NASA : Cloud Streets in the Bering Sea .- Calles de la nube en el mar de Bering

Hola amigos. A VUELO DE UN QUINDE EL BLOG., . hemos recibido de la Fundación Nacional de Ciencias de Los Estados Unidos, sobre una espectacular fotografía del Mar de Bering, que precisamente la toma da una idea como si fuesen calles de hielo, captada por  NASA's Aqua satellite: Aguas de hielo, viento, temperaturas frías y mar se combinaron para creadas formaciones de nubes dramáticas sobre el mar de Bering a finales de enero de 2015....

La tundra congelada de Rusia se encuentra en el noroeste de la imagen, y Alaska nevado se encuentra en el noreste. El hielo marino se extiende desde la tierra hasta bien entrado el Mar de Bering. Durante la brillante línea de nubes blancas agua oscura en de cerca, filas paralelas. Estas formaciones son conocidas como "calles de nubes".

Más información. lea usted abajo....

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Cloud Streets in the Bering Sea

Ice, wind, cold temperatures and ocean waters combined to created dramatic cloud formations over the Bering Sea in late January, 2015. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA's Aqua satellite passed over the region and captured this true-color image on Jan. 23.

The frozen tundra of Russia lies in the northwest of the image, and snow-covered Alaska lies in the northeast. Sea ice extends from the land well into the Bering Sea. Over the dark water bright white clouds line in up close, parallel rows. These formations are known as “cloud streets”.

Air blowing over the cold, snowy land and then over ice becomes both cold and dry. When the air then moves over relatively warmer and much moister water and lead to the development of parallel cylinders of spinning air. On the upper edge of these cylinders of air, where the air is rising, small clouds form. Where air is descending, the skies are clear. This clear/cloudy pattern, formed in parallel rows, gives the impression of streets.

The clouds begin over the sea ice, but they primarily hang over open ocean. The streets are neat and in tight rows closest to land, while further over the Bering Sea the pattern widens and begins to become more random. The rows of clouds are also not perfectly straight, but tend to curve. The strength and direction of the wind helps create these features: where the wind is strongest, nearest to shore, the clouds line up most neatly. The clouds align with the wind direction, so the direction of the streets gives strong clues to prevailing wind direction.

Image Credit: NASA/Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC

NASA

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com 

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nsf.gov - National Science Foundation - Seed dispersal study shows value of conservation corridors

Ecologists study how wind moves seeds through longleaf pines

Seeds and flowers of the wind-dispersed species Solidago odora, part of the corridor experiment. Credit and Larger Version

February 24, 2014

Field ecologists go to great lengths to get data. Radio collars and automatic video cameras are among their tools for documenting the natural world.

So when a group of ecologists set out to see how wind moves seeds through isolated patches of habitat carved into a longleaf pine plantation, they came up with a novel way of addressing this question. They twisted colored yarn to create mock seeds that would drift with the wind much like native seeds.

The scientists discovered that both wind and the corridors between the patches of habitat matter to seed dispersal in the longleaf pine forest.

Their experimental "seeds" were dusted with fluorescent powder and inserted into custom-made boxes mounted on poles, then released as the scientists monitored local wind conditions.

That night, the field crew returned for a black-light treasure hunt, locating more than 80 percent of the fake seeds, which glowed under the ultraviolet light.

The paths of these glowing seeds were matched with output from a computer model to produce the first accurate picture of how wind moves seeds through corridors linking two patches of habitat.

The study results are published in a paper in this week's issue of the journal Proceedings of the National Academy of Sciences (PNAS).

Conservation biologists have long discussed building conservation corridors to link isolated patches of protected land.

"Understanding the conservation impact of corridors is at the cutting edge of conservation," says lead paper author Ellen Damschen, a zoologist at the University of Wisconsin-Madison.

Corridors are designed to improve conditions for uncommon native species living in separated habitats.

Small populations in these "islands" of habitat may be killed by storms or disease. They may lack genetic diversity and be prone to inbreeding. And they may be unable to reach new habitat.

"It makes intuitive sense that these connections could foster genetic and biological diversity," says Damschen. "But there has been little scientific evidence for if and how they work."

Most of the studies have involved animals, she adds, even though plants provide the basic energy and structure to land ecosystems.

Wind matters for the movement of seeds and whole organisms, Damschen says. "In many open habitats, more than one-third of plants are wind dispersed, but there are also insects, spiders, pathogens and fungi that move on the wind."

