Temperature

Daily Trends

Climate	Cold Front Effect	Inversion Effect
to Energy & Heating	to Atmospheric Pressure	Return

Under clear, calm skies temperature rises after dawn, and peaks a few hours after peak insolation at noon. After sundown temperature declines throughout the night, reaching a daily minimum just before dawn.
Clouds alter the normal temperature progression, by shading during the day, and by enhanced heat trapping at night.
When clouds develop (here at 8:30 AM), the effect is to moderate the normal daily extremes.
Fronts are the leading boundary of an invading air mass. The invading air may be either warmer or colder.
When a front arrives, the normal temperature progression changes abruptly. Here a cold front arrives at 8:30 AM, causing a sudden drop in temperature.
Inversions are abnormally warm layers of air aloft. Being of unlike density, the inversion air does not mix readily with the cooler air below.
When an inversion develops (here at 8:30 AM), temperature in the underlying air continuously rises until the inversion "breaks". An inversion will not break until temperature of the underlying air equals the maximum temperature within the inversion layer.

Because inversions prevent vertical mixing, the underlying air often accumulates particulates and other pollutants. Below you can actually see the difference between the relatively clear inversion layer air above and the "dirty" air beneath it.

Climatic (long-term) Trends

Latitude

In the tropics (low latitude), temperatures are always high, and the daily range of temperature usually exceeds the annual range of temperature.
At high latitude temperatures are cooler, and the annual range of temperature generally exceeds the typical daily range of temperature.

Altitude

Temperature at lower altitude (or elevation) usually is warmer than at higher altitude.
The range of temperature, however, is usually about the same at low and high altitude.

Continentality

Temperatures in humid coastal areas usually are moderated; because of the diversion of much heat energy to keeping water vapor in the air, coastal locations do not experience either extreme heat or extreme cold.
Interior locations far from ocean moisture sources experience much greater temperature extremes. The lower humidity allows more heat energy for raising daytime temperatures, but also allows more rapid radiant heat loss at night.

Climate	Cold Front Effect	Inversion Effect
to Energy & Heating	to Atmospheric Pressure	Return

Yours is visit # to this Web page since 10MAY97.

N. C. Heywood maintains this page, last updated 20JUL99.