DaveMurray's Blog

INTERESTING AND FAST PACE WEATHER ON THE WAY OVER THE NEXT SEVERAL DAYS...NO MAJOR STORMS TO TALK ABOUT...BUT DEALING WITH SOME IMPRESSIVE TEMPERATURE SWINGS AND IN THE LONG TERM SOME ARCTIC COLD AND THEN LEADING TO AN IMPRESSIVE JANAURY THAW...SO LOTS GOING ON. BACK EDGE OF THE SYSTEM TOMORROW MORNING WITH SOME LIGHT SNOW AND FLURRIES...COLDER AND WINDY IN THE AFTERNOON...THEN MORE TEMPERATURE SWINGS.

THE DAY TO DAY LOOK:

*** WEDNESDAY...THE SYSTEM PULLS OUT...SOME LIGHT SNOW AND FLURRIES IN THE MORNING...THEN AS IT ALL SWEEPS BY--TURNING WINDY WITH A SLOW DROP IN TEMPERATURE AS GET INTO THE AFTERNOON

*** ANOTHER STRONGER CLIPPER ARRIVES FRIDAY NIGHT...WARMER AHEAD...IN FACT A FAST WARM UP ESPECIALLY ON FRIDAY AFTERNOON...50 PLUS IS POSSIBLE...THEN FRIDAY NIGHT--ALITTLE MORE MOISTURE TO WORK WITH...RAIN SHOWERS AND IN TIME SOME WET SNOW INTO FRIDAY NIGHT...THIS RUNS WITH THE COLDER AIR WORKING IN FROM THE NORTHWEST

*** COLDER AIR CUTS IN FOR THE WEEKEND.

THE LONG RANGE:

IT STILL LOOKS LIKE THIS NEXT COLD SHOT--WHICH IS A SOLID SHOT WILL BE THE LAST REAL TAP OF THE DEEP ARCTIC FOR 5 TO 6 WEEKS...BUT SNOW BUNNIES DON'T GET OVERLY CONCERNED ABOUT THIS...HERE'S WHY...WE TAKE THE COLD AND DRY AIR THAT HAS BEEN PUNCHING IN FROM THE NORTH FOR DECEMBER AND JANAURY...TAKING THE DRY OUT IS THE KEY...THAT HAS BEEN KEEPING OUR MOISTURE HIDDEN. TAKE THAT OUT AND WE OPEN UP A MORE ACTIVE SOUTHERN STORM TRACK...YES THAT WILL LEAD TO THOSE MIXES...BUT ITS THE SOUTHERN STORMS WITH THE BOURDER-LINE TEMPS THAT WILL BRING OUR BIGGER SNOWS. SO SNOW BUNNIES...DON'T TAKE THAT THE ARCTIC COLD IS GETTING SHUT OFF...LOOK AT IT THAT THAT MEANS THE SOUTHERN STORM TRACK BECOMES MORE ACTIVE...HANG IN THERE...NOTHING TO HOP ABOUT RIGHT NOW...BUT HANG TOUGH

IN CASE YOU MISSED MY WINTER FORECAST FOR THIS SEASON JUST FOLLOW THIS LINK:

*** Click Here To See My 2008-2009 Winter Weather Forecast.***

You know how I feel about models...you work hard and forecast...using the models for what they are to be used for guidence...knowing the dynamics and physics of each model and what is good and bad...but a model...is not a forecast. With that said...one of my fav model guidence tool is the European model...here are the 3-4-5-6- day tools to watch for you...Dave

ECMWF SL Pressure/500 mb Height Plot TYPE Norm Inv TIME 3 day 4 day 5 day 6 day 4 Panel

 STAR CHART INFO:  

Jupiter is getting ever lower below Mercury. Can you still find it? The blue 10° scale is about the size of your fist at arm's length. Sky & Telescope diagram

THE COOL PIC OF THE DAY:

The year 2008 will long be remembered as the wettest year on record for St. Louis. Officially, St. Louis recorded 57.96 inches of precipitation in 2008, which was nearly three inches more than the previous record year of 1982.

2008 Weather Events

ST. LOUIS 
(1870-2008)

TOP TEN WETTEST YEARS ON RECORD

 1. 57.96 (2008)
 2. 54.97 (1982)
 3. 54.76 (1993)
 4. 51.65 (1984)
 5. 50.83 (1927)
 6. 50.73 (1985)
 7. 50.31 (1946)
 8. 49.28 (1915)
 9. 49.20 (1898)
10. 48.46 (1876)

Normal = 38.75 
(1971-2000) 

Pacific halibut.

High resolution (Credit: NOAA)

NOAA today proposed reducing the number of halibut that charter vessel anglers in southeast Alaska can keep, from two each day to one.

“Sport charter fishing has grown in southeast Alaska while halibut abundance has decreased,” said Doug Mecum, NOAA’s Fisheries Service acting regional administrator for Alaska. "We’re proposing to reduce the charter halibut catch to protect the halibut resource."

The proposed rule, which would take effect this spring, would allow each charter vessel client to use only one fishing line, and no more than six lines targeting halibut would be allowed on a charter vessel at one time. The rule would prohibit guides and crew from catching and retaining halibut while charter halibut clients are on board.

NOAA’s Fisheries Service put a similar rule in place last spring, but sport charter halibut operators challenged it on procedural grounds and the agency withdrew the rule.

Public comment on the proposed rule is open through Jan. 21, 2009. After considering public comment, NOAA expects to publish a final rule in the spring of 2009. To read the proposed rule and see how to submit comments, go to the NOAA Marine Fisheries Service Alaska Regional Office Web site.

