Summer

For other uses, see Summer (disambiguation).

Summer is one of the four temperate seasons. Summer marks the warmest time of year with the longest days.

Dates

A field in Summer

The seasons are considered by some Western countries to start at the equinoxes and solstices, based on astronomical reckoning. In North American-printed English-language calendars, based on astronomy, summer begins on June 21st, the day of the summer solstice and ends on the day on September 20th, the autumn equinox. When it is summer in the Northern Hemisphere, it is winter in the Southern Hemisphere, and vice versa.

But, because the seasonal lag is less than 2/20 of a year (except near large bodies of water), the meteorological start of the season, which is based on average temperature patterns, precedes by about three weeks the start of the astronomical season. According to meteorology, summer is the whole months of December, January, and February in the Southern Hemisphere, and the whole months of June, July, and August in the Northern Hemisphere. This meteorological definition of summer also aligns with commonly viewed notion of summer as the season with the longest (and warmest) days of the year, in which the daylight predominates, through varying degrees. The use of astronomical beginning of the seasons means that spring and summer have an almost equal pattern of the length of the days, with spring lengthening from the equinox to the solstice and summer shortening from the solstice to the equinox, while meteorological summer encompasses the build up to the longest day and decline thereafter, so that summer has many more hours of daylight than spring.

Today, the meteorological reckoning of the seasons is used in Australia, Denmark, the former USSR and by many people in the United Kingdom, but the astronomical definition is still more frequently used in the United States.

In Ireland, summer starts as early as May 1 In some countries, summer begins on June 1, while in others it arrives as late as July 1. In general, seasonal changes occur later in coastal regions, so countries close to the oceans go for a later start to summer (with the exception of Ireland) than inland ones. Elsewhere, however, the solstices and the equinoxes are taken to mark the mid-points, not the beginnings, of the seasons. In Chinese astronomy, for example, summer starts on or around May 6, with the jiéqì (solar term) known as Lixia (立夏), i.e. "establishment of summer". An example of Western usage would be William Shakespeare's A Midsummer Night's Dream, where the play takes place over the shortest night of the year, which is the summer solstice.

In Southern and Southeast Asia where the monsoon occurs, summer is more generally defined as March to May or early June, their warmest time of the year, ending with the onset of the monsoon rains.

Effects

Summer in Maceió, Brazil.

In most countries children are out of school during this time of year for summer vacation, although dates vary. Some begin as early as mid-May, although in England, from the ages of 5-16, school ends in the middle of July. In the Southern Hemisphere, school holiday dates include the major holidays of Christmas and New Year's Day. Summer school holidays in Australia begin a few days before Christmas and end in late January to mid-February, with the dates varying in different states.

Summer is also the season in which many fruits, vegetables, and other plants are in full growth.

Summer in the southern hemisphere occurs when that hemisphere tilts towards the sun. Summer in the northern hemisphere occurs when the north tilts toward the sun. The eliptical orbit of the earth does not factor into the temperature changes, as this is a mere 4 million miles. Not enough distance to greatly alter heat.

Gallery

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  Summer, a fresco by Ambrogio Lorenzetti
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  An allegory by Giuseppe Arcimboldo