Another year, another set of climate records. Here are the top ten signs you are living in a warming world, 2012 edition:

1. Hot enough for you? Though it’s only mid-December, it’s already clear that 2012 will be the hottest year on record for the contiguous United States. “The warm November virtually assures that 2012 will be the warmest year on record in the U.S.,” the National Oceanic and Atmospheric Administration recently observed. “The year-to-date period of January-November has been by far the warmest such period on record for the contiguous U.S.-a remarkable 1.0°F above the previous record. ” The Web site Climate Central put it this way: “There is a 99.99999999 percent chance that 2012 will be the hottest year ever recorded in the continental 48 states.”

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2. More hot air. Meanwhile, global carbon-dioxide emissions continue to climb. According to figures released earlier this month by the Global Carbon Project, run by the University of East Anglia and the Tyndall Center for Climate Change Research in the U.K., emissions hit a new record high in 2011. Global CO2 emissions from fossil-fuel burning and cement production increased by three per cent, to 34.7 billion metric tons. “These emissions were the highest in human history and 54% higher than in 1990,” the project reported.

3. The future of ice. On August 26, 2012, the extent of the Arctic sea ice shrunk to a record low, breaking the previous record, observed in the summer 2007. By the time the Arctic melt season ended, in September, ice extent was 1.27 million square miles below the 1979-2000 average. “The Arctic is the earth’s air-conditioner,” said Walt Meier, a research scientist at the snow and ice center “We’re losing that." (In The New Yorker this week, Keith Gessen writes about a new shipping route where ice used to be.)

4. The future of ice II. A team of experts from NASA and the European Space Agency reported that the Greenland and Antarctic ice sheets are now losing three times as much ice each year as they did in the nineteen-nineties. The acceleration was particularly dramatic in Greenland, which is now losing five times as much ice as it did in the mid-nineties. “Both ice sheets appear to be losing more ice now than twenty years ago, but the pace of ice loss from Greenland is extraordinary,” Erik Ivins, of NASA’s Jet Propulsion Laboratory, said.

5. Big trees down. A study by a trio of ecologists from Australia and the U.S. found that the world’s largest trees are dying at an alarming rate. The study blamed several factors for the decline, including land-clearing, man-made changes in fire regime, and rapid climate change. “Just as large-bodied animals such as elephants, tigers and cetaceans have declined drastically in many parts of the world, a growing body of evidence suggests that large old trees could be equally imperilled,” the three warned.

6. Six degrees of separation. A report by the global accounting firm PricewaterhouseCoopers warned that the possibility of limiting global warming to 2 degrees Celsius (3.6 degrees Fahrenheit)—a goal agreed to by the U.S. and virtually every other nation on earth—was rapidly slipping away. “Even doubling our current rate of decarbonisation, would still lead to emissions consistent with 6 degrees of warming by the end of the century,” the report warned. (That’s 6 degrees Celsius; in Fahrenheit the figure is 10.8 degrees.)

7. Water, water. Global sea levels are rising faster than predicted, a recent report on the journal Environmental Research Letters documented. The finding has significant implications for coastal cities, like New York.

8. And the water that’s gone. Water demand from the Colorado River is going to outstrip supply in the coming decades, a federal study released this month warns. The forecast is based on a combination of population growth and climate change, and has obvious implications for the forty million people who currently depend on the river.

9. Not-so-great lakes. Last month, the Great Lakes fell to their lowest level ever recorded for November, and the lakes are within inches of reaching an all-time record low. High temperatures and low precipitation have been blamed.

10. Extreme weather. According to a report by the reinsurance giant Munich RE, the number of weather-related “loss events” in North America has quintupled over the past three decades. The report attributed this trend to several factors, including climate change: “Climate change particularly affects formation of heat-waves, droughts, intense precipitation events, and in the long run most probably also tropical cyclone intensity.” The report was released just two weeks before Hurricane Sandy.

Photograph by Peter van Agtmael/Magnum.