DaveMurray's Blog

*** THE FALL FORECAST IS ONLINE.  NO T.V. SPECIAL IN THE FALL...JUST ONLINE. SEPTEMBER...OCTOBER AND NOVEMBER OF 2008...THE WINTER FORECAST WILL BE OUT IN MID NOVEMBER:

CLICK HERE TO READ THE FALL 2008 FORECAST

I WILL BE OUT OF THE OFFICE FOR SEVERAL DAYS...BUT WILL CHECK IN FROM TIME TO TIME.

IDEAS FOR THE LAST WEEK OF AUGUST:

*** TEMPERATURES WILL BE A LITTLE WARMER THIS WEEK...NEAR TO ABOVE NORMAL...SOMETHING DIFFERENT TO END A VERY NON-AUGUST MONTH

*** LIMITED RAIN AND STORMS...BUT THAT IS RATHER TYPICAL FOR THIS TIME OF YEAR...AS WE GET READY TO ROLL INTO THE FALL SEASON

*** WATCH FOR THE TROPICS TO CONTINUE TO RAMP UP--"FAY" JUST A PREVIEW OF THINGS TO COME...THE NEXT FOUR WEEKS WILL BE VERY ACTIVE

STAR CHART INFO:

All week, little Mars closes in on Venus and Mercury, which are paired lower down. By the 31st they'll form this nice triangle. Sky & Telescope diagram

Comet Boattini 

THE COOL PIC OF THE DAY:

FOR THE WEATHER HISTORY ON THIS DATE...HEAD TO THIS SITE:

http://www.weatherforyou.com/history/

As always...enjoy the weather...Dave

"the best forecasters are not always certain where they are in the atmsophere...but they are always aware of their uncertainty"

Don't forget when your in your car you can get my forecast on:

KHITS 96

105.7 THE POINT

KSHE 95

SCIENCE "THINGS" TO THINK ABOUT

#1

The confirmation of Martian water ice by the Phoenix Mars Lander may hint at the planet's potential for supporting life - or at least human life.

So perhaps it's no surprise that he devotes his spare moments to tinkering with a device that can beam microwaves down to help extract underground water ice. "One of the chief advantages of microwaves is that it will penetrate the soil, and so would greatly minimize if not eliminate requirement to dig," Ethridge told SPACE.com. Eliminating the need to dig would also reduce the chance for dust to cause problems with astronauts and their equipment. Microwaves could also work better on the moon given its near-vacuum environment and super-insulating lunar dust. Ethridge worked with colleague Bill Kaukler, also at NASA Marshall, to run demonstration tests on simulated lunar permafrost. They found that they could remove 98 percent of water ice through sublimation, or converting the frozen water directly into a gas, and could also capture 99 percent of the extracted water.

NASA scientists have quietly developed technologies such as microwave beams for future explorers to extract water from the moon or Mars, even as the Phoenix team focuses on finding out more about the Martian climate and history of water. "If there is an outpost, there's a need for water, and we don't want to bring water from Earth," said Edwin Ethridge, a materials scientist at NASA's MarshallSpaceFlightCenter in Huntsville, Ala. Water could provide more than just an extraterrestrial drink: the right equipment could break down water for oxygen and even fuel for a human mission. That could lighten the load and cost of any future mission heading for the moon or Mars. Ethridge spends most of his time working on the Ares rockets slated to return NASA astronauts to the moon. #2

An ant becomes a dominant queen or a lowly worker is determined by both nature and nurture, it turns out. A new study found that an ant's social status in its colony depends both on its genetic inheritance and the food it eats when it is young. Researchers studied Florida harvester ants (Pogonomyrmex badius) to investigate what factors decide a particular ant's social caste. "Basically what we found is that things are more complicated than previously thought," said researcher Christopher R. Smith, a former graduate student at the University of Illinois at Urbana-Champaign and now a postdoctoral researcher at Arizona State University.

"Our study shows that there is a large genetic component to caste determination, but that there is also a very strong environmental component." The study, led by University of Illinois at Urbana-Champaign biologist Andrew Suarez, was detailed in the August issue of the journal American Naturalist. In P. badius societies there is only one social trajectory for males - they are produced about once a year and "do nothing but mate and die," Smith said.#3:

Tiny transmitters attached to Atlantic salmon are helping to solve a mystery about their lengthy and sometimes fatal ocean treks and why the fish's population numbers are dropping...Adult salmon are champion swimmers, often trekking more than 2,500 miles (4,000 km) from rivers to the ocean feeding grounds and back to these same rivers to reproduce. Once salmon hatchlings emerge from their eggs in freshwater rivers, they spend the first two to three years of their lives in that water before migrating to the ocean. However, for every, say, 140 salmon that reach the ocean, only one fish returns to the river, said Mike Stokesbury, director of research for the Ocean Tracking Network (OTN), headquartered at Dalhousie University in Nova Scotia

"They know the fish are dying in the ocean, but they don't know where." The transmitters showed that significant numbers of the fish are at least making it well into the sea, rather than dying as soon as they enter the ocean. About 30 percent of a tagged group migrated from a river in Maine at least 370 miles (600 km) in the ocean to a region off the coast of Halifax, Nova Scotia, on their way to feeding grounds off of Greenland. "Salmon are an iconic fish, but they're becoming endangered and people want to know what's happening to the population," Stokesbury said. "This is the first step to finding out where in the ocean the salmon are dying and what's causing the decline."

 #4: Hordes of mountain pine beetles are decimating British Columbian forests. Rising temperatures due to global warming have boosted the beetles' numbers by increasing their reproductive rate and reducing their winter die-off.

That's a lot of dead trees, which release CO2 as they decompose. Meanwhile, there are fewer healthily growing trees left to absorb the greenhouse gas through photosynthesis. Using a computer model, Kurz's team calculated that by 2020, the beetles will have killed so much forest that their net effect will be the equivalent of five years of CO2 emissions by all the cars and trucks of Canada. Kurz and his team are the first to account for large-scale insect outbreaks in an analysis of forest carbon balances - and to show the positive feedback loop between climate change and insect pests. They're unlikely to be the last, however, given the risk of more boreal forests falling prey to warmth-loving insects. The research was detailed in the journal Nature.

