The Amazon Rain Forest and Climate Change

• Earth and Its Climate
  • Introduction
  • Our Atmosphere
  • Climate and Weather
  • The Greenhouse Effect
  • Greenhouse Gases
  • The Carbon Cycle
• Evidence of Climate Change
  • Man-made Change
  • Temperatures
  • Oceans
  • Snow and Ice
  • Rain, Drought, Extreme Weather
  • Ecology
• Future Projections
  • A Quick Look
  • Warming
  • Oceans
  • Ocean Ecosystems
  • Terrestrial Ecosystems
  • Health
  • Economics
• Brazil, the Amazon, and Climate Change
  • Brazil’s CO₂ Emissions
  • Tropical Forests and CO₂
  • Deforestation
  • Fires and Weather
  • Other Consequences
  • Carbon Sequestration and REDD
• International Agreements
  • UNFCCC: Convention on Climate Change
  • Kyoto Protocol
  • Emission Reductions

Oceans

Ships and buoys that dot the globe tell us the oceans are heating up too. The top 300 meters or so of the ocean have warmed by 0.3°C over the past 50 years. The deep sea, too, has warmed. A U.S. National Oceanic and Atmospheric Administration study that looked at the period from 1948 to 1998 found that every ocean warmed to at least 1,000 m.

And as air and oceans have warmed, the seas have risen. Global average sea level since 1993 has risen about 3.3 millimeters per year. All together, the IPCC estimates the oceans rose 10-25 centimeters in the 20th century as ice and snow melted and warmer water physically expanded.

In the last 10-20 years, sea level rise in southeastern South America has increased from 1 mm/yr to 2-3 mm/yr, and several ports in Brazil have recorded rises of 4 mm/yr. This swelling of the seas is expected to continue and will threaten coastal communities.

Sea levels aren’t the only way oceans change. The chemistry of seawater is changing too, as the seas absorb extra CO₂ from the air. This impairs the shell-building ability of ocean creatures like coral, plankton, and shellfish. If populations of these organisms plummet, the fish that eat them and the millions of people that eat the fish will suffer as well.