Charter halibut operators in southeast Alaska waters have exceeded their guideline harvest level of 1.43 million pounds for the past four years. The actual sport charter harvest was 1.75 million pounds in 2004, 1.95 million pounds in 2005, 1.86 million pounds in 2006, and 1.92 million pounds in 2007.  The guideline harvest level dropped to 0.93 million pounds for 2008. Managers expect that it will have been exceeded for 2008 when the harvest numbers are final.

The International Pacific Halibut Commission, with representatives from the U.S. and Canada, annually estimates halibut abundance in each halibut fishing area along the Pacific Coast. NOAA’s Fisheries Service, in cooperation with the North Pacific Fishery Management Council, establishes the charter vessel guideline harvest levels based on the commission’s abundance estimates.

The commission annually establishes the commercial halibut fishery catch limits in each area, taking into account charter vessel harvests and other sources of halibut mortality in order to protect the halibut resource from overharvest. 

The commission has reduced the commercial halibut catch in southeast Alaska from nearly 11 million pounds annually between 2004 and 2006 to just over six million pounds for 2008. The final commercial harvest level for 2009, proposed at four and a half million pounds, will be set by the International Pacific Halibut Commission in January.

Saturn's Crazy Christmas Tilt

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Dec. 22, 2008: You look through the telescope. Blink. Shake your head and look again. The planet you expected to see in the eyepiece is not the one that's actually there. Too much eggnog?

No, it's just Saturn's crazy Christmas tilt.

All year long, the rings of Saturn have been tilting toward Earth and now they are almost perfectly edge-on. The opening angle is a paper-thin 0.8o. Viewed from the side, the normally wide and bright rings have become a shadowy line bisecting Saturn's two hemispheres--a scene of rare beauty.

Amateur astronomer Efrain Morales Rivera of Aguadilla, Puerto Rico, has been monitoring Saturn and he created this composite image to show how the geometry has changed:

Astronomers call the phenomenon a "ring plane crossing." As Saturn goes around the sun, it periodically (once every 14 to 15 years) turns its rings edge-on to Earth. Because the rings are so thin, they can actually disappear when viewed through a backyard telescope. At the precise moment of crossing, Saturn undergoes a startling metamorphosis. The ringed planet becomes a lonely ball of gas, almost unrecognizable: Hubble photo.

(Historical note: Shortly after Galileo discovered Saturn's rings in 1610, they disappeared in precisely this fashion. Galileo didn't understand the nature of the rings and the vanishing act confused him mightily. Nevertheless, his physical intuition prevailed. "They'll be back," he predicted, and without ever knowing why, he was correct.)

Sign up for EXPRESS SCIENCE NEWS delivery We're not quite there yet. The opening angle won't be precisely 0o until Sept. 4, 2009. Don't bother marking your calendar, though. Saturn will be so close to the sun, no one will be able to see the rings wink out.

The best time to look is now.

The 0.8o opening angle of Christmas 2008 is the minimum for some time to come. In January 2009 the rings begin to open up again, a temporary reversal caused by the orbital motions of Earth and Saturn. By the time narrowing resumes in summer 2009, Saturn will be approaching the sun; looking through a telescope then could actually be dangerous. The next ring plane crossing that's easy to watch won't come until 2038.

So wake up before sunrise on Dec. 25th, point your telescope at the golden "star" in Leo, and behold Saturn's crazy Christmas tilt: sky map.

High resolution (Credit: /NOAA)

Greenhouse gases play an important role in North American climate, but differences in regional ocean temperatures may hold a key to predicting future U.S. regional climate changes, according to a new NOAA-led scientific assessment. The assessment is one in a series of synthesis and assessment reports coordinated by the U.S. Climate Change Science Program.

This latest assessment, Reanalysis of Historical Climate Data for Key Atmospheric Features: Implications for Attribution of Causes of Observed Change, describes what has changed—and why—in North America’s climate over the past half century. The assessment addresses the likelihood and extent to which human activity or natural variations have driven surface warming, precipitation, droughts, and floods.

“A major implication of this assessment is that improving predictions of regional sea-surface temperatures will be crucial to predicting climate variability across the U.S. from years to decades, as well as projecting long-term regional climate changes,” said Randall Dole, lead author and a scientist at NOAA’s Earth System Research Laboratory in Boulder, Colo.

Some regional temperatures rose sharply, while others held steady; drought impacts worsened; and precipitation swung widely—all within the continent’s gradually warming climate.

Changes in sea-surface temperature patterns likely played an important role in determining differences in U.S. regional temperature trends. They also contributed to large precipitation swings from year to year or decade to decade during the past 50 years.

While a general trend toward warmer ocean conditions is expected with increasing greenhouse gases, regional differences in sea surface temperature trends can be either natural or human-caused, according to Dole. 

The assessment found that an increase in greenhouse gases is likely responsible for more than half of the average continental warming of 1.6° Fahrenheit observed during the past 50 years.  Greenhouse gases, emitted by fossil fuel burning and natural sources, trap heat in Earth’s atmosphere and warm the surface.

Drought impacts have likely become more severe as surface temperatures warmed, increasing evaporation, reducing soil moisture, and causing other water stresses. The scientists found no long-term trends in where or how often droughts occur or in how much rain or snow has fallen on average each year.

The assessment also describes in detail how climate scientists use enormous amounts of data in a powerful method for examining past climate, called “reanalysis.” Another section illustrates how they systematically probe cause-and-effect relationships to find the most likely cause of a climate trend, a prolonged drought, or an unusually hot year – a process termed ‘attribution’.

In a reanalysis—or retrospective analysis—a high-quality climate record is constructed from past observations collected over a period of time from many different observing systems and combined with a climate model. Reanalysis data, which currently extend as far back as the mid-twentieth century, are important in helping researchers understand how climate evolved.

