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Wednesday marks the day when Ottawa has gained a full hour of daylight since winter began.
At the start of winter we were getting eight hours, 42 minutes of daylight. Wednesday brings nine hours and 43 minutes. And we are gaining more than two and a half minutes a day.
It’s higher in the sky, too, rising 27 degrees above the horizon at noon compared to 21 degrees in December. Overall we are getting as much sunshine at this time of years as we had back on Nov. 10.
On the first day of winter, the sun was about 23.5 degrees south of the equator (where 0 degrees is the equator and 90 degrees is the south pole.)
As February begins it crosses through 17 degrees south latitude. That means the sun appears directly overhead for people in central Brazil instead of southern Brazil. It is a northward shift of about 6.5 degrees, or 720 kilometres.
By the first day of spring it will reach the equator, in Ecuador, with 12 hours of daylight. That’s the time when we are gaining daylight the fastest — more than three minutes a day.
It has taken since Dec. 21 to gain this first hour of daylight because the change begins very slowly in December, but we will gain another hour in only three more weeks — by Feb. 21.
tspears@postmedia.com
twitter.com/TomSpears1
查看原文...
At the start of winter we were getting eight hours, 42 minutes of daylight. Wednesday brings nine hours and 43 minutes. And we are gaining more than two and a half minutes a day.
It’s higher in the sky, too, rising 27 degrees above the horizon at noon compared to 21 degrees in December. Overall we are getting as much sunshine at this time of years as we had back on Nov. 10.
On the first day of winter, the sun was about 23.5 degrees south of the equator (where 0 degrees is the equator and 90 degrees is the south pole.)
As February begins it crosses through 17 degrees south latitude. That means the sun appears directly overhead for people in central Brazil instead of southern Brazil. It is a northward shift of about 6.5 degrees, or 720 kilometres.
By the first day of spring it will reach the equator, in Ecuador, with 12 hours of daylight. That’s the time when we are gaining daylight the fastest — more than three minutes a day.
It has taken since Dec. 21 to gain this first hour of daylight because the change begins very slowly in December, but we will gain another hour in only three more weeks — by Feb. 21.
tspears@postmedia.com
twitter.com/TomSpears1
查看原文...
