Blue carbon is the term for carbon captured by the world's ocean and coastal ecosystems. You have probably heard that human activities emit (or give off) something called carbon dioxide, which contains atmospheric carbon. Our ocean and coasts provide a natural way of reducing the impact of greenhouse gases on our atmosphere, through sequestration (or taking in) of this carbon. Sea grasses, mangroves, and salt marshes along our coast "capture and hold" carbon, acting as something called a carbon sink. These coastal systems, though much smaller in size than the planet's forests, sequester this carbon at a much faster rate, and can continue to do so for millions of years.
The Impacts of carbon on the ocean include:
- Warming: Greenhouse gases trap energy from the sun, causing ocean water to warm. Warmer waters contribute to coral bleaching and sea level rise.
- Acidification: The ocean absorbs carbon dioxide, changing the pH of seawater and making it more acidic. This altered pH affects marine life, especially lobsters.
- Low oxygen levels: Warm water cannot hold as much oxygen as cold water creating dead spots for marine life.