In the 29 April issue of The Week, in the News section on page 4, a short piece says as follows:
Scientists have discovered a pristine coral reef in a previously unexplored part of the Galápagos Marine Reserve. The reef, which is about 1.2 miles long and lies 600 metres beneath the surface, was found by marine biologists using a submersible craft. They described it as "teeming" with life, including pink octopuses, crabs, sharks and rays. The discovery has raised hopes that some reefs will be able to withstand the impact of warmer and more acidic seas.
About the last sentence, I am wondering by how much, if at all, the temperature of the ocean 600 metres down has changed over say the past 100 years? The Pacific is big, and while surface temperatures might have risen, has the temperature at that depth changed by a measurable amount? If you know, let me know.
And the same for acidity. For example, the salinity of the Mediterranean is different to that of the Atlantic even though it is more than five million of years since the two were connected.