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Fiducial Reference Measurements for Ground-Based IR Greenhouse Gas Observation (FRM4GHG). J. Notholt, M. De Mazière, R. Kivi, H. Chen, T. Blumenstock, D. Griffith, D. Weidmann and co-workers
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Fiducial Reference Measurements for Ground-Based IR Greenhouse Gas Observation (FRM4GHG) J. Notholt, M. De Mazière, R. Kivi, H. Chen, T. Blumenstock, D. Griffith, D. Weidmann and co-workers University of Bremen, Royal Belgian Institute for Space Aeronomy, Finnish Meteorological Institute, University of Groningen, Karlsruhe Institute of Technology, University of Wollongong, Rutherford Appleton Laboratory Institute of Environmental Physics University of Bremen
Current situation and requirements Optimum validation for NADIR satellite observations of GHGs is provided by ground-based solar absorption spectrometry - TCCON is the reference system - Complete TCCON observation system (container, Bruker 125 HR, solar tracker) is expensive 400-500 k€ - Requires high maintenance and operations costs - Difficult to transport, limits possibility for campaigns - Limits the extension of the network Development of cheaper and easier deployable systems for remote sensing GHG observations
Aim of FRM4GHG Perform an intercomparison of measured total column concentrations of a few GHG (CO2, CH4, CO) using several different infrared spectrometric instruments at a TCCON site. We plan to perform measurements with five different spectrometers plus the in-situ Aircore balloon system The measurement campaign is planned to take place in Sodankyla/Finland in 2017. Project starts in Aug. 2016. FMI runs there a TCCON instrument and has experience with AirCore launches (allowed in Sodankyla !) since September 2013.
Instruments for FRM4GHG TCCON Bruker 125HR (FMI) XCO2, XCH4, XCO; resol. 0.02 cm-1 Bruker EM27/SUN (KIT) XCO2, XCH4; resol. 0.5 cm-1 + dual channel version XCO Bruker Vertex 70 (BIRA & IUP) XCO2, XCH4 , XCO; resol. 0.16 cm-1 IR cube (UoW) XCO2, XCH4, XCO; very low resol. Quantum cascade later heterodyne radiometer (RAL) CH4, CO, CO2; resol. 0.005 cm-1 In-situ Aircore system (RUG) CO2, CH4, CO vertical profiles Calibrated to WMO standards
FRM4GHG campaign set-up South Tracker C: Hole in the wall 5 cm, 1 meter from inside floor D: Hole in the wall 5 cm, at 2.2 m E: Hole in the wall 5 cm, at 2.2 m IR Cube QCLHR EM27/SUN A: Hole in the roof: 20 cm Tracker; B: 5 cm cables F: Internet RACK, 19 inches, inside, on the wall Vertex 70 Cables inlet: power cable, ethernet cable Ilmalämpöpumppu Window, 0.82*1.1m Window, 0.82*1.1m Double door
Bruker Vertex 70 EM27/SUN IR cube
Aircore QCLHR
Work packages within FRM4GHG WP0: Preparation of container to host the spectrometers (not financed by ESA) WP1: Requirements Identification WP2: Intercomparison Preparation (end of 2016) WP3: Intercomparison Execution (2017) - semi-blind comparison WP4: Data analysis and Corrective Measures including aircore profiles as a priori WP5: Project Outreach - conclusions - involvement of satellite groups, NDACC & TCCON WP6: Development of an AirCore Gliding System (optional, depending on funding) WP7: Project management
Ny-Ǻlesundissue (Christoph Petri) Sometimeswefoundinconsistenciesbetweenforward- andbackward-runs fortheupgradedinstrumentusing TCCON splittingsoftware i2s (forward/backwardinterferogram) Institute of Environmental Physics University of Bremen
Nobiasfor OPUS-splittedforward- andbackwardspectra • Problem due tosplittingintoforward/backward in i2s Institute of Environmental Physics University of Bremen
Biggestdifferencesfound in the O2-retrieval • Effecthardlyvisible in the CO2retrieval Institute of Environmental Physics University of Bremen
Forthosewrongretrievalsspectrashowwave-likestructure • Position of ZPD ? Phase correction in slice-i2s mightbetheproblem ? 15.000 10.000 Institute of Environmental Physics University of Bremen
A Python module for Opus files and slices Matthias Buschmann, IUP Bremen Problem: - Opus files and slices not server-side accessible - Access to ifg/spc via conversion to ascii only - For limited data transfer from remote sites (e.g. Palau): Check interferograms before transfer Solution: - GGG/i2s has all necessary infos to look at spectra/slices/header - Implemented in Python using standard libraries + NumPy - Access to slices, spectra and interferograms - Full header information access
Example - First line: how to install the module in Python - Second line: open a spectrum - Rest: how to get OPUS Header infos - Replacement of data blocks and header parameters possible
Slices Interferogram Spectrum