Journal cover Journal topic
Natural Hazards and Earth System Sciences An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 2.883 IF 2.883
  • IF 5-year value: 3.321 IF 5-year
    3.321
  • CiteScore value: 3.07 CiteScore
    3.07
  • SNIP value: 1.336 SNIP 1.336
  • IPP value: 2.80 IPP 2.80
  • SJR value: 1.024 SJR 1.024
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 81 Scimago H
    index 81
  • h5-index value: 43 h5-index 43
Discussion papers
https://doi.org/10.5194/nhess-2019-234
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-2019-234
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: research article 04 Sep 2019

Submitted as: research article | 04 Sep 2019

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Natural Hazards and Earth System Sciences (NHESS).

An 18-year climatology of derechos in Germany

Christoph P. Gatzen1, Andreas H. Fink2, David M. Schultz3, and Joaquim G. Pinto2 Christoph P. Gatzen et al.
  • 1Institut für Meteorologie, Freie Universität Berlin, Berlin, Germany
  • 2Institute of Meteorology and Climate Research – Department Troposphere Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
  • 3Center for Atmospheric Science, School of Earth and Environmental Sciences, University of Manchester, Manchester, United Kingdom

Abstract. Derechos are high-impact convective wind events that can cause fatalities and widespread losses. In this study, 40 derechos affecting Germany between 1997 and 2014 are analysed to estimate the derecho risk. Similar to the United States, Germany is affected by two derecho types. The first derecho type forms in south-westerly 500-hPa flow downstream of intense west-European troughs and accounts for 22 of the 40 derechos. These derechos are named warm-season type due to their peak occurrence in June and July. Warm-season type derechos frequently start over southwestern Germany in the afternoon and move either eastward along the Alpine forelands or north-eastward across southern central Germany. Only one warm-season derecho moved across the North Sea and one moved across the Baltic Sea in the 18-year period. Proximity soundings of German warm-season type derechos indicate strong deep-layer vertical wind shear with a median of 20 m s−1 0–6-km shear and mixed-layer Convective Available Potential Energy (mixed-layer CAPE) between 20 and 2600 J kg−1 with a median around 500 J kg−1. The second derecho type forms in north-westerly 500-hPa flow and accounts for 18 of the 40 derechos. These derechos form in strong north-westerly flow, frequently in association with mid-tropospheric PV intrusions. They are named cold-season type because they are associated with a secondary peak from December to February. Cold-season type derechos start over or close to the North Sea and primarily affect north and central Germany; their start time is not strongly related to the peak of diurnal heating. Proximity soundings indicate high-shear–low-CAPE environments with a median 0–6-km shear of 35 m s−1 and a median mixed-layer CAPE of 3 J kg−1. Environmental CAPE is zero in almost half of cold-season type proximity soundings. Fifteen warm-season type and nine cold-season type derechos had wind gusts reaching 33 m s−1 in at least at three locations. Although warm-season derechos are more frequent, the path length of cold-season type derechos is on average 1.4 times longer. Thus, these two types of German derechos are likely to have similar impacts.

Christoph P. Gatzen et al.
Interactive discussion
Status: open (extended)
Status: open (extended)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Christoph P. Gatzen et al.
Christoph P. Gatzen et al.
Viewed  
Total article views: 360 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
276 80 4 360 2 3
  • HTML: 276
  • PDF: 80
  • XML: 4
  • Total: 360
  • BibTeX: 2
  • EndNote: 3
Views and downloads (calculated since 04 Sep 2019)
Cumulative views and downloads (calculated since 04 Sep 2019)
Viewed (geographical distribution)  
Total article views: 228 (including HTML, PDF, and XML) Thereof 224 with geography defined and 4 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 16 Nov 2019
Publications Copernicus
Download
Citation