Now, in a perverse twist, a new study shows that in a few years, the pests will have turned the once climate-friendly forests into net emitters of carbon dioxide (CO2). Since 2000, the beetles have killed off more than 32 million acres of forest, according to Werner A. Kurz and a team of scientists from the Canadian Forest Service. Kurz and colleagues say the current outbreak is an order of magnitude larger than any previous mountain-pine-beetle explosion, and they predict it will take another twelve years or so to taper off.

#5 The impact of global warming in the Arctic may differ from the predictions of computer models of the region, according to a pair of Penn State biologists. The team - which includes Eric Post, a PennState associate professor of biology, and Christian Pederson, a PennState graduate student - has shown that grazing animals will play a key role in reducing the anticipated expansion of shrub growth in the region, thus limiting their predicted and beneficial carbon-absorbing effect. The team's results will be published in the online Early Edition of the journal Proceedings of the National Academy of Sciences. Most computer models indicate that shrubs will thrive and spread as a result of global warming. And because shrubs have an increased ability over grasses and other small plants to absorb the greenhouse gas carbon dioxide, many scientists believe that shrubs will absorb some of this carbon dioxide and, thereby, lessen the impact of climate change.

While Post and Pederson agree that global warming will promote the growth of shrubs, they argue that grazing by muskoxen and caribou will reduce the carbon-mitigating benefit of the plants. "If you imagine a chessboard on which the dark squares are shrubs and the light squares are grasses, warming alone would tend to increase the size of the dark squares until the chess board is completely filled in," said Post. "Our experiment suggests that herbivores, like caribou and muskoxen, will slow this process, inhibit it, or perhaps even increase the size of the white squares on the chessboard."

#6: Mayor Michael Bloomberg has proposed a renewable energy program for New York City that would include placing windmills on city bridges, solar panels on skyscrapers, and the use of tidal, geothermal and nuclear energy. Bloomberg unveiled the outlines of his plan late Tuesday at a major clean energy summit in Las Vegas organized by the University of Nevada. "Just five years ago last week - on August 14th, 2003 - this country got an object lesson in how big a gamble we're taking with our future if we don't change course," said Bloomberg, referring to the giant blackout that cut off power for 50 million people across the northeastern United States and Canada. Hundreds of people were rescued from high-rise elevators, and thousands more were rescued from stalled trains in the city's subway system. "We learned that this time, the enemy was us and our failure to take care of our infrastructure," he said.

"The world's greatest nation was shown to have a power grid that was seriously over-strained and out-of-date." Bloomberg said he is determined to keep the city's energy usage at or near its current level even as the population grows. But the city has to increase production of clean energy, he said. "I believe that we've got to be willing to do what some other nations - such as France - have already done, and increase our capacity of safe and clean nuclear-generated power," he said. Clean energy projects could also "draw power from the tides of the Hudson and EastRivers - something we're already doing on a pilot basis," he said. Bloomberg proposed increasing rooftop solar power production, "which we've estimated could meet nearly 20 percent of the city's need for electricity."

#7: Penguin guano isn't usually considered an environmental hazard. Yet, according to new research, it is the main source of arsenic accumulation in Antarctic soil. Zhouqing Xie of the Institute of Polar Environment at the University of Science and Technology of China and colleagues looked at how much arsenic was found in the droppings of three bird species and two seal species that live on ArdleyIsland, off the Antarctic peninsular. The droppings of the gentoo penguin contained far more than those of the other species - nearly twice as much as the droppings of the southern giant petrel and up to three times more than the local seals. What's more, sediments from another Antarctic island that has no resident penguins but has a similar geology contained half the levels of arsenic compared with sediment sampled on ArdleyIsland.

So Xie's team tried to find out how arsenic levels change with the number of penguins in the area. They took a 34 centimetre mud core from the bottom of a lake on ArdleyIsland. This allowed them to measure how arsenic levels have fluctuated over the past 1,800 years and also to estimate how the local penguin population changed: a study published in 2000 (Nature) showed that penguin droppings alter the geochemical composition of lake sediments. Xie found that changes in the local penguin population were followed by changes in the arsenic levels in the lake. More penguins means more arsenic. Arsenic is an environmental contaminant that is naturally present. It is there in the water, which is absorbed by krill and then accumulates in the food chain, passing to predators such as penguins.

#8: Glider pilots harness upward-moving thermal air currents to keep them aloft for hours, while soaring birds use them to save energy. Uncrewed aerial vehicles may soon borrow the same technique to save precious fuel, using software that identifies regions of rising air. "It could increase the vehicles' endurance during surveillance missions," says Rhys Watkin of Roke Manor Research in Hampshire, UK, a member of the team that developed the system. To seek out nearby thermal currents, the software first analyses video of the sky taken by an on-board camera. It searches for the telltale grey, dome-shaped clouds that are formed by rapidly rising hot air. The system combines this with real-time weather forecasts and computer simulations of air flow across the local terrain to predict the locations of further thermal currents.

The team also fed the software information from anecdotal reports by expert gliders, highlighting areas of rising air in specific locations and in various weather conditions. During a mission, the software uses all of this data, together with the aircraft's GPS coordinates, to plan a route that passes through as many thermals as possible. So far, the system has only been used to suggest the path for a glider pilot to follow, but the team is developing software to enable an autonomous vehicle to fly solo. In the future, Watkin hopes to add further software that will analyse maps of the local area and estimate how well ground surfaces emit heat, which also helps predict the location of thermals.

#9: A man-sized grouper that trolls the tropical waters of the Eastern Pacific Ocean for octopuses and crabs has been identified as a new fish species after genetic tests. Called the goliath grouper, the fish can grow to six feet (1.8 meters) in length and weigh a whopping 1,000 pounds (454 kg). Until now, scientists had grouped this species with an identical looking fish (also called the goliath grouper, or Epinephelus itajara) living in the Atlantic Ocean. "For more than a century, ichthyologists have thought that Pacific and Atlantic goliath grouper were the same species," said lead researcher Matthew Craig of the Hawaii Institute of Marine Biology, "and the argument was settled before the widespread use of genetic techniques." Once upon a time, about 3.5 million years ago - before the Caribbean and the Pacific were separated by present-day Panama - they were, in fact, the same species.

