Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Research Brings Satellite Measurements and Global Climate Models Closer

09.05.2012
One popular climate record that shows a slower atmospheric warming trend than other studies contains a data calibration problem, and when the problem is corrected the results fall in line with other records and climate models, according to a new University of Washington study.

The finding is important because it helps confirm that models that simulate global warming agree with observations, said Stephen Po-Chedley, a UW graduate student in atmospheric sciences who wrote the paper with Qiang Fu, a UW professor of atmospheric sciences.

They identified a problem with the satellite temperature record put together by the University of Alabama in Huntsville. Researchers there were the first to release such a record, in 1989, and it has often been cited by climate change skeptics to cast doubt on models that show the impact of greenhouse gases on global warming.

In their paper, appearing this month in the American Meteorological Society’s Journal of Atmospheric and Oceanic Technology, Po-Chedley and Fu examined the record from the researchers in Alabama along with satellite temperature records that were subsequently developed by the National Oceanic and Atmospheric Administration and Remote Sensing Systems.

Scientists like Po-Chedley and Fu have been studying the three records because each comes to a different conclusion.

“There’s been a debate for many, many years about the different results but we didn’t know which had a problem,” Fu said. “This discovery reduces uncertainty, which is very important.”

When they applied their correction to the Alabama-Huntsville climate record for a UW-derived tropospheric temperature measurement, it effectively eliminated differences with the other studies.

Scientists already had noticed that there were issues with the way the Alabama researchers handled data from NOAA-9, one satellite that collected temperature data for a short time in the mid-1980s. But Po-Chedley and Fu are the first to offer a calculation related to the NOAA-9 data for adjusting the Alabama findings, said Kevin Trenberth, a distinguished senior scientist at the National Center for Atmospheric Research.

“It should therefore make for a better record, as long as UAH accepts it,” he said.

To come up with the correction, Po-Chedley and Fu closely examined the way the three teams interpreted readings from NOAA-9 and compared it to data collected from weather balloons about the temperature of the troposphere.

They found that the Alabama research incorrectly factors in the changing temperature of the NOAA-9 satellite itself and devised a method to estimate the impact on the Alabama trend.

Like how a baker might use an oven thermometer to gauge the true temperature of an oven and then adjust the oven dial accordingly, the researchers must adjust the temperature data collected by the satellites. That’s because the calibration of the instruments used to measure the Earth's temperature is different after the satellites are launched, and because the satellite readings are calibrated by the temperature of the satellite itself. The groups have each separately made their adjustments in part by comparing the satellite’s data to that of other satellites in service at the same time.

Once Po-Chedley and Fu apply the correction, the Alabama-Huntsville record shows 0.21 F warming per decade in the tropics since 1979, instead of its previous finding of 0.13 F warming. Surface measurements show the temperature of Earth in the tropics has increased by about 0.21 F per decade.

The Remote Sensing Systems and NOAA reports continue to reflect warming of the troposphere that’s close to the surface measurements, with warming of 0.26 F per decade and 0.33 F respectively.

The discrepancy among the records stems from challenges climate researchers face when using weather satellites to measure the temperature of the atmosphere. The records are a composite of over a dozen satellites launched since late 1978 that use microwaves to determine atmospheric temperature.

However, stitching together data collected by those satellites to discover how the climate has changed over time is a complicated matter. Other factors scientists must take into account include the satellite’s drift over time and differences in the instruments used to measure atmospheric temperature on board each satellite.

The temperature reports look largely at the troposphere, which stretches from the surface of the earth to around 10 miles above it, where most weather occurs. Climate models show that this region of the atmosphere will warm considerably due to greenhouse gas emissions. In fact, scientists expect that in some areas, such as over the tropics, the troposphere will warm faster than the surface of the Earth.

The paper does not resolve all the discrepancies among the records, and researchers will continue to look at ways to reconcile those conflicts.

“It will be interesting to see how these differences are resolved in the coming years,” Po-Chedley said.

The research was supported by the National Science Foundation and NOAA.

For more information: Po-Chedley, pochedls@atmos.uw.edu

Trenberth, trenbert@ucar.edu, 303.497.1318

Satellite temperature measurements FAQ: http://www.washington.edu/news/articles/satellite-temperature-measurements-faq

Nancy Gohring | Newswise Science News
Further information:
http://www.uw.edu

More articles from Earth Sciences:

nachricht In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

nachricht Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Comet or asteroid? Hubble discovers that a unique object is a binary

21.09.2017 | Physics and Astronomy

Cnidarians remotely control bacteria

21.09.2017 | Life Sciences

Monitoring the heart's mitochondria to predict cardiac arrest?

21.09.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>