“Using reanalysis and attribution methods we can now say with more confidence what’s driving some of the extreme climate conditions of the past few years: whether it’s global warming, El Niño, La Niña, or some other pattern,” said NOAA scientist Martin Hoerling, also of the Earth System Research Laboratory and a lead author on the report. “That’s the information policymakers and the public ask for.” Hoerling also heads NOAA’s climate attribution team.

Jason-2 satellite.

High resolution (Credit: NOAA)

NOAA announced that scientists around the world now have access to valuable data from a new international satellite, the Jason-2/Ocean Surface Topography Mission. This information allows them to closely watch the rate of global sea-level rise and monitor changing ocean features around tropical cyclones.

Jason-2/OSTM, launched June 20, 2008, is a joint effort between NOAA, the National Aeronautics and Space Administration, France’s Centre National d’Etudes Spatiales (CNES) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). After five months of calibration and validation activities an international team of scientists, including representatives from NOAA, declared the near real-time Jason-2 data were ready for public distribution.

A leading NOAA scientist said data from Jason-2/OSTM is especially crucial now. “The sea level is rising at a rate of 3.2 mm/year, nearly twice as fast as the previous 100 years,” said Laury Miller, chief of NOAA’s Laboratory for Satellite Altimetry. “If this rate continues unchanged during the coming decades, it will have a huge impact on coastal regions, with erosion and flooding. We need the Jason-2 data to help us monitor what’s happening.”

The spacecraft is flying in a low Earth orbit and monitoring 95 percent of the world’s ice-free oceans every 10 days. Like earlier missions TOPEX/Poseidon and Jason-1, Jason-2/OSTM is extending the climate data record by providing a long-term survey of Earth’s oceans, tracking ocean circulation patterns, and measuring sea-surface heights and the rate of sea-level rise. These are critical factors in understanding climate change.

Along with detecting climate change factors, Jason-2/OSTM is being used to assist in forecasting short-term, severe weather events, including tropical cyclones. NOAA will use the altimeter measurements to map the ocean heat content — the fuel that feeds a storm’s intensity — along the storm’s predicted track.

NOAA, working with CNES, is providing ground system support for this mission. This includes: commanding the satellite, downloading all the data and distributing the information to weather and climate forecasters, who are monitoring ocean-born storms and phenomena such as El Niño/La Niña and global sea-level rise. 

Throughout the mission, CNES will continue to monitor and evaluate the satellite and its instruments. EUMETSAT will process and distribute data received by its own ground station to European users and archive the data. NOAA will process and distribute data received by its ground stations to non-European users and archive the data. NASA will evaluate the performance of the Global Positioning System, laser and radiometry instruments and validate scientific products.

“With the successful transition of this important measurement to our partners, NOAA and EUMETSAT, we’ve entered a new era in the long-term monitoring of sea-level from space,” said Lee-Lueng Fu, OSTM/Jason-2 project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

The November 2008 temperature for the contiguous United States was warmer than the long-term average, according to NOAA’s National Climatic Data Center in Asheville, N.C. The January-November 2008 temperature was near average.

The average November temperature of 44.5 degrees F was 2.0 degrees F above the 20th Century average. Precipitation across the contiguous United States in November averaged 1.93 inches, which is 0.20 inch below the 1901-2000 average.

For the January-November period, the average temperature of 54.9 degrees F was 0.3 degree above the 20th Century average. The nation’s January-November temperature has increased at a rate of 0.12 degrees per decade since 1895, and at a faster rate of 0.41 degrees each decade during the last 50 years. All findings are based on a preliminary analysis of data based on records dating back to 1895.

High resolution (Credit: NOAA)

• November temperatures were cooler than average across the Southeast and Central regions, and much warmer than average in the Southwest, Northwest and West regions.

• The West region had its fourth warmest November on record. This contrasted with the Southeast, which was much below normal.

• Persistent above-average temperatures for the last six months have resulted in a record warm June-November period for the West region. California set a record for its warmest June-November, while both Nevada and Utah had their fifth warmest June-November period.

• Based on NOAA's Residential Energy Demand Temperature Index, the contiguous U.S. temperature-related energy demand was 0.6 percent below average in November.

High resolution (Credit: NOAA)

• The United States measured above-normal precipitation across the northern Great Plains from eastern Montana to western Minnesota. However, November was drier than normal across much of the South and Central regions.

• Precipitation across most of the Midwest was only 50-75 percent of normal and some areas from southern Missouri through central Illinois received less than 50 percent of normal precipitation.

• The January-November period has been persistently wet across much of the country from the central Plains to the Northeast. The 11-month period was the wettest on record for New Hampshire and Massachusetts, second wettest for Missouri, third wettest for Vermont and Illinois, and fifth wettest for Maine and Iowa.

• At the end of November, 22 percent of the contiguous United States was in moderate-to-exceptional drought, about the same as October. Meanwhile, extreme-to-exceptional drought conditions continued in the western Carolinas, northeast Georgia, eastern Tennessee, southern Texas, and Hawai’i. 

• About 26 percent of the contiguous United States was in moderately-to-extremely wet conditions at the end of November, according to the Palmer Index. This was a decrease of about three percent compared to October.

• It was the wettest November on record in Yuma, Ariz., with 2.2 inches (5.6 cm) of precipitation – all of it falling on November 26.  This was more than five times the November average.

• An early November blizzard forced more than 100 businesses and schools, and Interstate 90, to close in western South Dakota on Nov. 5 and 6. The blizzard brought total snow accumulations of 3 to 4 feet and drifts up to 20 feet in places.

• Several periods of strong northwesterly winds during the month resulted in mountain-enhanced snowfalls across the mountains of western Virginia, North Carolina, and extreme northern Georgia.  Banner Elk, N.C. recorded 6.2 inches (15.7 cm) of snow during the month making it the snowiest November since 1983.

• Three separate wildfires, which scorched 41,000 acres in Southern California, destroyed 1,000 homes and prompted 15,000 people to evacuate from November 13-17.

