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Balloon-borne mid-infrared laser spectroscopy for in-situ water vapor measurements in the Upper Troposphere and Lower Stratosphere

English title Balloon-borne mid-infrared laser spectroscopy for in-situ water vapor measurements in the Upper Troposphere and Lower Stratosphere
Applicant Tuzson Béla
Number 157208
Funding scheme Project funding
Research institution Luftfremdstoffe / Umwelttechnik 500 - Mobility, Energy and Environment EMPA
Institution of higher education Swiss Federal Laboratories for Materials Science and Technology - EMPA
Main discipline Climatology. Atmospherical Chemistry, Aeronomy
Start/End 01.02.2015 - 31.07.2019
Approved amount 263'396.00
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All Disciplines (2)

Discipline
Climatology. Atmospherical Chemistry, Aeronomy
Other disciplines of Physics

Keywords (5)

balloon-borne measurements; laser absorption spectroscopy; Wasserdampf; UT/LS; Hygrometer

Lay Summary (German)

Lead
Wasserdampf ist eine der wichtigsten Bestandteile der Atmosphäre. In der Region der oberen Troposphäre/unteren Stratosphäre (UT/LS) hat Wasserdampf, aufgrund seiner Strahlungseigenschaften, eine entscheidende Rolle im Klimasystem inne. Genaue und zuverlässige Wasserdampfmessungen sind deshalb für das Verständnis vieler atmosphärischer Prozesse, Strahlungstransfer Rechnungen, Wolkenbildungsprozesse und Klimatrendstudien unerlässlich. Dennoch bestehen immer noch erhebliche Diskrepanzen zwischen einzelnen Methoden und Instrumenten.
Lay summary

Inhalt und Ziele

Im vorliegenden Projekt wird ein neuartiges und kompaktes Laser-Hygrometer für die genaue Messung niedriger Wasserdampfkonzentrationen in der UT/LS entwickelt. Als Messverfahren wird Laser-Absorptionsspektroskopie im mittleren Infrarotbereich eingesetzt, auf der Basis eines Quantenkaskadenlasers. Diese Technik kombiniert sehr hohe Selektivität mit ausgezeichnete Empfindlichkeit und Ansprechzeit. Für die anspruchsvollen Flüge an Bord eines Wetterballons in der UT/LS müssen zahlreiche Speziallösungen im Bereich Optik, Elektronik und Mechanik entwickelt und erprobt werden.

In enger Zusammenarbeit der Empa (Abteilung Luftfremdstoffe/Umwelttechnik), der ETHZ (Institut für Atmosphäre und Klima) und MeteoSchweiz wird das Instrument charakterisiert und validiert. Anschliessend werden erste Ballonmessungen durchgeführt und die Messdaten mit bisher verfügbaren Methoden verglichen.

Direct link to Lay Summary Last update: 24.02.2015

Responsible applicant and co-applicants

Employees

Publications

Publication
Compact and lightweight mid-infrared laser spectrometer for balloon-borne water vapor measurements in the UTLS
Graf Manuel, Scheidegger Philipp, Kupferschmid André, Looser Herbert, Peter Thomas, Dirksen Ruud, Emmenegger Lukas, Tuzson Béla (2021), Compact and lightweight mid-infrared laser spectrometer for balloon-borne water vapor measurements in the UTLS, in Atmospheric Measurement Techniques, 14(2), 1365-1378.
A compact QCL spectrometer for mobile, high-precision methane sensing aboard drones
Tuzson Béla, Graf Manuel, Ravelid Jonas, Scheidegger Philipp, Kupferschmid André, Looser Herbert, Morales Randulph Paulo, Emmenegger Lukas (2020), A compact QCL spectrometer for mobile, high-precision methane sensing aboard drones, in Atmospheric Measurement Techniques, 13(9), 4715-4726.
Laser driving and data processing concept for mobile trace gas sensing: Design and implementation
Liu Chang, Tuzson Béla, Scheidegger Philipp, Looser Herbert, Bereiter Bernhard, Graf Manuel, Hundt Morten, Aseev Oleg, Maas Deran, Emmenegger Lukas (2018), Laser driving and data processing concept for mobile trace gas sensing: Design and implementation, in Review of Scientific Instruments, 89(6), 065107-065107.
Compact, circular, and optically stable multipass cell for mobile laser absorption spectroscopy
Graf Manuel, Emmenegger Lukas, Tuzson Béla (2018), Compact, circular, and optically stable multipass cell for mobile laser absorption spectroscopy, in Optics Letters, 43(11), 2434-2434.
QCL absorption spectroscopy for lightweight and multi-species environmental applications
Emmenegger Lukas, Stanicki Badrudin, Graf Manuel, Scheidegger Philipp, Hundt Morten, Faist Jérôme, Kapsalidis Filippos, Looser Herbert, Shahmohammadi Mehran, Tuzson Béla QCL absorption spectroscopy for lightweight and multi-species environmental applications, (2018), QCL absorption spectroscopy for lightweight and multi-species environmental applications, OSA Publishing, USA.
Beam folding analysis and optimization of mask-enhanced toroidal multipass cells
Graf Manuel, Looser Herbert, Emmenegger Lukas, Tuzson Béla (2017), Beam folding analysis and optimization of mask-enhanced toroidal multipass cells, in Optics Letters, 42(16), 3137-3137.

