In Australia, University of Queensland’s Professor Ove Hoegh-Guldberg has hit back at claims that his view on climate change’s impact on coral reefs is pessimistic.
A couple of days ago, two of his colleagues downplayed his comments that sea temperatures are likely to rise 2C over the next three decades, which would undoubtedly kill the Great Barrier Reef in Australia.
Today, Professor Hoegh-Guldberg posted a reply on his blog entitled “Great Barrier Reef could adapt to climate change, scientists say” – Facts, fallacies and fanciful thinking.
Hoegh-Guldberg begins by saying,
I must say I’m a little amazed that Andrew Baird has come out with such poorly supported statements. In fact, his opinions seem to depend almost entirely on his personal opinion! The argument that corals are able to magically “adapt” over one or two decades to climate change has come up many times over the years – always, with a complete dearth of evidence to support it.
After contacting Andrew Baird to see if he might know something Hoegh-Guldberg didn’t, Baird sent through a recently published article by Jeff Maynard and himself.
Hoegh-Guldberg clearly wasn’t impressed with the article, or its lack of evidence to support its conclusions. In response to the Maynard et al (2008) suggestion that coral reefs will be able to evolve and adapt with climate change, Hoegh-Guldberg commented,
Perhaps it is time for Baird and Maynard to propose a mechanism (with solid evidence) for how physiological traits such as thermal tolerance are able to evolve fast enough to keep rate with oceans that are warming and acidifying at rates which dwarf even the most rapid changes over the last several million years.
After dissecting the article piece by piece, Hoegh-Guldberg, acknowledes that coral reefs could potentially adapt to gradual climate change, but emphasizes that current global warming is occuring much faster than any other period in the last 420,000 years. He finishes with the following:
Overall, while the interest of Andrew Baird and his colleague Jeff Maynard are to be encouraged, one hopes that such loose and unsupported perspectives on such an important issue will be better thought out next time. No one doubts that evolution occurs on organisms like corals, and hence it adaptation if given time will occur, I think it is important that we realise how unusual the current situation is.
I together with 16 other leading scientific experts recently calculated the rates of change over the past 420,000 years and found that the current rates of changes in temperature and important aspects such as the carbonate ion concentration rose much as three orders of magnitude higher than even the most rapid rates of climate change over this period. Given the huge changes that did occur over this period in response to ice age and other global transitions, I think we need to be extremely careful in jumping to the conclusion that:
[to quote Andrew Baird] “adaptive qualities of coral reefs would mitigate the effects of climate change.”
Full text at Climate Shifts