The experiment, supported by the National Science Foundation (NSF) and the U.S. Forest Service, began in 2000 with the creation of eight groups of patches at the Savannah River Site, a large holding of the U.S. Department of Energy. Each set of patches was built at a different orientation to prevailing winds.

"Relatively few researchers have investigated the effects of habitat configuration on wind-dispersed species," says Betsy Von Holle, a program director in NSF's Division of Environmental Biology, which funded the research. "This study demonstrates that influences on wind-dispersed species are more complex than previously thought."

A research group of meteorologists and ecologists found that corridors increased the movement of wind and of their glowing artificial seeds, echoing the results of a computer model developed by Gil Bohrer at The Ohio State University, a paper co-author.

And when Damschen and colleagues counted newly dispersed plants over the 12-year experiment, they found that a corridor linking two patches of land indeed promotes the diversity of plants dispersed by wind - especially if the corridor is oriented roughly parallel to the prevailing winds.

Both the data and the model showed that wind speeds up in certain areas of the patches, and that a strong vertical air movement is present.

"Uplift is important because the wind tends to be faster higher above the ground," Damschen says, "and uplift can lead to long-distance dispersal, which is significant for moving plants around the landscape."

That's why the study matters for conservation biology, Damschen says.

"We predicted that corridors in line with the dominant winds would move more species, and this is what we found. Wind alignment matters for species diversity in conservation areas."

The results are especially relevant to threatened Midwestern ecosystems like grasslands, prairies and savannas, where big bluestem and milkweed are two of many native plants that loft their seeds on the wind.

"In conservation science, it is often assumed that wind-dispersed seeds can go everywhere, but that's not true," Damschen says.

"Wind direction, and the shape of the habitat, control where these seeds go.

"While this adds another factor to consider in management of natural areas, the information is on the table so we can make better decisions about how to achieve management goals."

Other co-authors of the paper are: Dirk Baker of the University of Wisconsin-Madison; Ran Nathan of The Hebrew University of Jerusalem; John Orrock of the University of Wisconsin-Madison; Jay Turner of Washington University in St. Louis; Lars Brudvig of Michigan State University; Nick Haddad of North Carolina State University; Doug Levey of the University of Florida, Gainesville; and Joshua Tewksbury of the University of Washington.

-NSF-

Media Contacts Cheryl Dybas, NSF, (703) 292-7734, cdybas@nsf.gov
David Tenenbaum, U. Wisconsin-Madison, (608) 265-8549,

djtenenb@wisc.edu

Related WebsitesConservation Corridor Digests:

 http://www.conservationcorridor.org/#

The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2014, its budget is $7.2 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

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Aerial view of a conservation corridor experiment shows four patches of habitat in a pine forest.
Credit and Larger Version

Meteorological towers measured three-dimensional wind speed as part of the study.
Credit and Larger Version

Glow-in-the-dark seeds were created to determine whether corridors affect where seeds go.
Credit and Larger Version

Dirk Baker releases seeds that glow in the dark; seeds are retrieved at night with a black light.
Credit and Larger Version

 The National Science Foundation (NSF)
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com

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NASA - NASA, Newseum Present Media Preview Of PBS' Earth From Space

Global Weather Machine

• By Mark Hoover
• Posted 10.13.98
• NOVA

We live in an ocean of air, seething and flowing around us, changing-sometimes violently-every day. In the heart of this swirling machinery of rain clouds and jetstreams, hot desert winds and frozen arctic storms, there is one constant: change. A trillion and a half days have passed since the Earth was born in a spinning disk of stardust, and no two of those days have ever had the same weather.

This NASA image of wind patterns over the Pacific Ocean gives a sense of the dynamism of global weather. Enlarge Photo credit: NASA

what is weather?

Driven by the heat of the sun, weather is an interlocking system of cycles. Water evaporates, rises, cools, and falls as rain, only to evaporate once again. The sun rises and sets every day, with the air warming and cooling in response, and the cycle endlessly repeating. Low pressure systems suck high pressure systems into their vacuum, creating spinning masses of wind and clouds bigger than Texas; these cyclones are swept across the skies by persistent high-speed winds miles up in the atmosphere, rivers of air in a relentless race around the globe. Weather, in all its cycles and clashes, arises from a simple fact: the sun heats some parts of the Earth more than others.

