AP Environmental Science - Unit 9 Global Change Review

Overview

• Topics: Climate change, global warming, biodiversity issues.

Stratospheric Ozone

• Good Ozone (O3): Absorbs UV radiation, which can cause skin cancer and eye damage.
• Formation: UV radiation splits oxygen molecules (O2) into single O atoms, which combine with O2 to form O3.
• Ozone Depletion: Detected in 1985 as a hole over the Antarctic, caused by man-made chemicals (e.g., CFCs containing chlorine).

Chlorofluorocarbons (CFCs)

• Impact: Decompose to release chlorine, which breaks down ozone.
• Montreal Protocol: Effort to phase out CFCs and replace with alternatives like HFCs.

Greenhouse Effect and Greenhouse Gases

• Natural Process: Traps heat from the sun to keep Earth warm.
• Main Gases: Water vapor, carbon dioxide (CO2), methane, nitrous oxide, CFCs.
• Kyoto Protocol: Agreement to reduce greenhouse gases.
• Global Warming: Caused by excess greenhouse gases from fossil fuel combustion.

Carbon Dioxide and Global Warming

• CO2 Levels: Increase due to fossil fuel use and deforestation.
• Temperature Rise: Uneven global warming with significant shifts in northern latitudes.
• Feedback Loops:
  • Thawing permafrost releases methane.
  • Melting ice reduces albedo, increasing heat absorption.

Effects of Climate Change

• Habitat Loss: Melting ice affects species like polar bears.
• Species Relocation: Changes in biome distribution.
• Disease Spread: Increased due to climate changes.
• Sea Level Rise: Due to thermal expansion and melting glaciers.

Ocean Effects

• Warming: Affects species' metabolism and reproduction, causes coral bleaching.
• Ocean Acidification: CO2 forms carbonic acid, affecting shell-forming organisms.

Biodiversity Concerns (HIPPCO)

• Factors: Habitat destruction, invasive species, population growth, pollution, climate change, over-exploitation.
• Endangered Species Act: U.S. law protecting threatened species.
• CITES Agreement: International trade regulation to prevent species harm.

Protecting Biodiversity

• Legislation and Protection: Endangered Species Act, poaching laws.
• Habitat Corridors: Allow species movement.
• Reintroduction Programs: Example: Gray wolves in Yellowstone.
• Sustainable Land Use and Breeding Programs: Mitigate human impact.

Review Summary

• Importance of stratospheric ozone protection.
• Impact of human activities on global warming and biodiversity.
• Methods to mitigate effects and protect ecosystems.

[End of Review]