But the weather-climate dichotomy paints an incomplete picture – one that may be complicating efforts to untangle natural variations in climate from man-made effects, according to McGill University physics professor Shaun Lovejoy.
In a paper published recently in the journal Eos, Transactions, American Geophysical Union, and in a forthcoming book, Lovejoy argues that statistical analysis shows there is a period between short-term weather and long-term climate that should be recognized as distinct.
Using the three-part atmospheric regime also makes the challenge of climate modeling more precise, and could open up a new set of approaches for modeling and predicting the climate, Lovejoy says.
Lovejoy used a new kind of "fluctuation analysis" to show that there are three atmospheric regimes, each with different types of variability. Between the weather (periods less than 10 days) and the climate (periods longer than about 30 to 100 years), there is an intermediate "macroweather" regime. A graphic representation makes the case intuitively clear.
The accompanying chart shows examples from weather (one-hour resolution, bottom), macroweather (20 days, middle) and climate (one century, top). The daily and annual cycles were removed and 720 consecutive points from each resolution are shown so that the differences in the characters of each regime are visually obvious.
At the bottom, the weather curve "wanders" up or down in a path resembling a drunkard's walk. In the middle, the macroweather curve has a markedly different character: upward fluctuations are typically followed by nearly cancelling downward ones. "The longer the period over which we average it, the smaller the variations become," Lovejoy says.
By contrast, the century scale climate curve (top) displays again a weather-like, wandering variability. (While this plot shows temperatures, other atmospheric fields – including wind, humidity and precipitation -- are similar.)
Although the ultimate implications of macroweather may not be known for some time, a basic change in our understanding of what climate is will surely have repercussions, Lovejoy notes.
"Macroweather clarifies the distinction between natural and anthropogenic types of variability and allows us to separate the two with more confidence."The old saying that "climate is what you expect, weather is what you get," also needs to be reconsidered, he adds. "Macroweather is what we expect."
Chris Chipello | EurekAlert!
Interstellar seeds could create oases of life
28.08.2015 | Harvard-Smithsonian Center for Astrophysics
Draw out of the predicted interatomic force
28.08.2015 | Hiroshima University
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.
These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...
Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.
For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...
It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.
Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
28.08.2015 | Physics and Astronomy
28.08.2015 | Health and Medicine
28.08.2015 | Life Sciences