9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 1 German National Report on Ozone Research and Monitoring Ulf Köhler - DWD The 9th Meeting of the Ozone Research Managers of the Parties to the Vienna Convention Geneva, May 2014

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 2 German contribution to ozone research: Almost 20 institutes for Ozone - - Monitoring - Modelling - Research & Development - QA/QC

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 3 German Network for long-term observations of ozone, ozone related trace gases and UV incl. 2 calibration centres with a large variety of instruments Too many activities to present all, focus only on some higlights

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 4 Results of observations Ozone sondes Fig. 2: Time and altitude plot of ozone partial pressure from German ozone soundings over Antarctica. Plot by G. König-Langlo, AWI Bremerhaven. Fig.6: “Arctic 2011 Ozone hole profiles”: Ozone loss profile. Illustration of the vertical profile of the ozone hole at an altitude of around 15 and 25 kilometres. The red curve shows that the ozone loss profile in spring 2011 was largely comparable to the Antarctic ozone holes. Graphic: Markus Rex, Alfred Wegener Institute. AWI data from Antarctica: Slight improvement can be seen. Ozone holes in the past years have not been as deep as before 2000

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 5 Results of observations Ground based observations Fig. 10: Observed annual mean total ozone at Hohenpeissenberg, and multiple linear regression analysis of the magnitude of contributing factors. Top: Black: Observations at Hohenpeissenberg (47.8°N, 11°E). Gray: Multiple linear regression result. Red: Ozone variation attributed to Effective Equivalent Stratospheric Chlorine (EESC). Lower graphs: Ozone variation attributed to the QBO (magenta), to the Arctic Oscillation (AO, blue), to enhanced stratospheric aerosol (green), and to the 11-year solar cycle (orange). Plot by W. Steinbrecht, DWD. Hohenpeissenberg long-term record shows at least the end of the negative trend of TOC since the 90ties. Expected recovery cannot be finally confirmed yet. Extreme variability between 2010 – 2013: Very low values in 2011 and 2012 indicate the still existing capability for high ozone deficits

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 6 Fig. 12. Timeseries of annual mean ozone from the GOME/SCIAMACHY/GOME-2 dataset along with the SBUV MOD V8.6 merged ozone and World Ozone and UV Data Center (WOUDC) ground data. Annual means are shown for various latitude bands from NH middle latitudes (30°N-60°N), tropics (25°S-25°N), to SH middle latitudes (30°S-60°S) in the lower three panels. The global mean (60°S-60°N) is shown in the top panel. Indicated in the plots are the expected change in ozone from the effect of the equivalent effective stratospheric chlorine (EESC). Tropical ozone does not show a significant long-term trend with respect to EESC changes, but solar cycle (11 years) variability is evident. The EESC curves indicate a modest (anthropogenic) recovery of ozone of roughly 2-3 DU at middle latitudes in the last ten years. However, year-to-year changes can amount to up to ±15 DU (Plot by M. Weber, IUP Bremen). GOME/SCIAMACHY/GOME-2 datasetSBUV MOD V8.6WOUDC Results of observations Satellite data Analyses of the satellite data by the Bremen University (IUP) possibly reveals the beginning of a slight recovery of the ozone layer in the Northern Mid- latitudes, but the high variability and the potential for extremely low values can be seen too

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 7 Results of observations Fig. 9: Total stratosph. Bry from balloon-borne BrO observations (squares) and annual means from ground-based measurements at Harestua (60°N) and Lauder (45°S). The stratospheric data are compared to bromine (ppt) measured at the Earth’s surface, with varying amounts of very short lived Bromine species added (blue lines). By K. Pfeilsticker IUP Heidelberg. Ozone depleting substances (ODS) are no longer increasing but slowly dropping since 2000: Montreal Protocol et al. is working!!! But detection of the expected recovery still needs time and especially the continuation of high- quality long-term ozone observations!!!

