General weather situation
Under weather situations ( GWL ) is understood to weather conditions over a wide area that does not change significantly during a several-day period.
Basics
A general weather situation is a certain atmospheric condition, the characteristic flow arrangement of which remains essentially the same for several days (definition according to Baur ). In general, three days are used as the assessment period.
The weather itself can change during a general weather situation, the character of the respective regional weather is retained. The regional formation and the typical sequence of large-scale weather patterns essentially shape the climate of an area. The general weather situation is of great importance for predicting the development of the weather and the weather for a longer period of time.
General weather conditions in Europe
A number of different large-scale weather situations can be distinguished for Europe, and there are different systems.
Low pressure hiking trails to Bebber
Wilhelm Jacob van Bebber developed a basic scheme of typical train routes of barometric minima ( low pressure trajectories) as early as the 1890s , which he divided into five groups:
- I: from the Atlantic north-east across the northern British Isles to north Scandinavia (Ia), and from there south-east (Ib), east (Ic), or north-east (Id)
- II: from the North Atlantic eastwards via central and southern Scandinavia to northeastern Europe
- III: from the North Atlantic south-east via southern Scandinavia to central-eastern Europe
- IV: from the mid-Atlantic north-east over the southern British Isles and southern Scandinavia (IVa) or north-central Europe (IVb) to north-eastern Europe
- V: from the mid-Atlantic south-east over Biscay into the Mediterranean area (Va), and from there north-east (Vb), east (Vc), or south-east (Vd)
From this simple model, which, however, did not define any concrete weather conditions in the course of the individual railways, the designation Vb-Wetterlage has been preserved, the main phase of the north-east trajectory from a Mediterranean low over the Adriatic and Danube region to the Baltic States, the heavy rainfall caused by sliding from the south-east onto the Alps and Carpathian leads.
Large weather typology according to Hess / Brezowsky
In addition to computer-aided processes, the German Weather Service also classifies large-scale weather situations according to Paul Hess and Helmuth Brezowsky - in particular according to the flow situation ( cyclonic or anticyclonal ) and the location of the action centers in the earth's atmosphere and the frontal zone .
- Forms of circulation
- Zonal form of circulation: follows a smooth west-east flow between a deep -reaching subtropical high pressure area in the normal position above the North Atlantic and a deep -reaching low pressure area in the subpolar space - typical examples: western locations
- Mixed form of circulation: The anticyclonic control centers are shifted northwards to about 50 ° latitude compared to the western locations - Examples: Southwest locations (control center Eastern Europe), Northwest locations (control center East Atlantic), High Central Europe (as the center), including low Central Europe
- meridional circulation Form: Stationary, blocking high pressure areas between 50 ° and 65 ° of latitude - Typically: Northern layers, south-facing, easterly and trough layers with a north-south axis direction, northeast and southeast layers
- General weather conditions
No. | Abbr. | E.g. | |
---|---|---|---|
A) General weather conditions of the zonal form of circulation | |||
1 | West exposure, anticyclonal | WA | |
2 | West facing, cyclonic | WZ | |
3 | South west facing | WS | |
4th | Angular west facing | WW | |
B) General weather conditions of the mixed form of circulation | |||
5 | Southwest exposure, anticyclonal | SWA | |
6th | Southwest exposure, cyclonic | SWZ | |
7th | Northwest exposure, anticyclonal | NWA | |
8th | Northwest facing, cyclonic | NWZ | |
9 | High Central Europe | HM | |
10 | High pressure bridge (back) Central Europe | BM | |
11 | Deep Central Europe | TM | |
C) General weather conditions of the meridional form of circulation | |||
12 | North facing, anticyclonal | N / A | |
13 | North facing, cyclonic | NZ | |
15th | High Northern Sea - Iceland , anticyclonal | HNA | |
15th | High Northern Sea Iceland, cyclonic | HNZ | |
16 | High British Isles | HB | |
17th | Trough Central Europe | TRM | |
18th | Northeast exposure, anticyclonal | NEA | |
19th | Northeast, cyclonic | NEZ | |
20th | High Fennoscandia , anticyclonal | HFA | |
21st | High Fennoscandia, cyclonic | HFZ | |
22nd | High Northern Fennoscandia, anticyclonal | HNFA | |
23 | High Northern Fennoscandia, cyclonic | HNFZ | |
24 | Southeast exposure, anticyclonal | SEA | |
25th | Southeast exposure, cyclonic | SEZ | |
