Search results
Results from the WOW.Com Content Network
The Maine Geological Survey began a continuing process of mapping sand and gravel aquifers beginning in 1978. Statewide, Maine receives an annual rainfall total of 42 inches or 24 trillion gallons. Up to 50% of rainfall runs off the landscape in rivers and streams, while an additional 30–40% evaporates or is transpired through vegetation.
Atmospheric convection is the vertical transport of heat and moisture in the atmosphere.It occurs when warmer, less dense air rises, while cooler, denser air sinks. This process is driven by parcel-environment instability, meaning that a "parcel" of air is warmer and less dense than the surrounding environment at the same altitude.
The warm air overrides the cooler air and moves upward. Warm fronts are followed by extended periods of light rain and drizzle due to the fact that, after the warm air rises above the cooler air (which remains on the ground), it gradually cools due to the air's expansion while being lifted, which forms clouds and leads to precipitation.
Warm air has a lower density than cool air, so warm air rises within cooler air, [19] similar to hot air balloons. [20] Clouds form as relatively warmer air carrying moisture rises within cooler air. As the moist air rises, it cools, causing some of the water vapor in the rising packet of air to condense. [21]
Thus, hot air tends to rise and transfer heat upward. This is the process of convection. Convection comes to equilibrium when a parcel of air at a given altitude has the same density as its surroundings. Air is a poor conductor of heat, so a parcel of air will rise and fall without exchanging heat.
An elevated inversion layer is thus a region of warm air above a region of cold air, but higher in the atmosphere (generally not touching the surface). A capping inversion occurs when there is a boundary layer with a normal temperature profile (warm air rising into cooler air) and the layer above that is an inversion layer (cooler air below ...
The hot, rising air would then escape through windows near the ceiling to create a natural airflow. Architects also incorporated front porches onto houses to give homeowners some relief from the heat.
As warm, moist air rises up the windward side of a mountain, the air temperature cools and loses its capacity to hold moisture. Thus, the greatest amount of rainfall is expected at mid-altitudes and can support deciduous forest development. Above a certain elevation the rising air becomes too dry and cold, and thus discourages tree growth. [9]