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"Abstract The Phanerozoic fossil record of marine animal diversity covaries with the amount of marine sedimentary rock. The extent to which this covariation reflects a geologically controlled sampling bias remains unknown. We show that Phanerozoic records of seawater chemistry and continental flooding contain information on the diversity of marine animals that is independent of sedimentary rock quantity and sampling. Interrelationships among variables suggest long-term interactions among continental flooding, sulfur and carbon cycling, and macroevolution. Thus, mutual responses to interacting Earth systems, not sampling biases, explain much of the observed covariation between Phanerozoic patterns of sedimentation and fossil biodiversity. Linkages between biodiversity and environmental records likely reflect complex biotic responses to changing ocean redox conditions and long-term sea-level fluctuations driven by plate tectonics. "

Dr. Charles Miller Research Interests * Atmospheric Chemistry and Photochemistry * Molecular Spectroscopy * Carbon Cycle Science * Free Radical Structure/Reactivity Relationships

"Friday, December 14th, 2007 Coral in Crisis Bleached corals on coral reef on southern Great Barrier Reef in January 2002. Coral bleaching primarily affects reef building corals when conditions get too warm. Image © Science The world's coral reefs are in great danger, threatened by climate change and rising carbon dioxide levels. In an article published in the journal Science, researchers provide provide three different scenarios for the fate of reef-building corals worldwide as they face higher concentrations of atmospheric carbon dioxide and the related ocean acidification that slows coral calcification, the process needed for a reef to grow. Increasing CO2 levels have the potential to greatly shift the chemistry of ocean waters, threatening the existence of most coral species. "

"What are the impacts of ocean acidification on key benthic (seabed) ecosystems, communities, habitats, species and their life cycles? The average acidity (pH) of the world's oceans has been stable for the last 25 million years. However, the oceans are now absorbing so much man made CO2 from the atmosphere that measurable changes in seawater pH and carbonate chemistry can be seen. It is predicted that this could affect the basic biological functions of many marine organisms. This in turn could have implications for the survival of populations and communities, as well as the maintenance of biodiversity and ecosystem function. In the seas around the UK, the habitats that make up the seafloor, along with the animals associated with them, play a crucial role in maintaining a healthy and productive marine ecosystem. This is important considering 40% of the world's population lives within 100km of the coast and many of these people depend on coastal systems for food, economic prosperity and well-being. Given that coastal habitats also harbour incredibly high levels of biodiversity, any environmental change that affects these important ecosystems could have substantial environmental and economical impacts. During several recent international meetings scientific experts have concluded that new research is urgently needed. In particular we need long-term studies that determine: which organisms are likely to be tolerant to high CO2 and which are vulnerable; whether organisms will have time to adapt or acclimatise to this rapid environmental change; and how the interactions between individuals that determine ecosystem structure will be affected. This current lack of understanding is a major problem as ocean acidification is a rapidly evolving management issue and, with an insufficient knowledge base, policy makers and managers are struggling to formulate effective strategies to sustain and protect the marine environment in the face of ocean acidification."

How does climate change affect coral reefs? The warmer air and ocean surface temperatures brought on by climate change impact corals and alter coral reef communities by prompting coral bleaching events and altering ocean chemistry. These impacts affect corals and the many organisms that use coral reefs as habitat.

"As the amount of Carbon Dioxide continues to build up in the atmosphere it is also changing the chemistry of the ocean. Ocean surveys and modeling studies have revealed that the pH of the ocean is decreasing (which means the ocean is becoming more acidic) due to increasing concentrations of carbon dioxide. This changing oceanic environment will have severe implications for life in the ocean. COSEE NOW is pleased to present A plague in air and sea: Neutralizing the acid of progress a new audio slideshow that features Debora Inglesias-Rodriguez. In this scientist profile, Dr. Inglesias-Rodriguez, a Biological Oceanographer at the University of Southampton National Oceanography Centre, shares her story of how she grew up loving the ocean and became interested in science. She also explains how witnessing the effects of climate change has lead her to research how organisms like Sea Urchins are being affected by ocean acidification. Download A plague in air and sea: Neutralizing the acid of progress"

The term ocean acidification is used to describe the ongoing decrease in ocean pH caused by human CO2 emissions, such as the burning of fossil fuels. It is the little known consequence of living in a high CO2 world, dubbed at the 2009 United Nations Climate Change Conference (COP15) as the "evil twin of climate change". The oceans currently absorb approximately half of the CO2 produced by burning fossil fuel; put simply, climate change would be far worse if it were not for the oceans. However, there is a cost to the oceans - when CO2 dissolves in seawater it forms carbonic acid and as more CO2 is taken up by the oceans surface, the pH decreases, moving towards a less alkaline and therefore more acidic state. Already ocean pH has decreased by about 30% and if we continue emitting CO2 at the same rate by 2100 ocean acidity will increase by about 150%, a rate that has not been experienced for at least 400,000 years. Such a monumental alteration in basic ocean chemistry is likely to have wide implications for ocean life, especially for those organisms that require calcium carbonate to build shells or skeletons. Ocean acidification is a relatively new field of research, with most of the studies having been conducted over the last decade. While it is gaining some attention among policy makers, international leaders and the media, scientists find there is still a lack of understanding.

The Great Dissolving Ocean acidification is changing the chemistry of our seas Doug George

So, might you ask, what is the Anthropocene? First, the etymology. The Ancient Greek [anthropos] means "human being" while [kainos] means "new, current." The Anthropocene would thus be best defined as the new human-dominated period of the Earth's history. The term was proposed in 2000 by Paul J. Crutzen, Nobel Prize in 1995 for his work on atmospheric chemistry and his research on stratospheric ozone depletion (the so-called "hole"), and by Eugene F. Stoermer in a publication (p. 17) of the International Geosphere-Biosphere Programme. But the concept itself, the idea that human activity affects the Earth to the point where it can cross a new age, is not new and dates back to the late nineteenth century. Different terms were proposed over the decades, such as Anthropozoic (Stoppani, 1873), Noosphere (de Chardin, 1922; Vernadsky, 1936), Eremozoic (Wilson, 1992), and Anthrocene (Revkin, 1992). It seems that the success of the term chosen by Crutzen and Stoermer is due to the luck of having been made at the appropriate time, when humankind became more than ever aware of the extent of its impact on global environment. It should be noted that Edward O. Wilson (who suggested Eremozoic, "the age of loneliness") popularized the terms "biodiversity" and "biophilia." Technically, the Anthropocene is the most recent period of the Quaternary, succeding to the Holocene. The Quaternary is a period of the Earth's history characterized by numerous and cyclical glaciations, starting 2,588,000 years ago (2.588 Ma). The Quaternary is divided into three epochs: the Pleistocene, the Holocene, and now the Anthropocene.