Science & the Public: HIPPO reveals climate surprises

Swooping pole-to-pole plane flights uncover unexpected trends in pollutant releases and spreadWeb edition : Thursday, September 8th, 2011 Pollutant snifferThis aircraft sampled air at different altitudes along paths that ran from pole to pole looking for climate-altering pollutants.©UCAR/Carlye Calvin

A major pollution-mapping program that ends September 9 has turned up startling trends in climate-warming gases and soot. The data it collected over the past five years from a National Science Foundation aircraft show the tropics periodically belch huge plumes of nitrous oxide — a potent greenhouse gas — into the upper atmosphere. Arctic measurements show that the recent record summer retreats of ice cover have allowed seas there to exhale unexpected amounts of methane, another potent greenhouse gas.

Then there’s soot. Parts of the supposedly pristine Arctic skies host dense clouds of these black carbon particles. During some flights, “We were immersed in essentially clouds of black carbon that were dense enough that you could barely see the ground,” recalls Stephen Wofsy of Harvard University, a principal investigator in the program. “It was like landing in Los Angeles — except that you were 8 kilometers above the surface of the Arctic Ocean.”

Until a few years ago, scientists interested in mapping global emissions of climate-altering pollutants had to rely on Earth-based sensors or satellites’ eyes on the skies. Neither could identify at what altitude the pollutants tended to congregate. They also missed many highly localized or seasonal plumes of natural pollutants.

That all changed when a federal-university research partnership got access to NSF’s research plane: HIAPER (for High Performance Instrumented Airborne Platform for Environmental Research). Throughout a number of periodic runs, this aircraft repeatedly swooped up and down — from 150 meters above Earth’s surface to heights sometimes exceeding 13.7 kilometers (45,000 feet). All along the way, its instruments measured more than 50 greenhouse gases and black carbon.

The unparalleled altitude- and latitude- specific data collected as part of this program — named HIPPO (for HIAPER Pole-to-Pole Observations) — will soon be made available to researchers generally, notes Wofsy. He expects scientists will mine its data for many years, looking for additional climate trends.

Sky-truthing carbon dioxide levels
A primary goal of HIPPO was to investigate how well airborne pollutant concentrations match what computer models had predicted should exist. In some cases, as for soot, HIPPO data pointed to serious problems — oversimplifications — in those models. In other instances, such as for oxygen movement in and out of oceans, the new data generally validated computer predictions.

Currently, land plants and the oceans absorb roughly half of all carbon dioxide emitted, notes Britton Stephens, a scientist with the National Center on Atmospheric Research in Boulder, Colo. But details on which parts of which ecosystems do it, under what circumstances and how efficiently remains somewhat of an open book. Simply put: “We don’t understand their behavior at the current time well enough to predict their behavior into the future,” he says.

So airborne observations have been repeatedly compared to what computer models predict. And one example of where the models need fine tuning involves carbon dioxide, HIPPO indicates.

Little ice, lots of methaneHIPPO ties unexpected release of methane to loss of summer Arctic sea-ice cover (and 2011 may be record loss, Wofsy says).iStockPhoto

It revealed “large plumes of carbon dioxide over the Arctic,” Stephens reported Sept. 7 at a news briefing. These plumes didn’t come from the Arctic, he says, but bled into Arctic skies from industrial centers throughout the Northern Hemisphere.

“This was a bit of a surprise,” he says, because models had suggested that much of the carbon dioxide should have been sucked up by plants and seas close to where the gas was being emitted.

Another instance of where the models appear to fall short is on how well the mixing of near-surface parcels of air homogenize carbon dioxide concentrations.

Stephens pointed to data collected earlier this week by the HIAPER aircraft during a run from Kona, Hawaii, to Anchorage, Alaska. “This is the time of year when we see peak uptake [of the gas]” as a result of photosynthesis in land plants, he explains. And HIPPO indeed observed a large depletion of carbon dioxide near the surface, he notes — except “we were measuring it over the middle of the Pacific Ocean.”

Computer analyses had predicted a greater degree of mixing of clean and polluted air parcels, he says. Instead, there were sharp gradients in the gas among closely sampled regions.

Elsewhere, HIPPO offered welcome confirmation of a different model prediction: large plumes of oxygen coming out of the southern oceans during the austral summer. Stephens attributes these massive releases to the uptake of carbon dioxide by photosynthetic bacteria in the warming seas. Currently, it’s winter in the South. And HIPPO has just measured the opposite trend, Stephens says: a seasonal absorption of oxygen by oceans there.

