nsf.gov - National Science Foundation - Springtime night lights: Finding the aurora .- Luces de la noche de la primavera: Encontrar la aurora

Hola amigos: A VUELO DE UN QUINDE EL BLOG., hemos recibido información de la Fundación Nacional de Ciencias de Los Estados Unidos, dándonos conocimiento de la formación y vistas de las Auroras en el Hemisferio Norte. En realidad las auroras son una danza de partículas y magnetismo entre El Sol y La Tierra. Como sabemos El Sol constantemente produce vientos cargados de partículas o plasma y la llega a la Tierra como un "Aliento", que el campo magnético de la Tierra lo hace cambiar en forma redonda a largada, como si fuese una lágrima con una larga cola en la parte más alejada de El Sol.

Aurorasaurus project allows aurora-viewers around the world to compare sightings

St. Patrick's Day, 2015, brought a once-a-decade display of the aurora, here in "shamrock green." Credit and Larger Version

March 31, 2015

This is the seventh part in a series on NSF's geosciences risk and resilience interest area. See parts one, two, three, four, five and six.

Dance of the spirits, it's known by the Cree, one of North America's largest groups of Native Americans.

The phenomenon, called the aurora borealis in the Northern Hemisphere and aurora australis in the Southern Hemisphere, is indeed a dance of particles and magnetism between the sun and the Earth.

The sun continuously produces a solar wind of charged particles, or plasma. As that "breath" reaches Earth, it causes our planet's magnetic field to shapeshift from round to teardrop--with a long tail on the side farthest from the sun.

The teardrop-stretched field ultimately reconfigures into two parts, one controlled by Earth's magnetic field, the other by the solar wind.

The instability excites the solar-charged particles. They follow spiral paths along lines connecting Earth's north and south magnetic poles to its atmosphere.

"What happens next," says scientist Elizabeth MacDonald of the New Mexico Consortium in Los Alamos, "is one of nature's most spectacular sights: the aurora."

The light of the aurora is emitted when the charged particles collide with gases in Earth's upper atmosphere.

 

Glimpsing an aurora

 

How often the aurora is visible in an area, MacDonald says, depends upon a host of factors, including the intensity of the solar wind; the season--the aurora may be strongest around the spring and fall equinoxes; whether the sun is near the peak of its 11-year cycle; and how far someone is from what scientists call the auroral oval, the lights' ring-shaped display.

Knowing where and when an aurora is happening has been difficult to find out--until now. A new project called Aurorasaurus allows citizens around the world to track auroras and report on their progress. Aurorasaurus is designed by researchers from the New Mexico Consortium, Pennsylvania State University and Science Education Solutions.

Visitors to the Aurorasaurus website can see where an aurora is happening in real-time, let other Aurorasaurus visitors know of an aurora's existence, and receive "early warnings" when an aurora is likely to happen in their Earth-neighborhood.

 

Aurora-power

 

"Auroras are beautiful displays that have fascinated humans through the ages," says Therese Moretto Jorgensen, program director in the National Science Foundation's (NSF) Directorate for Geosciences, which, along with NSF's Directorate for Education and Human Resources and Directorate for Computer & Information Science & Engineering, funds Aurorasaurus through NSF's INSPIRE program.

INSPIRE supports projects whose scientific advances lie outside the scope of a single program or discipline, lines of research that promise transformational advances, and prospective discoveries at the interfaces of scientific boundaries.

"Auroras are of major interest," says Moretto Jorgensen, "because of their effects on Earth. There's a close relationship between auroras and the magnetic variations that pose a threat to the power grid.

"A better understanding of when and where auroras happen will help us develop models that can forecast these potentially hazardous events."

 

Amassing new data

 

Scientists hope that by amassing data from thousands of aurora-viewers, they'll learn more about the solar storms that can disrupt or destroy Earth's communications networks and affect the planet's navigation, pipeline, electrical and transportation systems.

During one solar storm in 1989, transformers in New Jersey melted and wiped out power all the way to Quebec, leaving millions of people in the dark.

The largest such solar storm in history, the Carrington Event, zapped Earth in 1859. It was so large it lit up the skies with auroras from the poles to the tropics. Electrical currents from the storm caused fires in telegraph systems and knocked out communications.

 

St. Patrick's Day magic in the skies

 

Could it happen again? Yes, if St. Patrick's Day this year is any guide.

