Environment: Air pollution can stunt coral reef growth

New study may help inform reef conservation effrot

dfgs

Bleached coral in the Caribbean. Photo courtesy NOAA.

By Summit Voice

SUMMIT COUNTY — Coral reefs are at risk from global warming, but regional aerosol emissions may also be a significant factor in how corals grow, according to a new study by scientists with the Smithsonian Tropical Research Institute.

The research linked airborne particles caused by volcanic activity and air pollution to episodes of slow coral-reef growth. The findings came as part of an effort to to better predict the effects of climate change and human disturbance on reefs.

The data came from several coral cores drilled in reefs near the Atlantic entrance of the Panama Canal formed by the coral species Siderastrea siderea between 1880 and 1989, whereas samples from the Turneffe atoll in Belize showed growth fluctuations in the coral species Montastrea faveolata from 1905 to 1998.

Particles from air pollution, primarily sulfate, reflect incoming sunlight and make clouds brighter reducing the amount of sunlight reaching the sea surface. Coral growth corresponded closely to sea surface temperatures and light levels. Growth fluctuations in the late 19th and early 20th centuries were largely driven by volcanic activity.

 

The influence of human aerosol emissions was more pronounced in coral cores from Belize, perhaps because Belize is closer to sources of industrial emissions. Fluctuations unexplained by the model, especially in the growth records from Panama, probably result from runoff from deforestation and from the construction of the Panama Canal waterway.

Like tree rings, long-lived coral skeletons preserve a record of coral growth. Previously, scientists linked coral-growth patterns in the Caribbean to a phenomenon called the Atlantic Multi-decadal Oscillation—fluctuations in sea-surface temperatures and incoming sunlight.

Particles from air pollution, primarily sulfate, reflect incoming sunlight and make clouds brighter reducing the amount of sunlight reaching the sea surface. Coral growth corresponded closely to sea surface temperatures and light levels. Growth fluctuations in the late 19th and early 20th centuries were largely driven by volcanic activity.

Researchers explain a dive in surface temperatures and coral growth in the 1960s by increased air pollution associated with post-World War II industrial expansion in North America and to a lesser extent in Central and South America.

The influence of human aerosol emissions was more pronounced in coral cores from Belize, perhaps because Belize is closer to sources of industrial emissions. Fluctuations unexplained by the model, especially in the growth records from Panama, probably result from runoff from deforestation and from the construction of the Panama Canal waterway.

 

About these ads

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

Follow

Get every new post delivered to your Inbox.

Join 6,972 other followers

%d bloggers like this: