Why Winter is Cold and Summer is Hot

Ever wonder why there is snow and cold weather in the winter and steamy hot weather in the summer. OK, I am sure that most of you already know it has something to do with the days getting shorter during winter and longer during summer. A short day means less sunlight. Less sunlight means less heat. Well, that actually does not explain winter. Lets say that the summer's heat is the result of long days. An average summer temperature is around 80°. The longest summer day outside the arctic circle is about 16 hours, or two thirds the 24 hour day cycle in sunlight and one third in darkness. In winter the shortest day is about 10 hours of sunlight, which is two hours more than one third of the day in sunlight. If two thirds a day's sunlight in the summer gives you 80° then half of that, or one third a day, would give you 40 degrees. So because a winter day is two hours longer than a third day then we should be getting no less than 40 degrees. So where does the below freezing weather come from if the only explanation of winter weather is shorter days?

Now here is something else that puts a huge hole in the shorter-day theory. The shortest day of the year is December 21 after which the days gradually grow longer. The longest day of the year is June 21 after which days get shorter. Well that does not make sense, does it. We all know when the seasons are. June 21 is the first day of summer and December 21st is the first day of winter. Prior to summer is spring, usually warm, occasionally cold, but rarely hot. It is after June that the hot weather of July and August begins. This is followed by fall which does not begin until September. October, November and December are cool with occasional warm spells called Indian summers, but rarely ever frigid. The frigid weather and most of the snow does not begin until Winter, which is late December, January, February, and March. So if the day is getting longer after December 21 then it should be getting warmer, not colder, right? And the opposite should be true for summer, right?

Well, that is why they call it weather. The name was derived from the phrase "whether or not", as in "Whether or not it will rain tomorrow" or "Whether or not it will be warm tomorrow". Scientist figured out early on that we get weather from traveling air masses. Rain comes from elsewhere. If it was simply condensation from evaporating water them clouds would form over ponds, lakes, and oceans and stay there until they caused rain instead of traveling overhead. We get things like wind which drags air from elsewhere. If the wind comes from the south then we get their warm air, from the north then we get their cold air. If air masses did not travel then hurricanes would stay out in the ocean where they form instead of racing up the coast. The key to winter and summer is that in both seasons we are getting cold or hot air from elsewhere. And yes, it does have something to do with the length of the day, but just not locally.

First, lets look at what causes long days in summer and short days in winter. The Earth is a spinning ball. The side of the ball facing the sun gets daylight. When the spin causes that side to face away from the sun then it gets night. The Earth also spins at an angle so that the during the winter the bottom half is angled at the sun while the top of the Earth is angled away from the sun. In other words during the winter the North Pole is pointed away from the sun and is in complete darkness. Once beyond the arctic circle winter days can be very short or even non existent. A night can last nearly three months before the sun returns. On the other end of the earth the South Pole is pointed towards the sun and the opposite is happening. It is getting three days of sunlight with no nighttime. As the Earth revolves around the sun the angles switch so that for Summer the North Pole is pointed at the Sun and is getting three months of unbroken sunlight while the South Pole is completely in the dark. For the rest of us it is shorter or longer days. When we are getting winter in the North on the South end of the planet is getting summer. When they get their winter we are getting our summer. For those living in the center of the world there is no seasons, just one long unbroken summer that lasts all year long.

Now let take into consideration two things, the North Pole being pointed away from the sun during the winter and weather dragging air masses from elsewhere. Because the North Pole is freezing this time of the year the air that flows out of it is freezing. Think of the North Pole as a powerful air conditioner. Now think of the eternal summer of the center of the Earth as our planet's radiator. The radiator is pretty strong, creating days as hot as 120°. It is now a question as to how much South heat we are getting vs. how much cold air the Northern air conditioner is giving off. Since the long night of the North Pole begins in November and does not end until late January then even though we are getting longer days in the winter the North Pole is still in darkness. Once the darkness begins lack of sunlight causes the North to gradually freeze. It is still loosing heat after December 21st and by the time sunlight finally comes to the North Pole it would be at it's coldest. Because the North Pole is still getting colder after December 21st it is becoming more of an effective air conditioner even as the days are growing longer. By the end of January it is going full blast counteracting any heat coming from the South. Then summer comes and for three weeks it is nothing but sunlight. The North Pole is so cold that even with three months of sunlight in the summer it is not enough to warm the place up beyond the 60° mark. Still, it is no longer cold enough to counteract the heat from the South. By mid August the North Pole's long day finally comes to an end and is now at it's warmest. Finally, as it begins to get nighttime it begins to cool off. This is why the frigid and hot weather seems to lag behind the longest and shortest days.