On March 17, 2015, researchers and the public were treated to once-a-decade views. As people waited for glimpses of leprechauns, they saw something even more magical, viewers say.

Earth experienced the biggest solar storm to date of this 11-year sun cycle, sparking auroras around the world.

The St. Patrick's Day auroras, many of which were indeed green, were a fortuitous combination of events. Two days earlier, there was an explosion on the sun. The explosion, called a coronal mass ejection (CME), unleashed a blast of gas bubbles that created a strong disturbance as it collided with Earth's magnetic field.

The CME's magnetic field was directed southward, opposite to the Earth's magnetic field, and the solar wind whipped by very fast, says MacDonald.

"The storm's conditions led to a perfect environment for aurora-hunting," she says. On a scale of G1 (minor) to G5 (extreme), the storm reached a G4, or "severe" level.

The storm's Kp index, a global solar storm index, registered in the 6-8 range (9 is the highest).

 

Rare aurora-viewing--all the way to the southern U.S.

 

The strong solar wind blew for more than 24 hours, creating auroras visible as far south as the central and southern United States--a very rare occurrence.

The solar storm's peak hit during the daytime over most of the United States and Europe, but the storm persisted into the night and offered Americans and Europeans a brilliant nighttime light show.

Aurorasaurus reports came in from unusual regions: the south of England, Germany and Poland. In the United States, people spotted auroras in states such as Pennsylvania, Virginia and Colorado.

 

Data peak from Aurorasaurus users

 

Aurorasaurus participants logged more than 160 sightings during the St. Patrick's Day solar storm.

From midnight on March 17th through mid-day on March 18th, the number of registered users increased by 50 percent. Registering allows Aurorasaurus to communicate information in return, sending location-based sighting alerts.

"We combine reports to provide real-time alerts when auroras might be visible nearby," says MacDonald. "During this storm alone, we issued 361 such notifications.

"We're using Aurorasaurus data to improve auroral oval models, and to develop a better notification system using both satellite-based data and citizen science data."

Adds Moretto Jorgensen, "Auroras on a global scale are very difficult to capture using traditional scientific methods. Human observers linked through Aurorasaurus are a unique network for documenting them."

Whether on St. Patrick's Day or any other Earth-day, the aurora carries a message: take time to look up at one of the planet's most breathtaking sights.

Then look down, to be sure you can send photos of the event from your cell phone. Spirits dancing across the skies may have played havoc with its transmissions.

--	Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov

Investigators Andrea Tapia
Michelle Hall
Elizabeth MacDonald

Related Institutions/Organizations New Mexico Consortium

Related Awards #1344296 INSPIRE Track 1: Aurorasaurus - Citizen Scientists Experiencing the Extremes of Space Weather

Iceland is a common place to see the aurora borealis.
Credit and Larger Version

This red aurora, which happened on Oct. 24, 2011, stretched from Chicago to Alabama.
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Light from the aurora is emitted by atmospheric gases when they're hit by particles from space.
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Scientists launched a rocket-borne experiment into the northern lights to learn more about them.
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An aurora viewed from the International Space Station on Aug. 29, 2014.
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The National Science Foundation (NSF)

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

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NASA : Fall Colors Arriving

Hola amigos: A VUELO DE UN QUIND EL BLOG.,  aquí en la imagen estamos apreciando el Hemisferio Norte con los grandes lagos de Norteamérica, captada por NASA’s Terra satellite , cuya imagen se en The Moderate Resolution Imaging Spectroradiometer (MODIS)

 

Fall Colors Arriving

A few days after autumn showed up on the calendar in the Northern Hemisphere, it showed up on the landscape of North America. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this view of fall colors around the Great Lakes on Sept. 26, 2014.

The changing of leaf color in temperate forests involves several causes and reactions, but the dominant factors are sunlight and heat. Since temperatures tend to drop sooner and sunlight fades faster at higher latitudes, the progression of fall color changes tends to move from north to south across North America from mid-September through mid-November.

In late summer and autumn, tree and plant leaves produce less chlorophyll, the green pigment that harvests sunlight for plants to convert water and carbon dioxide into sugars. The subsidence of chlorophyll allows other chemical compounds in the leaves—particularly carotenoids and flavonoids—to emerge from the green shadow of summer. These compounds do not decay as fast as chlorophyll, so they shine through in yellows, oranges, and reds as the green fades. Another set of chemicals, anthocyanins, are associated with the storage of sugars and give the leaves of some species deep purple and red hues.

> More information

Image Credit: Jeff Schmaltz at NASA GSFC. Caption by Mike Carlowicz

NASA

Guillermo Gonzalo Sánchez Achutegui

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The National Science Foundation: Ancient ocean currents may have changed pace and intensity of ice ages

Slowing of currents may have flipped switch

About 950,000 years ago, North Atlantic currents, Northern Hemisphere ice sheets underwent changes. Credit and Larger Version

June 26, 2014

Climate scientists have long tried to explain why ice-age cycles became longer and more intense some 900,000 years ago, switching from 41,000-year cycles to 100,000-year cycles.

In a paper published this week in the journal Science, researchers report that the deep ocean currents that move heat around the globe stalled or may have stopped at that time, possibly due to expanding ice cover in the Northern Hemisphere.

"The research is a breakthrough in understanding a major change in the rhythm of Earth's climate, and shows that the ocean played a central role," says Candace Major, program director in the National Science Foundation (NSF)'s Division of Ocean Sciences, which funded the research.

The slowing currents increased carbon dioxide (CO₂) storage in the oceans, leaving less CO₂ in the atmosphere. That kept temperatures cold and kicked the climate system into a new phase of colder, but less frequent, ice ages, the scientists believe.

"The oceans started storing more carbon dioxide for a longer period of time," says Leopoldo Pena, the paper's lead author and a paleoceanographer at Columbia University's Lamont-Doherty Earth Observatory (LDEO). "Our evidence shows that the oceans played a major role in slowing the pace of the ice ages and making them more severe."

The researchers reconstructed the past strength of Earth's system of ocean currents by sampling deep-sea sediments off the coast of South Africa, where powerful currents originating in the North Atlantic Ocean pass on their way to Antarctica.

How vigorously those currents moved can be inferred by how much North Atlantic water made it that far, as measured by isotope ratios of the element neodymium bearing the signature of North Atlantic seawater.

Like tape recorders, the shells of ancient plankton incorporate these seawater signals through time, allowing scientists to approximate when currents grew stronger and when weaker.

Over the last 1.2 million years, the conveyor-like currents strengthened during warm periods and lessened during ice ages, as previously thought.

But at about 950,000 years ago, ocean circulation slowed significantly and stayed weak for 100,000 years.

During that period the planet skipped an interglacial--the warm interval between ice ages. When the system recovered, it entered a new phase of longer, 100,000-year ice age cycles.

After this turning point, deep ocean currents remained weak during ice ages, and ice ages themselves became colder.

"Our discovery of such a major breakdown in the ocean circulation system was a big surprise," said paper co-author Steven Goldstein, a geochemist at LDEO. "It allowed the ice sheets to grow when they should have melted, triggering the first 100,000-year cycle."

Ice ages come and go at predictable intervals based on the changing amount of sunlight that falls on the planet, due to variations in Earth's orbit around the sun.

Orbital changes alone, however, are not enough to explain the sudden switch to longer ice age intervals.

According to one earlier hypothesis for the transition, advancing glaciers in North America stripped away soils in Canada, causing thicker, longer-lasting ice to build up on the remaining bedrock.

Building on that idea, the researchers believe that the advancing ice might have triggered the slowdown in deep ocean currents, leading the oceans to vent less carbon dioxide, which suppressed the interglacial that should have followed.

"The ice sheets must have reached a critical state that switched the ocean circulation system into a weaker mode," said Goldstein.

Neodymium, a key component of cellphones, headphones, computers and wind turbines, also offers a good way of measuring the vigor of ancient ocean currents.

Goldstein and colleagues had used neodymium ratios in deep-sea sediment samples to show that ocean circulation slowed during past ice ages.

They used the same method to show that changes in climate preceded changes in ocean circulation.

A trace element in Earth's crust, neodymium washes into the oceans through erosion from the continents, where natural radioactive decay leaves a signature unique to the land mass from which it originated.

When Goldstein and Lamont colleague Sidney Hemming pioneered this method in the late 1990s, they rarely worried about surrounding neodymium contaminating their samples.

The rise of consumer electronics has changed that.

"I used to say you could do sample processing for neodymium analysis in a parking lot," said Goldstein. "Not anymore."

