Climate change, dead zones examined : Study

A new study suggests nearly all ocean dead zones will increase in size by the end of the century as a result of climate change.

Dead zones occur in oceans, lakes and rivers when fertilizer runoff clogs waterways with nutrients, such as nitrogen and phosphorous.

That leads to an explosion of microbes that consumes oxygen and leaves the water depleted of oxygen, harming marine life.

Smithsonian Institution researchers found about two dozen different ways that climate change worsens the oxygen depletion in a study Monday in the journal Global Change Biology.

The researchers looked at 476 dead zones worldwide.

They used computer models to forecast that those dead zones will increase by about 4 degrees from the 1980s to the end of this century.

Agencies/Canadajournal