Posted BY: Mark C. Ross
For the record, climate change is real — but that’s nothing new, just ask a wooly mammoth or a dinosaur. Atmospheric heat-trapping is also real, or else everything around us would freeze solid every night — just as it does on our airless moon. And sea level is the best way to tell if the earth is warming or cooling because it is a truly global indicator, rather than a stew of various local measurements.
It is also important to understand the well-known cycles that bring us seasons and weather patterns. The seasons change from equinox to solstice over and over because the earth’s rotational axis is tilted relative to its orbital plane. During winter in the northern hemisphere, the sun appears in the sky farther in the south. It moves north until it reaches the summer solstice — as the weather warms. Due to the elliptical nature of our orbit around the sun, the northern summer finds the earth farther away from its heat source than it is in the winter, which tends to moderate the seasonal temperature change.
The opposite is true for the southern hemisphere. Closer to the sun in the summer and farther in the winter would make for more severe weather down there, except for the much greater amount of the southern surface being covered by oceans, which also serve to moderate the weather.