

Low-lying Bangladesh is prone to coastal flooding caused by storm surges, which have killed thousands of people in recent years. Experts say if the sea level goes up by 1 meter, Bangladesh will lose 17.5% of its land.

Predicted loss of coast land due to a 100m rise in ocean level on the west coast of the US.

What are effects of global warming LOCALLY?

Warmer, wetter winters, leading to… Reduced winter snow pack Reduced, warmer summer stream flow Increase winter flooding Changes timing of stream flows Rising sea levels Increased risk of extinction for marine life (as ocean temperatures rise, nutrient levels drop, and habitat changes)

The Main Impact: Less Snow April 1 Columbia Basin Snow Extent ~ 2045 Historical Average ~ 2025

Less snow leads to a decline of the summer water availability However, demand for water will increase because of warmer temperatures and an increasing population size.

Global Warming What is global warming? What evidence is there for global warming? What are the causes of global warming? What are the effects of global warming? What can you do to reduce global warming?

The way we live today will determine the temperature of the Earth in the future. Worst case: if high pollution emissions Best case: if low pollution emissions

Alternatives to Burning Fossil Fuels Renewable Energy Sources Solar Energies Wind Power Biomass Geothermal

Changes In Vehicle Systems Hybrid Fuel Cell Battery-Electric

But what can I do? Be energy – efficient!

Always remember to switch the bathroom light off after you go to the toilet.   Only fill the kettle with the amount of water you need. Don't leave your computer on after you're finished using it. If you feel too hot or too cold try adjusting your clothing first.