Similar trends for these gases have been observed before throughout the Northern Hemisphere. But HIPPO shows that this normal pattern of winter absorption of oxygen and summer absorption of carbon dioxide “is somewhat decoupled” in the southern oceans. Indeed, Stephens concludes, at times “it was almost more significant that we measured an anti-correlation between oxygen and carbon dioxide than the actual numbers [of how much of either was present].”

Other revelations
More unexpected, Wofsy says, was the March 2010 finding of “a significant excess over the tropics of greenhouse gases — especially nitrous oxide — very high up in the atmosphere. That hadn’t been predicted by any models.”

So radical were the data that his team rushed them into print. Those data show a “bulge” in nitrous oxide emissions between the equator and 20° North latitude.

“It is clear that the enhanced nitrous oxide seen at altitude is a product of tropical emissions lofted to the middle and upper troposphere by convection,” the authors conclude in the Aug. 6, 2011, Geophysical Research Letters.  HIPPO data alone cannot confirm whether the release of this gas represents a “winking on and off” of emissions on time scales of days to weeks, the researchers said, or whether the releases occur more chronically but only occasionally shoot up to altitudes of between 2 kilometers and 14 kilometers.

The best explanation for these data, Wofsy and his coauthors write, is that rainfall or regional flooding spurs production of the gas (probably by soil microbes) — and when this coincides with sharp atmospheric updrafts, the pollutant is propelled high into the skies.

Something too new to fully understand (although a report on it is being prepared for publication), Wofsy says, is a finding of notable concentrations of methane in the Arctic’s atmosphere that trace back to the sea.

“Oceanographers have known for some time that there is production of methane in surface waters of the Arctic,” he says, but “it’s never been observed in the atmosphere.” Those oceanographic data, he says, suggest a source for this methane other than sediments or the melting of icy gas hydrates.

The phenomenon also appears very widespread. “We observed that the ocean surface releases methane to the atmosphere all over the whole of the Arctic Ocean,” Wofsy says.

Climate scientists have been concerned about whether the Arctic Ocean's loss of summer ice cover might lead, through some feedback mechanisms, to boosting the release of methane. Concludes Wofsy: Thanks to HIPPO, “This hypothesized feedback has been observed for the first time.” And there are hints, he adds, that methane’s source may be something other than melting of gas hydrates.

One notable take-home message from HIPPO: Climate-altering pollution from the Northern Hemisphere — home to 95 percent of humanity — has been migrating everywhere, even into southern skies, says James Elkins of the National Oceanic and Atmospheric Administration, in Boulder. The data are “just very persuasive.”

Indeed, Wofsy adds, after reviewing HIPPO data, you’re left with an impression that pollution associated with human activities has exerted “an overwhelming influence” on Earth’s atmosphere. And that’s not, he adds, reassuring.

Found in: Climate Change, Earth, Environment and Molecules

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Novel geothermal technology packs a one-two punch against climate change

ScienceDaily (June 7, 2011) — Two University of Minnesota Department of Earth Sciences researchers have developed an innovative approach to tapping heat beneath Earth's surface. The method is expected to not only produce renewable electricity far more efficiently than conventional geothermal systems, but also help reduce atmospheric carbon dioxide (CO2) -- dealing a one-two punch against climate change.

The approach, termed CO2-plume geothermal system, or CPG, was developed by Earth sciences faculty member Martin Saar and graduate student Jimmy Randolph in the university's College of Science and Engineering. The research was published in the most recent issue of Geophysical Research Letters. The researchers have applied for a patent and plan to form a start-up company to commercialize the new technology.

Established methods for transforming Earth's heat into electricity involve extracting hot water from rock formations several hundred feet from Earth's surface at the few natural hot spots around the world, then using the hot water to turn power-producing turbines. The university's novel system was born in a flash of insight on a northern Minnesota road trip and jump-started with $600,000 in funding from the U of M Institute on the Environment's Initiative for Renewable Energy and the Environment (IREE). The CPG system uses high-pressure CO2 instead of water as the underground heat-carrying fluid.

CPG provides a number of advantages over other geothermal systems, Randolph said. First, CO2 travels more easily than water through porous rock, so it can extract heat more readily. As a result, CPG can be used in regions where conventional geothermal electricity production would not make sense from a technical or economic standpoint.

"This is probably viable in areas you couldn't even think about doing regular geothermal for electricity production," Randolph said. "In areas where you could, it's perhaps twice as efficient."

