With increasing levels of carbon dioxide accumulating in the atmosphere and moving into marine systems, the world's oceans are becoming more acidic.
The oceans may be acidifying faster today than at anytime in the past 300 million years, scientists have found.
To address the concern for acidifying marine ecosystems, the National Science Foundation (NSF) recently awarded new grants totaling $12 million in its Ocean Acidification program.
The program is part of NSF's Science, Engineering and Education for Sustainability (SEES) investment.
The awards, the second round in this program, are supported by NSF's Directorates for Geosciences and Biological Sciences, and Office of Polar Programs.
From tropical oceans to icy seas, the projects will foster research on the nature, extent and effects of ocean acidification on marine environments and organisms in the past, present and future.
"With this round of awards, NSF has an increasingly diverse portfolio of research projects on ocean acidification," says David Garrison, program director in NSF's Directorate for Geosciences and chair of NSF's Ocean Acidification Working Group.
"These scientists will make major contributions to understanding this serious environmental threat," says Garrison.
"We look forward to building on this effort over the next few years, and expect that ocean acidification research will be a major contribution to SEES efforts at NSF."
Ocean acidification affects marine ecosystems, organisms' life histories, ocean food webs and biogeochemical cycling, scientists have discovered.
The researchers believe there is a need to understand the chemistry of ocean acidification and its interplay with marine biochemical and physiological processes before Earth's seas become inhospitable to life as it is known today.
Animal species from pteropods--delicate, butterfly-like planktonic drifters--to hard corals are affected by ocean acidification. So, too, are the unseen microbes that fuel ocean productivity and influence the chemical functioning of ocean waters.
As the oceans become more acidic, the balance of molecules needed for shell-bearing organisms to manufacture shells and skeletons is altered.
The physiology of many marine species, from microbes to fish, may be affected. A myriad of chemical reactions and cycles are influenced by the pH, or acidity, of the oceans.
"The Ocean Acidification awards address how organisms detect carbon dioxide and levels of acidity, and regulate these variables in their cells and body fluids," says William Zamer, program director in NSF's Directorate for Biological Sciences.
"These projects include studies of whether populations of animals have the genetic capacity to adapt to ocean acidification. The findings will yield new insights about how a future more acidic ocean will affect marine life."
Has ocean life faced similar challenges in our planet's past?
Earth system history informs our understanding of the effects of ocean acidification in the present and the future, says Garrison.
For a true comprehension of how acidification will change the oceans, he says, we must integrate paleoecology with marine chemistry, physics, ecology and an understanding of the past environmental conditions on Earth.
Overall, Ocean Acidification grantees will ask questions such as will regional differences in marine chemistry and physics increase acidification? Are there complex interactions, cascades and bottlenecks that will emerge as the oceans acidify, and what are their ecosystem implications? And if current trends continue, how far-reaching will the changes be?
NSF 2012 Ocean Acidification awardees, their institutions and projects are:
Jess Adkins, California Institute of Technology: Ocean acidification: Collaborative research: Measuring the kinetics of CaCO3 dissolution in seawater using novel isotope labeling, laboratory experiments, and in situ experiments
William Balch, Bigelow Laboratory for Ocean Sciences: Ocean acidification: Effects of ocean acidification on Emiliania huxleyi and Calanus finmarchicus; Insights into the oceanic alkalinity and biological carbon pumps
Joan Bernhard, Woods Hole Oceanographic Institution: Ocean acidification, hypoxia and warming: Experimental investigations into compounded effects of global change on benthic foraminifera
Robert Byrne, College of Marine Science, University of South Florida: Ocean acidification: Collaborative research: Investigation of seawater CO2 system thermodynamics under high pCO2 conditions
Anne Cohen, Woods Hole Oceanographic Institution: Toward predicting the impact of ocean acidification on net calcification by a broad range of coral reef ecosystems: Identifying patterns and underlying causes
Erik Cordes, Temple University: Ocean acidification: Physiological and genetic responses of the deep-water coral, Lophelia pertusa, to ongoing ocean acidification in the Gulf of Mexico
Robyn Hannigan, University of Massachusetts Boston: Ocean acidification: Effects on morphology and mineralogy in otoliths of larval reef fish
Donal Manahan, University of Southern California: Ocean acidification: Predicting "winners and losers" to ocean acidification--a physiological genomic study of genetically-determined variance during larval development
Figen Mekik, Grand Valley State University: Carbonate preservation in pelagic sediments: Developing a new aragonite preservation proxy
Bruce Menge, Oregon State University: Ocean acidification: Collaborative research: OMEGAS II - Linking ecological and organismal responses to the ocean acidification seascape in the California Current System
T. Aran Mooney, Woods Hole Oceanographic Institution: Ocean acidification: Examining impacts on squid paralarval development, behavior, and survival
M. Brady Olson, WWU Shannon Point Marine Lab: Collaborative research: Ocean acidification: Impacts on copepod populations mediated by changes in prey quality
Mak Saito, Woods Hole Oceanographic Institution: Ocean acidification: The influence of ocean acidification and rising temperature on phytoplankton proteome composition
Martin Tresguerres, UCSD Scripps Inst of Oceanography: Ocean acidification: Physiological mechanisms for CO2-sensing and related intracellular signaling pathways in corals
Jonathan Wynn, University of South Florida: Ocean acidification in the Canada Basin: Roles of sea ice
James Zachos, University of California-Santa Cruz: Ocean acidification: Collaborative research: Establishing the magnitude of sea-surface acidification during the Paleocene-Eocene Thermal Maximum