Lecture #4 Section 15.4 Part II Global Warming is Happening & Section 15.5 Kyoto Protocol

Evidence of Climate Change is Overwhelming “As best as can be determined, the world is now warmer than it has been at any point in the last two millennia, and, if current trends continue, by the end of the century it will likely be hotter than at any point in the last two million years.” American Geophysical Union

Evidence of Climate Change is Overwhelming Ave. global temperature climbed 0.6°C (1°F) in last century. 19 of 20 warmest years in the past 150 yrs have occurred since 1980. Hottest year since temperature records were begun was 2005; 2007 is expected to surpass it. Poles are warming fastest (4°C, 7°F over past 50 years). Permafrost is melting in Alaska and Canada and houses, pipelines and trees are being toppled.

Evidence of Climate Change is Overwhelming Arctic Sea ice is half as thick as it was 30 years ago, and the ocean area covered by ice has decreased by 1 million sq. km. in 30 yr. Polar bears are dying. Antarctic ice shelves are disappearing. Penguins declined 50% in last 50 yrs. Glaciers are melting all over the world. Sea level has risen 6 to 8 inches in last century.

Evidence of Climate Change is Overwhelming Oceans have been absorbing some of the extra CO2 but that is acidifying the ocean and damaging coral. Growing seasons are lengthening in Northern hemisphere. Some animals are breeding earlier or extending their range. Others are disappearing. Droughts are more frequent and widespread and storms more severe.

Global Warming will be Expensive At present, reducing greenhouse gas emissions would cost 1% of world GDP according to Stern report. (IPCC report says less than that.) If we delay, it could cost as much as 20% of world GDP. Energy production will need to be 80% decarbonized by 2050 to stabilize climate. Ethical issue Poor will suffer the most; at least 200 million people will become refugees of flood and drought.

Steps For Combating Climate Change Emissions trading markets already exist Technology sharing Reducing deforestation Helping poorer countries adapt to climate change Tropical areas will not change as much as middle and high latitudes. If both Greenland and Antarctica melt, 1/3 of Earth’s population will be displaced. - South Pacific island nation of Tuvalu already abandoned due to climate change

Combating Climate Change Insurance companies have $2 trillion in insured properties along U.S. coastlines at risk from flooding or severe storms. Infectious diseases will increase as insects that spread them are able to move to places where they could not live before. West Nile, malaria, and dengue fever have appeared in North America. Melting of permafrost may release stores of methane hydrate. Uncertainty about whether that would increase warming or cooling.

Predicted Warming for 2090-2099

International Climate Negotiations Kyoto Protocol (1997) 160 nations agreed to roll back carbon dioxide, methane, and nitrous oxide emissions about 5% below 1990 levels by 2012. Sets different limits for different countries, depending on prior output Developing countries exempted 126 countries have ratified the Protocol. U.S. took a leading role in the 1990s, but Bush declined to honor U.S. commitments.

Kyoto Protocol Bush claimed reducing carbon emissions would be too costly for the U.S. But in 2007, the CEOs of the 10 largest business conglomerates in the U.S. called for legislation to reduce greenhouse gases. A single national standard would be better for business than a patchwork of state and local rules. Companies engaged in international business will have to modify their products anyway to compete abroad.

Controlling Greenhouse Emissions Reducing carbon dioxide levels Renewable energy sources Double average fuel economy Switch to efficient lighting and appliances Wind turbines Biofuels Capture and store carbon dioxide Planting vegetation Injection into wells

Progress Made United Kingdom has rolled back its CO2 emissions to 1990 levels and is aiming for a 60% reduction by 2050. Germany has reduced CO2 by 10%. Denmark gets 20% of its electricity from windmills, and plans to increase that to 50%. China reduced its emissions 20% between 1997 and 2005. (At its present rate, U.S. will be 25% above 1990 emissions in 5 years. No progress.)

Carbon Management Capturing and storing carbon dioxide Build “trees” in which calcium hydroxide solution would absorb carbon dioxide Plant forests Fertilize the oceans with iron to permit phytoplankton growth, which would take up carbon dioxide Inject carbon dioxide underground or in ocean

Synthetic “Trees” that Capture Carbon Dioxide