CPG also offers the benefit of preventing CO2 from reaching the atmosphere by sequestering it deep underground, where it cannot contribute to climate change. In addition, because pure CO2 is less likely than water to dissolve the material around it, CPG reduces the risk of a geothermal system not being able to operate for long times due to "short-circuiting" or plugging the flow of fluid through the hot rocks. Moreover, the technology could be used in parallel to boost fossil fuel production by pushing natural gas or oil from partially depleted reservoirs as CO2 is injected.

Saar and Randolph first hit on the idea behind CPG in the fall of 2008 while driving to northern Minnesota together to conduct unrelated field research. The two had been conducting research on geothermal energy capture and separately on geologic CO2 sequestration.

"We connected the dots and said, 'Wait a minute -- what are the consequences if you use geothermally heated CO2?'" recalled Saar. "We had a hunch in the car that there should be lots of advantages to doing that."

After batting the idea around a bit, the pair applied for and received a grant from the Initiative for Renewable Energy and the Environment, which disburses funds from Xcel Energy's Renewable Development Fund to help launch potentially transformative projects in emerging fields of energy and the environment. The IREE grant paid for preliminary computer modeling and allowed Saar and Randolph to bring on board energy policy, applied economics and mechanical engineering experts from the University of Minnesota as well as modeling experts from Lawrence Berkeley National Laboratory. It also helped leverage a $1.5 million grant from the U.S. Department of Energy to explore subsurface chemical interactions involved in the process.

"The IREE grant was really critical," Saar said. "This is the kind of project that requires a high-risk investment. I think it's fair to say that there's a good chance that it wouldn't have gone anywhere without IREE support in the early days."

Saar and Randolph have recently applied for additional DOE funding to move CPG forward to the pilot phase.

"Part of the beauty of this is that it combines a lot of ideas but the ideas are essentially technically proven, so we don't need a lot of new technology developed," Randolph said.

"It's combining proven technology in a new way," Saar said. "It's one of those things where you know how the individual components work. The question is, how will they perform together in this new way? The simulation results suggest it's going to be very favorable."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Minnesota.

Journal Reference:

Jimmy B. Randolph, Martin O. Saar. Combining geothermal energy capture with geologic carbon dioxide sequestration. Geophysical Research Letters, 2011; 38 (10) DOI: 10.1029/2011GL047265

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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First habitable exoplanet? Climate simulation reveals new candidate that could support Earth-like life

ScienceDaily (May 16, 2011) — The planetary system around the red dwarf Gliese 581, one of the closest stars to the Sun in the galaxy, has been the subject of several studies aiming to detect the first potentially habitable exoplanet. Two candidates have already been discarded, but a third planet, Gliese 581d, can be considered the first confirmed exoplanet that could support Earth-like life. This is the conclusion of a team of scientists from the Institut Pierre Simon Laplace (CNRS, UPMC, ENS Paris, Ecole Polytechnique) in Paris, France, whose study is published in The Astrophysical Journal Letters.

Are there other planets inhabited like Earth, or at least habitable? The discovery of the first habitable planet has become a quest for many astrophysicists who look for rocky planets in the "habitable zone" around stars, the range of distances in which planets are neither too cold nor too hot for life to flourish.

In this quest, the red dwarf star Gliese 581 has already received a huge amount of attention. In 2007, scientists reported the detection of two planets orbiting not far from the inner and outer edge of its habitable zone. While the more distant planet, Gliese 581d, was initially judged to be too cold for life, the closer-in planet was thought to be potentially habitable by its discoverers. However, later analysis by atmospheric experts showed that if it had liquid oceans like Earth, they would rapidly evaporate in a 'runaway greenhouse' effect similar to that which gave Venus the hot, inhospitable climate it has today. A new possibility emerged late in 2010, when a team of observers led by Steven Vogt at the University of California, Santa Cruz, announced that they had discovered a new planet, which they dubbed Gliese 581g, or 'Zarmina's World'. This planet, they claimed, had a mass similar to that of Earth and was close to the centre of the habitable zone. For several months, the discovery of the first potential Earth twin outside the Solar System seemed to have been achieved. Unfortunately, later analysis by independent teams has raised serious doubts on this extremely difficult detection. Many now believe that Gliese 581g may not exist at all. Instead, it may simply be a result of noise in the ultra-fine measurements of stellar 'wobble' needed to detect exoplanets in this system.

