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Before we humans came along with our Industrial Revolution and our greenhouse gases, the earth was hurtling towards an intense ice age that could have covered much of the northern hemisphere with deep ice sheets as soon as 10,000 years from now, according to a tentative new study. But that’s no reason to thank our lucky stars for global warming, says study coauthor Thomas Crowley: “We’re creating a situation at least as dangerous, only going in the opposite direction” [Wired News].

Climate data shows that complex life evolved on a much warmer “hothouse earth,” and that the planet has been gradually cooling for the last 50 million years. Then, 2.5 million years ago, the climate entered a curious new phase: it started oscillating wildly, see-sawing between interglacial periods with conditions similar to today’s and ice ages during which the amount of permanent ice in the northern hemisphere expanded hugely. At the peaks of these transient ice ages, much of northern Europe, northern Asia and North America were covered in ice sheets [more than 2 miles] thick, and sea levels were [almost 400 feet] lower than today [New Scientist]. The new study argues that this period of oscillations was a transition to a stable, long-term ice age that would have made those previous ice ages look like mere cold snaps.

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The newly elected president of the Maldives, the island chain south of India, says his country must start saving up money to buy a new homeland, in case global warming causes sea levels to rise so much that the waves submerge the archipelago entirely. Says Maldivian President Mohamed Nasheed: “We can do nothing to stop climate change on our own and so we have to buy land elsewhere. It’s an insurance policy for the worst possible outcome…. We do not want to leave the Maldives, but we also do not want to be climate refugees living in tents for decades,” he said [The Guardian].

The Maldives are the lowest-lying nation on the planet: most of the islands are only a few feet above sea level, and the highest point, in the capital city of Malé, is about seven feet above sea level. But the white sandy beaches are a major tourist attraction bringing in billions of dollars every year…. Mr Nasheed’s plan is to create a “sovereign wealth fund” using tourism revenues to buy land so that future generations will have somewhere to rebuild their lives if they have to leave. He wants somewhere within the region, where the culture is similar - possibly India or Sri Lanka [BBC News]. However, Nasheed also mentioned Australia as a possibility, because of the vast swaths of unoccupied land on that continent.

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Using boat, tags, nets, and submarines, marine biologists from 82 nations have been canvassing the oceans for the first Census of Marine Life, an ambitious effort to get a rough tally of all the creatures in the world’s oceans. The 10-year project is expected to conclude in 2010, and researchers say the broad survey will help them observe changes to marine ecosystems. Says co-senior scientist Ron O’Dor: “We are moving into this period of global warming, which is resulting in the acidification of the oceans, melting of the polar ice cap. We can use the first census as a benchmark to see what happens in the oceans over the next decade or more” [BBC News].

Although the project still has two years to go, researchers have already made a host of startling discoveries, many of which will be discussed this week at the World Conference on Marine Biodiversity in Valencia, Spain. In one study, researchers conducted a genetic analysis of deep sea octopuses from around the world, and determined that most descended from a common ancestor species that still lives near Antarctica. Researchers believe that octopuses started migrating to new ocean basins more than 30 million years ago when, as Antarctica cooled and a large icesheet grew, nature created a “thermohaline expressway,” a northbound flow of tasty frigid water with high salt and oxygen content. Isolated in new habitat conditions, many different species evolved; some octopuses, for example, losing their defensive ink sacs — pointless at perpetually dark depths [LiveScience].

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Warmer winters in Norway seem to be causing a decline in lemming populations, according to a new study, and researchers say the decline of the rodent is having a cascading effect. Lemming predators, like foxes and owls, have been forced to hunt different prey in what researchers call a clear-cut example of how global warming can have a disruptive impact on entire ecosystems.

Lemming populations throughout Scandinavia tend to explode naturally every three to five years, causing huge numbers to go in search of food. Occasionally this leads the rodents to jump into water and swim to new pastures new—the origin of the myth that lemmings commit mass suicide. When lemmings boom, they’re hard to miss. Norwegians have had to use snowplows to clear the squashed rodents off the roads [National Geographic News]. But the study of lemming populations during the last four decades found no population explosions since 1994.

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A new analysis of Antarctic weather conditions has found that human-caused global warming is to blame for the changing climate at the south pole, according to a new study. In its landmark Fourth Assessment Report, the Intergovernmental Panel on Climate Change (IPCC) declared in 2007 that human influence on climate “has been detected in every continent except Antarctica” [Nature News]. Now, researchers have evidence that even that final frontier is feeling the heat from human activities.

In the study, published in Nature Geoscience [subscription required], researchers compared 100 years of Antarctic and Arctic climate records to the results of two sets of computerized climate models. Both sets factored in the effects of natural phenomena, such [as] volcanic eruptions and solar sunspot cycles, but only one set factored in the consequences of human activities that can affect climate, such as rising levels of the greenhouse gas carbon dioxide and fluctuations in the amount of ozone in the stratosphere. It was the models which included human factors that most closely matched the temperature profiles recorded at the poles. “For me, it can’t be more clear that human activity is responsible” [New Scientist], said study coauthor Alexey Karpechko.

