California sardine stocks famously crashed in John Steinbeck’s “Cannery Row.” New research, building on the pioneering work of Soutar and Isaacs in the late 1960’s and others, shows in greater detail that such forage fish stocks have undergone boom-bust cycles for centuries, with at least three species off the U.S. West Coast repeatedly experiencing steep population increases followed by declines long before commercial fishing began.

Natural population fluctuations in Pacific sardine, northern anchovy and Pacific hake off California have been so common that the species were in collapsed condition 29 to 40 percent of the time over the 500-year period from A.D. 1000 to 1500, according to the study published today in Geophysical Research Letters. Using a long time series of fish scales deposited in low-oxygen offshore sedimentary environments off southern California, the authors from NOAA Fisheries and the University of Michigan described such collapses as “an intrinsic property of some forage fish populations that should be expected, just as droughts are expected in an arid climate.” 

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A team of University of Colorado Boulder engineers has developed a scalable manufactured metamaterial — an engineered material with extraordinary properties not found in nature — to act as a kind of air conditioning system for structures. It has the ability to cool objects even under direct sunlight with zero energy and water consumption.

When applied to a surface, the metamaterial film cools the object underneath by efficiently reflecting incoming solar energy back into space while simultaneously allowing the surface to shed its own heat in the form of infrared thermal radiation.

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The ongoing global change causes rising ocean temperatures and changes the ocean circulation. Therefore less oxygen is dissolved in surface waters and less oxygen is transported into the deep sea. This reduction of oceanic oxygen supply has major consequences for the organisms in the ocean. In the international journal Nature, oceanographers of GEOMAR Helmholtz Centre for Ocean Research Kiel have now published the most comprehensive analysis on oxygen loss in the world's oceans and their cause so far.

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Cracks in the Greenland Ice Sheet let one of its aquifers drain to the ocean, new NASA research finds. The aquifers, discovered only recently, are unusual in that they trap large amounts of liquid water within the ice sheet. Until now, scientists did not know what happened to the water stored away in this reservoir -- the discovery will help fine tune computer models of Greenland’s contribution to sea level rise.

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For decades, among the most enduring questions for ecologists have been: "Why do species live where they do? And what are the factors that keep them there?" A Princeton University-based study featured on the February cover of the journal Ecology could prove significant in answering that question, particularly for animals in the world's temperate mountain areas.

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