Weight Variation by Latitude
Weight Variation by Latitude refers to the claims that scales have measured masses to be slightly more or less at different points on earth. It is asserted that, due to a combination of the centrifugal effect and the further distance from the center of mass, bodies will weigh less at the equator than the poles.
Upon assessment of the experiments supporting this, it is found that these experiments are always conducted with the scale and body exposed to the surrounding atmosphere. A scale is calibrated for one area and then taken to another area, uncalibrated. Measures are not taken to isolate the test body and the measuring device from the influences of the environmental atmosphere. It is known that pressure and humidity affects scales. It is also known that that pressure is greater at the poles and lesser at the equator. It is further known that pressure is greater at lower altitudes near sea level and lesser at higher altitudes—the same general relationship the weight changes are said to occur. Humidity likewise has a relationship with between altitudes and latitudes.
Andrew Huszczuk, Ph.D. writes:
“ Would you take a medication knowing that a pharmacy used an uncalibrated scale to weigh its ingredients? Would you board a plane knowing that the fuel or altitude gauges are not calibrated at frequent intervals?
In these and thousands of other applications scientific bases and rules of metrology must be obeyed to assure chaos-free operation of modern societies. To scrutinize performance of measuring devices a process of calibration must be carried out by means of applying a known standard and getting back a correct reading. ”
Scales Affected by Atmosphere
One precision scale manufacture lists many factors which can affect a scale:
https://www.arlynscales.com/scale-knowledge/factors-can-affect-scales-accuracy/
“ Factors That Can Affect Your Scale’s Accuracy
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Differences in air pressure – Scales can provide inaccurate measurements if the air pressure from the calibration environment is different than the operating environment. ”
If the air pressure from the calibration environment is different than the operating environment, it will effect the scale. Also mentioned on the page are temperature and humidity which can affect the operation of a precision scale.