26th | South facing, anticyclonal | SA | |
27 | South facing, cyclonic | SZ | |
28 | Deep British Isles | TB | |
29 | Trough Western Europe | TRW | |
crossing | U |
Objective weather situation classification for Germany (DWD)
The German Weather Service has developed a model based on three measurement criteria that includes 40 weather situations for Germany and the surrounding area. Large-scale direction of flow (5 values: undefined, northeast, southeast, southwest, northwest), cyclonality or anticyclonality of the ground-level and mid-tropospheric currents (1000/550 hPa; 4 values) as well as the moisture content of the atmosphere (2 values: dry, moist ) combined. An example is then:
- Class no. 4: Direction of flow southwest, flow A / A, dry → short code SWAAT
All combinations were classified, including those that occur extremely rarely (only a few times per decade). The five most common weather patterns (1979–1990) are:
Class no. | Short identifier | Frequency (in%) | |
---|---|---|---|
1 | 1 | XXAAT | 9.4 |
2 | 15th | NWAZT | 8.8 |
3 | 9 | SWAAF | 8.7 |
4th | 5 | NWAAT | 8.3 |
5 | 10 | NWAAF | 7.5 |
Austrian Weather Pattern Scheme (ZAMG)
Since Austrian meteorology has to take into account not only the Atlantic climate but also the Pannonian and Mediterranean climates with the subtype of the Illyrian climate , as well as action centers from the Sahara to the Black Sea region (which are not taken into account according to Hess / Brezowsky), the Central Institute for Meteorology uses and geodynamics in Vienna the following scheme:
weather condition | Abbr. | E.g. |
---|---|---|
High above Western and Central Europe | H | |
Intermediate high | H | |
Zonal high pressure bridge | Hz | |
High with core above Fennoscandia | HF | |
High with core above Eastern Europe | HE | |
North facing | N | |
Northwest facing | NW | |
West facing | W. | |
Southwest facing | SW | |
South facing | S. | |
Gradient weak location | G | |
Deep south of the Alps | TS | |
Deep above the western Mediterranean | TwM | |
Deep in the southwest of Europe | TSW | |
Deep in the British Isles | TB | |
Meridional low pressure channel | TR | |
Continental low | Tk | |
Deep on the Adriatic - Poland train route | Vb |
literature
- F.-W. Barley sheaf , PC Werner, U. Rügen (collaborators) : Catalog of the major weather conditions in Europe (1881–1998). After Paul Hess and Helmuth Brezowsky . 5th edition. Potsdam / Offenbach a. M. 1999 ( dwd.de [PDF; 3.9 MB ]).
Web links
- General weather situation: annual and monthly overviews, German Weather Service DWD, since 2007
- Monthly overview: weather conditions. Central Institute for Meteorology and Geodynamics ZAMG (query, since 1999, with legend)
- COST 733 - Harmonization and Applications of Weather Type Classifications for European regions . On the website geo.uni-augsburg.de
proof
- ↑ The general weather conditions in Europe - characterization and hazard potential. unwetter.de, accessed on December 3, 2008 .
- ↑ a b Examples: Analyzes. DWD, on the website of the Institute for Meteorology, FU Berlin (met.fu-berlin.de).
- ↑ a b Analysis 20030112
- ↑ a b Analysis 20030101
- ↑ a b Analysis 20030228
- ↑ a b Analysis 20030426
- ↑ a b Analysis 20030706
- ↑ a b Analysis 20030501
- ↑ a b Analysis 20030527
- ↑ a b Analysis 20030722
- ↑ a b Analysis 20030410
- ↑ a b Analysis 20030824
- ↑ a b Analysis 20030421
- ↑ a b Analysis 20030105
- ↑ a b Analysis 20031229
- ↑ a b Analysis 20030214
- ↑ a b Analysis 20051015
- ↑ a b Analysis 20031013
- ↑ Analysis 20050819
- ↑ a b Analysis 20030412
- ↑ a b Analysis 20030819
- ↑ a b Analysis 20030222
- ↑ a b c Analysis 20030121
-
↑ The objective weather situation classification; and description of the procedure and the weather condition classes;
Ernst Dittmann u. a. (S. Barth, G. Müller-Westermeier, J. Lang): Objective weather situation classification. Series of reports from the German Weather Service 197, Offenbach am Main 1995 (pdf);
Objective weather situation classification. (In: Wettwetterlexikon. )
All: Deutscher Wetterdienst, dwd.de (accessed May 30, 2016). - ↑ Classification area. dwd.de
- ↑ Dittmann et al. a .: Objective weather situation classification. 1991, Table 2: Numbering, definition and short code of the weather situation classes, p. 27; The same. Key figures and identifiers of the 40 objective weather situations , dwd.de.
- ↑ Dittmann 1991, p. 7.
- ↑ Dittmann 1991, 5.1 Weather Calendar, p. 17 ff, especially p. 19.
- ↑ Analysis 20030901
- ↑ Analysis 20030711
- ↑ Analysis 20031015
- ↑ Analysis 20031022
- ↑ Analysis 20031002
- ↑ Analysis 20031020
- ↑ Analysis 20030731
- ↑ Analysis 20030215
- ↑ Analysis 20050822 ( Alpine floods 2005 )
- ↑ Project (ex cost733.org) finished, see cost733.met.no ; accessed May 30, 2016; Final reports on ESSEM COST Action 733 , European Cooperation in Science and Technology, cost.eu.