-NSF-

Media Contacts Cheryl Dybas, NSF, (703) 292-7734,

cdybas@nsf.gov
Kim Martineau, LDEO, (845) 365-8708,

kmartine@ldeo.columbia.edu

Related WebsitesNSF Grant: Late Quaternary Variability of the Agulhas Thermohaline Valve from Nd Isotopes in Planktonic Foraminifera:

 http://www.nsf.gov/awardsearch/showAward?AWD_ID=1031198&HistoricalAwards=false
International Ocean Discovery Program:

 http://www.iodp.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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Ocean currents slowed 950,000 years ago, triggering colder but less frequent ice ages.
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Scientists (pictured: Leo Pena) analyzed fossil plankton shells to reconstruct ocean circulation.
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In an Ultra Clean Lab, neodymium isotopes in fossils were isolated and measured.
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The scientific drillship JOIDES Resolution was used as a platform to collect deep-ocean sediment.
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The researchers' findings are described in the June 27 issue of Science.
Credit and Larger Versión

The National Science Foundation (NSF)

Guillermo Gonzalo Sánchez Achutegui

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NASA : Long-Term Warming Likely to Be Significant Despite Recent Slowdown

Five new NASA Earth science missions are launching in 2014 to expand our understanding of Earth’s changing climate and environment.

Feature Link:

NASA's "Earth Right Now" website

A new NASA study shows Earth's climate likely will continue to warm during this century on track with previous estimates, despite the recent slowdown in the rate of global warming.

This research hinges on a new and more detailed calculation of the sensitivity of Earth's climate to the factors that cause it to change, such as greenhouse gas emissions. Drew Shindell, a climatologist at NASA's Goddard Institute for Space Studies in New York, found Earth is likely to experience roughly 20 percent more warming than estimates that were largely based on surface temperature observations during the past 150 years.

Shindell's paper on this research was published March 9 in the journal Nature Climate Change.

A new NASA study suggests that projections of Earth's future warming should be more in line with previous estimates that indicated a higher sensitivity to increasing greenhouse gas emissions.

Image Credit: NASA SVS/NASA Center for Climate Simulation

Global temperatures have increased at a rate of 0.22 Fahrenheit (0.12 Celsius) per decade since 1951. But since 1998, the rate of warming has been only 0.09 F (0.05 C) per decade -- even as atmospheric carbon dioxide continues to rise at a rate similar to previous decades. Carbon dioxide is the most significant greenhouse gas generated by humans.

Some recent research, aimed at fine-tuning long-term warming projections by taking this slowdown into account, suggested Earth may be less sensitive to greenhouse gas increases than previously thought. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), which was issued in 2013 and was the consensus report on the state of climate change science, also reduced the lower range of Earth's potential for global warming.

To put a number to climate change, researchers calculate what is called Earth's "transient climate response." This calculation determines how much global temperatures will change as atmospheric carbon dioxide continues to increase – at about 1 percent per year -- until the total amount of atmospheric carbon dioxide has doubled. The estimates for transient climate response range from near 2.52 F (1.4 C) offered by recent research, to the IPCC's estimate of 1.8 F (1.0 C). Shindell's study estimates a transient climate response of 3.06 F (1.7 C), and determined it is unlikely values will be below 2.34 F (1.3 C).

Shindell's paper further focuses on improving our understanding of how airborne particles, called aerosols, drive climate change in the Northern Hemisphere. Aerosols are produced by both natural sources – such as volcanoes, wildfire and sea spray – and sources such as manufacturing activities, automobiles and energy production. Depending on their make-up, some aerosols cause warming, while others create a cooling effect. In order to understand the role played by carbon dioxide emissions in global warming, it is necessary to account for the effects of atmospheric aerosols.

While multiple studies have shown the Northern Hemisphere plays a stronger role than the Southern Hemisphere in transient climate change, this had not been included in calculations of the effect of atmospheric aerosols on climate sensitivity. Prior to Shindell's work, such calculations had assumed aerosol impacts were uniform around the globe.

This difference means previous studies have underestimated the cooling effect of aerosols. When corrected, the range of likely warming based on surface temperature observations is in line with earlier estimates, despite the recent slowdown.

