|
It is easy to understand how climate can vary over very large areas,
because of slight changes in temperature or rainfall. Climates can also
vary over very short distances. Local differences in climate are described
by the term "microclimate." Low-lying areas are often colder
at night than higher ground nearby. On clear nights, the ground is chilled
as its heat is radiated out to space. The cold ground then chills the
air near the ground. The chilled air is slightly denser than the overlying
air, so it tends to flow slowly downhill, in the same way that water flows
downhill. The cold air "ponds" in low areas. These are places
where the first frosts of autumn are earliest and where the last frosts
of spring are latest. If you ever have a chance to plant fruit trees,
plant them on the highest ground around!
In hilly areas, north-facing slopes get less sunshine than south-facing
slopes. Local temperatures on the north-facing slopes are colder than
on south-facing slopes in both summer and winter. In areas with winter
snows, the snow melts much later north-facing slopes.
Back To Top
|
