Could this be true?

[Mantasscareme]

Since starting this thread, I actually talked via e-mail with Ben McNeil, the gentleman mentioned in this article. He said while calcification rates will improve significantly, there will also be bleaching of certain species, so the net effect on coral reef health will likely still be negative. Sounds a bit different from the article.

 

[dk2943]

I would really like it to be true, but I am most skeptical.

 

[drbill]

A 2 degree Celsius increase in water temp?! Crap, I knew I should've bought a 3mm instead of a 5mm!

Kidding aside, an increase in water temp would be more favorable to algae than corals. And if there aren't enough herbivores to keep them in check, or if the wrong kind of algae flourishes (e.g. Caulerpa, Padina, the ones herbivores don't eat) then they will choke the reefs. Warmer water may be good for both corals and algae, but keep in mind that algae grow and propagate faster.

What's the basis for this? Warm water is what is causing the zooxanthellae (tiny algae) to leave the coral polyps and create bleaching.

Our warm temperatures this past summer in SoCal killed off much of the giant kelp (which is a cool water species). Of course it would favor other types.

 

[Mike Veitch]

Just one more quick (and maybe trivial) question to fuel discussion. All of the global warming articles cite a simulation that predicted a water temperature rise of 2 degrees Celsius (I know how us divers all hate metric). Does anyone know how much of a change in water temperature the 1998 El Nino caused in the places that were worst hit? I think this would help put it into perspective.

water temps in Palau rose from a typical 82-84 to a 87-90 and killed off almost all the hard coral in less than 2 months

 

[marku]

What's the basis for this? Warm water is what is causing the zooxanthellae (tiny algae) to leave the coral polyps and create bleaching.

Our warm temperatures this past summer in SoCal killed off much of the giant kelp (which is a cool water species). Of course it would favor other types.

Hi DrBill! What I meant was that an increase in water temp would be more beneficial for tropical macroalgae species than for corals. I myself don't see how warmer waters can benefit the reefs in the tropics. It might allow corals to thrive better in subtropical climates but it definitely won't be good for the reefs in the tropics (look at what ElNino did...).

Of course warm water won't be good for kelp! But here in the Philippines, macroalgae (e.g. Padina, Caulerpa, etc.) blooms usually coincide with the summer months when the water temps, especially in the intertidal areas, can reach >30degrees Celsius.