ESC 110: Global Climate Change: Facts & Fiction Olympic rain forest isn't going away Tuesday, February 26, 2002 DAVID L. PETERSON RESEARCH SCIENTIST Olympic rain forest doomed by global warming, report fears Friday, February 8, 2002 By ROBERT McCLURE SEATTLE POST-INTELLIGENCER REPORTER Chapter 18 of text

GCC: Fact or Fiction From your text: One of “the two most immediate global environmental threats humans face is climate change caused by greenhouse gases. This is caused by the introduction of large quantities of human-produced gases into the atmosphere.” Are these statements true? Does everyone agree with them?

GCC: Givens Climate will change (because it has changed). Carbon dioxide levels are increasing in the atmosphere The greenhouse effect is real (and important). How will the climate change and how much will the climate change? Is the change natural or due to human activities? GCC: Questions

GCC: Greenhouse effect The greenhouse effect is caused by traces gases in the atmosphere (water vapor, carbon dioxide, methane, others) 1.4 o F -17 o C 59 o F 15 o C “Steady” 2

GCC: Changes in a greenhouse gas

Increasing Pattern Biological activity Human activity

GCC: Why is the greenhouse gas changing? Human activity?

GCC: Consequences of Increased CO 2 If CO 2 has increased, CO 2 is a greenhouse gas and Greenhouse gases warm the earth then The earth should be warmer! Is it? Yes But –Surface –Trend –Solar –Aerosols

GCC: Present Temperature Change to Historical

GCC: Climate Change: Predictions Know CO 2 will continue to increase Greenhouse effect should increase Therefore temperature should increase Four responses: A disaster The best news ever Do not know enough Natural cycles dominate MODEL

GCC: Implications on Plants Species responses Disturbance regimes

GCC: Implications on Plants: How do we know?

GCC: Let’s assume we need to do something, then what? Conservation Alternative energy sources Consumption Regulate carbon dioxide emissions (Kyoto Protocol) Carbon tax Use plants (trees) to take up or sequester the carbon.

GCC: Solutions with plants Could the earth’s biological systems accumulate sufficient CO 2 to balance emissions? Anthropogenic release Net uptake by terrestrial vegetation Net uptake by the oceans Gain by the atmosphere Giga ton = if the carbon was solid, 81 Safeco Fields and if the carbon was in the form of pure carbon dioxide, 392 Safeco Fields

GCC: Solutions with plants To balance the net gain of 4 Gt of carbon by the atmosphere through planting young forests, and, assuming an increase in production of 5 t ha -1 over the vegetation replaced, e.g., replacing an older, natural forest with a forest crop, requires over 10 9 hectares of young forest, ~14 times the size of Washington State. Balancing the CO 2 input from the US alone would require an area ~3 times Washington State ( ~1.2 times the size of California)

Global Climate Change: Where are we? Olympic rain forest doomed by global warming, report fears Friday, February 8, 2002 Human contribution Climate has changed Climate change has consequences Involved in a massive experiment You are the observers of this experiment. You will need to address when something should be done & how.