Fundamental to science is measurement. It is a way of objectively assessing something, anything, even the state of a coral reef, even of an individual coral. Historically coral growth rates were measured by coring the really old massive Porites.
Like tree rings in temperate forests, the massive old Porites can be cored to see the banding and from this it is possible to calculate coral calcification rates which are a measure of the growth rate of individual corals.
Peter Ridd has been asking for some quality assurance of so many of the measurements relating to Great Barrier Reef health, including coral growth rates. Key Australian institutions have responded by stonewalling, and in the case of James Cook University, actually sacking him. After two rounds in the federal courts his appeal against his dismissal is finally going to the High Court of Australia, with the next hearing probably in February 2021. While the lawyers are preoccupied with Peter’s rights, or otherwise, to academic freedom and freedom of speech, my concern is whether Peter is actually telling the truth when he says that the Great Barrier Reef is resilient and definitely not dying from coral bleaching, though there is a problem with the integrity of the science.
Most media reports, based on extensive aerial surveys by his one-time colleague Terry Hughes, conclude that the reef is variously 50% or 60% dead from coral bleaching as a direct consequence of global warming.
These media reports do not consider coral growth rates, but rather the area of coral that Professor Hughes has measured to be bleached, with an inference being that this will all die.
Terry Hughes and Peter Ridd can’t both be right.
How can they have come to such different conclusions regarding the health of the Great Barrier Reef? Is the reef really half dead, or not?
My working hypothesis is that Terry Hughes’ claims the reef is half dead, are not objective because there is a flaw with his particular survey method. This method is detailed in the technical literature, specifically his paper in Ecology published in 2018 entitled ‘Large-scale bleaching of corals on the Great Barrier Reef’.
Science is not a truth. It is a way of getting to the truth via some method or other that often involves measurement. Sometimes scientists get the method wrong, and so they come up with answers that are also wrong. Sometimes the wrong answer pleases because it is politically correct.
Could it be that in surveying by looking out the window of an aeroplane at such a high altitude (150 metres), and then ground truthing only with respect to a particular reef habitat-type known as the ‘reef crescent’, Professor Hughes has inadvertently recorded a wrong answer? Could he be avoiding, even in denial, when it comes to all the corals in the reef lagoon?
Marine scientists, and anyone with experience diving coral reefs, knows that there are distinct ecological zones at coral reefs. The reef crest, as the name suggests, is the highest part with corals in this habitat often exposed at low tides, sometimes rained-on, and during storms and cyclones this is the part of the reef that will be most likely smashed by big waves. Not surprisingly this habitat/area o