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We know climate change can affect us, but does climate change alter something as vast, deep and mysterious as our oceans? For years, scientists have studied the world's oceans by sending out ships and divers, deploying data-gathering buoys, and by taking aerial measurements from planes. But one of the better ways to understand oceans is to gain an even broader perspective - the view from space. NASA's Earth observing satellites do more than just take pictures of our planet. High-tech sensors gather data, including ocean surface temperature, surface winds, sea level, circulation, and even marine life. Information the satellites obtain help us understand the complex interactions driving the world's oceans today - and gain valuable insight into how the impacts of climate change on oceans might affect us on dry land.

Warming and Melting Mass loss from the ice sheets of Greenland and Antarctica account for a large fraction of global sea-level rise. Part of this loss is because of the effects of warmer air temperatures, and another because of the rising ocean temperatures to which they are being exposed. Joughin et al. (p. 1172) review how ocean-ice interactions are impacting ice sheets and discuss the possible ways that exposure of floating ice shelves and grounded ice margins are subject to the influences of warming ocean currents. Estimates of the mass balance of the ice sheets of Greenland and Antarctica have differed greatly-in some cases, not even agreeing about whether there is a net loss or a net gain-making it more difficult to project accurately future sea-level change. Shepherd et al. (p. 1183) combined data sets produced by satellite altimetry, interferometry, and gravimetry to construct a more robust ice-sheet mass balance for the period between 1992 and 2011. All major regions of the two ice sheets appear to be losing mass, except for East Antarctica. All told, mass loss from the polar ice sheets is contributing about 0.6 millimeters per year (roughly 20% of the total) to the current rate of global sea-level rise.

Experts Agree Global Warming Is Melting the World Rapidly Richard A. Kerr Forty-seven glaciologists have arrived at a community consensus over all the data on what the past century's warming has done to the great ice sheets: a current annual loss of 344 billion tons of glacial ice, accounting for 20% of current sea level rise. Greenland's share-about 263 billion tons-is roughly what most researchers expected, but Antarctica's represents the first agreement on a rate that had ranged from a far larger loss to an actual gain. The new analysis, published on page 1183 of this week's issue of Science, also makes it clear that losses from Greenland and West Antarctica have been accelerating, showing that some ice sheets are disconcertingly sensitive to warming.

Science 3 February 2012: Vol. 335 no. 6068 pp. 520-521 DOI: 10.1126/science.335.6068.520 News Focus Ecology Rebuilding Wetlands by Managing the Muddy Mississippi Carolyn Gramling Coastal managers and scientists have struggled to find ways to restore water flow through the wetlands of the Mississippi delta and bring back the sediment, supply of which has been cut in half by humanmade river channels, levees, and dams intended to control the river and save coastal communities from flooding. The U.S. Army Corps of Engineers opened the Morganza spillway during the 2011 Mississippi River floods to divert floodwaters, which offered a rare opportunity to conduct a large-scale natural experiment in real time. The floodwaters did carry enough sediment to help rebuild the wetlands, but that material didn't always stay where it could do the most good. However, researchers gained valuable insights-including ideas about how spillway design can help produce more targeted sediment deposits, and what volume of flow through the spillways might be required for effective wetland rebuilding.

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.

COSEE Network: The overall mission is "to spark and nurture collaborations among research scientists and educators to advance ocean discovery and make known the vital role of the ocean in our lives." Although each Center is funded individually, the Network of Centers has established its own set of goals: 1) Fostering the integration of ocean research into high-quality educational materials 2) Enabling ocean researchers to gain a better understanding of educational organizations and pedagogy 3) Enhancing educators' capacity to deliver high-quality educational programs in the ocean sciences 4) Promoting a deeper understanding of the ocean and its influence on each person's quality of life and our national prosperity