Why So Hot
All my crew is complaining about the heat. Why is it so hot? Maybe it just seems hot because the last 2 summers have been relatively cool. Actually we have not even touched 90 degrees yet this July...........albeit that will probably change today.
What is the catalyst is for such extremely hot temperatures? One reason I've heard is the location of the Earth in relation to the Sun. After all this is summer, and we are probably closest to the Sun, right?
Wrong. It’s actually quite the opposite. On Tuesday, July 6, 2010, the Earth was at aphelion, its farthest point from the Sun for this year.
Conversely, back on January 2, we were physically closest to the Sun, at perihelion. The difference between the closest and farthest points is equal to 3,105,866 miles, which sounds like a lot, but amounts to an overall change of just over 3%.
In fact, this relatively small difference in the Earth’s distance from the Sun has very little effect on what astronomers refer to as our “insolation,” (the amount of sunlight we receive per unit of surface area).
The reason for the temperature difference lies in the tilt of the axis of the Earth itself, not the proximity of the Sun. In the summer, the Northern Hemisphere is tipped toward the Sun so that its light falls more directly and is more concentrated on each unit of the surface. This, along with the fact that the Sun shines for a longer time each day, makes summer a warmer season than winter.
Saturday, July 3rd, also marked the beginning of the “Dog Days of Summer,” which also closely coincided with the start of the searing heat for the Eastern U.S. Perhaps this has something to do with the recent siege of hot weather?
Everyone talks about “dog days” but few know what the expression means. Some say that it signifies hot sultry days “not fit for a dog.” Others say it’s the weather in which dogs go mad. But the dog days are defined as the period from July 3 through August 11 when the Dog Star, Sirius, rises about the same time as the sun.
As a result, some people felt that the combination of the brightest luminary of the day (the Sun) and the brightest star of night (Sirius) was responsible for the extreme heat that is experienced during the middle of summer.
Sirius, being so near to the Sun in our current sky, is invisible now, but beginning around August 11, just before sunrise, it might again be glimpsed rising just above the southeast horizon.
In ancient Egypt, the new year began in August with the return of Sirius. Its annual reappearance was a warning to people who lived along the Nile River. The star always returned just before the river rose, and so announced the coming of floodwater. People then opened the gates of canals that irrigated their fields.
We know today, of course, that Sirius has nothing to do with hot temperatures or floods, but after all of these years the term “Dog Days” just stuck!
Sooooooooooo..... yea it is hot, but it is summer and that is what it should be.......hot..
Despite the heat, us snow lovers are already wondering what this winter will bring. Indications are that El Nino is fast fading and some form of La Nina or Neutral winter will take its place. The closest duplication of the current pattern was last seen prior to the winter of 92-93. That winter gave us an unprecedented 86 days of skiing. That sounds pretty good to me!
Enjoy the summer!
What is the catalyst is for such extremely hot temperatures? One reason I've heard is the location of the Earth in relation to the Sun. After all this is summer, and we are probably closest to the Sun, right?
Wrong. It’s actually quite the opposite. On Tuesday, July 6, 2010, the Earth was at aphelion, its farthest point from the Sun for this year.
Conversely, back on January 2, we were physically closest to the Sun, at perihelion. The difference between the closest and farthest points is equal to 3,105,866 miles, which sounds like a lot, but amounts to an overall change of just over 3%.
In fact, this relatively small difference in the Earth’s distance from the Sun has very little effect on what astronomers refer to as our “insolation,” (the amount of sunlight we receive per unit of surface area).
The reason for the temperature difference lies in the tilt of the axis of the Earth itself, not the proximity of the Sun. In the summer, the Northern Hemisphere is tipped toward the Sun so that its light falls more directly and is more concentrated on each unit of the surface. This, along with the fact that the Sun shines for a longer time each day, makes summer a warmer season than winter.
Saturday, July 3rd, also marked the beginning of the “Dog Days of Summer,” which also closely coincided with the start of the searing heat for the Eastern U.S. Perhaps this has something to do with the recent siege of hot weather?
Everyone talks about “dog days” but few know what the expression means. Some say that it signifies hot sultry days “not fit for a dog.” Others say it’s the weather in which dogs go mad. But the dog days are defined as the period from July 3 through August 11 when the Dog Star, Sirius, rises about the same time as the sun.
As a result, some people felt that the combination of the brightest luminary of the day (the Sun) and the brightest star of night (Sirius) was responsible for the extreme heat that is experienced during the middle of summer.
Sirius, being so near to the Sun in our current sky, is invisible now, but beginning around August 11, just before sunrise, it might again be glimpsed rising just above the southeast horizon.
In ancient Egypt, the new year began in August with the return of Sirius. Its annual reappearance was a warning to people who lived along the Nile River. The star always returned just before the river rose, and so announced the coming of floodwater. People then opened the gates of canals that irrigated their fields.
We know today, of course, that Sirius has nothing to do with hot temperatures or floods, but after all of these years the term “Dog Days” just stuck!
Sooooooooooo..... yea it is hot, but it is summer and that is what it should be.......hot..
Despite the heat, us snow lovers are already wondering what this winter will bring. Indications are that El Nino is fast fading and some form of La Nina or Neutral winter will take its place. The closest duplication of the current pattern was last seen prior to the winter of 92-93. That winter gave us an unprecedented 86 days of skiing. That sounds pretty good to me!
Enjoy the summer!
posted by Snowstar Ski Resort at
7:47 AM
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