Dec. 3, 2016

Slime and jellyfish

The oceans and climate change

I know I have written about water before, but I recently watched Years of Living Dangerously called Collapse of the Oceans on the National Geographic channel. It was quite alarming. The oceans are absorbing carbon from the excess carbon in the atmosphere which is the result of burning fossil fuels. When carbon mixes with water, a weak acid is formed called carbonic acid. In the past 200 years alone, ocean water has become 30 percent more acidic—faster than any known change in ocean chemistry in the last 50 million years. Many ocean organisms rely on a particular pH range for vital life functions such as shell formation and growth. Higher pH binds up carbonate ions and makes them less abundant—ions that corals, oysters, mussels, and many other shelled organisms need to build shells and skeletons. In recent years, shellfish industries such as oysters and scallops have been in fast decline. The oceans are also warming. Warmer temperatures also have a great effect on ocean chemistry and marine life. Warm water holds less oxygen. Fish will have difficulty getting enough oxygen and will not grow as large. Together, changes in pH and temperature are stressing marine life dramatically.

The program showed scientific experiments that involved growing coral in different tank environments, higher pH, higher temperature, both variables and also a control environment. The coral was negatively affected by pH and temperature separately, but was nearly non-viable when both were introduced into the environment. The coral bleached out then turned to slime. This is affecting coral all over the world. It was also reported that 80% of Caribbean coral reefs and 50% of the Great Barrier Reef are bleaching out at this very moment. The changing pH weakens the coral making them brittle and weak. Increases in extreme weather events, especially hurricanes and typhoons, more easily destroy these weaken reefs. Because of warming, lower pH and pollution, many scientists predict that coral reefs will be nearly gone by the middle of this century.

Coral reefs are among the most biodiverse ecosystems on the planet because they provide habitat for many species of marine organisms. Over 20% of ocean species are interrelated with coral reefs. Island nations depend on coral reefs for food, tourism and other sea-related economies. For example, in the Philippines, 65 million people depend on fish from the reefs for their daily sustenance. As a matter of fact, nearly 20% of the world’s population depends upon fish as their main source of protein. Many of these people live in undeveloped parts of the world. They contribute the least to the global carbon footprint, but have the most to lose from the effects of the rest of the world putting over 25 billion tons of carbon dioxide per year into the atmosphere and the oceans.

Some organisms fare well in less alkaline conditions. For example, jellyfish and algae that cause red tides. These toxic red tides kill all manner of marine life and are occurring in many areas of the world. Algal blooms caused by warmer waters, changing water chemistry and pollution are turning the oceans to slime. Slime and jellyfish. The program presented a bleak future as ocean systems collapse.