Because the Earth is a globe, and not a flat board, the sun shines almost straight down on the tropics, baking them every day of the year. But at the poles, the angle is small and the sun's rays are weak, and the poles are therefore cold. Nature "abhors" this imbalance, and tries to fix it. As quickly as solar heat flows in to the tropics, it begins flowing out toward the poles, seeking to equalize the difference. The unrelenting march of this energy-on-the-move, from high concentration to low concentration, is the piston in the engine that propels weather.

When warm air leaves the tropics and heads toward the poles, cold air from near the poles is sucked back toward the tropics. This exchange sets up two-lane highways for air rushing to and from the tropics. These highways of air are called convection cells, and they are the reason wind blows.

The major surface wind bands of Earth. Each hemisphere is divided into three belts. The path of a storm greatly depends upon the wind belt in which it is located. The easterly (west-blowing) trade winds of both hemispheres collide near the equator, in a region called the Intertropical Convergence Zone (ICTZ). Enlarge Photo credit: University of Illinois WW2010 Project

Air flowing back and forth in these great cells is pushed sideways by the Earth's rotation, dragged by friction with the land and the sea, and squeezed by gravity. All of these distortions cause turbulent mixing of the winds, and soon lead to the organization of storm centers due to unevenness between warm and cold. In particular, the sideways push given the winds by the spinning of the planet-called the Coriolis Effect-causes the constant convective flows to organize in bands, where the flow direction varies according to latitude. These bands are responsible for prevailing winds on the surface, and jetstreams high in the atmosphere.

The ITCZ on this satellite image is the band of bright clouds located just north of the equator. This zone is a prolific contributor of storms and clouds to the world's weather. Enlarge Photo credit: NASA

We can see these bands of wind clearly in Jupiter's atmosphere, because Jupiter rotates at a furious pace, once every ten hours. We can also see them clearly on Earth when we take a picture from far out in space.

As on Earth, Jupiter shows distinct wind bands generated by convection and rotation forces. Scientists have measured wind speeds in Jupiter's "Little Red Spot" reaching up to about 384 miles per hour—twice as fast as the winds of a Category 5 hurricane. Enlarge Photo credit: NASA

El Niño'S POWER

El Niño exploits this organization of winds into bands when it causes major weather changes around the world. Specifically, El Niño can affect the path of flow in these bands, and the cyclones that are ushered across the surface by them are now delivered to different areas than normal. Think of the wind bands—both at the surface and high in the sky—as a tram, a streetcar on which storm systems hitch a ride as they travel around the Earth. El Niño moves the tracks—the stormtracks—of this tram. The answer to the puzzle of how this happens is literally blowing in the wind.

How does El Niño take over such a huge system? It begins with an effect due to the vastness of the Pacific Ocean itself, an effect intimately related to the birth of an El Niño. In the Pacific near the equator, the prevailing winds blow from east to west, as cool air sinking from higher latitudes toward the equator gets whipped sideways by the Coriolis force. We know these as the tradewinds, which sailors of old could always depend upon to blow steadily in the same direction.

In the tropical Pacific, these west-blowing tradewinds push steadily against the sea for thousands of miles. The warm water on the surface is literally blown sideways, and the water piles up in the west, creating a pool thousands of miles across. This leads to a heat imbalance: as more and more warm water is stripped from the east and moved west, cold waters from deep in the ocean near South America are drawn up to take its place. This cool water inhibits evaporation and the creation of rain clouds in east, which is why the Galapagos Islands and the coast of Peru are usually deserts.

The El Niño temperature anomaly of 1997-98 (appearing here as a red band in the Pacific Ocean) affected weather worldwide. Enlarge Photo credit: NASA / Image by R.B. Husar, Washington University; the land layer from the SeaWiFS Project; fire maps from the European Space Agency; the sea surface temperature from the Naval Oceanographic Office's

Just the opposite effect happens in the west, near Australia: intense rain cloud formation occurs as warm moist air, heated by the warm sea, rises and condenses into clouds. These clouds carry the drenching rains of the monsoons upon which the entire region of Indonesia and Southeast Asia depends. The huge volumes of rising warm air create a vacuum as they move upward, which draws cooler air from the east to replace it, strengthening the tradewinds and reinforcing the entire cycle. Another two-lane convection highway is created, but instead of between the equator and the poles, this one is between coastal South America and the region of Australia.

