Wednesday, January 4, 2017

When Will Spring Planting Season Arrive?



If you're a star watcher, you could have breathed a sigh of relief on December 25th when the days started getting longer for the third day in a row. Three of a thing is a pattern and that means we can expect longer days and warmer weather. That's how primitive man may have reckoned, anyway; of course, we modern people know better. Because of the 23.5 degree tilt of the Earth's axis, the northern hemisphere receives the Sun's rays more directly as we approach the summer solstice. That means more energy from the Sun is pouring into the northern hemisphere. Additionally, the northern hemisphere has a larger land mass than the southern hemisphere, and land warms up more quickly than water. So even though the Earth is further away from the Sun in the summer (due to its elliptical orbit) the land heavy northern hemisphere heats up more quickly and as a result, the Earth as a whole is more than 4 degrees warmer in the summer than in the winter.

But when the Sun starts returning to the northern hemisphere, why does it take several months before the atmosphere starts warming up, and why does it stay warmer longer, i.e. even after we've passed the summer solstice? The answer is that the rise and fall of temperature depends on the difference between the absorption of heat energy from the Sun's rays minus the loss of radiant energy from the Earth's atmosphere. This is called the Earth's energy budget. After the winter solstice, the northern hemisphere starts receiving the Sun's rays more directly. As we approach the summer solstice, the northern hemisphere receives more and more heat energy until it reaches a point in time (in late winter) when the incoming energy is greater than the outgoing energy. On this date, temperatures began increasing; the equilibrium date is different for each latitude (sooner for southern locations). Even after the summer solstice (the day of the earth's greatest tilt towards the Sun), the northern hemisphere continues to receive more heat energy during the day then is lost at night. Temperatures continue to remain hot until late in the summer when the energy budget of the northern hemisphere drops into the red.

For the best in spring landscaping and masonry in the Yorktown Heights area contact the Turf Barbers