annual variation


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Related to annual variation: seasonal variation

annual variation

[′an·yə·wəl ver·ē′ā·shən]
(astronomy)
The change in the right ascension and declination of a star during one year, due to the combined effect of the star's proper motion and the precession of the equinoxes.
(geophysics)
A component in the change with time in the earth's magnetic field at a specified location that has a period of 1 year.

annual variation

The quantum of yearly change in variation at a place. This is normally indicated on the bottom of a map or chart and must be added/subtracted to/from the figure given on the map after taking into consideration the number of years elapsed since the last survey for the map. Variation is the angular difference between the direction of true north and magnetic north at any given point.
References in periodicals archive ?
The indexation mechanisms and the increase in the persistence of inflation were reflected in the increase of the annual variation of non-tradable prices, and could delay convergence of inflation to its 3.
Also, the annual variation is significantover some oceans around islands in the Pacific Ocean.
2001), but have not described the annual variation in diet or food resources.
Environmental Annual variations of rainfall and temperature and humidity on Aus, Aman and Boro production is depicted on figure 1.
Parameters of nighttime and daytime temperatures were predictive in this model; the annual variation (amplitude) and the mean absolute temperature values scored high in the ranking.
The isotope values recorded in tree rings were very closely related to annual variation in the river levels of the Amazon, and thus of the amount of rainfall that flows into the ocean.
However for most species, little is known of the specific causes of annual variation in ASRs and the impacts they have on population dynamics (Le Galliard et al.
The findings of the study showed a clear annual variation in the decay rate of a radioactive isotope called chlorine 36, with the highest rate in January and February and the lowest rate in July and August, over a period from July 2005 to June 2011.
The influences of seawater temperature and sunshine duration on the annual variation in the timing of coral spawning were examined.
Hence, it was with the goal of quantifying and understanding the basis of annual variation in reproductive traits of bullsnakes (Pituophis catenifer sayi) that this study was undertaken.
Up to September 2011, the average inflation rate, measured by annual variation in the Consumer Price Index (CPI) for the Sultanate, stood higher at 4.

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