diurnal variation


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Related to diurnal variation: diurnal variation of temperature

diurnal variation

[dī′ərn·əl ‚ver·ē′ā·shən]
(geophysics)
Daily variations of the earth's magnetic field at a given point on the surface, with both solar and lunar periods having their source in the horizontal movements of air in the ionosphere.
References in periodicals archive ?
The seasonality and diurnal variation of wind speed are observed by applying Fast Fourier Transform on NOAA wind data in New York and Austin.
(2011), pressure gradients in the plant, which are driven by diurnal variation in light availability, may produce variation on the C[H.sub.4] emissions according to the solar radiation.
The diurnal variation of aberrations was not significant, except ocular spherical aberration for 3 mm optical zone (P = 0.03).
The diurnal variation shows that the concentration of radon builds up at night when the ventilation in the houses is significantly reduced.
Then, mean diurnal variations (hourly averages binned over periods of 15 days) were used to fill residual gaps.
Diurnal variation of melatonin and sleep (% normal sleep, scored according to AASM standard, and % atypical sleep, scored according to Watson's classification) are presented in Figure 3.
Figure 1 shows the diurnal variations of [T.sub.a], [H.sub.r], and [S.sub.t] for a period of 24 h.
Beevers, "Diurnal variation of and activity during the onset of stroke," Neurosurgery, vol.
The relationship between diurnal variations in intraocular pressure measurements and central corneal thickness and corneal hysteresis.
The effect of diurnal variation on clinical measurement of serum testosterone and other sex hormone levels in men.
The urinary levels of 8-OHdG were low and lacked the diurnal variation in the younger age group in both controls and XPA patients (Figure 2(a)).