Rising Ocean Water Temperatures

Reader Contribution by Richard Hilderman and Ph.D.

Atlantic Ocean water temperature is rising rapidly!  In the first six month of 2012 the sea surface temperature from North Carolina to the Gulf of Maine was the hottest ever recorded according to NOAA’s Ecosystem Advisory. In Delaware and Chesapeake Bay some near shore water temperatures were more than 11 degrees Fahrenheit above the historical average at the surface and 9 degrees above the average at the bottom. Deeper off shore bottom water temperatures were 2 degrees above the average in the Eastern Gulf of Maine and more than 3.6 degrees above the average in the Western Gulf of Maine. Is the rising ocean temperature something we need to be concerned about?

1. Methane release from the ocean floor. Methane is stably stored on the ocean floor as long as it remains cold. Rising ocean temperatures are already releasing methane from the floor of the Arctic Ocean. Signs that this methane is being released hold serious implications for our planet’s atmosphere because methane is about 24 times more potent than carbon dioxide as a heat-trapping greenhouse gas. Some estimates suggest that there is more methane on the ocean floor than in all the Earth’s fossil fuel reservoirs.

2. Thermal expansion of ocean water. All solids, liquids and gases expand when they are heated. Thus rising water temperature will cause the sea level to rise and endanger the lives of over 100 million people who live close to the sea.

3. Coral reefs are a habitat for almost a quarter of all species living in the ocean. Coral reefs also protect coastal areas from storms and storm surges. Microalgae form a symbiotic relationship with the coral. The coral provide the microalgae with a protected environment along with carbon dioxide – used for photosynthesis – and other nutrients such as nitrate and phosphate. The algae photosynthesize returning oxygen for the coral and removing waste. As the ocean water temperature increases this symbiosis breaks down because the coral expels the microalgae, turn white – bleaching – and die. Between 1876 and 1979 there were only 3 bleaching events, but over 60 bleaching events were documented between 1979 and 1990. Since 1990 coral reefs on Australia’s Great Barrier Reef have declined by 14 percent and only 3 to 5 percent of the coral remains in the Florida Keys.

4. The warming ocean has changed the distribution of various fish. About half the 36 fish stocks studied in the Northwest Atlantic Ocean – many are commercially valuable species – have been shifting northwards for the past four decades and some have shifted themselves completely out of US waters.

What is it going to take for our government leaders to take the climate crisis seriously and convert to carbon neutral energy sources?