....temperatures still get colder on average until end of January? I would think since the sun is moving back towards the equator, the days would on average start to get warmer right away.
2006-12-21 11:33:28 · 7 answers · asked by Greenwood 5 in Science & Mathematics ➔ Weather
The reason why the temperature remains low is because the water from the ocean, rivers, lakes and water everywhere else on/in the earth such as the ground, take a long time to warm up. (it takes more energy to warm up water than to warm up air, so water temp affects air more than air temp affects water)
As the sun starts to shine longer and stronger, it warms up the air, but the water cools the air down. (this is why some farmers spray their crops with water when there is a predicted frost. the water sprayed over the crops will 'absorb' the coldness of the air and prevent the leaves of the crops from freezing up (the more water, the more energy or lack of energy needed to affect the temp of the water)
So when the sun begins to warm up the land after the solstice, the bodies of water on earth absorb the heat. When the summer solstice passess the land becomes colder only after a month or so because the now warm water gives off its energy to the land.
hope this helps! =)
2006-12-21 11:54:39 · answer #1 · answered by odonata 2 · 1⤊ 1⤋
The temperatures still get colder because the sun is not warming up the northern hemisphere fast enough. The arctic air masses have had several months to get cold and they continue to move down toward the southern part of the United States. Also, the jet stream plays a major part in bringing these arctic air masses down to lower latitudes. In other words there is a delay of seasons. Meteorologists like to break up the seasons in to three based on temperatures alone. The astronomical measurement is what we use to determine the four seasons that we have today. Basically, there is a lot of complicated physics involved.
2006-12-21 13:27:50 · answer #2 · answered by Weather Facts 2 · 1⤊ 0⤋
I think its due to the fact that much of the surface of the earth is covered in water and water has a high thermal capacitance. This means it takes a long time to change the temperature of water, whether you're cooling it down or heating it up. Although the days will start getting longer in the north, its a slow process and the water is just starting to freeze over (northern pacific, and arctic oceans). Cold waters make cold air and the sun won't be strong enough to start heating the northern waters for several months. With more and more cold air up north, it pushes the jetstream further south, but this takes time, so Dec 21 is not usually the coldest day of the year.
2006-12-21 11:58:49 · answer #3 · answered by D C 2 · 0⤊ 0⤋
Even though the days are getting longer, the Northern Hemisphere is still tilted away from the Sun. It isn't until after the Spring Equinox that the Northen Hemisphere will begin being tilted towards the Sun.
If you were closer to the Equator, you would notice a change in temperature, but in areas further from the Equator, it isn't until after the Equinoxes that temperatures begin to change dramatically.
The Earth isn't at a 90 degree angle on its axis. It is tilted just over 23 degrees off it's vertical (north-south) axis. This is why it is winter in the Northern Hemisphere while it is summer in the Southern Hemisphere.
2006-12-21 11:44:28 · answer #4 · answered by T S 3 · 1⤊ 0⤋
The Northern Hemisphere is still losing heat.
You are incorrect in assuming that temperatures and day length are related. They are, but not directly. What really leads to falling temperatures is an imbalance in radiation where the earth loses more than it gains. There is still some summertime heat to be lost and it gets balanced off only in late January.
Similarly in the summer, the earth continues to gain more heat than it loses well after the summer solstice, into late July. That's why August is usually hotter than June despite shorter days
2006-12-21 17:44:44 · answer #5 · answered by Anonymous · 1⤊ 0⤋
because the eath is not angled straight up an down on it's axis, take an apple and put a pen through it, now turn it so that it is slightly tilted. keep that angle fixed (i think it is like 13 degrees) and move the apple around a basket ball. you see when it is winter in the norther hemisphere the northern part of the earth is farther away from the sun than the southern hemisphere. Also, as the eath rotates there is less time that the northern part is in the suns rays.
2006-12-21 11:38:43 · answer #6 · answered by bunja2 3 · 1⤊ 0⤋
Thermal lag. It works the same way in the summer... the real heat comes in August.
2006-12-21 14:02:34 · answer #7 · answered by Yak Rider 7 · 1⤊ 0⤋