European ceilometer and lidar networks for aerosol profiling and aviation safety the German contribution

Transcription

1 European ceilometer and lidar networks for aerosol profiling and aviation safety the German contribution Werner Thomas Deutscher Wetterdienst (DWD) Hohenpeissenberg Meteorological Observatory

2 A global inventory of lidars and ceilometers ~2260 Lidars und Ceilometer world wide (as of October 2017) 2085 Ceilometer, ~ 79% Vaisala (CT25K, CL31, some CL51), Lufft CHM15K, Eliasson CBME Lidars (AD-net, CIS-LInet, EARLINET, LALINET, MPLnet, NDACC, NOAA-CREST, POLLYnet, SPALINET, at NHMSs, some independent ) ~320 instruments offer quick looks (QL), ~125 instruments are linked to web pages WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 2

3 International efforts Harmonization of ceilometers and lidars in Europe through E-PROFILE ( until the end of 2018 Standardized products/data formats of various ceilometer types Exchange of data products within the met. service community BUFR format Quality assurance and monitoring of operations (24/7 service) More harmonization through TO-PROF COST ES1303, ( Standardized aerosol retrievals (supported by EARLINET) Quantitative results, i.e. attenuated backscatter (coefficients) Calculation of the error budget Preliminary attempts of data assimilation Ceilinex 2015: Ceilometer intercomparison campaign see results and data under WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 3

4 Germany s contribution WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 4

5 Instruments at DWD s network ~ 116 Jenoptik/Lufft Nimbus CHM15K, more devices planned until end nm, Nd:YAG laser; 8 µj, 15s intervals mean distance between instruments ~ 40 km clouds up to 15 km above ground, sensitive to aerosols in the troposphere Klett algorithm instruments are calibrated using the Rayleigh method (Wiegner and Geiß, 2012) coming soon (November 2017): 10 ceilometers with a depolarization channel all instruments are on-line, quick looks of attenuated backscatter available here WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 5

6 Operational Monitoring Routine checks running permanently, e.g. for available raw data, window contamination, correct data format, laser health checks a.s.o. WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 6

7 Simple deliverables of a ceilometer 24/7 service, autonomous operations Height above ground and geometrical thickness of cloud and aerosol layers The PBL- height, fog, precipitation, but this needs retrieval More information about aerosol, yes, in principle even more retrieval WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 7

8 Applications at DWD Replacement of eye observations at synop stations cloudiness Runway control at airports cloudiness, fog Volcanic ash aerosols Saharan dust energy meteorology DWD s Swiss Army Knife Future applications Weather forecast and data assimilation PBL- height, aerosols Global Atmosphere Watch (GAW): 4D- aerosol distribution aerosols first available product: 4- years climatology of Saharan dust events over Germany WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 8

9 Aerosol recognition by DWD Sahara dust plumes Happens frequently, ~ times per year in Southern Germany Sahara dust Biomass Burning plumes Happens few days per year but really strong events in 2013, 2016, 2017 Sea salt Rarely, mostly at coastal stations Biomass burning Volcanic Ash Fortunately hardly the case, two events in 2010 and 2011 Anthropogenic aerosol burden in the PBL WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 9

10 DWD ceilometer network - example CAMS forecast for October 17th, 9:00 UTC A mixture of Saharan dust and biomass burning plumes from wildfires in Northern Portugal and Spain We use the ceilometers to validate CAMS WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 10

11 From backscatter to mass concentration Backscatter coefficient Direct conversion by using in-situ measurements at mountain stations or from aircrafts Extinction Volume coefficient conc.???? Mass conc. Lidar ratio From literature Climatological value Value for actual aerosol type From actual AOD measurements Ext-to-volume ratio From literature Climatological value Value for actual aerosol type From actual AERONET inversion Particle density From literature Climatological value Value for actual aerosol type Lidar Multi-λ measurements: + Backscatter profiles + Extinction profiles / optical depth + (Depolarization) Komplex inversion algorithms POLYPHON (Ansmann et al. 2012) GARRLiC (Lopatin et al. 2013) Müller et al 2013, Böckmann and Osterloh 2014 Mass conc. with lower error margins WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 11

12 From backscatter to VAAC- mask Quick looks attn. backsc. calibrated not cloudscreened Mass conc. can be compared with aircraft and model data Particle backsc. 1 h average cloudscreened VAAC mask provided to forecasters and crisis team via Intranet WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 12

13 Conclusion and Outlook A combined Ceilometer- and Lidar network provides a 4-D representation of the aerosol distribution Detection and tracking of aerosol layers in time and space Enables, e.g. model validation COPERNICUS Atmospheric Monitoring Service dust plume tracking/analysis volcanic ash plume tracking/analysis calculation of mass concentrations under certain assumptions Ceilometers Stay tuned Must be calibrated for aerosol retrievals Must be harmonized, at least in the EU, w.r.t. data and algorithms Must allow access to instrumental raw data for aerosol retrievals ( message for the manufacturers!) Quantitative aerosol properties from a European combined Lidar-Ceilometer network will become available to the public within next years WMO Aeronautical Meteorology Scientific Conference 2017 Toulouse, France page 13

14 Thank you