Sentences with phrase «higher amplitude waves»

Westerlies don't reverse, but shift from Zonal Flow with few low amplitude Rossby Waves to Meridional Flow with more and higher amplitude Waves (Figure 3).

Not exact matches

«The greater, now, the strength of the movements of short period, the amplitude of the oscillations of the psycho - physical activity, the higher will the crests of the wavelets that represent them rise above, and the lower will their valleys sink below the surface of the under - wave that bears them.

Researchers have directly observed Alfvén waves in the lower corona, within about half a solar radius of the surface (SN: 4/11/09, p. 12), but not farther out where similar waves with higher amplitudes would travel.

However, a larger object requires higher - amplitude waves, so it might be a bumpy ride.

The model also generated acoustic data; an interesting revelation of the simulation was that tsunamigenic surface - breaking ruptures, like the 2011 earthquake, produce higher amplitude ocean acoustic waves than those that do not.

In their report, Laurent and his colleagues describe the existence of REM and slow - wave sleep in the Australian dragon, with many common features with mammalian sleep: a phase characterized by low frequency / high amplitude average brain activity and rare and bursty neuronal firing (slow - wave sleep); another characterized by awake - like brain activity and rapid eye movements.

Researchers have now built a working tractor beam that uses high - amplitude sound waves to generate an acoustic hologram which can pick up and move small objects.

Theta waves, with high amplitudes and frequencies falling between those of delta and alpha waves, normally appear in adults during light sleep and meditation.

By comparing that figure with the waves» amplitude at the source, which the researchers can derive from the shape of the signal, and by knowing how the amplitude decreases with distance, which they get from Einstein's theory, they can then calculate the distance of the source to a much higher precision.

A delta wave is a type of high amplitude brain wave found in humans.

The so - called K - complex — a single high - amplitude wave — occurred naturally, but it could also be made to appear whenever someone touched the sleeper's skin or made a soft noise.

A new study by Screen and Simmonds demonstrates the statistical connection between high - amplitude planetary waves in the atmosphere and extreme weather events on the ground.

Abstract: «Persistent episodes of extreme weather in the Northern Hemisphere summer have been shown to be associated with the presence of high - amplitude quasi-stationary atmospheric Rossby waves within a particular wavelength range (zonal wavenumber 6 — 8).

The equations for Rossby waves (Calculation of the Meridional Wave Number, Physics of the Parameter, and Calculation of the Amplitudes) show that this can occur if a set of necessary conditions are met: u ¯ > 0 in the midlatitude region; the highest value of l within the waveguide is in the range of the meridional wave numbers lm dominantly contributing to the external forcing with a given m, which provides closeness of the k waves to respective m waves not only in terms of the zonal but also the meridional wave numbers, favoring the QRA of the m waves; the total latitudinal width of the waveguide is no less than the characteristic spatial scale of the relevant Airy function (25), which is used as the boundary condition at its southern and northern boundaries; and latitudinal distribution of l is sufficiently smooth in the waveguide, and both TPs lie within a midlatitude region of ∼ 25 ° N — 30 ° N and ∼ 65 ° N − 70 ° N, as the necessary condition for the application of quasilinear Wentzel − Kramers − Brillouin (WKB) method (25) when solving the equations for Rossby waves.

Petoukhov et al. (34) proposed a common mechanism for generating persistent high - amplitude quasibarotropic planetary - scale wave patterns of the NH midlatitude atmospheric circulation with zonal wave numbers m = 6, 7, and 8 that can explain a number of the major NH summer extremes over the 1980 — 2011 period (34, 35).

Free extratropical Rossby waves with zonal wave numbers about 6 to 8 mostly occur as high - amplitude, fast traveling waves (the so - called synoptic transients responsible for much of the weather variability in the extratropics); once established, they can freely propagate predominantly to the east with a phase speed c ≈ 6 − 12 m ⋅ s − 1 without maintenance from external forcing.

These authors also presented an explanation for the emergence of these unusual high - amplitude wave patterns, namely that they were due to the mechanism of QRA of planetary waves.

This attests that the QRA, as described here in a quasilinear approximation, is not, of course, the only mechanism for generating regimes of high - amplitude midlatitude waves with m = 6, 7, and 8.

We further show that resonance conditions for these planetary waves were, in many cases, present before the onset of high - amplitude wave events, with a lead time up to 2 wk, suggesting that quasiresonant amplification (QRA) of these waves had occurred.

A strong snowmelt in late April / early May and torrential rains in late May / early June could have been caused by the occurrence of persistent quasibarotropic high - amplitude QRA structures with zonal wave numbers m = 6 and m = 7 in the field of the NH midlatitude meridional velocity.

However, using National Centers for Environmental Prediction − National Center for Atmospheric Research (NCEP - NCAR) reanalysis data (41), Petoukhov et al. (34) showed that, during a number of recent NH extremes in July and August, certain persistent high - amplitude atmospheric wave patterns with barotropic vertical structure evolved, to which the quasistationary component of midlatitude barotropic free waves with zonal wave numbers k ≈ 6 − 8 made an exceptionally large contribution.

On a related note, there has been a considerable amount of recent interest focused upon a possible increase in the frequency and / or intensity of high - amplitude atmospheric wave patterns (and associated extreme weather events) due to enhanced warming of the Arctic over the past 2 - 3 decades.