Now, DNA tests have revealed the two populations have distinct genes, indicating they likely evolved into two separate species after their ocean homes were divided by Central America. Scientists disagree about how to define the term "species" and what separates species from one another biologically, though some say that a species is a group that can mate with one another and produce offspring that are not sterile. However, this biological definition doesn't always hold up, for instance, with coyotes and wolves (considered separate species), which can successfully produce fertile offspring. In this study, the scientists relied on differences in the fishes' genetic codes to establish the separate grouper species.

 

NOAA Maritime Archaeologists Discover Shipwreck of British Whaling Ship Gledstanes that Sank off Kure Atoll in 1837  

NOAA archaeologist measures the bore to a small cannon on the Gledstanes.

High resolution (Credit: NOAA)

A team of maritime heritage archaeologists from NOAA’s National Marine Sanctuaries have discovered the shipwreck remains of the 1837 British whaling ship Gledstanes. The shipwreck was foundoff Kure Atoll within the Papahanaumokuakea Marine National Monument during a month-long expedition to discover and document shipwrecks in monument waters.

At the end of the first exploratory dive of the day, the NOAA dive team discovered a pile of iron ballast and some chain. The ballast led to a trail into the dramatic topography of the reef where more artifacts were found scattered, including four massive anchors, iron ballast, cannons and cannon balls, a trypot.

“For years I have been coming up to Kure Atoll in hopes of searching for this particular shipwreck, but in the past we have been deterred by the weather and unworkable conditions,” said Kelly Gleason, NOAA archaeologist for the Monument and mission leader. “This year, the Gledstanes was revealed to us, and we couldn’t be more thrilled with the opportunity to share this wreck site and its story with the public.”

"The story of the Gledstanes and her survivors is limited, but adds to the important legacy of shipwreck survival stories at Kure Atoll,” said Hans VanTilburg, maritime heritage coordinator for NOAA's National Marine Sanctuaries' Pacific Islands Region. After the loss of their ship due to extremely rough seas, the crew launched the ship’s small boats and made for the closest dry land — the small sandy island at Kure Atoll named Ocean Island. In a short time, the Gledstanes broke apart in the heavy surf. The crew salvaged what they could from their destroyed ship and set about fashioning a 38-foot vessel called the Deliverance.

One of the four large anchors found at the wreck of the Gledstanes.

High resolution (Credit: NOAA)

The Gledstanes is the fourth whaling ship, and one of the oldest ships, discovered thus far in the Papahanaumokuakea Marine National Monument, shedding further light on the major significance of 19th-century whaling heritage in this region.

The researchers aboard the NOAA ship Hi‘ialakai will also make stops at French Frigate Shoals, Pearl and Hermes Atoll and Midway Atoll. The public can follow this month-long mission on the monument’s Web site.

Papahanaumokuakea Marine National Monument is administered jointly by three co-trustees — the Department of Commerce, Department of the Interior and the State of Hawai‘i — and represents a cooperative conservation approach to protecting the entire ecosystem. Co-trustee agencies in cooperation with the Office of Hawaiian Affairs manage the monument through the Monument Management Board. The Monument area includes the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve, Midway Atoll National Wildlife Refuge/Battle of Midway National Memorial, Hawaiian Islands National Wildlife Refuge, Kure Atoll Wildlife Sanctuary, and Northwestern Hawaiian Islands State Marine Refuge.

Ocean “Dead Zones” Increasing: 400 Oxygen-Deprived Areas Now Exist by Matthew McDermott, Brooklyn, NY on 08.15.08

image: NASA

Every year the topic of the dead zone in the Gulf of Mexico seems to pop up on TreeHugger—most recently in a report which links expanded corn production to the increasing size of the zone. New research shows that it’s not just in the Gulf that ocean dead zones are expanding but throughout the world.

Dead Zones Have Doubled Every 10 Years Since 1960s
According to the study, the number of marine dead zones—areas which are periodically or permanently starved of oxygen—has doubled every 10 years since the 1960s, with those along coastlines increasing in size and intensity. Currently there are about 400 coastal areas, with a combined area larger than the size of Oregon, with such poor water quality, with so little oxygen that only microbes can survive in it. Fish and crustaceans must flee the area or die.

Map showing partial number of current marine dead zones: Dr Robert Diaz/NASA

Fertilizer Run-Off, Sewage Worsen the Problem
The reason for the increase? The predictable culprit of human activity.

The New York Times describes what is happening:

Nitrogen from agricultural runoff and sewage stimulates the growth of photosynthetic plankton on the surface of coastal waters. As the organisms decay and sink to the bottom, they are decomposed by microbes that consume large amounts of dissolved oxygen. Most animals that live at the bottom of the coastal ocean cannot survive as oxygen levels drop.

 

image: US DEP

Stop the Runoff and the Dead Zones Could Recover
And steps that can be done the address the problem:

Robert W. Howarth, a professor of ecology and environmental biology at Cornell, said that methods to reduce nitrogen-rich runoff exist, including planting winter rye or winter wheat in cornfields during the off-season so the spring rains do not cause the chemicals to leach into waterways. [TH note: You could also decrease the amount of fertilizer used...]

 

Nevertheless, most experts agree that the changes needed to reverse the trend are dramatic. For example, scientists estimate that cutting the Gulf of Mexico’s dead zone by a third would require a 45 percent decrease in nitrogen-rich runoff from the Mississippi River watershed, which extends into the croplands of the upper midwest.

 

Want to know more? NASA has a pretty good overview of the issue of marine dead zones.

via :: The New York Times

The Realm of Earthworms: NASA Gets Down to the Nitty-Gritty

08.15.2008

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August 15, 2008: When you hear the word "NASA," do visions of rocket ships dance in your head?

Well think again. From now on, it's "earthworms."

That's right. Using space technology, NASA is now studying the realm of earthworms, millipedes, and springtails -- the soil beneath your feet -- with a project called OMEGA (Observing Microwave Emissions for Geophysical Applications).

Right: A subterranean cross-section of Alabama soil. Credit: USDA. [more]

Why would an agency whose cosmic vision knows no bounds care about the nitty-gritty crawling-grounds of lowly critters? Because NASA recognizes the vital role this "underworld" plays in our lives on Earth. For instance, if forecasters don't know how damp or dry the soil is, they can't accurately predict the weather.

"OMEGA soil moisture data will help us build better weather models," says NASA scientist Chip Laymon, principal investigator for the OMEGA project at the National Space Science and Technology Center in Huntsville, Alabama. "Better models mean better forecasts."

