Reports from the Australian government:
1) "Estimate the costs of undertaking a number management action based solutions sets designed to make
significant progress towards the 2025 reef targets (i.e. a 20 per cent reduction in anthropogenic end-of catchment
fine sediment loads for Mackay Whitsunday and Burnett Mary with a 50 per cent reduction in
the Fitzroy, Burdekin and Wet Tropics catchment by 2025; a 50 per cent reduction in anthropogenic end of-catchment
dissolved inorganic nitrogen (DIN) for Mackay Whitsunday and Burnett Mary catchments
and an 80 per cent reduction in the Burdekin and Wet Tropics catchments by 2025)"
and
"The greatest water quality risks to the Reef are:
excess nutrients (especially nitrogen from fertiliser),
fine sediments, and
pesticides."
http://web.archive.org/web/20160824045320/http://www.gbr.qld.gov.au/documents/costings-report.pdf (July 2016)
http://web.archive.org/web/20160824045320/http://www.gbr.qld.gov.au/documents/gbrwst-finalreport-es-2016.pdf (May 2016)
Compare this with Cuba.
http://www.pri.org/stories/2015-02-02/coral-coast-cuba-flourishing-rare-glimmer-hope-threatened-ecosystem
After the Soviets pulled out [in 1991], Cuba couldn't afford fertilizers and pesticides, so they were essentially forced into organic farming and that's had a beneficial effect on corals, Guggenheim explains.
The result has been far less nutrient pollution in the ocean waters surrounding Cuba. Nutrients in the water do the same thing in the ocean that they do on land: They fuel the growth of plants and algae and in the ocean those algae overgrow and ultimately kill coral reefs.
The other reason Cuba's coral reefs are so healthy is that they have fantastic environmental laws in place, Guggenheim says. Twenty-five percent of their waters are marine protected areas, compared to the worldwide average of about 1 percent. They are very good stewards of their environment, and I have faith in them to continue that, he adds.
Coral Reefs in the Caribbean have been hit particularly hard. Since 1970, about half of the coral cover in the region has disappeared, including almost 95 percent of the spectacular elkhorn coral. Rising ocean temperatures and pollution cause bleaching in coral, which is usually a death sentence. But even in areas around Cuba where researchers see bleaching, the coral tends to recover a sign of how healthy the ecosystem is.
It's not temperature or acidity killing the coral, it's pollution.
Corporations lie and say it's climate.