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Abstract Changes in the upwelling and degassing of carbon from the Southern Ocean form one of the leading hypotheses for the cause of glacial-interglacial changes in atmospheric carbon dioxide. We present a 25,000-year-long Southern Ocean radiocarbon record reconstructed from deep-sea corals, which shows radiocarbon-depleted waters during the glacial period and through the early deglaciation. This depletion and associated deep stratification disappeared by ~14.6 ka (thousand years ago), consistent with the transfer of carbon from the deep ocean to the surface ocean and atmosphere via a Southern Ocean ventilation event. Given this evidence for carbon exchange in the Southern Ocean, we show that existing deep-ocean radiocarbon records from the glacial period are sufficiently depleted to explain the ~190 per mil drop in atmospheric radiocarbon between ~17 and 14.5 ka.

"In some cases, cheaper types of fish were substituted for expensive species. In others, fish that consumers have been urged to avoid because stocks are depleted, putting the species or a fishery at risk, was identified as a type of fish that is not threatened. Although such mislabeling violates laws protecting consumers, it is hard to detect. Some of the findings present public health concerns. Thirteen types of fish, including tilapia and tilefish, were falsely identified as red snapper. Tilefish contains such high mercury levels that the federal Food and Drug Administration advises women who are pregnant or nursing and young children not to eat it."

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.

Isles of Abundance Britain has taken another step toward designating the world's largest marine reserve around the Chagos Islands, a group of 55 coral protrusions in the Indian Ocean. The government announced the end of a 4-month public comment period on 5 March and is expected to reach a final decision by May. The Chagos contain half of the Indian Ocean's remaining healthy reefs. The waters are said to be among the cleanest on Earth, allowing corals to grow in deep water less vulnerable to global warming. The islands are located in the equatorial "tuna belt," which hosts what a Royal Zoological Society of London report called one of the "most exploited, badly enforced fisheries in the world." A total ban on fishing in the 544,000-square-kilometer zone, an area the size of France, would make it an even larger protected area than the current record-holder, the 360,000-km2 Papahanaumokuakea Marine National Monument in the northwestern Hawaiian Islands. The Pew Environment Group has spearheaded a 3-year campaign for creation of a Chagos reserve. It would be "literally an island of abundance in a sea of depletion," says Pew's Jay Nelson. The islands are uninhabited except for the U.S. Navy base on Diego Garcia. Some 1500 Chagossians were deported to Mauritius in the 1970s for military security.