Day and Night(nocturnal) Energy Transfers
Table of Contents
These transfers occur on a local scale
Day energy transfers
Incoming solar radiation:Main source of energy from the sun in the form of shortwave length.Highest insolation occur around 2pm.
Reflected Solar Radiation:High albedo surfaces such as ice and clouds reflect more solar radiation resulting in less energy to the surface.
Surface absorption: Surfaces have different thermal capacities,concrete surfaces for example do not conduct heat to lower layers and results in high temperatures at the surface.Conversley soil tend to conduct heat to lower layers.
Sensible Heat Transfer:Movement of air parcels in and out of an area being observed.Cold air masses leave cold temperatures in their wake(path). Warm parcels of air rises by Convection into the atmosphere and can be replaced by subsiding cold air.
Latent Heat:Heat which changes state of a substance without altering its temperature.when you put an ice cube in your hand it melts due to heat released by your hand but the ice cube never gets hot.During the day heat is used to evaporate water rather than raising local temperatures.
Longwave Radiation:Outgoing radiation emited by earth’s surface.The radiation can be directed downwards by atmospheric gases.The difference between the outgoing from the surface and the downward from the atmosphere is the net radiation balance.
Outgoing Terrestial Radiation:During the night energy is radiated back to space.If there’s more cloud cover more radiation is trapped and retained in the lower layers,however on clear skies more energy is lost since there are no clouds to trap some of it.Maximum outgoing radiation is around 3am in the morning ,the ground will be completely cold.
Sub-surface Surface:The heat that was trapped by the surfaces is released back on top which can offset the the cooling of the surface.
Condensation:Air parcels loitering around the cold surface may condense to form dew and latent heat is released raising surface temperatures.
Sensible Heat :Cold parcels continue leaving cold temperatures and warm parcels leaving warm temperatures in their path.