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To some, winter is simply a season to get through, for others it’s a time
for fun and frolics on snow-covered slopes. But what causes winter? Seasonal
changes are the result of the earth’s once-a-year orbit around the sun
together with the tilt of the earth’s axis. Winter is not the effect of the
earth moving further from the sun, as many people believe. The fact is that
winter arrives when the sun is at its closest to the earth. But our earth
tilts at over 23°, resulting in a variation in the distance between parts of
the earth’s surface and the sun during the path of the earth’s orbit. In
winter, the northern hemisphere is tilted away from the sun and the rays
glancing off the earth at a lower angle emit less energy and thus
temperatures are lower. Conversely the southern hemisphere will be tilted
towards the sun, is thus exposed to more direct sunlight and experiences
increased temperatures. The seasons in the two hemispheres are always
opposite to each other. When the northern hemisphere is enjoying summer, the
southern hemisphere is in the grip of winter and vice versa. |