Here's where it gets interesting, the crux of the mystery of El Niño. This cycle should be self-perpetuating. But it's not. For unknown reasons, every few years, something hidden in the machinery causes the west-blowing tradewinds to slacken in the Pacific. The warm waters, which have been held by the winds in a pile 5 feet above sea level in the west, begin to flow back across the sea, drawn down by gravity, like a river breaching a levee. This massive surge of heated water shoots across the ocean and repositions itself near South America. East becomes west. Because of the heated water, all of the rainmaking that normally would happen in the west now happens in the east, and the convection cell reverses flow, which means rising warm air in the east sucks in the air from the west, and the tradewinds actually reverse their direction. Because the water in the west is now comparatively cool, rainmaking stops. The monsoons fail in Indonesia, but unending rains begin in Peru. The Child has arrived.

In its new, temporary headquarters off South America, the warm pool's heat again creates a huge mass of warm moist air, which bulges into the zones of prevailing winds at the surface as well as high in the air. Like a car dumped in a stream, this foreign obstruction creates ripples and waves "downstream" in the vast air rivers that circulate the Earth. These ripples cascade outward, pushing and disturbing the midlatitude jetstreams which sweep weather across the temperate zones. Off the west coast of North America, the bulging effect is pronounced. Pacific storms which normally would remain in the tropics now have an open door to the west coast, as the jet stream lurches north. California, Mexico, and even British Columbia brace for an onslaught of winter rain.

When a very strong El Niño strikes surface waters in the equatorial Pacific Ocean, warm water anomalies (red) develop in the Central Pacific. Winds that normally blow in a westerly direction weaken, allowing the easterly winds to push the warm water up against the South American coast. Enlarge Photo credit: NASA

After lurching north, the jet stream (like everything else in the system) tries to compensate for its too-far north motion by diving south, usually over the Rocky Mountains. It then snakes north again, creating the classic El Niño pattern. Because the jet stream represents a boundary between cold northern air and warm moist southern air, meteorologists are able to make general predictions for weather in an El Niño winter.

For starters, Pacific storms form farther east than usual. The northward bulge of the jet stream then conducts these abnormal storms into California and Mexico. Meanwhile, normal winter storms that would otherwise be steered through Washington and Oregon now veer northward toward the coast of Alaska, eventually being guided east into Canada. The west coast gets drenched; the Canadian Rockies get record snowfalls.

By strengthening east-blowing winds in the Caribbean, El Niño also creates a favorable environment for storms to develop in the Gulf of Mexico, and the displaced jetstream lets these storms pass up into the southeast of the United States. Florida and the southeastern states have a cool, abnormally rainy winter. A similar strengthening of the east-blowing winds in the Southern Hemisphere during its winter season brings massive storms to southern Brazil, Chile and Argentina.

In the midwest and northeast, the jetstream's strange dip and rise keeps colder Canadian air stuck in Canada, far north of its usual winter position. Acting as a boundary between this cold northern air and mild southern air, the displaced jetstream lets Chicago and New York enjoy a relatively warm, if somewhat wet, winter.

Because the rain machine in the west stops working, southeast Asia and Australia suffer devastating droughts. Meanwhile, North and South America get drenched, because the rain machine in the east is working overtime. Farther downstream in the great wind bands that circle the globe, El Niño continues to create havoc. By using the bands of prevailing winds as avenues along which to transmit its disruptive waves, El Niño eventually influences weather in Africa, the North Atlantic, even the Middle East. Teleconnected to distant regions by the Earth's rivers of air, El Niño invades the global weather machine.

This feature originally appeared on the site for the NOVA program Tracking El Nino.

NASA, Newseum Present Media Preview Of PBS' Earth From Space

 

 

WASHINGTON -- NASA and the Newseum will host a preview for news media of the upcoming NOVA special, "Earth from Space," at noon EST Monday, Feb. 4, at the Newseum, 555 Pennsylvania Ave. NW in Washington.

"Earth from Space" is scheduled to air nationwide at 9 p.m. EST Feb. 13 on Public Broadcasting Service television stations. The two-hour special explores how satellites are transforming our view of Earth and features interviews with scientists and new visualizations of our complex planet. The centerpiece of the program is an animation of the globe composed of 23 layers of satellite-based data and more than 125,000 images from space.

A question-and-answer session with scientists appearing in "Earth from Space" will follow the screening of the 20-minute preview. The panelists are:

-- Paula Apsell, senior executive producer, NOVA, and director of the WBGH science unit, Boston
-- Piers Sellers, deputy director, Sciences and Exploration Directorate, Goddard Space Flight Center, Greenbelt, Md.
-- Waleed Abdalati, director, Earth Science and Observation Center, University of Colorado, Boulder
-- Jeff Halverson, associate professor, University of Maryland, Baltimore County

To attend, news media representatives must register in advance no later than Friday, Feb. 1, with Steve Cole by telephone at 202-358-0918 or by email at stephen.e.cole@nasa.gov.