NCDC’s preliminary reports, which assess the current state of the climate, are released soon after the end of each month. These analyses are based on preliminary data, which are subject to revision. Additional quality control is applied to the data when late reports are received several weeks after the end of the month and as increased scientific methods improve NCDC’s processing algorithms.

The year 2008 is on track to be one of the 10 warmest years on record for the globe, based on the combined average of worldwide land and ocean surface temperatures, according to a preliminary analysis by NOAA’s National Climatic Data Center in Asheville, N.C. For November alone, the month is fourth warmest all-time globally, for the combined land and ocean surface temperature. The early assessment is based on records dating back to 1880. 

• The combined global land and ocean surface temperature from January – November was 0.86 degree F (0.48 degree C) above the 20th century mean of 57.2 degrees F (14.0 degrees C).

• Separately, the global land surface temperature for 2008 was the fifth warmest, with an average temperature 1.44 degrees F (0.80 degree C) above the 20th century mean of 48.1 degrees F (9.0 degrees C).

• Also separately, the global ocean surface temperature for 2008 was 0.67 degrees F (0.37 degrees C) above the 20th century mean of 61.0 degrees F (16.1 degrees C).

• The November combined global land and ocean surface temperature was 1.06 degrees F (0.59 degree C) above the 20th century mean of 55.2 degrees F (12.9 degrees C).

• Separately, the November 2008 global land surface temperature was fourth warmest on record and was 2.11 degrees F (1.17 degrees C) above the 20th century mean of 42.6 degrees F (5.9 degrees C).

• For November, the global ocean surface temperature was 0.68 degrees F (0.38 degree C) above the 20th century mean of 60.4 degrees F (15.8 degrees C). 

• In the tropical Pacific, 2008 was dominated by El Niño-Southern Oscillation neutral conditions. La Niña conditions that began the year had dissipated by June.  

• Arctic sea ice extent in 2008 reached its second lowest melt season extent on record in September.  The minimum of 1.74 million square miles (4.52 million square kilometers) reached on September 12 was 0.86 million square miles (2.24 million square kilometers) below the 1979-2000 average minimum extent. 

• The 2008 Atlantic hurricane season was the third most costly on record in current dollars, after 2005 and 2004, and the fourth most active year since 1944. This was the first season with a major hurricane (Category 3 or above) each month from July through November. With the exception of the South Indian Ocean, all other tropical cyclone regions recorded near to below-average activity during 2008. Globally, there were 89 named tropical cyclones, with 41 reaching the equivalent of hurricane strength (74 mph), and 20 achieving the equivalent of major hurricane status (111 mph or greater) based on the Saffir-Simpson scale.

• The United States recorded a preliminary total of just under 1,700 tornadoes from January - November. This ranks 2008 second behind 2004 for the most tornadoes in a year, since reliable records began in 1953.

• Torrential rains caused widespread flooding in parts of Vietnam, Ethiopia, northern Venezuela, Brazil, Panama, and the northern Philippines during November. Several million people were displaced and nearly 200 fatalities were reported. Monsoonal rainfall was much above average over many regions in 2008. Mumbai, India, recorded its greatest June rainfall in seven years, while Hanoi, Vietnam, observed its greatest October rains since 1984.

• Persistent severe to exceptional drought plagued portions of south central Texas and the Southeast U.S. in 2008. Based on the Palmer Drought Index, the 2008 percent area of the contiguous United States experiencing moderate-extreme drought peaked at 31 percent in June – July. Australia’s worst drought in a century eased early in 2008, but drought conditions continued in parts of the country.

• Northern Hemisphere snow cover extent in November was 12.66 million square miles (32.78 million square kilometers). This is 0.50 million square miles (1.29 million square kilometers) below the 1966-2008 November average. Northern Hemisphere snow cover extent has been below average for most of 2008.

The analyses in NCDC’s global reports are based on preliminary data, which are subject to revision.  Additional quality control is applied to the data when late reports are received several weeks after the end of the month and as increased scientific methods improve NCDC’s processing algorithms.

NCDC’s ranking of 2008 as ninth warmest if expected trends continue compares to a similar ranking of ninth warmest based on an analysis by NASA’s Goddard Institute for Space Studies. The NASA analysis indicates that the January – November global temperature was 0.76 degree F (0.42 degree C) above the 20th century mean. The NOAA and NASA analyses differ slightly in methodology, but both use data from NOAA's National Climatic Data Center — the federal government's official source for climate data.

Solar Flare Surprise

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Dec. 15, 2008: Solar flares are the most powerful explosions in the solar system. Packing a punch equal to a hundred million hydrogen bombs, they obliterate everything in their immediate vicinity. Not a single atom should remain intact.

At least that's how it's supposed to work.

"We've detected a stream of perfectly intact hydrogen atoms shooting out of an X-class solar flare," says Richard Mewaldt of Caltech. "What a surprise! These atoms could be telling us something new about what happens inside flares."

Above: The X9-class solar flare of Dec. 5, 2006, observed by the Solar X-Ray Imager aboard NOAA's GOES-13 satellite. [Larger image]

The event occurred on Dec. 5, 2006. A large sunspot rounded the sun's eastern limb and with little warning it exploded. On the "Richter scale" of flares, which ranks X1 as a big event, the blast registered X9, making it one of the strongest flares of the past 30 years.

NASA managers braced themselves. Such a ferocious blast usually produces a blizzard of high-energy particles dangerous to both satellites and astronauts. Indeed, moments after the explosion, radio emissions from a shock wave in the sun's atmosphere signaled that a swarm of particles was on its way.

An hour later they arrived. But they were not the particles researchers expected.

NASA's twin STEREO spacecraft made the discovery: "It was a burst of hydrogen atoms," says Mewaldt. "No other elements were present, not even helium (the sun's second most abundant atomic species). Pure hydrogen streamed past the spacecraft for a full 90 minutes."