Today, it is finally Gliese 581g's big brother -- the larger and more distant Gliese 581d -- which has been shown to be the confirmed potentially habitable exoplanet by Robin Wordsworth, François Forget and co-workers from Laboratoire de Météorologie Dynamique (CNRS, UPMC, ENS Paris, Ecole Polytechnique) at the Institute Pierre Simon Laplace in Paris. Although it is likely to be a rocky planet, it has a mass at least seven times that of Earth, and is estimated to be about twice its size. At first glance, Gliese 581d is a pretty poor candidate in the hunt for life: it receives less than a third of the stellar energy Earth does and may be tidally locked, with a permanent day and night side. After its discovery, it was generally believed that any atmosphere thick enough to keep the planet warm would become cold enough on the night side to freeze out entirely, ruining any prospects for a habitable climate.

To test whether this intuition was correct, Wordsworth and colleagues developed a new kind of computer model capable of accurately simulating possible exoplanet climates. The model simulates a planet's atmosphere and surface in three dimensions, rather like those used to study climate change on Earth. However, it is based on more fundamental physical principles, allowing the simulation of a much wider range of conditions than would otherwise be possible, including any atmospheric cocktail of gases, clouds and aerosols.

To their surprise, they found that with a dense carbon dioxide atmosphere -- a likely scenario on such a large planet -- the climate of Gliese 581d is not only stable against collapse, but warm enough to have oceans, clouds and rainfall. One of the key factors in their results was Rayleigh scattering, the phenomenon that makes the sky blue on Earth. In the Solar System, Rayleigh scattering limits the amount of sunlight a thick atmosphere can absorb, because a large portion of the scattered blue light is immediately reflected back to space. However, as the starlight from Gliese 581 is red, it is almost unaffected. This means that it can penetrate much deeper into the atmosphere, where it heats the planet effectively due to the greenhouse effect of the CO2 atmosphere, combined with that of the carbon dioxide ice clouds predicted to form at high altitudes. Furthermore, the 3D circulation simulations showed that the daylight heating was efficiently redistributed across the planet by the atmosphere, preventing atmospheric collapse on the night side or at the poles.

Scientists are particularly excited by the fact that at 20 light years from Earth, Gliese 581d is one of our closest galactic neighbours. For now, this is of limited use for budding interstellar colonists -- the furthest-travelled human-made spacecraft, Voyager 1, would still take over 300,000 years to arrive there. However, it does mean that in the future telescopes will be able to detect the planet's atmosphere directly. While Gliese 581d may be habitable there are other possibilities; it could have kept some atmospheric hydrogen, like Uranus and Neptune, or the fierce wind from its star during its infancy could even have torn its atmosphere away entirely. To distinguish between these different scenarios, Wordsworth and co-workers came up with several simple tests that observers will be able to perform in future with a sufficiently powerful telescope.

If Gliese 581d does turn out to be habitable, it would still be a pretty strange place to visit -- the denser air and thick clouds would keep the surface in a perpetual murky red twilight, and its large mass means that surface gravity would be around double that on Earth. But the diversity of planetary climates in the galaxy is likely to be far wider than the few examples we are used to from the Solar System. In the long run, the most important implication of these results may be the idea that life-supporting planets do not in fact need to be particularly like Earth at all.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by CNRS (Délégation Paris Michel-Ange).

Journal Reference:

Robin D. Wordsworth, François Forget, Franck Selsis, Ehouarn Millour, Benjamin Charnay, Jean-Baptiste Madeleine. Gliese 581d is the first discovered terrestrial-mass exoplanet in the habitable zone. The Astrophysical Journal, 2011; 733 (2): L48 DOI: 10.1088/2041-8205/733/2/L48

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

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Gallery: Building the NPP Climate Satellite

138 years of Popular Science at your fingertips.

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First habitable exoplanet? Climate simulation reveals new candidate that could support Earth-like life

ScienceDaily (May 16, 2011) — The planetary system around the red dwarf Gliese 581, one of the closest stars to the Sun in the galaxy, has been the subject of several studies aiming to detect the first potentially habitable exoplanet. Two candidates have already been discarded, but a third planet, Gliese 581d, can be considered the first confirmed exoplanet that could support Earth-like life. This is the conclusion of a team of scientists from the Institut Pierre Simon Laplace (CNRS, UPMC, ENS Paris, Ecole Polytechnique) in Paris, France, whose study is published in The Astrophysical Journal Letters.

