(Press-News.org) The ionosphere, one of the regions of the upper atmosphere, plays an important role in global communications. Ionized by solar radiation, this electricity-rich region is used for the transmission of long wave communications, such as radio waves. Now Prof. Colin Price of Tel Aviv University's Department of Geophysical, Atmospheric and Planetary Sciences, working alongside PhD candidate Israel Silber, has discovered that the radio waves reflecting back to Earth from the ionosphere offer valuable news on climate change as well.
Their research shows that the strength of radio signals on the ground is a reliable indicator of temperature change above. Prof. Price and his team used simple radio antennae on the ground to measure radio waves broadcast by navigational transmitters around the globe, then compared information on the strength of these radio signals with data on temperature fluctuations in the upper atmosphere. They discovered that climate change in the upper atmosphere — caused by an abundance of greenhouse gases — may lead to a greater absorption of radio waves. Weaker signals could therefore be indicative of greater climate change.
Detailed in the Journal of Geophysical Research, this simple, cost-effective measurement can be a valuable contribution to the ongoing effort to track climate change, says Prof. Price, adding to measurements of ground and lower atmospheric temperatures to create a more holistic picture.
Global warming, upper atmospheric cooling
On the Earth's surface and in the lower atmosphere, an increase of greenhouse gases has a warming effect, the gases acting as a "blanket" and keeping heat from escaping from the Earth into space. But these gases, including carbon dioxide, are increasing in the upper atmosphere as well, where they have a cooling effect.
When cooled, the ionosphere contracts and descends into the atmosphere to where air is denser – leading to a higher absorption of radio waves, Prof. Price explains. By examining satellite-gathered data on the temperature in the upper atmosphere and comparing results to measurements of radio wave amplitudes collected on the ground, the researchers were able to uncover a clear correlation, consistent over time. As the upper atmosphere gets colder, radio signals lose their strength.
While the sun is certainly the driving force behind changes in temperature in this region, it accounts for only 60 to 70 percent of temperature variations, says Prof. Price. The remaining variability could not be systematically measured until now. By adding measurements of radio waves taken on the ground to solar radiation estimates, researchers can now explain approximately 95 percent of temperature changes in the upper atmosphere.
Degrees of change
According to Prof. Price, this new technique will be a valuable addition to current methods of monitoring climate change, such as the measurement of ground temperatures. Without the need for expensive equipment like satellites, monitoring the upper atmosphere can be done inexpensively and continuously. And because temperatures in the upper atmosphere fluctuate more dramatically than those on the ground — for every one degree of warming in the lower atmosphere, there is a corresponding ten degree cooling in the upper atmosphere — changes are far easier to monitor.
Using this system might reveal more about the ionosphere than ever before. The region is notoriously difficult to monitor; there are no weather balloons or airplanes that can go high enough, and it is too low for orbiting satellites. But with this method, it could be possible to study long and short term changes in the ionosphere, such as the impact of solar storms or thunderstorms on the upper atmosphere.
###
American Friends of Tel Aviv University supports Israel's leading, most comprehensive and most sought-after center of higher learning. Independently ranked 94th among the world's top universities for the impact of its research, TAU's innovations and discoveries are cited more often by the global scientific community than all but 10 other universities.
Internationally recognized for the scope and groundbreaking nature of its research and scholarship, Tel Aviv University consistently produces work with profound implications for the future.
Radio waves carry news of climate change
Tel Aviv University researcher develops surprising tool to measure our changing climate
2013-07-30
ELSE PRESS RELEASES FROM THIS DATE:
Fat digestibility in pigs study looks at oils in soybeans, corn co-products
2013-07-30
URBANA. Ill. – Pork producers need accurate information on the energy value of fat in feed ingredients to ensure that diets are formulated economically and in a way that maximizes pork fat quality. Researchers at the University of Illinois have determined the true ileal and total tract digestibility of fat in four corn co-products, as well as in full fat soybeans and corn oil.
Hans H. Stein, a professor of animal sciences at U of I, led the team of researchers in the study in which they looked at four corn co-products: distillers dried grains with solubles (DDGS), high-protein ...
'Cowcatcher' enzyme fixes single-strand DNA
2013-07-30
Every time one of your cells divides, it exposes its most essential component to great danger: its genome, the sum total of all its genetic information, embodied in the double-stranded helix of DNA. Prior to cell division, this DNA splits into two single strands, each bearing sequences of biochemical bases that form templates for the genomes of the daughter cells. These single strands are particularly vulnerable to assaults by reactive oxygen species — toxic byproducts of respiration — that could cause changes in the genetic information they contain.
Left unchecked, ...
How does hydrogen metallize?
2013-07-30
Washington, D.C.— Hydrogen is deceptively simple. It has only a single electron per atom, but it powers the sun and forms the majority of the observed universe. As such, it is naturally exposed to the entire range of pressures and temperatures available in the whole cosmos. But researchers are still struggling to understand even basic aspects of its various forms under high-pressure conditions.
Experimental difficulties contribute to the lack of knowledge about hydrogen's forms. The containment of hydrogen at high pressures and the competition between its many similar ...
Aberrant splicing saps the strength of 'slow' muscle fibers
2013-07-30
HOUSTON (July 29, 3013) – When you sprint, the "fast" muscle fibers give you that winning kick. In a marathon or just day-to-day activity, however, the "slow," or type 1 fibers, keep you going for hours.