Next came more than 30 minutes of quiet. The burst subsided and STEREO's particle counters returned to low levels. The event seemed to be over when a second wave of particles enveloped the spacecraft. These were the "broken atoms" that flares are supposed to produce—protons and heavier ions such as helium, oxygen and iron. "Better late than never," he says.

Above: STEREO particle counts on Dec. 5, 2006. The vertical axis measures the angle to the sun. Note how the initial hydrogen burst arrived from a narrow angle while the ions that followed swarmed in from all directions. The "swarming action" is a result of deflections by the sun's magnetic field--a force not felt by the neutral hydrogen.

At first, this unprecedented sequence of events baffled scientists, but now Mewaldt and colleagues believe they're getting to the bottom of the mystery.

First, how did the hydrogen atoms resist destruction?

"They didn't," says Mewaldt. "We believe they began their journey to Earth in pieces, as protons and electrons. Before they escaped the sun’s atmosphere, however, some of the protons recaptured an electron, forming intact hydrogen atoms. The atoms left the sun in a fast, straight shot before they could be broken apart again." (For experts: The team believes the electrons were recaptured by some combination of radiative recombination and charge exchange.)

Sign up for EXPRESS SCIENCE NEWS delivery Second, what delayed the ions?

"Simple," says Mewaldt. "Ions are electrically charged and they feel the sun's magnetic field. Solar magnetism deflects ions and slows their progress to Earth. Hydrogen atoms, on the other hand, are electrically neutral. They can shoot straight out of the sun without magnetic interference."

Imagine two runners dashing for the finish line. One (the ion) is forced to run in a zig-zag pattern with zigs and zags as wide as the orbit of Mars. The other (the hydrogen atom) runs in a straight line. Who's going to win?

"The hydrogen atoms reached Earth two hours before the ions," says Mewaldt.

Mewaldt believes that all strong flares might emit hydrogen bursts, but they simply haven't been noticed before. He's looking forward to more X-flares now that the two STEREO spacecraft are widely separated on nearly opposite sides of the Sun. (In 2006 they were still together near Earth.) STEREO-A and –B may be able to triangulate future bursts and pinpoint the source of the hydrogen. This would allow the team to test their ideas about the surprising phenomenon.

"All we need now," he says, "is some solar activity."

For more information about this research, look for the article "STEREO Observations of Energetic Neutral Atoms during the 5 December 2006 Solar Flare" by R. A. Mewaldt et al, in a future issue of the Astrophysical Journal Letters.

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Author: Dr. Tony Phillips | Credit: Science@NASA

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December 10, 2008: The James Webb Space Telescope, targeted for launch in 2013, is already taking an incredible journey right here on Earth. It's zigzagging up, down, and across the US to be "spit and polished" to perfection for its lofty space mission.

"To find the first stars and galaxies that formed in the early universe, which are millions and even billions of light years away, the Webb telescope mirror has to be wickedly smooth," says Jeff Kegley of NASA's Marshall Space Flight Center.

Right: The James Webb Space Telescope, an artist's concept. Credit: ESA. [Larger image]

To get ready for space, the 18 mirror segments that will ultimately form the Webb telescope’s huge primary mirror are trucked from pit stop to pit stop in tandem cross-country for careful processing and polishing. They visit seven different states, some several times.

During the long odyssey, every precaution is taken for their protection. How many years of bad luck would you have if you broke one of these mirrors?

"That's something we don't talk about," laughs Helen Cole, also of Marshall. "But seriously, we do have three spare segments, so no problem there."

Let's trace a mirror segment's Earthly journey from rough start to "wickedly smooth," and finally to union with its 17 siblings to form a 6.5 meter (21 ½ foot) wide whole with a total area of 25 square-meters (almost 30 square yards).

The story begins in a Utah beryllium mine. Beryllium is one of the lightest of all metals, and the "stuff" of the telescope's mirrors.

Above: The making of the JWST mirrors begins here in a Utah Beryllium mine. Photo credit: Brush Wellman, Inc., Beryllium Products division. [Larger image]

Technicians in Ohio sift and purify the gritty beryllium powder from Utah into an extremely uniform optical grade especially for the Webb mirror. Then they pour the powder in a big, flat can, apply heat and pressure, and pump out the residual gas to create a large slab called a mirror billet. They bathe the billet in acid to burn off any stainless steel stuck to the billet when the can is removed. Next they split the billet in half Oreo-cookie-style to form two mirror blanks (no cream!). These mirror blanks are the largest ever produced in beryllium.

Workers in Alabama machine the back of each blank into a honeycomb structure to make the blanks lighter without reducing stiffness. The machined ribs are less than 1 millimeter thick -- almost paper cut thin!

"This precision machining/etching removes 92 percent of a blank's mass," says Lee Feinberg of the Goddard Space Flight Center. "Mass is critical in launching space missions."

Next, a California company grinds and polishes the segments to a very smooth and exact shape and optically tests them at room temperature.

Above: Key stops in the long journey of the JWST. Not shown: space. [Larger image]

But the Webb telescope will not operate in room temperature. Not only will this telescope mirror be "wickedly smooth," it will also be wickedly cold in space. Because it is an infrared telescope, the JWST is designed to pick up the heat of faint, awesomely distant stars and galaxies. To do that it has to be kept extremely cold. It will operate in space at about -238 deg Celsius (-396 deg Fahrenheit, 35K).

"The extreme cold may cause the telescope's structures and mirrors to change shape, so testing has to be done here on Earth under similar, hyper-cold conditions," says Cole.

