Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stratosphere temperature data support scientists’ proof for global warming

30.11.2004


A new interpretation for temperature data from satellites, published earlier this year, raised controversy when its authors claimed it eliminated doubt that, on average, the lower atmosphere is getting warmer as fast as the Earth’s surface.

Now, in another study headed by the same researcher to be published Dec. 15 in the Journal of Climate, direct temperature data from other scientists has validated the satellite interpretation. A team headed by Qiang Fu, a University of Washington atmospheric sciences associate professor, earlier examined measurements collected from January 1979 through December 2001 by devices called microwave-sounding units on National Oceanic and Atmospheric Administration satellites. Different channels of the microwave-sounding units measure radiation at different frequencies, providing data for different layers of the atmosphere.

In the case of the troposphere, the layer from the surface to an altitude of about 7.5 miles, where most weather occurs, it was believed there had been less warming than what was recorded at the surface. However, Fu’s team determined the satellite readings of the troposphere were imprecise because about one-fifth of the signal actually came from a higher atmosphere layer called the stratosphere, which for the last few decades has been cooling several times faster than the troposphere has been warming. The group devised a method to remove the stratosphere signal from the satellite data and was left with results that closely matched the warming at the surface. That work was published in May in the journal Nature.



However, critics contended the method overcompensated for the cooling effects of the stratosphere and thus overstated the amount of warming in the troposphere. The criticisms did not appear in peer-reviewed journals. In the new study, Fu and Celeste Johanson, a UW atmospheric sciences graduate student, used direct stratosphere temperature measurements to examine the contamination from the stratosphere in the satellite channel that measures troposphere temperatures. They also used the same data to evaluate their method for removing the stratosphere contamination. The data they used came from scientists at NOAA and the Hadley Centre for Climate Prediction and Research in England.

Using the direct stratosphere temperature trend profiles from 1979 through 2001, Fu’s team found that the stratosphere contamination in the satellite channel measuring the troposphere amounted to about a minus one-tenth of a degree Celsius per decade. They used their new method to remove the contamination, leaving an influence from the stratosphere of less than one-hundredth of a degree on troposphere temperature trends. The results match closely with what would be expected from the Fu team’s new interpretation of satellite data. "These results are consistent with the results that the Nature paper gets," Fu said. "It is an independent check of the problem because we used completely independent data sets. The independent observations agree with our conclusions, and that’s quite powerful evidence."

The Fu team’s work indicates the troposphere has been warming at about two-tenths of a degree Celsius, or nearly one-third of a degree Fahrenheit, per decade. That closely resembles measurements of warming at the surface, something climate models have suggested would result if the warmer surface temperatures are the result of greenhouse gases.

The findings are important because, for years, satellite data inconsistent with warming at the surface have fueled the debate about whether climate change is actually occurring.

If contamination of troposphere signals by those from the stratosphere isn’t taken into account for the last 25 years, Fu said, estimates of how much warming actually occurred in the troposphere during that time would be off by 40 percent to 70 percent.

Vince Stricherz | EurekAlert!
Further information:
http://www.washington.edu

More articles from Earth Sciences:

nachricht Six-decade-old space mystery solved with shoebox-sized satellite called a CubeSat
15.12.2017 | National Science Foundation

nachricht NSF-funded researchers find that ice sheet is dynamic and has repeatedly grown and shrunk
15.12.2017 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>