Spring! Not.

Across the US, this winter has been unusually balmy, with precious little snow, or even rain, and with trees taking the warmth as a cue to send out new leaves in January. Temperature data support those impressions: in the first week of the year, temperatures were 40 degrees F higher than average in some parts of the Midwest, Discovery News reports, and snow cover is at 19 percent across the country, compared to an average of 50 percent at this time of year. In notoriously chilly Fargo, North Dakota, the January 4 high temperature of 55 broke the record for the warmest January day on record, and the country has seen close to no rain or snow in this first week of 2012, writes Wunderground meteorologist Jeff Masters. “It has been remarkable to look at the radar display day after day and see virtually no echoes,” he writes, referring to the radar echoes reflected back by storms. “It is very likely that this has been the driest first week of January in U.S. recorded history.”

Why this freaky weather? The answer is, basically, an extremely unusual jet stream over the last few months, Masters explains. The jet stream that defines weather in North America is controlled by the North Atlantic Oscillation and the Arctic Oscillation, climate patterns that reflect differences in sea-level pressure across certain stretches of the globe. And the pressure differences this year have been tremendous—for the North Atlantic Oscillation (NAO), this year saw the most extreme difference ever recorded in December, and the second most extreme for the Arctic Oscillation (AO).

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The Eastern Seaboard is warily watching the progress of Hurricane Irene, wondering what course the storm will take and just how ferocious it will be. Predicting the path of a hurricane still involves some guesswork—but thanks to rapidly improving computer models and data-gathering abilities, Tekla Perry reports in IEEE Spectrum, scientists are able to make more accurate forecasts farther in advance than they were even five or ten years ago. In fact, the predicted track of a hurricane over the next 48 hours today is as accurate as a prediction for the next 24 hours was 10 years ago—a day that can make a big difference for people deciding whether to evacuate and how to prepare before the storm. Boosts in computing power mean scientists can run more, faster, and more detailed simulations of the storm, and technologies like Dopper radar provide detailed data on wind speed, air pressure, and temperature as storms progress.

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One cannot look at a single storm, flood, or drought and say conclusively, “climate change caused that.” But what researchers are attempting to do lately is climate change risk assessment—figuring out how much more likely severe events may become as our world continues to warm up. Two new studies in Nature today try to do just that with heavy rains and flooding, saying definitively that warm temperatures make these events more likely.

More-localized weather extremes have been harder to attribute to climate change until now. “Climate models have improved a lot since ten years ago, when we basically couldn’t say anything about rainfall,” says Gabriele Hegerl, a climate researcher at the University of Edinburgh, UK. [Nature]

Hegerl and climate researcher Francis Zwiers were authors on study number one, a broad-based look at how much humans are contributing to intense precipitation events in the Northern Hemisphere. The simple physics of it makes sense: warmer air can hold more water. To show a link, however, the researchers pulled together a half-century of rainfall records, which they compared to the results of eight different climate models.

Richard Allan, a climate scientist at the University of Reading in England who was not part of the study, called the method employed by Zwiers “very rigorous.” He added, “There’s already been quite a bit of evidence showing that there has been an intensification of rainfall” events across the globe. But until now “there had not been a study that formally identified this human effect on precipitation extremes,” Zwiers said. “This paper provides specific scientific evidence that this is indeed the case.” [Washington Post]

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“Return to previous Arctic conditions is unlikely.” That’s the understated conclusion from this year’s Arctic Report Card, which found that air temperatures will continue rising and ice will continue melting in the Arctic as global warming continues to take its toll on the region. The annual report was prepared by 69 researchers in eight countries, and was issued by the U.S. National Oceanic and Atmospheric Administration.

What goes on in the Arctic doesn’t stay in the Arctic. The researchers note that conditions in the Arctic can affect global weather, and point to the huge snowstorms that hit the American northeast and mid-Atlantic states last winter as an example.

“Normally the cold air is bottled up in the Arctic,” said Jim Overland of the National Oceanic and Atmospheric Administration’s Pacific Marine Environmental Laboratory in Seattle. But last December and February, winds that normally blow west to east across the Arctic were instead bringing the colder air south to the Mid-Atlantic, he said. “As we lose more sea ice it’s a paradox that warming in the atmosphere can create more of these winter storms,” Overland said at a news briefing. [Washington Post]

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The insurance industry’s weather simulator is more awesome than your weather simulator. It can hold nine houses, create hurricane-force conditions on its interior via 750,000-gallon tanks of water, and it just opened.