In people with myotonic dystrophy, the second most common form of muscular dystrophy and the one most likely to occur in adults, these slow or type 1 fibers do not work well, wasting away as the genetic disorder takes its grim toll. In a report that appears online in the Proceedings of the National Academy of Sciences, Dr. Thomas A. Cooper, professor of pathology & immunology ...
Decision aids reduce men's conflict about PSA screening, but don't change their decisions
2013-07-30
WASHINGTON – Men who decide to be screened for prostate cancer and those who forgo PSA screening stick with their decisions after receiving materials explaining the risks and benefits of the test. The decision aids greatly increased their knowledge about screening and reduced their conflict about what to do, but did not have an impact on their screening decision when measured a year later.
That's the finding of a new study published today in JAMA Internal Medicine that examined both web-based and printed tools aimed at helping men make informed decisions about PSA testing.
In ...
Playing college football linked with high blood pressure risk
2013-07-30
College football players, especially linemen, may develop high blood pressure over the course of their first season, according to a small study in the American Heart Association's journal Circulation.
Researchers documented higher blood pressure levels among 113 first-year college players. Only one player had already been diagnosed with hypertension before the season and 27 percent had a family history of hypertension. At post-season, researchers noted:
47 percent of players were considered pre-hypertensive, while
14 percent had stage 1 hypertension.
While previous ...
Treatment for back pain varies despite published clinical guidelines
2013-07-30
Management of back pain appears to be variable, despite numerous published clinical guidelines, according to a report published by JAMA Internal Medicine, a JAMA Network publication.
Spinal symptoms are among the most common reasons patients visit a physician and more than 10 percent of visits to primary care physicians relate to back and neck pain, the authors write in the study background.
John N. Mafi, M.D., of Harvard Medical School, Boston, and colleagues used nationally representative data from the National Ambulatory Medical Care Survey and the National Hospital ...
Adolescent kidney transplant recipients appear to be at higher risk of transplant failure
2013-07-30
Patients who received their first kidney transplant at ages 14 to 16 years appear to be at increased risk for transplant failure, with black adolescents having a disproportionately higher risk of graft failure, according to a report published by JAMA Internal Medicine, a JAMA Network publication.
Existing medical literature does not adequately describe the risks of graft failure among kidney transplant recipients by age. Organ losses by adolescents are partly due to physiologic or immunologic changes with age but psychological and sociological factors play a role, especially ...
Decision aids associated with increase in informed decision making about prostate cancer screening
2013-07-30
Both web-based and print-based decision aids appear to improve patients' informed decision making about prostate cancer screening up to 13 months later, but does not appear to affect actual screening rates, according to a study by Kathryn L. Taylor, Ph.D., of Georgetown University, Washington, D.C., and colleagues.
A total of 1,893 men participated in the study, with 628 men randomly given a print-decision aid, 625 men used a web-based interactive decision aid, and 626 men received usual care. Researchers measured the participants' prostate cancer knowledge, decisional ...
Breastfeeding duration appears associated with intelligence later in life
2013-07-30
Breastfeeding longer is associated with better receptive language at 3 years of age and verbal and nonverbal intelligence at age 7 years, according to a study published by JAMA Pediatrics, a JAMA Network publication.
Evidence supports the relationship between breastfeeding and health benefits in infancy, but the extent to which breastfeeding leads to better cognitive development is less certain, according to the study background.
Mandy B. Belfort, M.D., M.P.H., of Boston Children's Hospital, and colleagues examined the relationships of breastfeeding duration and exclusivity ...
LAST 30 PRESS RELEASES:
Study finds restoring order to dividing cancer cells may prevent metastasis
High-accuracy tumor detection with label-free microscopy and neural networks
Wayne State research reveals fetuses exposed to Zika virus have long-term immune challenges
Researchers deconstruct chikungunya outbreaks to improve prediction and vaccine development
Study finds one-year change on CT scans linked to future outcomes in fibrotic lung disease
Discovery of a novel intracellular trafficking pathway in plant cells
New tool helps forecast volcano slope collapses and tsunamis
Molecular coating cleans up noisy quantum light
From Parkinson's to rare diseases, discovered a key switch for cellular health
Tiny sugars in the brain disrupt emotional circuits, fueling depression
Mini-organs reveal how the cervix defends itself
Africa, climate, and food: How to feed a continent without increasing its carbon footprint
Researchers demonstrates substrate design principles for scalable superconducting quantum materials
How better software choices could cut US health care costs
Concussion history in NCAA athletes yields mixed health outcomes
Counting plastic reveals hidden waste and sparks action
Warming oceans may pose a serious threat to American lobsters
Deaths from drug-induced unintentional injury rise across the US
In car crashes with pedestrians, age and zip code may predict extent of traumatic injuries
AI optimizes evacuation, diagnosis, and treatment of wounded soldiers in Ukraine
Mastectomy linked to worsened sexual health, body image after surgery
Drop in credit score after cancer diagnosis linked to increased mortality, study shows
Use of weight loss drugs before bariatric surgery has soared in recent years, study finds
EMS call times in rural areas take at least 20 minutes longer than national average
Rectal bleeding in young adults linked to 8.5 times higher risk of colorectal cancer
Hospital closures disproportionately affect socioeconomically disadvantaged communities
Global disparities in premature mortality
Keck Medicine of USC expands world-class care in Pasadena
Untreated depression makes surgical outcomes worse in cancer patients
Standardizing frailty indexes to improve preclinical aging research
[Press-News.org] Radio waves carry news of climate changeTel Aviv University researcher develops surprising tool to measure our changing climate