One reason for the disproportionate influence of the Northern Hemisphere, particularly as it pertains to the impact of aerosols, is that most man-made aerosols are released from the more industrialized regions north of the equator. Also, the vast majority of Earth's landmasses are in the Northern Hemisphere. This furthers the effect of the Northern Hemisphere because land, snow and ice adjust to atmospheric changes more quickly than the oceans of the world.

"Working on the IPCC, there was a lot of discussion of climate sensitivity since it's so important for our future," said Shindell, who was lead author of the IPCC Fifth Assessment Report's chapter on Anthropogenic and Natural Radiative Forcing. "The conclusion was that the lower end of the expected warming range was smaller than we thought before. That was a big discussion. Yet, I kept thinking, we know the Northern Hemisphere has a disproportionate effect, and some pollutants are unevenly distributed. But we don't take that into account. I wanted to quantify how much the location mattered."

Shindell's climate sensitivity calculation suggests countries around the world need to reduce greenhouse gas emissions at the higher end of proposed emissions reduction ranges to avoid the most damaging consequences of climate change. "I wish it weren't so," said Shindell, "but forewarned is forearmed."

For more information about the Goddard Institute for Space Studies, visit:

http://www.giss.nasa.gov

NASA

Guillermo GOnzalo Sánchez Achutegui

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nsf.gov - Discovery - Summertime: Hot Time in the City

Parks are islands of coolness in cities' urban heat.-

In summer, extreme heat events are on the way in cities like Phoenix. Credit: NSF Central-Arizona Phoenix LTER Site

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The 'urban heat island effect' raises temperatures in cities compared with surrounding areas. Credit: NASA

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Sherman Park, part of a low-income Phoenix neighborhood in need of green spaces. Credit: Sharon Harlan

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Vegetation (red), soil (brown, tan), built materials (white) in a south Phoenix neighborhood. Credit: NASA

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Researchers Chris Martin, Darrel Jenerette (background) conducting field work in Phoenix. Credit: Sharon Harlan

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Across the nation and around the world, urban areas are heating up. Credit: Dustin Phillips/Creative Commons

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The following is part ten in a series on the National Science Foundation's Science, Engineering and Education for Sustainability (SEES) investment. Visit parts one, two, three, four, five, six, seven, eight and nine in this series.

It's the first day of summer, a hot time in the desert city of Phoenix. And in cities across the United States--and the Northern Hemisphere.

Heat islands, as these urban hot spots are called, are metropolitan areas significantly warmer than surrounding rural areas. Why?

"Us," says sociologist Sharon Harlan of Arizona State University (ASU). "It's all due to the effects of humans. We've modified the surface of the land in ways that retain heat."

Urban heat islands are the result. Soil and grass have been replaced with materials such as asphalt and concrete that absorb heat during the day and re-radiate it at night, causing higher temperatures. 

Summer in a blistering desert

Harlan and colleagues in fields across the social, natural and health sciences are studying urban heat islands--and their opposites, park cool islands where plant growth throws cold water on burning temperatures.

They're conducting the research via a National Science Foundation (NSF) Coupled Natural and Human Systems (CNH) grant. CNH is one of NSF's Science, Engineering and Education for Sustainability, or SEES, programs.

"Cities can be hot and uncomfortable places for the people who live in them, with some populations especially vulnerable to health problems from urban heat," says Sarah Ruth, CNH program director in NSF's Directorate for Geosciences.

"The city environment and its human inhabitants form a complex system with multiple connections. These researchers have uncovered important information about this system and the interactions among its components.

"The results suggest ways city officials and residents can work together to create places where fewer people suffer the effects of extreme temperatures."

The hot, arid Sonoran Desert is central Arizona's natural environment. Humans have transformed the desert over thousands of years, beginning with early Native American subsistence farmers and continuing with late 19th century Anglo-American commercial growers and 20th century sunbelt migrants.

Metropolitan Phoenix is an ideal laboratory for investigating heat-related human vulnerability, says Harlan. Rapid urbanization has replaced natural vegetation and agricultural fields, increasing summer temperatures during the past 50 years.

Islands of green

What's one of the answers? Park cool islands, found the scientists.

They evaluated the effects of plants' cool greenness on a Phoenix inner-city park.

The results were recently published in the journal Urban Ecosystems. Along with Harlan, co-authors of the paper, all from ASU, are Juan Declet-Barreto, Anthony Brazel, Chris Martin and Winston Chow.

