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Related:  April 27th 2011 Tornado OutbreakScienceIGB_intersting_articles

Monster Alabama Tornado Spawned by Rare "Perfect Storm" ON TV: Witness: Tornado Swarm 2011 airs Sunday, May 29, 9 p.m. ET/PT >> The monster tornado that devastated Tuscaloosa, Alabama, (see map) on April 27 was spawned by unusual "perfect storm" conditions, experts say. (See pictures of the Alabama tornado.) Those conditions—which stretched across Mississippi, Alabama, and Georgia—included warm, moist air rising and mixing with colder, dry air at higher altitudes. Unfortunately for those living in the tornadoes' path, "weather conditions came together perfectly," said Tim Samaras, a Denver, Colorado-based tornado expert and producer of the tornado-research website TWISTEX. "Mississippi, Alabama, and Georgia had that down to a T. Upper-level winds known as the jet stream also caused the storm system to rotate, according to meteorologist Jeff Masters, director of the website Weather Underground. Rotating thunderstorms—known as super cells—spawn tornadoes. "This is a history-making tornado outbreak," Masters said. Stormy Spring Still a Mystery

La sfera celeste - Osservare il Cielo - Sezione di Didattica » Osservatorio Astronomico Comunale di Acquaviva (BARI) - ITALY Solo fino a qualche secolo fa il cielo era pensato come una enorme sfera concentrica alla Terra, che ruotava intorno a essa. Le stelle erano considerate come "gemme" fisse, incastonate sulla "sfera celeste", la cui posizione era ritenuta immutabile nel tempo. I pianeti, invece, si distinguevano dalle prime per il fatto di muoversi percorrendo delle traiettorie "complesse" (pianeta infatti significa "corpo errante"). Soltanto dal secolo scorso sappiamo che l'Universo ? ben diverso dal cielo perfetto e immutabile di Aristotele. Le stelle sono tutt'altro che immobili, e sembrano fisse solo a causa della enorme distanza che ci separa da esse, che rende impossibile qualsiasi percezione prospettica di movimento. Definiamo pertanto sfera celeste (fig. 1) una superficie sferica infinitamente grande e concentrica alla Terra. L'intersezione dell'asse di rotazione terrestre con la sfera celeste individua il polo NORD e il polo SUD celeste. CASI PARTICOLARI. UN PO' DI GEOMETRIA.

It’s time for science to abandon the term ‘statistically significant’ | Aeon Essays The aim of science is to establish facts, as accurately as possible. It is therefore crucially important to determine whether an observed phenomenon is real, or whether it’s the result of pure chance. If you declare that you’ve discovered something when in fact it’s just random, that’s called a false discovery or a false positive. And false positives are alarmingly common in some areas of medical science. In 2005, the epidemiologist John Ioannidis at Stanford caused a storm when he wrote the paper ‘Why Most Published Research Findings Are False’, focusing on results in certain areas of biomedicine. The problem of how to distinguish a genuine observation from random chance is a very old one. What matters to a scientific observer is how often you’ll be wrong if you claim that an effect is real, rather than being merely random. Tests of statistical significance proceed by calculating the probability of making our observations (or the more extreme ones) if there were no real effect.

Magnitudes of impact - AR4 WGII Summary for Policymakers Magnitudes of impact can now be estimated more systematically for a range of possible increases in global average temperature. Since the IPCC Third Assessment, many additional studies, particularly in regions that previously had been little researched, have enabled a more systematic understanding of how the timing and magnitude of impacts may be affected by changes in climate and sea level associated with differing amounts and rates of change in global average temperature. Examples of this new information are presented in Figure SPM.2. Key impacts as a function of increasing global average temperature change (Impacts will vary by extent of adaptation, rate of temperature change, and socio-economic pathway) Figure SPM.2. The ‘reasons for concern’ identified in the Third Assessment remain a viable framework for considering key vulnerabilities. Impacts due to altered frequencies and intensities of extreme weather, climate and sea-level events are very likely to change. Table SPM.1.

The efficacy of calibrating hydrologic model using remotely sensed evapotranspiration and soil moisture for streamflow prediction a Department of Infrastructure Engineering, The University of Melbourne, Parkville, Victoria 3010, Australiab CSIRO Land and Water, P.O. Box 1666, Canberra, ACT 2601, Australiac Integrated Water and Land Management Program, ICARDA, P.O. Box 2416, Cairo, Egypt Received 7 September 2015, Revised 8 February 2016, Accepted 11 February 2016, Available online 22 February 2016 This manuscript was handled by Tim R. McVicar, Editor-in-Chief, with the assistance of Di Long, Associate Editor Choose an option to locate/access this article: Check if you have access through your login credentials or your institution Check access doi:10.1016/j.jhydrol.2016.02.018 Get rights and content Highlights Remotely sensed evapotranspiration (ET) and soil moisture (SM) are used for hydrologic model calibration. Efficacy of each of calibration is assessed by the improvement in streamflow predictions. Calibration performs well in catchments with high average runoff. Summary Keywords Copyright © 2016 Elsevier B.V.

Alabama tornado anniversary: Study shows victims heeded warnings STR / Reuters An aerial view shows extensive damage to homes and businesses in the path of tornadoes in Tuscaloosa, Alabama, on April 28. By Mike Stobbe, The Associated Press ATLANTA -- Most of the victims of last year's epic tornado outbreak in Alabama had at least one thing in common: They knew the storm was coming. A year after the onslaught of dozens of twisters killed at least 250 people in Alabama and more elsewhere in the South, federal researchers are completing a study of who died and where they were when it happened. But many of the tornadoes were so fierce that few structures were able to withstand them. These were catastrophic winds that could destroy pretty much anything in its path," Cindy Chiu, an epidemic intelligence service officer, said in reporting preliminary findings this month at a Centers for Disease Control and Prevention conference in Atlanta. While many who heard the warnings sought shelter, others took their chances and lost.

Definizioni di zenith, nadir, e azimuth : Astronomia Lo Zenit, anche detto Zenith, è l'intersezione della perpendicolare all'orizzonte passante per l'osservatore con l'emisfero celeste visibile ed è quindi il punto sopra la testa dell'osservatore. Il punto diametralmente opposto è detto Nadir. Zenit e Nadir sono i poli dell'orizzonte. L'azimut (o azimuth) è la distanza angolare di un punto dalla direzione del Nord, al punto in cui la perpendicolare calata di un punto (stella) incontra l' orizzonte, calcolata muovendosi in senso orario. È un termine usato prevalentemente in astronomia e in aeronautica e deriva dall'arabo as-samt (la direzione) o dal suo plurale as-sumut (le direzioni).

Lies, Damned Lies, and Medical Science - David H. Freedman In 2001, rumors were circulating in Greek hospitals that surgery residents, eager to rack up scalpel time, were falsely diagnosing hapless Albanian immigrants with appendicitis. At the University of Ioannina medical school’s teaching hospital, a newly minted doctor named Athina Tatsioni was discussing the rumors with colleagues when a professor who had overheard asked her if she’d like to try to prove whether they were true—he seemed to be almost daring her. She accepted the challenge and, with the professor’s and other colleagues’ help, eventually produced a formal study showing that, for whatever reason, the appendices removed from patients with Albanian names in six Greek hospitals were more than three times as likely to be perfectly healthy as those removed from patients with Greek names. “It was hard to find a journal willing to publish it, but we did,” recalls Tatsioni. “I also discovered that I really liked research.” That question has been central to Ioannidis’s career.

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