Suppose yesterday morning you noticed ice crystals (frost) on the grass, yet the minimum temperature reported in the newspaper was only $$35^{O} F$$. The most likely reason for this apparent discrepancy is that:
A
The thermometer was in error
B
The newspaper reported the wrong temperature
C
The thermometer was read before the minimum temperature was reached for that day
D
Temperature readings are taken in instrument shelters more than 5 feet above the ground
Correct option is A. Temperature readings are taken in instrument shelters more than 5 feet above the ground
$$\textbf{Correct option:}$$ $$\textbf{(A)}$$
$$\textbf{Solution:}$$
$$\bullet$$ The ability of the air to contain water as a vapour, which is temperature dependant, causes the production of ice crystals near the ground surface.
$$\bullet$$ If water vapour is cooled under constant pressure, the dew point temperature is the factor that causes it to condense and transform into dew, fog, or clouds.
$$\bullet$$ Temperature measurements should be taken in a concrete slab-mounted instrument shelter.
$$\bullet$$ The thermograph, maximum and minimum thermometers, soil temperature sensor, dry and wet bulb thermometers, and an aspirating motor are all contained within the weather shelter.
$$\textbf{Thus the Correct option is (A)}$$