Reef-building corals (Order Scleractinia Class Anthozoa) form extensive skeletons of calcium
carbonate (limestone), depositing enough material over time to form vast reef structures that may be
easily seen from space. The majority of reef-building corals are hard (stony) scleractinian corals. Many
octocorals (especially soft corals in the family Alcyoniidae and the blue coral Heliopora) and some
hydrozoan corals (such as Millepora) also contribute to reef-building. Corals form the framework of
reef structures, while other organisms such as calcareous algae (especially red coralline algae) play a
key role in cementing and consolidating the reef framework. This chapter focuses on the vulnerability
of reef-building corals to climate change. The implications of climate change for macroalgae are
covered in chapter 7 and a broader treatment of reef processes is provided in chapter 17.This is Chapter 10 of Climate change and the Great Barrier Reef: a vulnerability assessment. The entire book can be found at http://hdl.handle.net/11017/13
