![]() ![]() Thus astronomical Autumn begins, continuing until the Winter Solstice, when daylight hours are at their shortest (around 21 December), and so on. So the Summer begins around the Summer Solstice, when daylight hours are at their longest (around 21 June), and ends around the Equinox, when days and nights are of equal length (around 21 September, on 22 September this year). “Looking at longer timescales, our recently updated 30-year averages can show us how ‘normal’ seasons are changing over time, giving us clues about trends in the UK’s climate.”Īstronomical definitions of seasons also exist – using the Earth’s position relative to the Sun as the cue for separating one season from another via equinoxes and solstices. It also has the advantage that each season is roughly the same length, neatly dividing the year into four quarters. Mike Kendon, of the Met Office National Climate Information Centre, said: “Defining seasons in this way means we can compare weather from one season or year to the next. Of course, this is fairly arbitrary, but provides a consistent basis for the Met Office, as the holder of the UK’s national weather and climate records, to calculate long term averages and provide seasonal climate summaries from year to year. So, Summer is June, July and August Autumn is September, October and November, and so on. In meteorological terms, it’s fairly simple – each season is a three month period. While those south of the equator will begin to enjoy longer days and warmer weather, people in the United States and other parts of the world will have to deal with increasingly shorter days and increasingly cold weather.Seasons are fundamental to how we understand the UK climate and the environment around us, but how do we define when they start and end? “The ‘nearly’ equal hours of day and night is due to refraction of sunlight or a bending of the light’s rays that causes the sun to appear above the horizon when the actual position of the sun is below the horizon,” it says. The National Weather Service notes that the equinoxes are the only two times of the year when the Earth’s axis is tilted neither toward nor away from the sun, resulting in a “nearly” equal amount of daylight and darkness at all latitudes. Thus, the length of daylight is equal to that of the night (neglecting twilight) and this day is termed the equinox from the Latin for ‘equal night.'”Īfter the equinox, there’s less and less daylight each day until the winter solstice in December–this year slated for December 21.Īfter the solstice days get longer until the spring equinox in March–next year on March 20. “These are the two days of the year when the Sun is above the horizon for exactly half the day and is below the horizon an equal amount of time. It is one of two times during the year when this happens, the other being on the first day of spring,” the nonprofit said. “What is the astronomical significance of this moment? At this moment the Sun in its apparent path around the sky will stand directly over the equator of the Earth. EDT, according to astronomers at the Pisgah Astronomical Research Institute. The first moment of autumn will be 10:29 p.m. Fall begins on Monday, September 22 when the Sun crosses the celestial equator in the sky heading south. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |