Subscribe free to our newsletters via your
. 24/7 Space News .




CLIMATE SCIENCE
Cities Affect Temperatures For Thousands Of Miles
by Staff Writers
Boulder CO (SPX) Jan 31, 2013


This composite image shows a global view of Earth at night, compiled from over 400 satellite images. New research shows that major cities, which generally correspond with the nighttime lights in this image, can have a far-reaching impact on temperatures. Credit: NASA and NOAA.

Even if you live more than 1,000 miles from the nearest large city, it could be affecting your weather.

In a new study that shows the extent to which human activities are influencing the atmosphere, scientists have concluded that the heat generated by everyday activities in metropolitan areas alters the character of the jet stream and other major atmospheric systems. This affects temperatures across thousands of miles, significantly warming some areas and cooling others, according to the study in Nature Climate Change.

The extra "waste heat" generated from buildings, cars, and other sources in major Northern Hemisphere urban areas causes winter warming across large areas of northern North American and northern Asia. Temperatures in some remote areas increase by as much as 1 degree Celsius (1.8 degrees Fahrenheit), according to the research by scientists at the Scripps Institution of Oceanography, University of California, San Diego; Florida State University; and the National Center for Atmospheric Research.

At the same time, the changes to atmospheric circulation caused by the waste heat cool areas of Europe by as much as 1 degree C (1.8 degrees F), with much of the temperature decrease occurring in the fall.

The net effect on global mean temperatures is nearly negligible-an average increase worldwide of just 0.01 degrees C (about 0.02 degrees F). This is because the total human-produced waste heat is only about 0.3 percent of the heat transported across higher latitudes by atmospheric and oceanic circulations.

However, the noticeable impact on regional temperatures may explain why some regions are experiencing more winter warming than projected by climate computer models, the researchers conclude. They suggest that models be adjusted to take the influence of waste heat into account.

"The burning of fossil fuel not only emits greenhouse gases but also directly affects temperatures because of heat that escapes from sources like buildings and cars," says NCAR scientist Aixue Hu, a co-author of the study. "Although much of this waste heat is concentrated in large cities, it can change atmospheric patterns in a way that raises or lowers temperatures across considerable distances."

The researchers stressed that the effect of waste heat is distinct from the so-called urban heat island effect. Such islands are mainly a function of the heat collected and re-radiated by pavement, buildings, and other urban features, whereas the new study examines the heat produced directly through transportation, heating and cooling units, and other activities.

The study, "Energy consumption and the unexplained winter warming over northern Asia and North America" appears this Sunday. It was funded by the National Science Foundation, NCAR's sponsor, as well as the Department of Energy and the National Oceanic and Atmospheric Administration.

Hu, along with lead author Guang Zhang of Scripps and Ming Cai of Florida State University, analyzed the energy consumption - from heating buildings to powering vehicles - that generates waste heat release. The world's total energy consumption in 2006 was equivalent to a constant-use rate of 16 terawatts (one terawatt, or TW, equals 1 trillion watts). Of that, an average rate of 6.7 TW was consumed in 86 metropolitan areas in the Northern Hemisphere.

Using a computer model of the atmosphere, the authors found that the influence of this waste heat can widen the jet stream.

"What we found is that energy use from multiple urban areas collectively can warm the atmosphere remotely, thousands of miles away from the energy consumption regions," Zhang says. "This is accomplished through atmospheric circulation change."

The release of waste heat is different from energy that is naturally distributed in the atmosphere, the researchers noted. The largest source of heat, solar energy, warms Earth's surface and atmospheric circulations redistribute that energy from one region to another. Human energy consumption distributes energy that had lain dormant and sequestered for millions of years, mostly in the form of oil or coal.

Though the amount of human-generated energy is a small portion of that transported by nature, it is highly concentrated in urban areas. In the Northern Hemisphere, many of those urban areas lie directly under major atmospheric troughs and jet streams.

"The world's most populated and energy-intensive metropolitan areas are along the east and west coasts of the North American and Eurasian continents, underneath the most prominent atmospheric circulation troughs and ridges," Cai says. "The release of this concentrated waste energy causes the noticeable interruption to the normal atmospheric circulation systems above, leading to remote surface temperature changes far away from the regions where waste heat is generated."

Energy consumption and the unexplained winter warming over northern Asia and North America; Ghang J. Zhang, Ming Cai, and Aixue Hu; Nature Climate Change, Jan. 27, 2013

.


Related Links
National Center For Atmospheric Research/University Corporation For Atmospheric Research
Climate Science News - Modeling, Mitigation Adaptation






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








CLIMATE SCIENCE
Santiago de Chile will get drier and warmer
Santiago, Chile (SPX) Jan 31, 2013
Already nowadays ten per cent or more of the population in the Metropolitan Region of Santiago de Chile is affected by extreme heat or floods. These threats will tend to increase due to the continuous expansion of the Chilean capital, the consequent changes in land use and the influences of climate change. Because of that, the international research project ClimateAdaptationSantiago (CAS) ... read more


CLIMATE SCIENCE
US, Europe team up for moon fly-by

Russia to Launch Lunar Mission in 2015

US, Europe team up for moon fly-by

Mission would drag asteroid to the moon

CLIMATE SCIENCE
Ridges on Mars suggest ancient flowing water

Changes on Mars Caused by Seasonal Thawing of CO2

Is there life on Mars?

Opportunity At Work At Whitewater Lake

CLIMATE SCIENCE
Companies prepare commercial spacecraft

NASA to recycle parts for science work

TDRS-K Offers Upgrade to Vital Communications Net

How to predict the future of technology

CLIMATE SCIENCE
Reshuffle for Tiangong

China to launch 20 spacecrafts in 2013

Mr Xi in Space

China plans manned space launch in 2013: state media

CLIMATE SCIENCE
NASA to Send Inflatable Pod to International Space Station

ISS to get inflatable module

ESA workhorse to power NASA's Orion spacecraft

Competition Hopes To Fine Tune ISS Solar Array Shadowing

CLIMATE SCIENCE
Spacecom And Spacex Announce Agreement For Amos-6 Satellite Launch

S. Korea joins global space club with satellite launch

Russia Set for Year's First Baikonur Space Launch Feb. 5

First Ariane 5 For 2013 Ready For Loading

CLIMATE SCIENCE
The Origin And Maintenance Of A Retrograde Exoplanet

New Evidence Indicates Auroras Occur Outside Our Solar System

Glitch has space telescope shut down

Earth-size planets common in galaxy

CLIMATE SCIENCE
Bioinspired fibers change color when stretched

Stanford Researchers Break Million-core Supercomputer Barrier

Scientists trick iron-eating bacteria into breathing electrons instead

Demagnetization by rapid spin transport




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement