Joan Kleypas

Coral reefs are appreciated by almost everyone for their beauty. For those who study them, their value becomes more apparent with every scientific discovery. Yet, coral reefs are changing before our eyes, and many feel that climate change will diminish this ecosystem to mere remnants of its former self. If we can't save coral reefs, then what will drive us to save other ecosystems? As we enter a climate-driven 'Noah's Ark' period to find ways to conserve ecosystems, I am inspired by the hope that, rather than using coral reef decline as a lesson in ecosystem science, our science will produce a model for successful ecosystem conservation.

Scientist III, Integrated Science Program

National Center for Atmospheric Research

Joanie Kleypas is a marine scientist who specializes on the effects of climate change on marine ecosystems. Her background is in the ecology and geology of coral reefs. For the last 10 years, Dr. Kleypas’ work has focused on two main aspects of rising atmospheric carbon dioxide concentration: global warming and ocean acidification.

Global warming has had profound impacts on coral reefs through a phenomenon called coral bleaching, the coral’s expulsion of the symbiotic algae that live within its tissues. While many stresses can cause coral bleaching, increasing sea surface temperatures have been clearly linked to the increased frequency and widespread nature of coral bleaching events that in some cases have destroyed entire coral reef communities. Dr. Kleypas’s work aims to improve our ability to predict which reefs are least vulnerable to future warming, and thus improve the success of conservation strategies. 

Dr. Kleypas is also involved in research on “ocean acidification,” which refers to the progressive, global reduction in seawater pH that results from the ocean’s increased uptake of atmospheric carbon dioxide. This large-scale environmental problem is gaining increasingly more attention as research reveals that ocean acidification can affect marine organisms, ecosystem functioning, and biogeochemical processes. Coral reef ecosystems are particularly threatened because ocean acidification is known to reduce the rates at which corals and other reef-building organisms build their skeletons. Dr. Kleypas takes a broad-brush approach to studying these effects on coral reefs. She works with marine chemists, coral physiologists, ecologists, and geologists to investigate how coral reef ecosystems, and indeed the reef structures themselves, will change over the course of this century.