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Two different studies separated by more than 1,700 miles hammer home the same point: evidence of global warming is everywhere. In Yellowstone National Park, researchers found that amphibian populations have declined dramatically over the past 15 years as some of their pond habitats have dried up and disappeared. Meanwhile, in Massachusetts’ Walden Pond, botanists discovered that more than a quarter of the plant species observed by Henry David Thoreau have disappeared since the author went to the woods to “live deliberately” in the 1850s.

The two studies, which both appear in the Proceedings of the National Academy of Sciences [subscription required], show that changes to the planet’s flora and fauna are already well underway. The Yellowstone study compared data from an amphibian survey done in 1992 and 1993 to data from a new survey conducted over the last three summers; researchers looked at the park’s “kettle” ponds, which are re-filled in spring by groundwater and snow melt running down from the hills [BBC News]. The researchers found that the number of permanently dry ponds had quadrupled, and even in the ponds that remained, amphibian populations had plummeted.

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New measurements of a rare but potent greenhouse gas finds levels to be four times higher than previously thought. Nitrogen trifluoride (NF₃), used mainly in the manufacture of flatscreen TVs and microcircuits, is 17,000 times more powerful at trapping heat than an equal mass of carbon dioxide. Although NF₃ is currently responsible for only 0.15 percent of human-induced global warming, the new analysis indicates that levels of the gas are rising “quasi-exponentially” [New Scientist].

Scientists at the Scripps Institution of Oceanography in La Jolla, California looked at air samples taken in California and in Australia. They found that over the past three decades, the atmospheric concentration of the gas has increased more than 20-fold, from 0.02 to 0.454 parts per trillion, with most emissions occurring in the Northern Hemisphere. The overall amount of the gas in the atmosphere, estimated in 2006 at less than 1,200 tonnes, was then actually 4,200 tonnes and has since risen to 5,400 tonnes, they report in Geophysical Research Letters [subscription required] [Nature News].

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Several rare varieties of staghorn coral have begun mating across species lines and are creating surprisingly robust hybrids, according to a new study; researchers believe the unusual step is an effort to adapt to changing ocean conditions and avoid extinction. The findings are an unexpected piece of promising news about coral reefs, which usually make the headlines for their potential fate as one of the first victims of global warming.

Coral reefs around the world are under pressure from pollution and gradually warming oceans, and researchers have worried that rare species are particularly vulnerable to extinction. But in the case of these staghorns, the new study shows that when faced with a shortage of mates of their own kind, these rare corals have cast a wider net and started cross-breeding with other coral species, producing hybrids. “It pushes the boundaries of our traditional understanding of species,” said a researcher, Zoe Richards. “They are being a little promiscuous” [Sydney Morning-Herald].

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As the turmoil continues in the world’s financial systems and countries brace for an economic downturn, many environmentalists and green tech entrepreneurs are posing the question: How will this crisis impact the young renewable energy sector?

Some worry that ambitious projects won’t be able to get the financing they need from troubled banks wary of lending money, while others note that oil prices have dropped fast based on predictions of lower demand. Advocates are concerned that if the prices for oil and gas keep falling, the incentive for utilities and consumers to buy expensive renewable energy will shrink. That is what happened in the 1980s when a decade of advances for alternative energy collapsed amid falling prices for conventional fuels [The New York Times].

In Europe, environmental ministers are meeting to finalize the European Union’s goals for cutting the greenhouse gas emissions that cause global warming, but new discord has broken out. Nations like Italy and Poland have begun to argue that emission cuts must be scaled back to avoid further hardship for industry during the hard economic times. Italian Prime Minister Silvio Berlusconi said: “Our businesses are in absolutely no position at the moment to absorb the costs of the regulations that have been proposed” [BBC News].

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In a new study, researchers looked at the role of cyclones in Earth’s carbon cycle. They found that cyclones (an umbrella term for hurricanes, typhoons, and tropical storms) can transfer terrestrial organic carbon, in the form of plants, soil, and fossils, to the bottom of the oceans and prevent it from entering the atmosphere. In just a few days a single typhoon can dump the same amount of carbon to the bottom of the ocean as an entire year of rain. The storms do this by ripping mud and decaying vegetation off the land, and flushing it down rivers in huge floods and out to sea [New Scientist].

The study, published in Nature Geoscience [subscription required], conducted on the LiWu river in Taiwan, focused on how cyclones sequester carbon rather than how much carbon they bury. Nevertheless, the researchers warn that the amount of carbon sequestered by cyclones is a pittance compared to the amount of carbon generated by human activity. “The current amount of carbon dioxide building up from manmade sources is about 100-1,000 times faster than this carbon (burial) from the interaction between the cyclones, erosion and forests,” said Robert Hilton of Cambridge University who was one of the authors. “In terms of the manmade carbon cycle this is not going to save us. But it illustrates that the earth has natural ways of dealing with carbon dioxide,” he said [Reuters].