Collaboration

Group / person Country
Types of collaboration
Alpes Lasers SA, Dr. Antoine Müller Switzerland (Europe)
- Industry/business/other use-inspired collaboration
METAS Switzerland (Europe)
- Research Infrastructure
GRUAN Network Germany (Europe)
- in-depth/constructive exchanges on approaches, methods or results
ETHZ, Quantum Optoelectronics, Prof. J. Faist Switzerland (Europe)
- in-depth/constructive exchanges on approaches, methods or results

Scientific events

Active participation

Title Type of contribution Title of article or contribution Date Place Persons involved
EGU - 2020 Talk given at a conference Mid-IR Laser Spectrometer for Balloon-borne Lower Stratospheric Water Vapor Measurements 04.05.2020 Wien, Austria Graf Manuel; Emmenegger Lukas; Tuzson Béla; Peter Thomas;
17th Swiss Geoscience Meeting Talk given at a conference Mid-IR Laser Spectrometer for Balloon-borne Lower Stratospheric Water Vapor Measurements 22.11.2019 Fribourg, Switzerland Tuzson Béla; Graf Manuel; Peter Thomas; Emmenegger Lukas;
PIERS - PhotonIcs & Electromagnetics Research Symposium Talk given at a conference Tracking molecules from the ground to the sky. Multi-wavelength QCLs in mobile analyzers 17.06.2019 Rome, Italy Graf Manuel; Tuzson Béla; Emmenegger Lukas;
Industrial Methane Measurement Conference Talk given at a conference A high-precision laser spectrometer for methane monitoring aboard UAVs 22.05.2019 Rotterdam, Netherlands Graf Manuel; Tuzson Béla; Emmenegger Lukas;
CLEO - Conference on Lasers and Electro-Optics Talk given at a conference Mid-IR laser spectrometer for balloon-borne lower stratospheric water vapor measurements 05.05.2019 San Jose, United States of America Graf Manuel; Emmenegger Lukas; Peter Thomas; Tuzson Béla;
EGU - 2019 Talk given at a conference A compact QCL absorption spectrometer for mobile, high-precision methane measurements aboard drones 11.04.2019 Wien, Austria Graf Manuel; Tuzson Béla; Emmenegger Lukas;
OSA - Light, Energy and the Environment Congress Talk given at a conference QCL absorption spectroscopy for lightweight and multi-species environmental applications 05.11.2018 Singapore, Singapore Emmenegger Lukas; Tuzson Béla; Graf Manuel;
FLAIR - Field Laser Applications in Industry and Research Talk given at a conference A compact QCL absorption spectrometer for mobile, high-precision methane measurements aboard drones 10.09.2018 Assisi, Italy Emmenegger Lukas; Tuzson Béla; Graf Manuel;
FLAIR - Field Laser Applications in Industry and Research Poster Optically stable circular multipass cell for compact and lightweight absorption spectrometers 10.09.2018 Assisi, Italy Tuzson Béla; Graf Manuel; Emmenegger Lukas;
EGU - 2018 Talk given at a conference Optically stable circular multipass cell for compact and lightweight absorption spectroscopy 08.04.2018 Wien, Austria Graf Manuel; Tuzson Béla; Emmenegger Lukas;
Mirsense 4 Talk given at a conference Compact and Lightweigth Multipass Cell Design with Optimized Beam Propagation 15.05.2017 Wroclaw, Poland Tuzson Béla; Emmenegger Lukas; Graf Manuel;
FLAIR - Field Laser Applications in Industry and Research Poster Compact FPGA based data acquisition for mobile QCLAS applications 12.09.2016 Aix-les-Bains, France Tuzson Béla; Emmenegger Lukas;


Associated projects

Number Title Start Funding scheme
176584 High-resolution QCL frequency comb spectrometer for the detection of trace gases and their isotopes 01.05.2018 Bridge - Discovery

Abstract

Accurate and reliable measurements of water vapor in the Upper Troposphere and Lower Stratosphere (UT/LS) are needed for a wide range of applications, such as forecast modeling, radiative transfer calculations and climate trend studies. Furthermore, water vapor plays an important role in stratospheric dehydration, troposphere-stratosphere exchange processes, and the formation of cirrus clouds. At present, however, UT/LS water vapor distributions are not well understood.In situ humidity measurements in the UT/LS can be performed with hygrometers using a large variety of techniques, such as chilled mirrors, the Lyman-a technique, and tunable diode laser spectroscopy. Recent field campaigns have provided clear evidence for large deviations between hygrometers, rendering them questionable for useful determination of relative humidity at lower water vapor content (few ppm), such as found in the LS. Intercomparisons of state-of-the-art and prototype hygrometers in aerosol and cloud chambers under controlled conditions have further revealed serious discrepancies, neither explaining the errors fully nor suggesting a solution to the problem.Laser absorption spectroscopy in the mid-infrared is a rapidly evolving technique that combines very high selectivity, sensitivity and time response. In the frame of this project we propose to develop a lightweight quantum cascade laser based spectroscopic setup for measuring atmospheric H2O in the UT/LS. Our aim is to explore new limits for sensitivity and precision, and to show the feasibility of in situ H2O measurements by laser absorption spectroscopy onboard a meteorological balloon. The ultimate goal is to measure water vapor with better than 4 % accuracy at 1 s time resolution for mixing rations of a few parts-per-million (ppm), i.e. even under stratospheric conditions of up to 20 km altitude, at a temperature of about 180 K and a pressure below 60 hPa.In order to achieve this ambitious goal, we propose a direct absorption approach based on a novel, open ring-shaped multipass-cell design, a mid-infrared quantum cascade laser, our intermittent low-dissipation laser driving electronics, and FPGA based data acquisition. This combination offers an outstanding and unique solution to obtain the necessary signal-to-noise ratio required for water vapor measurements in the UT/LS.The project is based on the work of a PhD student and the strong competence in laser spectroscopy and trace gas monitoring of Empa. For instrument validation, inter-laboratory and in-flight comparisons with established chilled mirror hygrometers will be performed in collaboration with IACETH and MeteoSwiss.
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