Sign up for EXPRESS SCIENCE NEWS delivery But there's more. According to Laymon, this research could help forecasters predict flash floods, land-slides and drought. OMEGA could also help farmers plan crop planting, make important decisions about irrigation, and predict crop yields.

How will OMEGA scientists gather the soil moisture data? "We use a microwave radiometer," says Laymon. Ordinary soil naturally emits a small amount of low-energy microwave radiation; all warm objects do. "By analyzing those microwaves we can tell how much moisture is in the soil."

The name of the instrument is MAPIR, short for Marshall Airborne Polarimetric Imaging Radiometer, and it's about to fly on its first mission onboard a NASA P-3 aircraft. "Our instrument has to be ready to install on the P-3 by Sept. 15," says Laymon. "We'll then fly missions over the Delmarva Peninsula between Oct. 1 and Oct. 14."

The Delmarva Peninsula, a 180 mile x 60 mile area of land on the east coast of the United States bounded by the Chesapeake Bay and the Atlantic Ocean, is a good place for MAPIR's maiden flight. Two-thirds of the peninsula is agricultural and one-third forested, so there is a variety of terrain to sample. Moreover, the USDA Agricultural Research Service has already been studying the area and they have set up their own moisture sampling stations. These can provide valuable "ground truth" comparisons for MAPIR's airborne data.

Above: OMEGA's microwave soil moisture sensor, MAPIR, will take its maiden flight onboard a NASA P-3 aircraft like this one. Photo credit: Stephen Ausmus, USDA-ARS

MAPIR's berth on the P-3 was an unexpected development. "Another mission slated to fly on the P-3 scrubbed, and a slot suddenly opened for us," says Laymon. "We've really had to accelerate our schedule for developing MAPIR. The intensity of the schedule is enormous -- trying to refocus and prepare for airworthiness reviews and other milestones. The team has worked tirelessly and we have many more long days to come."

The ultimate goal is three tiers of observation: OMEGA instruments on a truck and a plane, and a similar instrument built by NASA's Jet Propulsion Laboratory, on a satellite. Each sensor will tell the story of soil moisture from its own unique perspective. The truck, with its own huge microwave antenna, is almost ready. The satellite will most likely be in the form of the 2013 Soil Moisture Active Passive, or SMAP, space mission led by JPL. After the P-3 test-flight, OMEGA's regular plane will be a Polish-built Antonov aircraft, a big beefy biplane housed at a local airfield, affectionately known to the team members as "the flying tractor."

Right: The "Flying Tractor" awaits MAPIR in an Alabama air field.

"With this aircraft, we'll be able to do a lot of research locally. I expect 'the flying tractor' to be airborne before the end of the year," says Laymon.

Meanwhile, the rush to prepare for the upcoming P-3 flights has strained OMEGA researchers to the max. What's the hardest part? "Oh, probably the hallucinations from stress and lack of sleep," grins Laymon. No matter how hard he tries, he can't stop thinking about flying tractors and a universe of earthworms.

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

A Flash of Insight: LCROSS Mission Update

08.11.2008

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There are places on the Moon where the sun hasn't shined for millions of years. Dark polar craters too deep for sunlight to penetrate are luna incognita, the realm of the unknown, and in their inky depths, researchers believe, may lie a treasure of great value.

NASA is about to light one up.

Sometime between May and August 2009, depending on launch dates, the booster stage for NASA's LCROSS probe will deliberately crash into a permanently-shadowed lunar crater at 9,000 km/hr, producing an explosion equivalent to about 2,000 pounds of TNT (6.5 billion joules). The blast will jettison material out of the crater into broad daylight where astronomers can search the debris for signs of lunar water.

Water is the treasure. NASA plans to send people back to the Moon by 2020 and eventually set up a lunar outpost. Water would be an invaluable resource for astronauts living and working on the Moon. Not only could people drink it, but water could be used to grow plants for food, or it could be split into hydrogen for rocket fuel and oxygen to replenish the outpost's air. It even could shield astronauts from dangerous space radiation.

Hence the kamikaze mission, called the Lunar CRater Observation and Sensing Satellite (LCROSS), to search for H₂O on the Moon. "If LCROSS's booster stage hits a patch of lunar regolith that contains at least 0.5 percent water ice, water should be detectable in the plume of ejecta," explains Anthony Colaprete, principal investigator for LCROSS at NASA's Ames Research Center.

Right: The LCROSS booster stage hurtles toward the Moon as the mission's robotic satellite looks on. [more]

The other half of the LCROSS mission, a robotic satellite, will observe the impact and then itself crash into the Moon 4 minutes later. Most of the Moon is bone dry, of course. With virtually no atmosphere and 300° temperature swings between night and day, most of the Moon's surface is a hostile place for water. But there are a few cold, dark places where frozen water could stay put. At the lunar poles, the sun is always low on the horizon, so some crater ridges cast shadows that keep parts of the crater floors in perpetual darkness. Temperatures in the inky black shadows hover around 40° above absolute zero (-233° Celsius), cold enough for water ice to survive indefinitely.

"There's tantalizing evidence that water might be there," Colaprete says. A lunar orbiter called Clementine detected hints of water ice in some of these craters in 1994 and so did the 1999 Lunar Prospector mission, but unfortunately the data were not conclusive.

That's where LCROSS comes in. Ice blasted into the sunlight by the impact would vaporize. Ultraviolet light from the sun would then split the H₂O molecules into H and OH. Mission planners hope LCROSS's sensors will detect the fingerprint of H₂0 in near-infrared light and also a characteristic wavelength emitted by OH at 308 nanometers.

Above: The "life cycle" of LCROSS's impact plume. Click on the image to view a larger diagram and more information.

Currently, Colaprete's team is searching for the best impact sites inside various shadowed craters. "The first and most important criterion is that we think the impact area will be productive from an ejecta standpoint," Colaprete explains. "If we don't get ejecta into sunlight, it wouldn't matter if we hit an iceberg because we would never know it." For example, if the impact site is close to a high crater wall, the ejecta would have to travel far to get out of the wall's shadow and reach the sunlight above. And if the impactor hits a steep slope in the bottom of a shadowed crater, much of the ejecta would blast out sideways instead of upward toward the sunlight. So a good site would be relatively flat-bottomed — less than about 15° of slope — with a fluffy regolith free of large boulders or rubble that would blunt the blow.