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 8 Results of modelling/laboratory research Fig. 21: New laboratory ozone absorption cross-section shown in the Huggins band. Indicated are also the operational Brewer and Dobson wavelengths. (Plot from Serdyuchenko, IUP Introduction of new ozone cross sections: Suspension necessary after latest results in laboratory measurements. IUP x- sections provide more consistent data between Dobson and Brewer than the originally recommended Brion- Daumont-Malicet X- sections. Determination of temp.-dep. necessary

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 9 Calibration Centers WCCOS (World Calibration Center for Ozone Sondes) in Jülich: 1) O3Sonde-DQA (SI2N = SPARC, ICAGOO34, IO3C, NDACC): Homogenization of O3S-records (several JOSIE campaigns since 1996) 2) Implementation SOPs in the O3S-Network(s): GAW Report 201 (Quality Assurance and Quality Control for Ozonesonde Measurements in GAW) published in ) Collaboration with GRUAN (GCOS Reference Upper-Air Network): Guidelines for deriving uncertainties as operational tool 4) Plans for workshop on O3S-DQA: Homogenization & Early ) JOSIE 2015/16 in collaboration with SHADOZ

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 10 Calibration Centers Situation still stable - retirement of Hans and Karel in 2014 Situation still stable, Bob‘s retirement in 2014!!! Glen McConville as successor Head Matt Tully Future O.K. Future confirmed Situation stable, still needs techn. support Global Dobson Calibration System

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 11 operational (RA VI): 23 in Antarctica: 2 spare: 1(3) not operat.: 6 in total: 35 standards: 2 transfered: 4 for transfer: 1+5 D035 to South AfricaD056 to Uganda European Dobson Network and RDCC

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 12 Summary of the RDCC-E-Activities /4 Calibr. Regional-Standards:11 (D064) & 6 (D074) (incl. 4 Langley-Calibr.) Calibration Campaigns:39 (24 MOHp + 7 other locations) (Organization or participation)for 135 Dobsons (27 countries) 76 at MOHp from (22 countries) Other campaigns:2 (Comp. with Satellite-instr. etc.) Refurbishment (new electr. etc.):28 Dobsons Relocation: 4 Dobsons + 1, 3 planned Training:21 Stationen (SOO-HK) Software:25 Stationen (SOO-HK) Data examination/reeval.:12 Stationen (SOO-HK)

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 13 Success of the Dobson Calibration System Improvement of data quality since beginning of regular calibrations (every four years recommended) since the 1980ties

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 14 Success of the Dobson Calibration System Due to reduction of financial and personnel resources the calibration cycle has been modified from 4 up to 5-6 years: Results still good

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 15 Success of the Dobson Calibration System Due to reduction of financial and personnel resources the calibration cycle has officially been modified from 4 up to 5-6 years: Results still good

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 16 Data Center The WDC-RSAT (World Data Center for Remote Sensing of the Atmosphere, operated by the DLR in Oberpfaffenhofen, Germany) is the most recent data center in the WMO-WDC family. Ozone total column observations from MetOp-A/GOME-2 for 1st of February 2014 (L3 product). WDC- RSAT map viewer is assessable at under “Map Viewer”.

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 17 Projects and Collaborations Too many projects and collaborations to be presented here, so please check the German National Report

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 18 NEEDS AND RECOMMENDATIONS I - Continuing high-quality measurements of total ozone and ozone profiles by satellites on the global scale and by ground-based systems incl. UV have to be insured for the next decades. Relocations of Dobsons will improve the network! - New limb/occultation satellite mission is needed as number of limb satellites will decline. This might cause gaps and results in a loss of satellite date with vertical resolution. Therefore the availability of space- borne infrared limb emission instruments after MIPAS is essential for future ozone research. - Quality Assurance/Quality Control activities like calibration centres must be supported to maintain the high quality standards of the ground stations especially in times of limited budgets; reduction of Dobson calibration frequency is reasonable to lower costs. The continuation is necessary for satellite validation, ozone monitoring and trend analyses. MoU between DWD and SAWS on RDCC twinning activity is considered!

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 19 NEEDS AND RECOMMENDATIONS II - The complex coupling of ozone, atmospheric chemistry, transports and climate changes is still not fully understood. Further research is needed to better understand the underlying processes and to improve model predictions of the expected substantial changes in both ozone and temperature distributions of the middle atmosphere. - In this context, there is a need for better and more consistent long-term temperature data in the stratosphere. - The current process of final determination and implementation of new ozone cross-section/absorption coefficients should get highest priority to obtain consistency between the various instruments either ground-based or satellite-borne. The ACSO activities should be fostered, that they come to a successful end as soon as possible!!!

9.Meeting of the Ozone Research Managers of the Parties to the Vienna Convention, Geneva, May 214, Ulf Köhler/DWD page 20 Rough methods to calibrate and align Dobsons MOHp campaign at Hohenpeissenberg Thanks for your attention