Are there other planets inhabited like Earth, or at least habitable? The discovery of the first habitable planet has become a quest for many astrophysicists who look for rocky planets in the "habitable zone" around stars, the range of distances in which planets are neither too cold nor too hot for life to flourish.

In this quest, the red dwarf star Gliese 581 has already received a huge amount of attention. In 2007, scientists reported the detection of two planets orbiting not far from the inner and outer edge of its habitable zone. While the more distant planet, Gliese 581d, was initially judged to be too cold for life, the closer-in planet was thought to be potentially habitable by its discoverers. However, later analysis by atmospheric experts showed that if it had liquid oceans like Earth, they would rapidly evaporate in a 'runaway greenhouse' effect similar to that which gave Venus the hot, inhospitable climate it has today. A new possibility emerged late in 2010, when a team of observers led by Steven Vogt at the University of California, Santa Cruz, announced that they had discovered a new planet, which they dubbed Gliese 581g, or 'Zarmina's World'. This planet, they claimed, had a mass similar to that of Earth and was close to the centre of the habitable zone. For several months, the discovery of the first potential Earth twin outside the Solar System seemed to have been achieved. Unfortunately, later analysis by independent teams has raised serious doubts on this extremely difficult detection. Many now believe that Gliese 581g may not exist at all. Instead, it may simply be a result of noise in the ultra-fine measurements of stellar 'wobble' needed to detect exoplanets in this system.

Today, it is finally Gliese 581g's big brother -- the larger and more distant Gliese 581d -- which has been shown to be the confirmed potentially habitable exoplanet by Robin Wordsworth, François Forget and co-workers from Laboratoire de Météorologie Dynamique (CNRS, UPMC, ENS Paris, Ecole Polytechnique) at the Institute Pierre Simon Laplace in Paris. Although it is likely to be a rocky planet, it has a mass at least seven times that of Earth, and is estimated to be about twice its size. At first glance, Gliese 581d is a pretty poor candidate in the hunt for life: it receives less than a third of the stellar energy Earth does and may be tidally locked, with a permanent day and night side. After its discovery, it was generally believed that any atmosphere thick enough to keep the planet warm would become cold enough on the night side to freeze out entirely, ruining any prospects for a habitable climate.

To test whether this intuition was correct, Wordsworth and colleagues developed a new kind of computer model capable of accurately simulating possible exoplanet climates. The model simulates a planet's atmosphere and surface in three dimensions, rather like those used to study climate change on Earth. However, it is based on more fundamental physical principles, allowing the simulation of a much wider range of conditions than would otherwise be possible, including any atmospheric cocktail of gases, clouds and aerosols.

To their surprise, they found that with a dense carbon dioxide atmosphere -- a likely scenario on such a large planet -- the climate of Gliese 581d is not only stable against collapse, but warm enough to have oceans, clouds and rainfall. One of the key factors in their results was Rayleigh scattering, the phenomenon that makes the sky blue on Earth. In the Solar System, Rayleigh scattering limits the amount of sunlight a thick atmosphere can absorb, because a large portion of the scattered blue light is immediately reflected back to space. However, as the starlight from Gliese 581 is red, it is almost unaffected. This means that it can penetrate much deeper into the atmosphere, where it heats the planet effectively due to the greenhouse effect of the CO2 atmosphere, combined with that of the carbon dioxide ice clouds predicted to form at high altitudes. Furthermore, the 3D circulation simulations showed that the daylight heating was efficiently redistributed across the planet by the atmosphere, preventing atmospheric collapse on the night side or at the poles.

Scientists are particularly excited by the fact that at 20 light years from Earth, Gliese 581d is one of our closest galactic neighbours. For now, this is of limited use for budding interstellar colonists -- the furthest-travelled human-made spacecraft, Voyager 1, would still take over 300,000 years to arrive there. However, it does mean that in the future telescopes will be able to detect the planet's atmosphere directly. While Gliese 581d may be habitable there are other possibilities; it could have kept some atmospheric hydrogen, like Uranus and Neptune, or the fierce wind from its star during its infancy could even have torn its atmosphere away entirely. To distinguish between these different scenarios, Wordsworth and co-workers came up with several simple tests that observers will be able to perform in future with a sufficiently powerful telescope.

If Gliese 581d does turn out to be habitable, it would still be a pretty strange place to visit -- the denser air and thick clouds would keep the surface in a perpetual murky red twilight, and its large mass means that surface gravity would be around double that on Earth. But the diversity of planetary climates in the galaxy is likely to be far wider than the few examples we are used to from the Solar System. In the long run, the most important implication of these results may be the idea that life-supporting planets do not in fact need to be particularly like Earth at all.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by CNRS (Délégation Paris Michel-Ange).

