The Great Barrier Reef UNESCO reports that Sediments and climate change pose the greatest threat to the reef

Unesco released a report on December 1st claiming that the biggest threats to the reef, climate change and chemicals/sediments, are "well managed." According to Michelle Innis of the New York Times, UNESCO is "severely understat[ing] the cost of doing so" as it ignores recent decisions made by the Australian government that could have future negative effects on the reef's health.

The Great Barrier Reef in 2013.

Scientists from the ARC Center of Excellence for Coral Reef Studies reported that the reef had suffered "the worst coral bleaching and die-off ever recorded" in the same week as UNESCO released their optimistic report and as the Australian government approved the opening of a new coal mine near the reef.

The effects of coral bleaching in the Great Barrier Reef.
"This year saw the most significant coral bleaching event ever recorded for the reef." – Ian Chubb
The Great Barrier Reef as seen from the air.

After several warnings about the Reef's condition, the Australian government stated that stopping nitrogen runoff from farms and preventing fine sediment from getting into the ocean would help the reef survive. Many of the measures in its Reef 2050 Plan to help the reef survive are in the process of implementation, but climate activists claim that the government is not committed enough as evidenced by its approval of a new coal mine.

"Virtually all of the relevant science indicates the Great Barrier Reef is in decline."

The water quality in the Reef is diminished by erosion from weather, mining, and deforestation that allows fine sediment to be swept into the ocean. Erosion is hastened by the removal of native plants that hold the soil together, and mining, agriculture, and deforestation all contribute to the ease with which rain and other runoff can pick sediments up.

The effect of sedimentation on coral.

The use of fertilizer and pesticides is also harming the health of the reef. Using too much of it causes the excess to be washed into the ocean in runoff from rain, degrading water quality and possibly poisoning the organisms (including coral polyps) that live in it.

A saltwater algal bloom in China.

If a large enough concentration of nitrates is reached in an area, algal blooms can occur that block out the sun and prevent the photosynthetic organisms underneath from replacing the oxygen that decomposers consume while breaking down algae, eventually suffocating the organisms that depend on oxygen, creating dead zones in the ocean where nothing can live.

The effects of ocean acidification in Curaçao.

Ocean acidification is caused by the accumulation of greenhouse gases (especially carbon dioxide) in the air. This leads to an increase in the amount of CO2 that is absorbed into the ocean, where it breaks down into carbonic acid, raising the pH level of the ocean. This makes it increasingly harder for polyps that build coral reefs and other shellfish, as they use calcium carbonate to construct their homes. The more acidic the water, the faster it eats away at their shells, eventually causing the organisms to die. This problem is not an easily fixable one and has widespread effects, making climate change the greatest threat to coral reefs around the world.

Bleached coral.

Made with Adobe Slate

Make your words and images move.

Get Slate

Report Abuse

If you feel that this video content violates the Adobe Terms of Use, you may report this content by filling out this quick form.

To report a Copyright Violation, please follow Section 17 in the Terms of Use.