Colaprete says that, so far, one of the best sites appear to be in a 17 km-across unnamed crater just west of Peary crater (88.6° N, 33.0° E), near the Moon’s north pole. "We've gone through essentially every possible launch date and picked a crater [for each date]," he says.

Above: The Moon's north pole. Each of the yellow dots marks a crater with possibly permanent shadows. According to a 2003 study, as much as 7,500 km2 around the lunar north pole could lie in perpetual shadow. [more]

Choosing impact sites must also take another factor into account: visibility from Earth. Hundreds of amateur and professional astronomers will join the LCROSS robotic orbiter in watching the crash.

The explosion itself will probably be hidden by the walls of the target crater. Instead, what astronomers will look for is the impact plume. An expanding cone of ejecta will rise more than 6 kilometers above the lunar surface and spread outward for about 40 km in every direction. Glistening in the sunlight, the debris is expected to shine like a 6th to 8th magnitude star—invisible to the human eye but an easy target for backyard telescopes.

Colaprete's team will time the impact so that it happens while the Moon is high in the sky at night in Hawaii. There, LCROSS scientists will observe the ejecta plume with the powerful Infrared Telescope Facility. But astronomers on the west coast of the U.S. and in Japan could be able to see the impact as well, depending on the precise impact time. "It really is going to turn into an international event," Colaprete says. "Everyone's going to be training their eyes on the impact to observe it."

Stay tuned to Science@NASA to find out how amateur astronomers can collaborate with LCROSS scientists to help make this historic search for water on the Moon a smashing success.

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

With Southern California’s earthquake in the news, here are some interesting facts and figures:

•

Earthquakes can trigger other natural disasters: landslides, flash floods, fires, avalanches, and tsunamis.

•

Each year in the U.S., an average of six magnitude 6 or higher and 57 magnitude 5 or higher earthquakes occur.

•

The largest recorded U.S. earthquake was magnitude 9.2 in Prince William Sound, Alaska, on March 28, 1964.

•

1812 along the New Madrid Fault in Missouri. The quakes were felt throughout the Eastern US.

The most widely felt series of earthquakes in the lower-48 states took place for three months between 1811 and

•

could be more devastating because the shaking would affect a larger area than a comparable quake in the

Western U.S. would. Additionally, population density is high in the East, and many buildings are not built to

withstand an earthquake.

While earthquakes are more common in the Western US, studies indicate that a severe quake in the Eastern U.S.

The Earthquake-Weather Myth

There is a common belief that earthquakes occur more frequently during hot and dry weather. Actually, scientists have

never found a correlation between weather and earthquake activity. Because earthquakes originate miles below

ground, they are not affected by weather occurring at the Earth's surface.

According to the US Geological Survey, there are 26 urban areas in the US at risk for significant shakes:

AK: Anchorage

CA: Fresno, Los Angeles, Sacramento, Salinas, San Diego, San

Francisco, Santa Barbara, Stockton-Lodi

ID: Boise

IN: Evansville

MA: Boston

MO: St. Louis

NM: Albuquerque

NV: Las Vegas, Reno

NY: New York

OR: Eugene-Springfield, Portland

PR: San Juan

SC: Charleston

TN: Chattanooga-Knoxville, Memphis

UT: Provo-Orem, Salt Lake City

WA: Seattle

Protecting Yourself during an Earthquake

Inside:

you are and try to brace yourself. If you are in bed, stay there and protect yourself with a pillow. Stay away from

windows, and stay inside until the shaking stops. A common myth is that you should head for a doorway -- In most

homes, doorways are no stronger than other areas, and swinging doors can cause injury. Take cover under a

strong piece of furniture, instead.

When the shaking begins, drop to the ground, take cover, and hold on. If you are unable to drop, stay where

Outside:

Drop to the ground and stay still until the shaking stops.

Find a clear area away from buildings, trees, streetlights, power lines, and other structures that may fall.

In a Car:

Pull over to a clear area, stop, and remain in your car with your seatbelt on.

Image: USGS

Plasma Bullets Spark Northern Lights

07.24.2008

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July 24, 2008: Duck! Plasma bullets are zinging past Earth.

That's the conclusion of researchers studying data from NASA's five THEMIS spacecraft. The gigantic bullets, they say, are launched by explosions 1/3rd of the way to the Moon and when they hit Earth—wow. The impacts spark colorful outbursts of Northern Lights called "substorms."

Right: A substorm of Northern Lights photographed from the window of an airplane over Hudson Bay, Canada, on Feb 27, 2008. Credit: Jeff Hapeman. [more]

"We have discovered what makes the Northern Lights dance," declares UCLA physicist Vassilis Angelopoulos, principal investigator of the THEMIS mission. The findings appear online in the July 24 issue of Science Express and in print August 14 in the journal Science.

The THEMIS fleet was launched in February 2007 to unravel the mystery of substorms, which have long puzzled observers with their unpredictable eruptions of light and color. The spacecraft wouldn't merely observe substorms from afar; they would actually plunge into the tempest using onboard sensors to measure particles and fields. Mission scientists hoped this in situ approach would allow them to figure out what caused substorms--and they were right.

The discovery came on what began as a quiet day, Feb 26, 2008. Arctic skies were dark and Earth's magnetic field was still. High above the planet, the five THEMIS satellites had just arranged themselves in a line down the middle of Earth’s magnetotail—a million kilometer long tail of magnetism pulled into space by the action of the solar wind.

Sign up for EXPRESS SCIENCE NEWS delivery That's when the explosion occurred.

A little more than midway up the THEMIS line, magnetic fields erupted, "releasing about 1015 Joules of energy," says Angelopoulos. "For comparison, that's about as much energy as a magnitude 5 earthquake."

Although the explosion happened inside Earth's magnetic field, it was actually a release of energy from the sun. When the solar wind stretches Earth's magnetic field, it stores energy there, in much the same way energy is stored in a rubber band when you stretch it between thumb and forefinger. Bend your forefinger and—crack!—the rubber band snaps back on your thumb. Something similar happened inside the magnetotail on Feb. 26, 2008. Over-stretched magnetic fields snapped back, producing a powerful explosion. This process is called "magnetic reconnection" and it is thought to be common in stellar and planetary magnetic fields.