Journal Reference:

Robin D. Wordsworth, François Forget, Franck Selsis, Ehouarn Millour, Benjamin Charnay, Jean-Baptiste Madeleine. Gliese 581d is the first discovered terrestrial-mass exoplanet in the habitable zone. The Astrophysical Journal, 2011; 733 (2): L48 DOI: 10.1088/2041-8205/733/2/L48

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

View the original article here

As Congress Fusses Over Climate Semantics, the U.S. Faces a Weather Satellite Gap

Weather monitoring is vital, but don't mention the C-word
NPOESS Engineers begin integration of the Medium resolution Visible and Infra-red Imager or VIIRS into the NPOESS Preparatory Project NASA/Ball Aerospace

This year has seen some phenomenally bizarre weather, from deadly tornadoes ripping through the Midwest and South to historic snowmelt-related flooding on the Mississippi River. Most hurricane forecasters are saying it’s about to get worse — the National Oceanic and Atmospheric Administration projected Thursday that the Atlantic basin is likely to see 12 to 18 named storms this season.

Amid all this, the country’s future weather prediction capabilities could be stymied by a battle in Washington.

During the budget battle earlier this spring, Congress cut funding for a new polar-orbiting satellite, which is designed to monitor atmospheric temperatures and pressure, severe weather, fires and other manmade and natural disasters, and to provide continuous climate data. If it does not get built, the country faces a satellite gap, which could affect forecasters’ ability to predict the weather.

The key word here is climate.

“Weather is apolitical, but climate is unfortunately not,” Bill Sullivan, a director at Raytheon Intelligence and Information Systems and program manager for the new satellite, said in an interview.

Click here to launch a gallery of images of NASA's NPP satellite

NOAA Administrator Jane Lubchenco said at a news conference Thursday that the agency’s satellite program is in limbo.

This is at least the fourth time in the past few years that a climate-monitoring project has fallen victim to either terrible luck or bad politics. First the Orbiting Carbon Observatory failed to reach orbit, then NASA’s aerosol-monituring Glory mission also died during launch. Last month we told you about the Deep Space Climate Observatory, languishing in a box in Maryland. Now a satellite called JPSS is in danger of losing its funding.

Here’s a bit of history: Until last year, NASA, NOAA and the Department of Defense were going to share a brand-new polar-orbiting satellite called the National Polar Orbiting Operational Environmental Satellite System (NPOESS). But after a few years of planning and design work, the government decided the military and civilian agencies didn’t play well together and divorced the project, giving the DOD its own satellite. The existing civilian project, called NPP for NPOESS Preparatory Project, will serve NASA and NOAA only, and is planned for launch in October. It just completed a thermal test.

It is supposed to have a companion successor called the Joint Polar Satellite System, and NOAA requested $1.06 billion in this year’s budget to build it. Then the federal budget stalemate happened, and everything was funded at 2010 levels as Congress and the White House wrangled.

“The message that was getting to Congress was that NOAA needed a billion dollars to do climate research,” said Sullivan, who is Raytheon’s program manager for the JPSS. As a result, the funding was not approved.

Since the funding cuts, NOAA — and contractors like Raytheon — have started marketing the satellite's weather forecasting abilities, not just its utility in informing climate models.

Polar-orbiting satellites can provide global weather coverage, which is useful when trying to make future weather predictions. Geostationary satellites, like the ones that provide the satellite radar imagery on your local news, only look at a specific section of the planet. The National Weather Service needs both sets of data to complete accurate forecasting.

NPP is a new polar-orbiting satellite that will replace NOAA’s previous orbiters, Sullivan said. It will circle the Earth 512 miles above the surface, completing about 14 orbits every day.

“We’re going to see just a huge increase in the amount of data that can be collected ... NPP provides an enormous amount of capability that is currently not on orbit,” Sullivan said.

NPP will have a life span of about five years, at which point JPSS should be ready to replace it. Sullivan said NOAA needs funding this year for construction so the JPSS project doesn’t fall behind schedule. NOAA is hoping the project will get funding this year, but it looks doubtful, Sullivan said. Meanwhile, the agency is preparing for a budget battle next year, he said.

"If the program doesn't get funded at the appropriate level in 2012, it will fall behind, which is bad for all of us," he said.