The Institute Business & Home Safety, an organization backed by the insurance industry, built the $40 million hangar of destruction in South Carolina.

With an update next year, “we’ll shoot hail down from the rafters of the building to simulate hail storms,” said Tim Reinhold, senior vice president of research at Tampa-based IBHS. The goal is to improve building codes and maintenance practices in disaster-prone regions. Such labs, insurers say, help reduce their exposure to catastrophic losses—even at a cost of $100,000 for each large hurricane simulation. [Washington Post]

IBHS conducted its first tests yesterday, blasting a normally constructed house and another made of stronger materials with winds stirred up by 105 giants fans.

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As Tropical Storm Earl grew into Hurricane Earl this past weekend, NASA had a plan: Fly a plane into it. A DC-8 aircraft, used for NASA’s new Genesis and Rapid Intensification Processes (GRIP) project, darted around the storm to trace the movement of atmospheric aerosols–particles suspended in the air–and to drop weather sensors, giving NASA researchers data on how such storms form and strengthen.

NASA’s DC-8 aircraft left Fort Lauderdale at 10:05 a.m. EDT on Saturday heading for St. Croix for a multi-day deployment that targeted (at that time) Tropical Storm Earl…. On Sunday, August 29, the DC-8 completed an 8.5-hour science flight over (then) Hurricane Earl west of St. Croix. The research aircraft flew at altitudes of 33,000 feet and 37,000 feet and descended to 7,000 feet northwest of the storm area to collect measurements of atmospheric aerosols. The flight originated in St. Croix but diverted to land in Fort Lauderdale, Fla., due to the degrading weather forecast for St. Croix associated with the approaching hurricane. [NASA]

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The fires in western Russia continue to burn. Though the overall area now ablaze has shrunk, the number of individual fires has actually risen today. The death rate in Moscow has doubled, and Russia is racing to stop the flames from spreading to areas still affected by radiation from the Chernobyl nuclear disaster a quarter-century ago.

While firefighting goes on, attention turns to the “why?” Russia‘s fire explosion has people wondering if there’s a bigger reason behind it. The topic seems particularly urgent because another major natural disaster is happening not so far away: in northern Pakistan, where exceptionally heavy monsoon rains have caused crushing floods. The big question–whether global warming is responsible–is still unanswered, but scientists do agree that a large weather pattern links the events.

According to meteorologists monitoring the atmosphere above the northern hemisphere, unusual holding patterns in the jet stream are to blame. As a result, weather systems sat still. Temperatures rocketed and rainfall reached extremes [New Scientist].

You’ve probably seen diagrams of the jet stream on weather charts, where a thick band represents its air currents that surge from west to east. However, New Scientist reports, a “blocking event” caused by west-pushing Rossby waves has slowed the jet stream’s flow. This happens from time to time, and it sets the stage for extreme conditions when weather systems hover over the same area.

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A brutal Mount Everest storm might have doomed legendary climber George Mallory. How do we know? Because it’s there—in his team’s meteorological records.

Mallory was the man who, according to legend at least, responded to a question about why he’d want to climb Everest with the immortal reply, “Because it’s there.” But he and his partner, Andrew Irvine, never returned from their 1924 attempt to summit the world’s highest peak. Their lost expedition spurred decades of curiosity about their fate, a curiosity that only intensified when explorers found Mallory’s body in 1999.

For a paper published in the journal Weather, scientists have scoured the meteorological measurements taken at the expedition’s base camp at 16,500 feet and recorded in the logs. Despite the fact that those logs were brought back to Britain in 1926, the researchers argue that they haven’t been part of the discussion of Mallory’s downfall, even though the answer could be right there on the decades-old pages.

The researchers analysed barometric pressure measurements and found that during the Mallory and Irvine summit attempt, there was a pressure drop at Everest base camp of approximately 18 millibars (mbar). Lead author GW Kent Moore, from the University of Toronto, Canada, described this as “quite a large drop”. He said: “We concluded that Mallory and Irvine most likely encountered a very intense storm as they made their way towards the summit” [BBC News].

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The most violent winds in our own solar system whip around the Great Dark Spot of Neptune at 1,200 miles per hour, making the worst storms here on Earth look like kid stuff. But when astronomers trained their telescopes on one of the longest-studied planets around another star, suddenly even Neptune didn’t look so impressive. This week in Nature, astronomers say that the exoplanet HD 209458 b has a super-storm whose winds rage at 3,000 to 6,000 mph.

The exoplanet (which we’ll call by its friendlier nickname, Osiris) sits 150 light years from here, in the neighborhood of the constellation Pegasus. It’s an old friend, too. Osiris was the first exoplanet seen transiting in front of its star back in 1999. A decade later, though, with technology a decade more advanced, the team could spy on Osiris with the a spectrometer at the Very Large Telescope in Chile and track its carbon monoxide signature.

In fact, the VLT’s data is so good that the astronomers could see not only the planet’s orbital speed, but also the relative speed of the gas on its surface, according to study author Ignas Snellen.

“We see this clear change in velocity” of HD 209458 b, Snellen says. “There’s also an offset—the gas during the transit seems to be moving toward us.” The carbon monoxide appears to be flowing at two kilometers per second, or roughly 7,000 kilometers [~4,350 miles] per hour [Scientific American].

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How do you punch a hole in a cloud? Fly through it.

Meteorologists had long figured that aircraft were part of the explanation for crazy-looking “hole-punch clouds” like this one. When propeller planes fly through a cloud, they thought, it can exert air pressure that cools water extremely quickly to produce ice. If water vapor condenses on that ice, snow falls from the sky and leaves a conspicuous cloud hole.

Now, thanks to a happy accident, researchers confirmed that planes can cause these cloud holes, and that even jets, not just prop planes, can do it.

Andrew Heymsfield, a scientist with the National Center for Atmospheric Research, was aboard a research plane near the Denver airport in 2007 when he unwittingly flew through a flurry of snow produced by a hole-punch cloud.

The plane was loaded with instruments for studying how ice forms in clouds. Radar from the ground picked up a strange echo in their wake, indicating oddly-shaped snowflakes. “We didn’t know it, but we went right through this precipitation feature that was spotted from the ground,” Heymsfield said [Wired.com].

Their readings, when matched up with the path of planes in the area, helped unravel the mystery:

The researchers then linked satellite images of hole-punch clouds to flight schedules to show that jet aircraft, not just propeller planes, can also punch holes and produce snow. The supercooled droplets freeze after passing over the jet planes’ wings, Heymsfield said [Wired.com].

Their work will soon be published in the Bulletin of the American Meteorological Society.

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Image: Alan Sealls, chief meteorologist, WKRG-TV

With hurricane season fast approaching, the official forecasts are coming out. And they’re not good. The National Oceanic and Atmospheric Administration estimates that between 14 and 23 storms could reach the severity level of a tropical storm—the point at which they get a name.

Of those, eight to 14 are expected to become hurricanes. From three to seven of these could become major hurricanes, with winds exceeding 111 miles an hour. This compares with a long-term average of 11 named storms per season, with six becoming hurricanes and two becoming major hurricanes [Christian Science Monitor].

The warning signs are alarming even experienced hurricane watchers.

The tropics are even warmer than the toasty waters that spurred the 2005 hurricane season into such dizzying activity, with 28 named storms including Katrina, Rita and Wilma…. “The coming season looks very active based upon the latest data we’ve seen,” said Phil Klotzbach, who along with Colorado State University scientist Bill Gray publishes a widely regarded seasonal forecast. “The tropics are super warm right now” [Houston Chronicle].

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The rainmakers of the 21st century may be armed with powerful lasers. New research suggests that zapping clouds with laser beams could trigger the formation of condensation droplets that would fall to the ground as rain. But while the study, published in Nature Photonics, raises the tantalizing hope of bringing on-demand rain to parched regions, some experts argue the technique is unlikely to ever be practical.

