The new observations-based study confirms that aerosols have the net effect of cooling the planet-in agreement with previous understanding -- but arrives at the answer in a completely new way that is more straightforward and narrows the uncertainties of the estimate.
The researchers, led by Daniel M. Murphy of the National Oceanic and Atmospheric Administration's (NOAA) Earth System Research Laboratory in Boulder, Colo., applied fundamental conservation of energy principles to construct a global energy "budget." This budget tallies the climate's "credits" and "debits"--heating and cooling processes-- since 1950, using only observations and straightforward calculations without the more complicated algorithms of global climate models. The authors then calculated the cooling effect of the aerosols as the only missing term in the budget, arriving at an estimate of 1.1 watts per square meter.
The teams' findings are published today in Journal of Geophysical Research- Atmospheres, a journal of the American Geophysical Union (AGU).
(IPCC) that estimated aerosol cooling at 1.2 watts per square meter. But the new study places that estimate on more solid ground and rules out the larger cooling effects that were previously thought to be possible.
"The agreement boosts our confidence in both the models and the new approach," Murphy says. "Plus, we've been able to pin down the amount of cooling by aerosols better than ever."
The narrower bounds on aerosol effects will help in predicting climate change and accounting for climate change to date.
In balancing the budget for the processes perturbing the heating and cooling of the Earth, Murphy and colleagues found that since 1950, the planet released about 20 percent of the warming influence of heat-trapping greenhouse gases to outer space as infrared energy.
Volcanic emissions lingering in the stratosphere offset about 20 percent of the heating by bouncing solar radiation back to space before it reached the surface. Cooling from the lower- atmosphere aerosols produced by humans balanced 50 percent of the heating. Only the remaining 10 percent of greenhouse-gas warming actually went into heating the Earth, and almost all of it went into the ocean.
The new study tackled what the IPCC has identified as one of the most uncertain aspects of the human impacts on climate. Aerosols have complex effects on climate; sulfate particles formed from pollution can cool the Earth directly by reflecting sunlight, while soot from biomass burning absorbs sunlight and warms the Earth. Aerosols can also affect the formation and properties of clouds, altering their influence on climate. The net effect of all these direct and indirect factors is a cooling by aerosols, which has partially offset the warming by greenhouse gases.
Modeling magma to find copper
13.01.2017 | Université de Genève
What makes erionite carcinogenic?
13.01.2017 | Friedrich-Schiller-Universität Jena
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...
Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.
Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
16.01.2017 | Power and Electrical Engineering
16.01.2017 | Information Technology
16.01.2017 | Power and Electrical Engineering