The blast launched two "plasma bullets," gigantic clouds of protons and electrons, one toward Earth and one away from Earth. The Earth-directed cloud crashed into the planet below, sparking vivid auroras observed by some 20 THEMIS ground stations in Canada and Alaska. The opposite cloud shot harmlessly into space, and may still be going for all researchers know.

Above: An artist's concept of the THEMIS satellites lined up inside Earth's magnetotail with an explosion between the 4th and 5th satellites. [Larger image]

The THEMIS satellites were perfectly positioned to catch the shot.

"We had bulls-eyes on our solar panels," says THEMIS project scientist David Sibeck of NASA's Goddard Space Flight Center. "Four of the satellites were hit by the Earth-directed cloud, while the opposite cloud hit the fifth satellite." Simple geometry pinpointed the site of the blast between the 4th and 5th satellite or "about 1/3rd of the way to the Moon."

No damage was done to the satellites. Plasma bullets are vast, gossamer structures less dense than the gentlest wisp of Earth's upper atmosphere. They whoosh past, allowing THEMIS instruments to sample the cloud’s internal particles and fields without truly buffeting the satellite.

This peaceful encounter on the small scale of a spacecraft, however, belies the energy deposited on the large scale of a planet. The bullet-shaped clouds are half as wide as Earth and 10 times as long, traveling hundreds of km/s. When such a bullet strikes the planet, brilliant auroras and geomagnetic storms ensue.

Right: A collection of ground-based All-Sky Imagers (ASI) captures the aurora brightening caused by a substorm. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio. [animation]

"For the first time, THEMIS has shown us the whole process in action—from magnetic reconnection to aurora borealis," says Sibeck. "We are finally solving the puzzle of substorms."

The THEMIS mission is scheduled to continue for more than another year, and during that time Angelopoulos expects to catch lots more substorms--"dozens of them," he says. "This will give us a chance to study plasma bullets in greater detail and learn how they can help us predict space weather."

"THEMIS is not finished making discoveries," believes Sibeck. "The best may be yet to come."

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

Northern Wildfire Smoke May Cast Shadow on Arctic Warming

NOAA satellite image, June 30, 2004, showing wildfire smoke blanketing Alaska.

High resolution (credit: NOAA)

The Arctic may get some temporary relief from global warming if the annual North American wildfire season intensifies, according to a new study by researchers at the University of Colorado and NOAA.

Smoke transported to the Arctic from northern forest fires may cool the surface for several weeks to months at a time, according to the most detailed analysis yet of how smoke influences the Arctic climate relative to the amount of snow and ice cover.

"Smoke in the atmosphere temporarily reduces the amount of solar radiation reaching the surface. This transitory effect could partly offset some of the warming caused by the buildup of greenhouse gases and other pollutants," said Robert Stone, an atmospheric scientist with the university and NOAA Cooperative Institute for Research in Environmental Sciences (CIRES) and lead author of the study, which appears this week in the Journal of Geophysical Research.

How much solar energy is prevented from reaching the surface depends on the smoke's opacity, the elevation of the sun above the horizon, and the brightness of the surface, according to the study.

Stone and his research colleagues analyzed the short-term climate impact of numerous wildfires that swept through Alaska and western Canada in 2004. That summer, fires burned a record 10,000 square miles of Alaska's interior and another 12,000 square miles in western Canada.

A NOAA climate observatory near Barrow, Alaska, provided the data for the study. Smoke observed at Barrow was so thick that at times visibility dropped to just over one mile. The aerosol optical depth (AOD), a measure of the total absorption and scattering of solar radiation by smoke particles, rose a hundredfold from typical summer values.

Smoke in the atmosphere tends to cool the snow-free tundra while warming the smoke layer itself, the authors found. Smoke has an even greater cooling effect over the darker, ice-free ocean and less over bright snow.

"The heating of the smoke layer and cooling of the surface can lead to increased atmospheric stability, which in turn may keep clouds from forming," said Stone. "We think that this influence of smoke aerosol on clouds further affects the balance of radiation reaching the surface in the Arctic."

Research observatories as far away as Greenland and the Svalbard archipelago north of Norway also recorded elevated AOD values over several weeks during the 2004 summer, suggesting that the climate footprint of the North American wildfires was far-reaching. Smoke from the same fires also was observed as far south as the Gulf of Mexico.

To conduct their analysis, Stone and colleagues looked at how a range of smoky conditions might change the amount of solar radiation reaching the Earth’s surface. Models showed that the cooling caused by future forest fires would depend on the severity of the fire season and on the geographic dispersion of smoke.

The authors cautioned, however, that the full climate impact of Arctic aerosols, including smoke particles, is still not entirely clear. For one thing, smoke particles captured within clouds or deposited on snow may change the brightness of these objects, further affecting the amount of solar radiation absorbed by the surface.

Also, aerosols such as smoke affect the absorption and scattering not only of solar radiation, but also of longwave or thermal radiation within the atmosphere. The impact of aerosols on longwave radiation, which dominates at night and during the long, dark winter season in the Arctic, has yet to be quantified.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

NASA works to improve short-term weather forecasts

07.18.2008

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July 18, 2008: Sometimes seconds count. If a furious, tornado-spitting thunderstorm was bearing down on your home town, a few moments might make all the difference in the world.

Will McCarty, a graduate student at the National Space Science and Technology Center, is working with data from NASA's Aqua satellite to improve short-term weather predictions--the kind that could help you dodge that thunderstorm.

Above: Severe weather over DeWitt, Michigan, on June 14, 2008. Photo credit and copyright: Daniel O'Malley.

Guided by his NASA mentor, Gary Jedlovec, McCarty has already learned how to improve 48-hour forecasts by 3 hours. "That may not sound like a big deal, but tell that to someone who escaped a weather disaster by the skin of their teeth," says McCarty.

They accomplished the improvement by entwining measurements from Aqua's Atmospheric Infrared Sounder (AIRS), into weather models. To understand how AIRS works its magic, let's first take a look at how forecasts are made:

Sign up for EXPRESS SCIENCE NEWS delivery Twice a day, all over the world, weather balloons measure temperature, wind, air pressure and humidity. These balloons sample the lowest 7 to 10 miles of Earth's atmosphere, where weather happens. More measurements are made by surface observing stations, aircraft, and weather radars. All these data form a "snapshot" of the weather over the land at one point in time, every 12 hours.

Next, the measurements are plugged into forecast models--computer-coded equations that describe the interactions among the weather-influencing variables mentioned above, plus others. A forecaster interprets the model output to make his local weather prediction.

Sometimes lives ride on this mundane sounding process.

"The better we make the model output, the more the forecaster can trust it and use it as a tool for forecasting, and the more accurate forecasts the public receives," says McCarty.

AIRS improves the model output by improving its input: Riding on NASA's Aqua spacecraft and viewing the atmosphere through nearly 2,400 different spectral channels, AIRS creates an accurate global 3-D map of atmospheric temperature, water vapor, clouds and greenhouse gases.

Right: Will McCarty of the National Space Science and Technology Center in Huntsville, Alabama. [more]

"AIRS has finer resolution than previous instruments, so it can make more detailed measurements," says McCarty. "This makes analyses sharper, which improves the forecasts based on them."

McCarty and Jedlovec are most interested in AIRS infra-red "radiances," i.e., measurements of thermal energy emitted by the Earth's surface and atmosphere. The researchers look at radiances because they provide large scale measurements of the temperature and water vapor patterns in the atmosphere.

"Radiance measurements, in general, allow the observation of many places, particularly over the oceans, that are sparsely measured directly by traditional means, if at all," explains McCarty. "AIRS gives us the best picture of the vertical temperature and moisture structures ever made from space."

AIRS' claim to fame, then, is its capacity to increase both the area of Earth's atmosphere measured and the detail of those measurements.

Above: A typical AIRS infra-red weather snapshot. This is typhoon Nakri, which Aqua flew over on May 28, 2008. [more]

What's the next step? "Dealing with clouds," says McCarty. "Infrared energy doesn't penetrate clouds well. When clouds are around, the instrument is really only seeing the tops of clouds."

When clouds are low, however, there's still some good data from the air above them because most of the atmosphere is still being measured. These data have been wasted up to now – thrown out in the bathwater along with all the other cloud-contaminated data.

McCarty is now working on an algorithm to identify which channels are truly useless and which are valid. His method will help identify what is good, useful data and increase the amount of data collected, making even better forecasts possible. He will soon plug his data into a forecast model to find out just how much better.

A 3-hour improvement may be just the beginning.

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

What's Wrong with the Sun? (Nothing)

07.11.2008

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Stop the presses! The sun is behaving normally.

So says NASA solar physicist David Hathaway. "There have been some reports lately that Solar Minimum is lasting longer than it should. That's not true. The ongoing lull in sunspot number is well within historic norms for the solar cycle."

This report, that there's nothing to report, is newsworthy because of a growing buzz in lay and academic circles that something is wrong with the sun. Sun Goes Longer Than Normal Without Producing Sunspots declared one recent press release. A careful look at the data, however, suggests otherwise.

But first, a status report: "The sun is now near the low point of its 11-year activity cycle," says Hathaway. "We call this 'Solar Minimum.' It is the period of quiet that separates one Solar Max from another."

Above: The solar cycle, 1995-2015. The "noisy" curve traces measured sunspot numbers; the smoothed curves are predictions. Credit: D. Hathaway/NASA/MSFC. [more]

During Solar Max, huge sunspots and intense solar flares are a daily occurance. Auroras appear in Florida. Radiation storms knock out satellites. Radio blackouts frustrate hams. The last such episode took place in the years around 2000-2001.

During Solar Minimum, the opposite occurs. Solar flares are almost non-existant while whole weeks go by without a single, tiny sunspot to break the monotony of the blank sun. This is what we are experiencing now.

Sign up for EXPRESS SCIENCE NEWS delivery Although minima are a normal aspect of the solar cycle, some observers are questioning the length of the ongoing minimum, now slogging through its 3rd year.

"It does seem like it's taking a long time," allows Hathaway, "but I think we're just forgetting how long a solar minimum can last." In the early 20th century there were periods of quiet lasting almost twice as long as the current spell. (See the end notes for an example.) Most researchers weren't even born then.

Hathaway has studied international sunspot counts stretching all the way back to 1749 and he offers these statistics: "The average period of a solar cycle is 131 months with a standard deviation of 14 months. Decaying solar cycle 23 (the one we are experiencing now) has so far lasted 142 months--well within the first standard deviation and thus not at all abnormal. The last available 13-month smoothed sunspot number was 5.70. This is bigger than 12 of the last 23 solar minimum values."

In summary, "the current minimum is not abnormally low or long."

The longest minimum on record, the Maunder Minimum of 1645-1715, lasted an incredible 70 years. Sunspots were rarely observed and the solar cycle seemed to have broken down completely. The period of quiet coincided with the Little Ice Age, a series of extraordinarily bitter winters in Earth's northern hemisphere. Many researchers are convinced that low solar activity, acting in concert with increased volcanism and possible changes in ocean current patterns, played a role in that 17th century cooling.

For reasons no one understands, the sunspot cycle revived itself in the early 18th century and has carried on since with the familiar 11-year period. Because solar physicists do not understand what triggered the Maunder Minimum or exactly how it influenced Earth's climate, they are always on the look-out for signs that it might be happening again.

The quiet of 2008 is not the second coming of the Maunder Minimum, believes Hathaway. "We have already observed a few sunspots from the next solar cycle," he says. (See Solar Cycle 24 Begins.) "This suggests the solar cycle is progressing normally."

What's next? Hathaway anticipates more spotless days1, maybe even hundreds, followed by a return to Solar Max conditions in the years around 2012.

Stay tuned to Science@NASA for updates.

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

NASA to Attempt Historic Solar Sail Deployment

 

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"Hold your hands out to the sun. What do you feel? Heat, of course. But there's pressure as well – though you've never noticed it, because it's so tiny. Over the area of your hands, it only comes to about a millionth of an ounce. But out in space, even a pressure as small as that can be important – for it's acting all the time, hour after hour, day after day. Unlike rocket fuel, it's free and unlimited. If we want to, we can use it; we can build sails to catch the radiation blowing from the sun."1

These words were spoken not by a NASA scientist but by a fictional character – John Merton – in Arthur C. Clarke's short story The Wind from the Sun. If all goes well, Merton's prophetic words are about to become fact.

NASA researchers, thinking "out of the box" (or maybe "out of the rocket") have long dreamed of the possibility of sailing among the planets with sails propelled by sunlight instead of by wind. Except in works of fiction, though, no one has yet successfully deployed such a sail anywhere beyond Earth.

