Meteorological observations of signal stations - a data source for the analysis of extreme weather events? Dörte Wagner (*), Birger Tinz (Deutscher Wetterdienst, CLISAP, Hamburg) and Hans von Storch, HZG, Uni Hamburg, CLISAP, Germany) (*) nee Röhrbein 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Data archive of signal stations Cases studies storm surges 1906/1913 Outlook: Long term evaluation of SLP, wind speed and direction 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Signal Stations - Overview Submit storm warnings of German Marine Observatory Hamburg to shipping and coastal population via optical signals Warnings sent by telegram to post office next by signal station  signal station (nearly in real time!) Signalstationen Helgoland. Sturmwarnung vom 01. Januar 1930 10:45 Uhr: Tief 735 südlich Island dringt ostwärts vor. Gefahr starken steifen bögen SW bis W-Windes. Signalball. Warnung empfangen um 10:50 Uhr, Signal aufgesetzt um 11:00 Uhr. Signal Station Heligoland: Warning of 01th January 1930: 1) Issued by Marine Obs. 10:45 am, 2) Received at signal station Heligoland 10:50 am, 3) signal set 11:00 am 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Signal stations - Overview Flags, cone and bin at the signal mast stand for wind force, wind direction and change of direction Data collected for verifying storm warnings of the German Marine Observatory Hamburg Normal recording times 8, 14 and 21 CET When storm warning were issued, more frequent observations were recorded. Written records were sent to German Marine Observatory Hamburg at the end of each month. Thus, data have not been used for the synoptic analysis and weather forecasting Data are independent of the regular weather data for the long period1877-1999 Signal stations - Overview Sturmwarnung hinzufügen (1913) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Signal Stations - Positions About 160 Signal Stations German Bight and southern Baltic Sea coast Europe NORTH SEA http://www.dwd.de/EN/ourservices/signal_stations/signalstationen.html 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Handwritten Journals About 800 handwritten journals are archived at the German Meteorological Service in Hamburg Cover a period of 123 years (1877 -1999) Data were not recognized for years Data are digitized by DWD since 2010 (30 % ready) Data will be made available 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Distribution of numbers of stations (asterisks) and digitized data (bars) for 1875 to 1999. 25 person years are needed for complete digitization 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Weather diary of a signal station Dornbusch (Germany) 01./02.01.1910 Element Unit Time window Air pressure mmHg 1877-1939 Wind direction Wind rose with 8/16/32 directions 1877-1999 Wind force Beaufort, kt weather Key 0…9 Waves Key 0 … 9 1877-1938 sight 1938-1999 precipitation mm Comments Significant Weather, broken dykes, marine desaster, ... Recorded weather elements at signal stations. 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Why could these data be valuable for scientific research? Data of the signal stations expand the monitoring network at the German Bight and Baltic Sea coast in time and space Detailed study of historical extreme events in space and time Determination of low frequency variability and trends Are the data homogeneous in space and time? 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Case study: Storm surge at the southwestern coast of the Baltic Sea 30 2nd highest recorded water level in the region of Zingst Significant damage of infrastructure destroyed railway bridge in the coastal region (source: old postcard, archive DWD) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Wind force and direction of 7 regular weather station of the German Marine Observatory at 30.12.1913 20 CET (Deutsche Seewarte/Kaiserliche Marine 1913) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Wind force and direction of 7 regular weather station of the German Marine Observatory at 30.12.1913 20 CET+ additional observations at 73 signal stations (from Röhrbein und Güttner 2015) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Seewarte (1913) and reconstruction using signal station SLP data (Weather report of the Deutsche Isobars of Deutsche Seewarte (1913, thick) Seewarte (1913) and reconstruction using signal station SLP data (thin lines, from Wagner et al. 2016) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Chronological sequences of water level data (BSH, Wasserstandsdienst Rostock ), wind force and direction at signal station Greifswalder Oie in the period from 27th December 1913 to 3nd January 1914 (from Röhrbein and Güttner 2015). 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Storm surge in the German Bight, 12. March 1906 Wind force and direction as well as SLP at 12. March 1906 08 CET, (from Röhrbein and Güttner 2015). 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Distribution of air pressure and wind force at station Borkum Distribution of air pressure and wind force at station Borkum. Circles display routine observations and dots the additional observations during storm warning (from Wagner et al. 2016) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Outlook: Long term evaluation of SLP, wind speed and direction 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Long term evaluation of Wind direction in ° Wind direction (08, 14 and 21 CET) at Signal Station Schleimünde 1877-1984. Observations are according to wind roses with 8, 16 or 32 directions 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Long term evaluation of Wind speed in m/s Yearly means of wind speed at Signal Station Travemünde 1877-1999. 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Long term evaluation of Wind SLP in hPa Yearly means of SLP at Signal Stations Emden, Norderney and spatial mean of the three stations1912-1939. 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Conclusion 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Literature Deutsche Seewarte/Kaiserliche Marine 1913: Täglicher Wetterbericht. (http://docs.lib.noaa.gov/rescue/data_rescue_germany.html) Kaspar, F., Tinz, B., Mächel, H., Gates, L. 2015: Data rescue of national and international meteorological observations at Deutscher Wetterdienst. Adv. Sci. Res. 12, 57-61, doi:10.5194/asr-12-57-2015 (http://www.adv-sci-res.net/12/57/2015/) Röhrbein, D., Güttner, S. 2015: Investigation on the 1913 New Year‘s Eve. Der Wetterlotse / Maritime Meteo News, DWD-Eigenverlag, 02/2015, 17 - 22 (https://www.dwd.de/EN/ourservices/wetterlotse/wetterlotse.html) Wagner, D., Tinz, B., von Storch, H. 2016: Newly Digitized Historical Climate Data of the German Bight and the Southern Baltic Sea Coasts. Journal of Atmospheric and Oceanic Technology, in review. More Information: http://www.dwd.de/EN/ourservices/signal_stations/signalstationen.html 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de

Archiv DWD Hamburg 800 Bücher mit handschriftlichen Originalaufzeichnungen der Wetterbeobachtungen von Signalstationen Bücher mit den handschriftlichen Originalaufzeichnungen der Wetterbeob-achtungen an den Signalstationen (ca. 800 Bücher, 35 lfm, Foto: B. Tinz) 1st Baltic Earth Conference, Nida, Lithuania, 13 to 17 June 2016 Signal Stations, birger.tinz@dwd.de