NOVA is produced by WGBH. For more information on "Earth from Space," visit:

http://www.pbs.org/wgbh/nova/space/earth-from-space.html

 NASA

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com

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Science: Scientists Find Night-Warming Effect Over Large Wind Farms in Texas

Hi My Friends: A VUELO DE UN QUINDE EL BLOG., Large wind farms in certain areas in the United States appear to affect local land surface temperatures, according to a paper published today in the journal Nature Climate Change.

Night-time land surface temperature differences near wind farms between 2010 and 2013.

Credit: Liming Zhou et al., Nature Climate Change.

Wind farms are numerous in parts of Texas; scientists report new results on their effects.

Credit: U.S. Department of Energy

Locations of clusters of Texas wind farms, as of the year 2010.

Credit: State of Texas

Wind farms dot the horizon in Lubbock County and other Texas areas.

Credit: Lubbock County, Texas

A new kind of Texas ranch--a wind ranch.

Credit: Wikimedia Commons

A Texas wind farm shares space with cacti and other desert-dwellers.

Credit: Wikimedia Commons

Large wind farms in certain areas in the United States appear to affect local land surface temperatures, according to a paper published today in the journal Nature Climate Change.

The study, led by Liming Zhou, an atmospheric scientist at the State University of New York- (SUNY) Albany, provides insights about the possible effects of wind farms.

The results could be important for developing efficient adaptation and management strategies to ensure long-term sustainability of wind power.

"This study indicates that land surface temperatures have warmed in the vicinity of large wind farms in west-central Texas, especially at night," says Anjuli Bamzai, program director in the National Science Foundation's (NSF) Division of Atmospheric and Geospace Sciences, which funded the research.

"The observations and analyses are for a relatively short period, but raise important issues that deserve attention as we move toward an era of rapid growth in wind farms in our quest for alternate energy sources."

Considerable research has linked the carbon dioxide produced by burning fossil fuels with rising global temperatures.

Consequently, many nations are moving toward cleaner sources of renewable energy such as wind turbines. Generating wind power creates no emissions, uses no water and is likely "green."

"We need to better understand the system with observations, and better describe and model the complex processes involved, to predict how wind farms may affect future weather and climate," said Zhou.

There have been a growing number of studies of wind farm effects on weather and climate, primarily using numerical models due to the lack of observations over wind farms.

As numerical models are computationally intensive and have uncertainties in simulating regional and local weather and climate, said Zhou, remote sensing is likely the most efficient and effective way to study wind farm effects over larger spatial and longer temporal scales.

To understand the potential impact of wind farms on local weather and climate, Zhou's team analyzed satellite-derived land surface temperatures from regions around large wind farms in Texas for the period 2003-2011.

The researchers found a night-time warming effect over wind farms of up to 0.72 degrees Celsius per decade over the nine-year-period in which data were collected.

Because the spatial pattern of warming mirrors the geographic distribution of wind turbines, the scientists attribute the warming primarily to wind farms.

The year-to-year land surface temperature over wind farms shows a persistent upward trend from 2003 to 2011, consistent with the increasing number of operational wind turbines with time.

"This warming effect is most likely caused by the turbulence in turbine wakes acting like fans to pull down warmer near-surface air from higher altitudes at night," said Somnath Baidya Roy of the University of Illinois at Urbana-Champaign, a co-author of the paper.

While the warming effect reported is local and small compared to the strong background year-to-year land surface temperature variation, the authors believe that this work draws attention to an important scientific issue that requires further investigation.

"The estimated warming trends only apply to the study region and to the study period, and thus should not be interpolated into other regions, globally or over longer periods," Zhou said. "For a given wind farm, once there are no new wind turbines added, the warming effect may reach a stable level."

The study represents a first step in exploring the potential of using satellite data to quantify the possible effects of the development of big wind farms on weather and climate, said Chris Thorncroft of SUNY-Albany, a co-author of the paper.

"We're expanding this approach to other wind farms," said Thorncroft, "and building models to understand the physical processes and mechanisms driving the interactions of wind turbines and the atmosphere boundary layer near the surface."

Other authors of the paper include Lance Bosart at SUNY-Albany, Yuhong Tian of NOAA, and Yuanlong Hu at Terra-Gen Power LLC in San Diego, Calif.

-NSF-

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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