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 ?
Annual variation in the local abundance of frugivorous birds customarily has been interpreted as a response to fluctuations in the abundance of fleshy fruits (e.
1996), but differences are difficult to interpret because of annual variation in size of litter (seigel and Fitch, 1985; Ford and seigel, 1989) and a general increase in size of litter with snout-vent length of mother (Ford and Killebrew, 1983; seigel and Ford, 1987).
Information about the annual variation of trichomoniasis in mourning doves (Zenaida macroura) may be important in understanding mechanisms affecting mourning dove populations.
As example of similar trends we can mention LAMA, BOGO, BOGI and JOZE horizontal velocity, ORID, BUCU and SOFI annual variation in dn component.
Elder interviews focused on themes such as (1) annual variation in body condition of caribou; (2) potential reasons for annual variation in caribou condition; (3) fat deposition sites on a caribou from which condition is assessed; (4) selection criteria for caribou based on season, gender, and age; and (5) geographic variation in caribou body condition.
Annual variation in elk (Cervus elaphus) social groups tends to be pronounced, particularly for herds that are migratory, heavily hunted, and/or subject to seasonal resource limitations (Knight, 1970; Shoesmith, 1979; Franklin and Lieb, 1979; Clutton-Brock et al.
2] concentration is steadily increasing with annual variation only up to ten parts per million.
Heterozygosity and inbreeding coefficients for cohorts vary concordantly with annual variation in nesting success and [Theta] indicating that factors underlying annual variation in reproductive success may also affect the degree of departure from random mating.
atmospheric) of nutrients and microorganism that drive biogeochemical processes in relation to annual variation in Arctic microbial activity and biogeochemical processes.
By being the youngest, smallest and arguably the weakest individuals in the population, we may also expect them to quickly respond to annual variation in living conditions (Gaillard et al.
92), the scientists have made a preliminary estimate that the annual variation in alpha, if any, must be less than 1 part in 100 trillion.

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