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Global warming isn’t just a threat to polar bears in the rapidly warming Arctic, a new study says: Species in the tropics are beginning to feel the effects as well, and it will only get worse. Researchers surveyed more than 1,900 species of plants, insects, and fungi in a Costa Rica rainforest and came to the troubling conclusion that if world temperatures continue to rise as predicted over the next 50 years, half of those species will have to move to completely new territory to find an appropriate habitat.

The situation is complicated for tropical species, says lead researcher Robert Colwell; shifting north or south doesn’t bring significantly lower temperatures, so species will have to take up residence at higher altitudes to survive. In the absence of mountainsides to serve as a cool refuge, those plants and insects that cannot face higher temperatures may disappear as it would require migrations of hundreds or even thousands of miles to find a suitable cooler climate—crossing habitats utterly changed by human impacts. “For lowland tropical species whose geographical range lies far from mountains, for example in the middle of the Amazon,” Colwell says, “the prospect for extinction cannot be dismissed” [Scientific American].

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A warmer world will also be a sicklier place for both animals and humans, according to a new report from the Wildlife Conservation Society (WCS). Dubbed the “deadly dozen,” sicknesses such as Lyme disease, yellow fever, plague, and avian influenza, or bird flu, may skyrocket as global shifts in temperature and precipitation transform ecosystems. Babesia, cholera, Ebola, intestinal and external parasites, red tides, Rift Valley fever, sleeping sickness and tuberculosis round out the list [National Geographic News].

The report spells out how global warming is changing the ranges and habitats of animals that carry these infectious diseases, bringing the ticks that transmit Lyme disease and the mosquitoes that carry yellow fever and Rift Valley fever into contact with new human populations. “We’ve seen Lyme disease work its way up from the US into Canada, and West Nile fever as well,” said William Karesh, director of WCS’s global health programmes. “Basically what you have now are fewer frozen nights in this region, and that allows the ticks and mosquitoes that carry these diseases to survive further north” [BBC News].

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Alarming but preliminary reports of methane gas bubbling up from the Arctic Ocean have raised the specter of precipitous global warming in the minds of some climate scientists.

While aboard a research ship sailing off the coast of Siberia, scientists observed high levels of methane in the water, and then spotted several areas where the gas bubbles were fizzing up from the ocean floor, which contains vast amounts of frozen methane. That was enough to ring the alarm bells: Methane is about 20 times more powerful as a greenhouse gas than carbon dioxide and many scientists fear that its release could accelerate global warming in a giant positive feedback where more atmospheric methane causes higher temperatures, leading to further permafrost melting and the release of yet more methane [The Independent].

While the news seems disquieting, some researchers are expressing some skepticism about the findings, which haven’t yet been published in a peer-reviewed journal. The initial word from a heap of scientists who are focused on sub-sea methane deposits, including a group that videotaped big burps of methane bubbles off Santa Barbara, Calif., a few years ago, is a note of caution about overinterpreting the Arctic bubbling and high gas concentrations as something a) new or b) driven by human-caused global warming [The New York Times, Dot Earth blog].

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Many years after he revolutionized the field of physics, Albert Einstein took up a new task: inventing a better refrigerator. The 1930 appliance that he patented in partnership with a former student, Leo Szilard, had no moving parts and required no electricity, but was quickly forgotten as more efficient refrigeration technology was invented. Now, an electrical engineer has built a prototype of the forgotten Einstein fridge as part of a three-year project to develop more robust appliances that can be used in places without electricity [The Guardian].

Einstein and Szilard were reportedly spurred to inventive action by a news report of a Berlin family that died when toxic gas leaked from their refrigerator; the two physicists decided to create a system without moving parts to reduce the likelihood of accidents.

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Researchers have found that a one-year temperature spike can decrease the amount of carbon dioxide absorbed by a grassland ecosystem for up to two years. The four-year experiment, conducted at the Desert Research Institute in Nevada, adds a troubling new factor to calculations on how to best cope with global warming. Grasslands and their soils are considered a major sink for excess atmospheric carbon dioxide. Such natural carbon sponges, if they continue to thrive, could help alleviate the warming effects of manmade CO2 emissions [Science News].

In the experiment, which was described in the journal Nature [subscription required], researchers removed 12 large plots of grass with the underlying six feet of soil and microbes, each taken from the Oklahoma prairie in one piece. The plots were transported to the institute’s greenhouses, where the ecosystems were carefully controlled. Half the plots were exposed to normal fluctuations of temperature and rainfall, while the other half were subjected to one year where temperatures were consistently 7 degrees Fahrenheit hotter than usual.

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