800 million years ago, there were significant glacial deposits in North America,
Australia, and Africa. At this time, paleomagnetism of rocks suggests that these
continents were near the south pole and that the equatorial Earth was largely
ocean.
LATITUDE
The higher the latitudes, the less solar radiation and, as a consequence, this
affects the climate.
LOCATION
Climate is influenced by the location of high and low air pressure zones and
where landmasses are distributed.
MOISTURE CONTENT OF AIR (HUMIDITY)
The moisture content of air is a primary determinant of plant growth and
distribution and is a major determinant of biome type (e.g., desert vs. tropical
forest). Atmospheric water vapor supplies moisture for clouds and rainfall, and it
plays a role in energy exchanges within the atmosphere. Water vapor is also a
greenhouse gas as it traps heat energy leaving Earth’s surface. The dew point is
the temperature at which the water vapor in the air (at constant barometric
pressure) condenses into liquid water at the same rate at which it evaporates. At
temperatures below the dew point, water will leave the air.
MOUNTAIN RANGES
The presence or absence of mountain ranges affects the climate. Mountains
influence whether one side of the mountain will receive rain or not (rain shadow
effect). The side facing the ocean is the windward side and receives the most
rain; the side of the mountain opposite the ocean is the leeward side and receives
little rain. Temperatures decrease as the altitude increases. Orographic lifting
occurs when an air mass is forced from a low elevation to a higher elevation as it
moves over rising terrain. As the air mass gains altitude, it expands and cools,
which can raise the relative humidity and create clouds and, under the right
conditions, precipitation.