Right: An artist's concept of a sailing ship and a solar sail.

"There's a first time for everything," says Edward "Sandy" Montgomery of NASA's Marshall Space Flight Center.

Montgomery's team and a team from Ames Research Center (led by Elwood Agasid) hope to make history this summer by deploying a solar sail called NanoSail-D. It will travel to space onboard a SpaceX Falcon 1 rocket, scheduled for launch from Omelek Island in the Pacific Ocean during a window extending from July 29th to August 6th (a back-up extends from August 29th to September 5th).

Sign up for EXPRESS SCIENCE NEWS delivery "NanoSail-D will be the first fully deployed solar sail in space, and the first spacecraft to use solar pressure as a primary means of attitude control or orbital maneuvering," says Montgomery, who is NanoSail-D's payload manager.

"We are always on the lookout for opportunities. Ames owns a slot on the Falcon 1 launch and asked us if we wanted to go along. We said, 'Yes!' We'll use the Poly Picosatellite Orbital Deployer, or P-POD, developed by the University of California Polytechnic Institute to deploy our sail."

A few years ago, the Planetary Society attempted a mission like NanoSail-D called Cosmos I, but the launch vehicle failed and destroyed the undeployed spacecraft. Montgomery and team believe that NanoSail-D, however, will unfurl four gossamer wings from its pod in the blackness of space like a butterfly from a cocoon: movie.

"The structure is made of aluminum and space-age plastic," says Montgomery. "The whole spacecraft weighs less than ten pounds. We carry it around in a special suitcase -- airplane carry-on luggage size." Fully opened, the kite-shaped sail spreads out to about 100 square feet of light-catching surface.

Above: The Huntsville-based NanoSail-D team stands with the fully deployed sail at ManTech SRS technologies on April 16, 2008, after the successful deployment test.

"A success would be huge for the future of space exploration," Montgomery believes.

Why so important? Solar sails could extend our reach as far as our dreams. Because there's no friction in space, once a solar sail starts moving, it can go on forever. Indeed, long after a rocket would run out of gas and begin to coast, a solar sailship could still be accelerating, achieving speeds much faster and covering distances far greater than any rocket. No rocket in existence could carry enough fuel to reach the outer solar system in as short a time. And like a marine sail, a solar sail could also bring you home. You could use the solar sail to tack your vessel, making it travel "against the wind," back to Earth.

"It's not so much about how far a sail will go compared to a rocket; the key is how fast," says Montgomery. "The Voyagers have escaped the solar system, and they were sent by rockets, but it's taken more than three decades to do it. A sail launched today would probably catch up with them in a single decade. Sails are slower to get started though. So, for example, between the Earth and the moon, rockets might be preferred for missions with a short timeline. It's a trip of days for rockets, but months for a solar sail. The rule of thumb, therefore, would be to use rockets for short hops and solar sails for the long hauls."

Right: University of Alabama research technician Doug Huie holds the future in his hands. Folded-up, NanoSail-D occupies a space no bigger than a bread box.

All of this may sound like speculation, but NanoSail-D could show that solar sails are truly feasible. And there's an added bonus to this technology demo:

"Currently, micro-satellites in orbit above a few hundred kilometers can stay in orbit for decades after completing their mission," explains Montgomery. "This creates an orbital debris collision risk for other spacecraft. NanoSail-D will demonstrate the feasibility of using a drag sail to decrease the time satellites clutter up Earth's orbit. Although our sail looks like a kite, it will act like a parachute (or like a drag sail) in the very thin upper atmosphere around Earth. It will slow the spacecraft and make it lose altitude, re-enter the Earth's atmosphere and burn off in a relatively short period of time. A drag sail is a lighter alternative to carrying a propulsion system to de-orbit a satellite."

And finally, the question everyone wants answered: What does D stand for?

"We chose the 'D' in the name, not because it came after models A, B, and C, but because it can stand for demonstrate, deploy, drag, and/or de-orbit," says Montgomery.

Soon, 'D' may stand for something new: "DID IT!"

Check Science@NASA post-launch and the meaning will be revealed.

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

Scientific Assessment Captures Effects of a Changing Climate on Extreme Weather Events in North America

High resolution (Credit: NOAA)

The U.S. Climate Change Science Program and the Subcommittee on Global Change Research today released a scientific assessment that provides the first comprehensive analysis of observed and projected changes in weather and climate extremes in North America and U.S. territories. The Intergovernmental Panel on Climate Change previously evaluated extreme weather and climate events on a global basis in this same context. However, there has not been a specific assessment across North America prior to this report.

Among the major findings reported in this assessment are that droughts, heavy downpours, excessive heat, and intense hurricanes are likely to become more commonplace as humans continue to increase the atmospheric concentrations of heat-trapping greenhouse gases.

The report is based on scientific evidence that a warming world will be accompanied by changes in the intensity, duration, frequency, and geographic extent of weather and climate extremes.

"This report addresses one of the most frequently asked questions about global warming: what will happen to weather and climate extremes? This synthesis and assessment product examines this question across North America and concludes that we are now witnessing and will increasingly experience more extreme weather and climate events," said report co-chair Tom Karl, Ph.D., director of NOAA’s National Climatic Data Center in Asheville, N.C.

High resolution (Credit: NOAA)

"We will continue to see some of the biggest impacts of global warming coming from changes in weather and climate extremes,” said report co-chair Gerry Meehl, Ph.D., of the National Center for Atmospheric Research in Boulder, Colo. "This report focuses for the first time on changes of extremes specifically over North America."

The full CCSP 3.3 report, Weather and Climate Extremes in a Changing Climate, and a summary FAQ brochure are available online.

Global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases, according to the report. Many types of extreme weather and climate event changes have been observed during this time period and continued changes are projected for this century. Specific future projections include:

• Abnormally hot days and nights, along with heat waves, are very likely to become more common. Cold nights are very likely to become less common.
• Sea ice extent is expected to continue to decrease and may even disappear in the Arctic Ocean in summer in coming decades.
• Precipitation, on average, is likely to be less frequent but more intense.
• Droughts are likely to become more frequent and severe in some regions.
• Hurricanes will likely have increased precipitation and wind.
• The strongest cold-season storms in the Atlantic and Pacific are likely to produce stronger winds and higher extreme wave heigh