They're also working through the NSF Central Arizona-Phoenix Long-Term Ecological Research (LTER) site, one of 26 such NSF LTER sites across the nation and around the world.

"We predicted air and surface temperatures under two different vegetation regimes: existing conditions representative of Phoenix urban core neighborhoods, and a scenario using principles of landscape design and architecture, and urban heat island mitigation strategies," write the scientists.

They found that the air beneath and around "canopied vegetation"--trees--was cooler than the surroundings.

Larger plants such as trees absorb and reflect the Sun's rays, buffering the heat index. Scientists call it a "microclimate ecosystem service," better known as, simply, shade.

Trees also reduce hot air by turning water from liquid to gas inside their leaves. "Temperatures then fall in the immediate environment," says Martin.

It all adds up to a park cool island. "Park cool islands are usually found in irregular patterns in a city," Declet-Barreto says. "They're nested within warmer spots."

The Latino Urban Core

The team studied the role of park cool islands in a low-income, ethnic minority community in inner-city Phoenix.

The area is called the Latino Urban Core. It's bounded by industrial land to the north, south and east and an interstate highway to the west. The neighborhood's main feature is an electric utility company easement currently used as "linear park space almost entirely devoid of vegetation," states the Urban Ecosystems paper.

The Latino Urban Core's sparse vegetation is mostly in residents' yards. Patches of exposed soil with nothing growing on them are scattered across vacant lots, yards, and the grounds of the "linear park."

Parks in low-income neighborhoods tend to be hotter than parks in higher-income areas, research has shown. Although residents in low-income areas need places to cool off, these neighborhoods have less inherent cooling capacity as there's less green space.

Inner-city green space--lacking in Phoenix's Latino Urban Core--is a crucial component of urban heat island mitigation, Declet-Barreto says. "But it's made more difficult by ongoing debates over urban amenities like parks and the needed resources, such as water, tax dollars, local government will and regular maintenance."

"Ecologies of fear" often arise in neglected green spaces. "They're legacies of environmental and racial discrimination, inner-city decay and a continuing urban planning focus on fringe [suburban] development," write the researchers.

Studies have shown that in Phoenix, inner-city areas bear higher property tax burdens in comparison with suburbs, but the former receive significantly fewer tax dollars for parks, recreation and water supplies.

Minority and low-income communities are increasingly addressing such disparities by demanding a more equitable distribution of urban amenities, such as green spaces like parks.

In low-income communities, parks are often the only available public gathering places. Green spaces, scientists say, can provide cultural, social and--more directly applicable to extreme heat mitigation--human health and ecological benefits.

Cooling down urban heat islands

Finding ways to offset National Science Foundation (NSF)high temperatures in desert cities where the weather is chronically hot, says Harlan, is critical.

Extreme heat, scientists have found, is a threat to human health, increases atmospheric pollutants and energy and water use, alters regional hydrology and affects interactions between humans and ecological processes.

"The problem of heat-related deaths and illnesses is very serious," says Harlan. "Each year, heat fatalities in the U.S. happen in greater numbers than mortality from any other type of weather disaster." High heat wave events--unexpected and long-duration heat waves--are becoming more common in cities like Phoenix, Chicago and Paris.

Climate change and rapidly growing cities are likely to fuel more such events.

"Our research suggests that climate intervention strategies should be targeted at the neighborhoods and population groups that are most vulnerable to environmental hazards like extreme heat events," says Harlan. "We hope our results will be used in better decision-making about climate adaptation in cities."

Greening parks is an intervention strategy, she says, for urban heat island mitigation that could be supported with public resources.

"If targeted to low-income neighborhoods where vulnerability to heat is greater," says Harlan, "it would address an environmental inequity and provide better ecosystem services for these neighborhoods."

One antidote to an urban heat island, it turns out, is another island, a place filled with shade trees and lush growth: a park cool island.

--

Cheryl Dybas, NSF (703) 292-7734

cdybas@nsf.gov

Related Websites
NSF Science, Engineering and Education for Sustainability Programs:

 http://www.nsf.gov/sees
NSF Publication: Discoveries in Sustainability: 

http://www.nsf.gov/pubs/2012/disco12001/disco12001.pdf
NSF News Release: National Science Foundation Awards Grants for Research on Coupled Natural and Human Systems:

 http://www.nsf.gov/news/news_summ.jsp?cntn_id=125578

 The National Science Foundation (NSF).-

 Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com

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