Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 


Study finds energy use in cities has global climate effects

Researchers find that heat given off by metropolitan areas can lead to continental-scale winter warming in high latitudes

The heat generated by everyday energy consumption in metropolitan areas is significant enough to influence the character of major atmospheric circulation systems, including the jet stream during winter months, and cause continental-scale surface warming in high latitudes, according to a trio of climate researchers that includes Ming Cai, a professor in Florida State University's Department of Meteorology.

Led by Guang Zhang, a research meteorologist at Scripps Institution of Oceanography at the University of California, San Diego, the scientists report in the journal Nature Climate Change that waste heat released in major cities in the Northern Hemisphere causes as much as 1 degree C (1.8 degrees F) of continental-scale winter warming in high latitudes of the North America and Eurasian continents. They added that this effect helps to explain the disparity between actual observed warming in the last half-century and the amount of warming predicted by computer models that only include anthropogenic greenhouse gases and aerosols.

The study, "Energy Consumption and the Unexplained Winter Warming Over Northern Asia and North America," appears in online editions of the journal on Jan. 27. The study was funded in part by the National Oceanic and Atmospheric Administration's Climate Program Office.

Cai, Zhang and Aixue Hu of the National Center for Atmospheric Research in Boulder, Colo., considered the energy consumption — from heating buildings to powering vehicles — that generates waste heat release. The world's total energy consumption in 2006 was 16 terawatts (one terawatt equals 1 trillion watts). Of that, 6.7 terawatts were consumed in the 86 metropolitan areas considered in this study.

"The burning of fossil fuel not only emits greenhouse gases but also directly effects temperatures because of heat that escapes from sources like buildings and cars," Hu said.

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 the Earth's surface. Atmospheric circulations distribute that energy from one region to another. Human energy consumption distributes energy that remained 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.

"The world's most populated metropolitan areas, which also have the highest rates of energy consumption, are along the east and west coasts of the North American and Eurasian continents, underneath the most prominent atmospheric circulation troughs and ridges," Cai said. "The concentrated and intensive release of waste energy in these areas causes a noticeable interruption to normal atmospheric circulation systems, leading to remote surface temperature changes far away from the regions where the waste heat is generated."

The authors report that the influence of urban heat can widen the jet stream at the extratropics, or area outside the tropics. They add that the heating is not uniform. Partially counterbalancing it, the changes in major atmospheric systems cool areas of Europe by as much as 1 degree C, with much of the temperature decrease occurring in the fall.

The study does not address whether the urban heating effect disrupts atmospheric weather patterns or plays a role in accelerating global warming, though Zhang said drawing power from renewable sources such as solar or wind provides a societal benefit in that it does not add net energy into the atmosphere.

Zhang said the climate impact this research studied is distinct from the so-called urban heat island effect, an increase in the warmth of cities compared to unpopulated areas caused by land use changes. Such island effects are mainly a function of the heat collected and re-radiated by pavement, buildings and other urban features.

"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 said. "This is accomplished through atmospheric circulation change."

They also find observational evidence indicates that the waste heat can be the "missing forcing" that would account for the discrepancy between the observed temperature change and that is simulated in computer models forced only by anthropogenic greenhouse gases and aerosols. They suggest that the influence of energy consumption should be considered, in addition to heat-trapping gases and aerosols, as necessary anthropogenic factors in computer models to predict the future climate.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage the nation's coastal and marine resources.

Ming Cai | EurekAlert!
Further information:

More articles from Ecology, The Environment and Conservation:

nachricht Blacklists Protect the Rainforest
24.09.2015 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Small Alga – Great Effect
22.09.2015 | Leibniz-Zentrum für Marine Tropenökologie (ZMT)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neue Sinumerik-Funktionen steigern Produktivität und Genauigkeit

EMO 2015, Halle 3, Stand E06/F03

  • Antriebsoptimierung aus Teileprogramm ermöglicht höhere Produktivität
  • Automatische Umschaltung der Dynamikwerte für Eilgang und Bearbeitung steigert Qualität...

Im Focus: New Sinumerik features improve productivity and precision

EMO 2015, Hall 3, Booth E06/F03

  • Drive optimization called automatically by the part program boosts productivity
  • Automatically switching the dynamic values to rapid traverse and interpolation...

Im Focus: LZH zeigt additive Fertigung auf der LABVOLUTION

Das Laser Zentrum Hannover e.V. (LZH) zeigt vom 6. bis zum 8. Oktober 2015 auf der LABVOLUTION in Hannover in Halle 9, Stand E67/09 wie laserbasierte Technologien zum Labor der Zukunft beitragen können. Als Teil des Musterlabors smartLAB präsentiert das LZH, wie die additive Fertigung, besser bekannt als 3D-Druck, Versuchsaufbauten flexibler gestalten kann.

Zwölf Partner aus Wissenschaft und Industrie stellen auf der Sonderausstellung smartLAB ein intelligentes und innovatives Musterlabor vor. Teil dieses...

Im Focus: LZH presents additive manufacturing at the LABVOLUTION

The Laser Zentrum Hannover e.V. (LZH) will present how laser-based technologies can contribute to the laboratory of the future at the LABVOLUTION in Hannover in Hall 9, Stand E67/09, from October 6th to 8th, 2015. As a part of the model lab smartLAB, the LZH is showing how additive manufacturing, better known as 3-D printing, can make experimental setups more flexible.

Twelve partners from science and industry are presenting an intelligent and innovative model lab at the special display smartLAB. A part of this intelligent...

Im Focus: New polymer creates safer fuels

Before embarking on a transcontinental journey, jet airplanes fill up with tens of thousands of gallons of fuel. In the event of a crash, such large quantities of fuel increase the severity of an explosion upon impact.

Researchers at Caltech and JPL have discovered a polymeric fuel additive that can reduce the intensity of postimpact explosions that occur during accidents and...

Alle Focus-News des Innovations-reports >>>



im innovations-report
in Kooperation mit academics

Batterietagung im April 2016 in Münster

02.10.2015 | Veranstaltungen

EEHE 2016 – Call for Papers endet am 28.10.2015!

02.10.2015 | Veranstaltungen

HDT-Tagung: 16. Essener Brandschutztage

01.10.2015 | Veranstaltungen

Weitere VideoLinks >>>
Aktuelle Beiträge

Neue Sinumerik-Funktionen steigern Produktivität und Genauigkeit

02.10.2015 | Messenachrichten

Exklusives Design für die Raumbedienung mit den neuen KNX-Tastsensoren

02.10.2015 | Architektur Bauwesen

Schutz aus Glas gegen vielerlei Gefahren: Feuer, Beschuss, Vandalismus und UV-Strahlen

02.10.2015 | Materialwissenschaften