Chunfen

The beginning of spring or beginning of spring, so the beginning of the season spring, can either astronomical, meteorological or phenological be determined (after the development of the plants).

Northern Hemisphere

Astronomical spring in the northern hemisphere by the primary equinox (primary day and night are equally long ) is set. The calendrical occurrence time varies and falls depending on, among other things, the distance from the last leap year, on the 19th, 20th or 21st of March.

At the beginning of the 20th century, the beginning of spring was always on March 21, 1920 for the first time in leap years on March 20, 1952, two years in a row on 20 and 21 March, from 1988 on 20 March and only all four years on 21 March, for the first time in 1991 and most recently 2011. Starting in 2048 for the first time held in leap years on March 19, the beginning of spring. This applies only to the CET. For details, see → season.

Meteorological beginning of spring is located on the northern hemisphere of the earth early in the month, on March 1. The meteorological beginning of spring by the World Meteorological Organization (World Meteorological Organization, WMO), a United Nations agency established. So three months are assigned to the seasons. December, January and February are the winter months, the spring comprises - meteorologically seen - the months of March, April and May. In this way, statistics ( such as monthly mean values ​​) and climate comparisons are easily created and compared.

• April 22-April 28
• April 29 - May 05
• May 06 - May 12
• May 13 to May 19
• May 20 to May 26

Phenological the Spring in Central Europe is divided into three phases:

• Early Spring: until the Salweidenkätzchen are yellow pollen from the flowering of snowdrops and hazel.
• Erstfrühling: From the beginning of flowering of forsythia and foliation of gooseberry until the beginning of flowering pear trees.
• Full Spring: From the beginning of flowering of apple trees and lilacs to the flowering of the rowan and the Meadow Foxtail.

The beginning of spring phenological changes not only according to the longitude and latitude but also on the level, after the major climate zones and small-scale, depending on climatic conditions. So start each spring phases in sheltered areas of cities often much earlier than in the open field.

The spring moves in the mountains slowly up the slopes, being earlier than on the northern slopes to the southern slopes.

The full spring begins in Europe in the southwest of Portugal in Faro late February and moves on to the northeast, where he reached around the 20th April with the Upper Rhine Valley Germany. Then he pulls the flat landing swiftly on to Finland, which he reached the end of May. It takes about 90 days for the distance of about 3,600 kilometers. So he pulls at a rate of an average of 40 kilometers a day through Europe. This is followed by migratory birds: The arrival occurs according to a clear timetable. Star and Laundry herald the early spring, swifts and nightingales return to the last days of April, and there are also early arrivals. Arrival of migratory birds in the south earlier back in Scandinavia they arrive later, also for the cuckoo this is occupied. The migratory birds are considered messengers of spring, because the bird sounds are heard again in nature.

The timing of phenological spring commencement From year to year changes, however, a tendency seems to emerge that spring starts in Europe before. Also various species of migratory birds return because of global warming a few days earlier than they did 30 years ago back.

For calculating the date of Easter March 21 is always used as the beginning of spring.

Southern Hemisphere

Astronomical spring in the southern hemisphere by the Sekundaräquinoktium ( secondary day and night are equally long ) is set. The calendrical occurrence time varies and falls depending on, among other things, the distance from the last leap year, on the 22nd or 23rd of September.