“Not having satellites and not applying their latest capabilities could spell disaster,” said NOAA's Lubchenko. “We are likely looking at a period of time a few years down the road where we will not be able to do severe storm warnings and long-term weather forecasts that people have come to expect today.”

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Effects of climate change in Arctic more extensive than expected, report finds

ScienceDaily (May 4, 2011) — A much reduced covering of snow, shorter winter season and thawing tundra: The effects of climate change in the Arctic are already here. And the changes are taking place significantly faster than previously thought. This is what emerges from a new research report on the Arctic, presented in Copenhagen this week. Margareta Johansson, from Lund University, is one of the researchers behind the report.

Together with Terry Callaghan, a researcher at the Royal Swedish Academy of Sciences, Margareta is the editor of the two chapters on snow and permafrost.

"The changes we see are dramatic. And they are not coincidental. The trends are unequivocal and deviate from the norm when compared with a longer term perspective," she says.

The Arctic is one of the parts of the globe that is warming up fastest today. Measurements of air temperature show that the most recent five-year period has been the warmest since 1880, when monitoring began. Other data, from tree rings among other things, show that the summer temperatures over the last decades have been the highest in 2000 years. As a consequence, the snow cover in May and June has decreased by close to 20 per cent. The winter season has also become almost two weeks shorter -- in just a few decades. In addition, the temperature in the permafrost has increased by between half a degree and two degrees.

"There is no indication that the permafrost will not continue to thaw," says Margareta Johansson.

Large quantities of carbon are stored in the permafrost.

"Our data shows that there is significantly more than previously thought. There is approximately double the amount of carbon in the permafrost as there is in the atmosphere today," says Margareta Johansson.

The carbon comes from organic material which was "deep frozen" in the ground during the last ice age. As long as the ground is frozen, the carbon remains stable. But as the permafrost thaws there is a risk that carbon dioxide and methane, a greenhouse gas more than 20 times more powerful than carbon dioxide, will be released, which could increase global warming.

"But it is also possible that the vegetation which will be able to grow when the ground thaws will absorb the carbon dioxide. We still know very little about this. With the knowledge we have today we cannot say for sure whether the thawing tundra will absorb or produce more greenhouse gases in the future," says Margareta Johansson.

Effects of this type, so-called feedback effects, are of major significance for how extensive global warming will be in the future. Margareta Johansson and her colleagues present nine different feedback effects in their report. One of the most important right now is the reduction of the Arctic's albedo. The decrease in the snow- and ice-covered surfaces means that less solar radiation is reflected back out into the atmosphere. It is absorbed instead, with temperatures rising as a result. Thus the Arctic has entered a stage where it is itself reinforcing climate change.

The future does not look brighter. Climate models show that temperatures will rise by a further 3 to 7 degrees. In Canada, the uppermost metres of permafrost will thaw on approximately one fifth of the surface currently covered by permafrost. The equivalent figure for Alaska is 57 per cent. The length of the winter season and the snow coverage in the Arctic will continue to decrease and the glaciers in the area will probably lose between 10 and 30 per cent of their total mass. All this within this century and with grave consequences for the ecosystems, existing infrastructure and human living conditions.

New estimates also show that by 2100, the sea level will have risen by between 0.9 and 1.6 metres, which is approximately twice the increase predicted by the UN's panel on climate change, IPCC, in its 2007 report. This is largely due to the rapid melting of the Arctic icecap. Between 2003 and 2008, the melting of the Arctic icecap accounted for 40 per cent of the global rise in sea level.

"It is clear that great changes are at hand. It is all happening in the Arctic right now. And what is happening there affects us all," says Margareta Johansson.

The report "Impacts of climate change on snow, water, ice and permafrost in the Arctic" has been compiled by close to 200 polar researchers. It is the most comprehensive synthesis of knowledge about the Arctic that has been presented in the last six years. The work was organised by the Arctic Council's working group for environmental monitoring (the Arctic Monitoring and Assessment Programme) and will serve as the basis for the IPCC's fifth report, which is expected to be ready by 2014.

Besides Margareta Johansson, Torben Christensen from Lund University also took part in the work.

More information on the report and The Artic as a messenger for global processes - climate change and pollution conference in Copenhagen can be found at: http://amap.no/Conferences/Conf2011/

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Lund University.