For more than 50 years, efforts to try to artificially induce rain have concentrated on ‘cloud seeding’ — scattering small particles of silver iodide into the air to act as ‘condensation nuclei’, or centres around which rain droplets can grow. “The problem is, it’s still not clear that cloud seeding works efficiently,” says optical physicist Jérôme Kasparian at the University of Geneva, Switzerland. “There are also worries about how safe adding silver iodide particles into the air is for the environment” [Nature News].

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What are we going to do with the Intergovernmental Panel on Climate Change?

The panel got itself in major trouble a few weeks ago when it admitted a major goof, that it included a detail in its 2007 report saying the Himalayan glaciers could melt by 2035, which is a huge exaggeration. Chief Rajendra Pachauri stood by the report as a whole as a sound piece of research, and indeed the first section of the four-part series, which is about physics of anthropogenic climate change, has seen no errors surface. That section laid out the evidence that human activities are boosting carbon dioxide levels in the air and are therefore warming the planet. But four mistakes have been discovered in the second report, which attempts to explain how global warming might affect daily life around the world [Christian Science Monitor].

The IPCC’s errors have given ammunition to deniers of global warming, especially U.S. politicians who have spent the recent batch of snowstorms beating their chests over how wrong climate scientists must be for there to be a blizzard in February. (Though to be fair, and in recognition of the fact that all politicians are opportunists, people on the other side have blamed single storms like Hurricane Katrina on climate change, which is just as silly.) So, to save some face for climate science, several scientists have proposed ways to fix the IPCC in this week’s issue of the journal Nature:

1. Split Into Three Panels

The University of East Anglia’s Mike Hulme proposed breaking up the IPCC into three: one group for science, one to evaluate how climate change could alter various regions of the globe, and one to debate policy options. Says Hulme: “This restructuring would allow clearer distinctions to be made in areas that have been troublesome for the IPCC: assessments of published knowledge versus policy analysis and evaluation; the globalized physical sciences versus more geographically and culturally nuanced knowledge; a one-size, top-down model of ownership and governance versus more inclusive, representative and regionally varying forms of governance.”

2. Make it Independent

For German researcher Eduardo Zorita, it’s not just the IPCC’s mistakes that make it lose public trust, it’s the fact that it’s full of government nominees that occupy “a blurred space between science and politics,” and work under unmanageable stress and deadlines. Zorita says the a climate body ought to be more like the US Congressional Budget Office—accountable, but independent.

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When the Copenhagen climate summit ended in disappointment and finger-pointing, we saw again just how difficult it would be to get the world’s nations on board for an agreement to lower greenhouse emissions and slow global warming. This week brings another reminder of how far away we are from meaningful action: We can’t even get past the difference between weather and climate.

It’s bitter cold this week, even for January. Beijing had its coldest morning in almost 40 years and its biggest snowfall since 1951. Britain is suffering through its longest cold snap since 1981 [AP]. The southern United States is in the grip of freezing weather; the Midwest has seen dangerously cold wind chills far below zero. Trying to stave off the inevitable “where’s your global warming now” chants, the AP and other news sources rushed to run pieces trying to get across—one more time—that weather isn’t climate. The chants came, inevitably. But despite pundits and columnists who try to conflate the two to take the same old swings at global warming, a single bout of cold weather—or hot, for that matter—doesn’t actually say diddly squat about long-term climate patterns.

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In a series of dramatic (if blurry) photographs, scientists have captured a rare type of lightning known as a “gigantic jet.” These jets strike up from the thunderclouds instead of down from them towards the earth, according to findings published in Nature Geoscience.

Catching the phenomenon on film has boosted scientists’ understanding of the lightning. “These are not just sparks that come out of the thunderstorm and travel upward and tickle the upper atmosphere. They actually deliver to the upper atmosphere as much electric charge as the very strong lightning strokes to ground” [BBC], says lead author Steven Cummer. Capturing gigantic jets as they occur is difficult because they occur infrequently, and because scientists don’t yet know which types of storms promote their formation. Cummer got his shot by luck. He had his cameras trained on the clouds brewed by the 2008 tropical storm Cristobal, hoping to spot another form of electrical discharge, when the jet blasted upward, reaching 40 miles into the upper atmosphere.

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Image: Steven Cummer