This super-cold testing is done in Alabama. The Marshall Space Flight Center's X-ray & Cryogenic Facility has a vacuum chamber that can simulate the incredibly cold conditions of space. Testing in this chamber reveals even the tiniest distortions that happen to the mirror segments in the cold. The tests provide precise data that specifies the exact repolishing to be done to compensate ahead of time for distortions likely to occur in space.

Above: (Left) A prototype JWST beryllium mirror segment at Tinsley Labs in Richmond, California; (Right) Mirror testing under space-cold conditions at the Marshall Space Flight Center's X-ray & Cryogenic Facility. [Larger images: #1, #2]

Once the mirror segments are polished to precision, gold is evaporated over them, forming a very thin coating on the smooth mirror surface.

"This gold coating is highly reflective over all the wavelengths of the Webb telescope, from visible to mid-infrared," says Feinberg.

All 18 segments finally meet at Goddard Space Flight Center. Here, they're mounted on structures that will ultimately hold them in place and let them perform as if they were part of a single giant hexagonal mirror. (The mirror structure will be folded with its shield origami style when it's time to fit in a rocket.) Next the telescope is fully assembled and attached to the instrument module, and the whole kit and caboodle is acoustic and vibration tested.

Final cryogenic testing takes place at Johnson Space Center, in the same vacuum chamber that tested the Apollo lunar lander.

The telescope is integrated with the spacecraft and sunshield at Northrop Grumman in California. It will lift-off from Kourou, French Guiana, on an Ariane 5 rocket.

Are we there yet? Almost. Only 930,000 more miles to go....

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Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA

Return of the Leonids

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Dec. 4, 2008: Astronomers from Caltech and NASA say a strong shower of Leonid meteors is coming in 2009. Their prediction follows an outburst on Nov. 17, 2008, that broke several years of "Leonid quiet" and heralds even more intense activity next November.

"On Nov. 17, 2009, we expect the Leonids to produce upwards of 500 meteors per hour," says Bill Cooke of the NASA Marshall Space Flight Center. "That's a very strong display."

Forecasters define a meteor storm as 1000 or more meteors per hour. That would make the 2009 Leonids "a half-storm," says Jeremie Vaubaillon of Caltech, who successfully predicted a related outburst just a few weeks ago.

Right: A composite, all-sky image of the 2008 Leonid outburst over Colorado. Credit: Chris Peterson, Cloudbait Observatory. [more]

On Nov. 17, 2008, Earth passed through a stream of debris from comet 55P/Tempel-Tuttle. The gritty, dusty debris stream was laid down by the Leonids' parent comet more than five hundred years ago in 1466. Almost no one expected the old stream to produce a very strong shower, but it did. Observers in Asia and Europe counted as many as 100 meteors per hour.

Vaubaillon predicted the crossing with one-hour precision. "I have a computer program that calculates the orbits of Leonid debris streams," he explains. "It does a good job anticipating encounters even with very old streams like this one."

Sign up for EXPRESS SCIENCE NEWS delivery The Nov. 17, 2008 outburst proved that the 1466 stream is rich in meteor-producing debris, setting the stage for an even better display in 2009.

On Nov. 17, 2009, Earth will pass through the 1466 stream again, but this time closer to the center. Based on the number of meteors observed in 2008, Vaubaillon can estimate the strength of the coming display: five hundred or more Leonids per hour during a few-hour peak centered on 21:43 UT.

"Our own independent model of the debris stream agrees," says Cooke. "We predict a sub-storm level outburst on Nov. 17, 2009, peaking sometime between 21:34 and 21:44 UT."

The timing favors observers in Asia, although Cooke won't rule out a nice show over North America when darkness falls hours after the peak. "I hope so," he says. "It's a long way to Mongolia."

Above: Meteor counts for the 2008 Leonid outburst compiled by members of the International Meteor Organization. [more]

Many readers will remember the great Leonid showers of 1998-2002. The best years (1999 and 2001) produced storms of up to 3000 Leonids per hour. The 2009 display won’t be so intense. Instead, if predictions are correct, next year's shower could resemble the 1998 Leonids, a "half-storm"-level event caused by a stream dating from 1333. That old stream turned out to be rich in nugget-sized debris that produced an abundance of fireballs. Many observers consider the 1998 Leonids to be the best they've ever seen.

Could 2009 be the same? Vaubaillon expects a similar number of meteors but fewer fireballs. If the models are correct, the 1466 stream in Earth’s path contains plenty of dust but not so many nuggets, thus reducing the fireball count. On the bright side, the Moon will be new next Nov. 17th so nothing will stand in the way of the shower reaching its full potential.

Mark your calendar and stay tuned for updates from Science@NASA.

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Author: Dr. Tony Phillips | Credit: Science@NASA

The potential for coral growth in the Caribbean region is dramatically changing due to ocean acidification.

High resolution (Credit: NOAA)

A new study, which confirms significant ocean acidification across much of the Caribbean and Gulf of Mexico, reports strong natural variations in ocean chemistry in some parts of the Caribbean that could affect the way reefs respond to future ocean acidification. Such short-term variability has often been underappreciated and may prove an important consideration when predicting the long-term impacts of ocean acidification to coral reefs. 

Conducted by scientists from NOAA and the University of Miami's Rosenstiel School of Marine and Atmospheric Science, the study was published in the Oct. 31, 2008 issue of the Journal of Geophysical Research – Oceans.

Previous NOAA studies have shown that a quarter of the carbon dioxide that humans place in the atmosphere each year ends up being dissolved into the ocean. The result is the ocean becomes more acidic, making it harder for corals, clams, oysters, and other marine life to build their skeletons or shells. A number of recent studies demonstrate that ocean acidification is likely to harm coral reefs by slowing coral growth and making reefs more vulnerable to erosion and storms.

In the new study, NOAA scientists used four years of ocean chemistry measurements taken aboard the Royal Caribbean Cruise Line ship Explorer of the Seas together with daily satellite observations to estimate changes in ocean chemistry over the past two decades in the Caribbean region. The resulting new ocean acidification tracking products are available online along with animations of the changes since 1988.