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Climate action could save polar bears

HANGING ONSustainable populations of polar bears might be possible in shrinking Arctic sea ice after all, new research suggests.Steven C. Amstrup/Polar Bears International

Cutting greenhouse gas emissions enough over the next few decades may stabilize the rapidly shrinking Arctic sea ice sufficiently to provide a sustainable habitat for polar bears, a paper in the Dec. 16 Nature reports. And if emissions do keep rising, another new study finds, the only species that has officially been declared threatened by the U.S. government due to global warming may still be able to hang on for a while in a few pockets of the northern Arctic.

Polar bears need sea ice to hunt their prey, but the frozen skin that floats atop the Arctic Ocean has been thinning and shrinking in recent decades as global temperatures rise. Between 1979 and 2010, Arctic sea ice cover at the end of the summer melt season dropped an average of 11.5 percent per decade. Many researchers think that end-summer Arctic ice could be almost entirely gone by the middle of this century.

In 2007, the U.S. Geological Survey reported that two-thirds of the world’s 25,000 polar bears could disappear within 50 years if greenhouse gas emissions continued unabated. The following year, interior secretary Dirk Kempthorne relied on that report when putting the bear, Ursus maritimus, on the government’s list of threatened species.

Steven Amstrup, an Anchorage-based senior scientist with Polar Bears International in Bozeman, Mont., who was a coauthor on the 2007 USGS report, decided to look at whether cutting emissions could preserve enough of the Arctic sea ice to save polar bears from extinction.

In the Nature paper, his team studied five scenarios for how much atmospheric levels of greenhouse gases would rise over the next century.

Using a widely accepted climate model, the researchers analyzed potential futures for several measures of sea ice habitability — such as the amount of sea ice extending over continental shelves, the number of months each year those shelves are free of ice and the distance between that ice and the more northerly pack ice that bears also use to hunt.

The results don’t support the idea that Arctic sea ice is headed for a catastrophic “tipping point” beyond which the ice disintegrates completely, Amstrup says. Instead, if greenhouse gas emissions and hence temperatures can be stabilized, the sea ice stabilizes too.

“If we act, it isn’t too late to save the polar bear,” Amstrup says.

As it thins, sea ice reaches a point where it becomes more responsive to the water temperature below and is better able to regrow in the winter , says Marika Holland, a sea ice specialist at the National Center for Atmospheric Research in Boulder, Colo. This enhanced growth helps stabilize the shrinking ice.

Still, the more people can limit greenhouse gas emissions, the less melting will happen in the first place, says Amstrup.

Even if emissions keep rising, sea ice will stick around in certain areas of the Arctic longer than others, Stephanie Pfirman, an Arctic specialist at Barnard College in New York and the nearby Lamont-Doherty Earth Observatory, and her colleagues will report in San Francisco December 16 at the annual meeting of the American Geophysical Union. The work meshes nicely with the new Nature paper, she said: “They’re asking what happens if we act to mitigate. We’re looking at the base case: What if we don’t act?”

Winds and ocean circulation regularly pile ice up in the Canadian Arctic archipelago and north of Greenland, Pfirman said. Sea ice is thick there today and may persist long after it has melted elsewhere, the researchers propose.

Polar bears aren’t the only creatures that may depend on those last remnants of ice cover, Pfirman noted. An entire ecosystem, including seals and walruses, depends on sea ice. On December 3, the National Oceanic and Atmospheric Administration proposed listing four subspecies of ringed seal and two populations of bearded seal as threatened because of shrinking ice. It is the first such proposal since the polar bear based solely on the threat of climate change. 

By 2100 only the northern fringes of Canada and Greenland — the same areas Pfirman’s group identified in its polar bear study — will have snow deep enough to shelter ringed seal pups, suggests research presented at the AGU meeting by Brendan Kelly, a marine-mammal specialist at NOAA’s National Marine Mammal Laboratory in Juneau, Alaska, and Cecilia Bitz, a sea ice physicist at the University of Washington in Seattle. Each spring, these seals make snow caves atop the ice to shelter their newborn pups; to do so, they need snow at least 50 centimeters deep.

But in a greenhouse world, these high Arctic pockets will last only so long, says Robert Newton, an oceanographer at Lamont-Doherty.

“This [refuge] is not expected to last forever,” Newton says. “As the planet keeps warming, it will eventually be lost.”

Back Story | Where the bears are

The International Union for Conservation of Nature puts polar bears into 19 subpopulations. Shown are estimated numbers of bears in 15 of the groups with years of the estimates

Credit: GeoAtlas/Graphi-Ogre, adapted by E. Feliciano

Found in: Climate Change, Earth, Ecology and Environment

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