"Ocean acidification has become an important issue to coral reef managers and researchers,” said Tim Keeney, deputy assistant secretary for oceans and atmosphere and co-chair of the United States Coral Reef Task Force. “These new tools provide these communities with better information to guide future research. This is the first time that anyone has been able to track ocean acidification on a monthly basis."

The study supports other findings that ocean acidification is likely to reduce coral reef growth to critical levels before the end of this century unless humans significantly reduce carbon dioxide emissions. While ocean chemistry across the region is currently deemed adequate to support coral reefs, it is rapidly changing as atmospheric carbon dioxide levels rise.

“The study demonstrates a strong natural seasonal variability in ocean chemistry in waters around the Florida Keys that could have important consequences for how these reefs respond to future ocean acidification," says NOAA's Dwight Gledhill, Ph.D., lead author of the study.

C. Mark Eakin, Ph.D., coordinator of NOAA’s Coral Reef Watch, said “Organisms from highly variable environments are often better adapted to changes like we have seen in the last 20 years. The real question is how far corals can adapt and if this natural variability will be enough to protect them."

Co-authors of the paper are Rik Wanninkhof, Ph. D., NOAA Research's Atlantic Oceanographic and Meteorological Laboratory, Frank J. Millero, Ph. D, University of Miami's Rosensteil School of Marine and Atmospheric Science, and Eakin, NOAA National Satellite and Information Service's Coral Reef Watch.

View of the Trouvadore’s keel, garboard and frames from starboard side.

High resolution (Credit: 2008: Search for the Slave Ship Trouvadore / NOAA)

Maritime archaeologists today announced they have recently identified the wreck of the historic slave ship Trouvadore off the coast of East Caicos in the Turks and Caicos Islands. NOAA’s Office of Ocean Exploration and Research significantly funded several years of archaeological research leading to the discovery by Don Keith and Toni Carrell, from Ships of Discovery, an underwater archaeology research institute.

The Spanish vessel Trouvadore was participating in the slave trade, outlawed in the British Indies, including the Turks and Caicos Islands. In 1841, after the vessel was grounded on a reef, Caicos authorities arrested the crew, and most of the 192 African survivors settled on Grand Turk Island.

Keith and Carrell believe the African survivors of the Trouvadore are the ancestors of a large portion of current residents in the Turks and Caicos Islands. For example, traditions on the Islands have a recognizable African origin. The Turks and Caicos National Museum is recording these traditions through oral histories and is educating the community about their ancestral history.

The hull remains of the so-called “Black Rock Wreck” were measured and compared to the dimensions of known shipwrecks off East Caicos.

High resolution (Credit: 2008: Search for the Slave Ship Trouvadore / NOAA)

“What makes a people different and distinct is their unique history,” said Keith, who has worked in the islands for 30 years. “The people of the Turks and Caicos have a direct line to this dramatic, historic event – it’s how so many of them ended up being there. We hope this discovery will encourage the people of the Turks and Caicos to protect and research their local history, especially the history that remains underwater.”

“Although the sinking of the Trouvadore was a major event on the Island, the story was lost to history over the following century and a half,” said Carrell. “After we uncovered records of the shipwreck several years ago, we were stunned to realize that Turks and Caicos residents had never heard of the shipwreck that brought their ancestors to the Island.”

In 2004, using historical accounts of where the Trouvadore went down, along with remote sensing and visual searches, archaeologists focused on a ship near a local landmark known as the Black Rock. Records showed the vessel had sunk at Breezy Point, approximately two miles from the Black Rock Wreck location.

This heavily concreted carronade is one of 10 located during the 2008 expedition.

High resolution (Credit: 2008: Search for the Slave Ship Trouvadore / NOAA)

“But with the wind blowing constantly from the east, and a current running from that direction, the ship would have drifted,” Keith said. “That could have happened after it was lightened by salvage, as well.” Keith and his team used careful measurements of the hull and after years of research to amass compelling circumstantial evidence, concluded in August that the Black Rock Wreck could only be the Trouvadore.

Keith and Carrell knew from the start it would be difficult to find artifacts to identify the ship. “People of these islands traditionally have used resources from sunken ships. There are houses built on Grand Turk from ship remains,” said Keith. “We knew the ship had been salvaged upon sinking, and we weren’t going to find a bell with ‘Trouvadore 1841’ on it.”

The archaeologists learned about the Trouvadore while tracing the current locations of artifacts from the Islands that were sold to museums in the U.S. and Europe over a hundred years ago. Examining records about “African idols” that were sold, they found the account of the Trouvadore wreck.

The position of two large wooden deadeyes helped to confirm the location of the master frame.

High resolution (Credit: 2008: Search for the Slave Ship Trouvadore / NOAA)

“It's rare and exciting to find a wreck of such importance that has been forgotten for so many years,” said Frank Cantelas, marine archaeologist for NOAA’s Office of Ocean Exploration and Research.  “By identifying the Trouvadore, Don and Toni have really made a contribution to history and given the Islands’ people a better sense of place.” 

Keith and his colleagues also discovered the wreck of the U.S. naval vessel Chippewa, lost in 1816. The researchers discovered a line of carronades, a unique type of cannon carried by the Chippewa, near the reef off Providenciales, which the vessel reportedly struck. The Chippewa and the Onkahye, sunk in 1848, were part of America’s efforts to stop the African slave trade and piracy by patrolling the Caribbean. Keith plans to continue work on the Chippewa wreck site and hopes to discover the Onkahye nearby.

The 2008 Atlantic Hurricane Season officially comes to a close on Sunday, marking the end of a season that produced a record number of consecutive storms to strike the United States and ranks as one of the more active seasons in the 64 years since comprehensive records began.

High resolution (Credit: NOAA)

A total of 16 named storms formed this season, based on an operational estimate by NOAA's National Hurricane Center. The storms included eight hurricanes, five of which were major hurricanes at Category 3 strength or higher. These numbers fall within the ranges predicted in NOAA’s pre- and mid-season outlooks issued in May and August. The August outlook called for 14 to 18 named storms, seven to 10 hurricanes and three to six major hurricanes. An average season has 11 named storms, six hurricanes and two major hurricanes.

“This year’s hurricane season continues the current active hurricane era and is the tenth season to produce above-normal activity in the past 14 years,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA's Climate Prediction Center.

Overall, the season is tied as the fourth most active in terms of named storms (16) and major hurricanes (five), and is tied as the fifth most active in terms of hurricanes (eight) since 1944, which was the first year aircraft missions flew into tropical storms and hurricanes.

For the first time on record, six consecutive tropical cyclones (Dolly, Edouard, Fay, Gustav, Hanna and Ike) made landfall on the U.S. mainland and a record three major hurricanes (Gustav, Ike and Paloma) struck Cuba. This is also the first Atlantic season to have a major hurricane (Category 3) form in five consecutive months (July: Bertha, August: Gustav, September: Ike, October: Omar, November: Paloma).

Bell attributes this year’s above-normal season to conditions that include:

• An ongoing multi-decadal signal. This combination of ocean and atmospheric conditions has spawned increased hurricane activity since 1995.
• Lingering La Niña effects. Although the La Niña that began in the Fall of 2007 ended in June, its influence of light wind shear lingered.
• Warmer tropical Atlantic Ocean temperatures. On average, the tropical Atlantic was about 1.0 degree Fahrenheit above normal during the peak of the season.

Download as Quicktime (Credit: NOAA)

NOAA's National Hurricane Center is conducting comprehensive post-event assessments of each named storm of the season. Some of the early noteworthy findings include:

• Bertha was a tropical cyclone for 17 days (July 3-20), making it the longest-lived July storm on record in the Atlantic Basin.
• Fay is the only storm on record to make landfall four times in the state of Florida, and to prompt tropical storm and hurricane watches and warnings for the state’s entire coastline (at various times during its August lifespan).
• Paloma, reaching Category 4 status with top winds of 145 mph, is the second strongest November hurricane on record behind Lenny in 1999 with top winds of 155 mph).

Much of the storm-specific information is based on operational estimates and some changes could be made during the review process that is underway.

“The information we’ll gain by assessing the events from the 2008 hurricane season will help us do an even better job in the future,” said Bill Read, director of NOAA's National Hurricane Center. “With this season behind us, it’s time to prepare for the one that lies ahead.”

NOAA will issue its initial 2009 Atlantic Hurricane Outlook in May, prior to the official start of the season on June 1.

Spectacular Conjunction

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This story ends with the best sky show of the year--a spectacular three-way conjunction of Venus, Jupiter and the crescent Moon.

It begins tonight with a sunset stroll.

At the end of the day, when the horizon is turning red and the zenith is cobalt-blue, step outside and look southwest. You'll see Venus and Jupiter beaming side-by-side through the twilight. Glittering Venus is absolutely brilliant and Jupiter is nearly as bright as Venus. Together, they're dynamite:

Above: Venus and Jupiter converging over Hawaii on Nov. 19, 2008. Photo credit and copyright: Stephen O'Meara. [Larger image]

Add another stick of TNT and voila!—it's tomorrow. Go outside at the same time and look again. You’ll be amazed at how much the Venus-Jupiter gap has closed. The two planets are converging, not in the slow motion typical of heavenly phenomena, but in a headlong rush—almost a full degree (two full Moon widths) per night. As the gap shrinks, the beauty increases.

Sign up for EXPRESS SCIENCE NEWS delivery On Nov. 29th (sky map) the two planets will be less than 3 degrees apart and you'll think to yourself "surely it can't get any better than this."

And then it will. On Nov. 30th (sky map) a slender 10% crescent Moon leaps up from the horizon to join the show. The delicate crescent hovering just below Venus-Jupiter will have cameras clicking around the world.

Dec. 1st (sky map) is the best night of all. The now-15% crescent Moon moves in closer to form an isosceles triangle with Venus and Jupiter as opposing vertices. The three brightest objects in the night sky will be gathered so tightly together, you can hide them all behind your thumb held at arm's length.

The celestial triangle will be visible from all parts of the world, even from light-polluted cities. People in New York and Hong Kong will see it just as clearly as astronomers watching from remote mountaintops. Only cloudy weather or a midnight sun (sorry Antarctica!) can spoil the show.

Although you can see the triangle with naked eyes--indeed, you can't miss it—a small telescope will make the evening even more enjoyable. In one quick triangular sweep, you can see the moons and cloud-belts of Jupiter, the gibbous phase of Venus (69% full), and craters and mountains on the Moon. It's a Grand Tour you won't soon forget.

Right: A sky map of the triple conjunction on Dec. 1, 2008. More maps: Nov. 24, 25, 26, 27, 28, 29, 30, Dec. 1 2008.

Finally, look up from the eyepiece and run your eyes across the Moon. Do you see a ghostly image of the full Moon inside the bright horns of the crescent? That's called "Earthshine" or sometimes "the da Vinci glow" because Leonardo da Vinci was the first person to explain it: Sunlight hits Earth and ricochets to the Moon, casting a sheen of light across the dark lunar terrain.

By itself, a crescent Moon with Earthshine is one of the loveliest sights in the heavens. Add Venus and Jupiter and … well ... it's time to stop reading and go mark your calendar:

Dec. 1st @ sunset: Sky show of the year!

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Author: Dr. Tony Phillips | Credit: Science@NASA