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Unsupervised classification of snowflake images using a generative adversarial network and K-medoids classification

Atmos.Meas.Tech. discussions - Fri, 06/05/2020 - 17:44
Unsupervised classification of snowflake images using a generative adversarial network and

Correcting high-frequency losses of reactive nitrogen flux measurements

Atmos.Meas.Tech. discussions - Fri, 06/05/2020 - 13:39
Correcting high-frequency losses of reactive nitrogen flux measurements
Pascal Wintjen, Christof Ammann, Frederik Schrader, and Christian Brümmer
Atmos. Meas. Tech., 13, 2923–2948, https://doi.org/10.5194/amt-13-2923-2020, 2020
With recent technological advances it is now possible to measure the exchange of trace gases between the land surface and the atmosphere. When using the so-called eddy-covariance method, certain corrections need to be applied to account for attenuation in the flux signal. These losses were found to be setup- and site-specific and can be up to 38 % for reactive nitrogen fluxes. We evaluated five different methods and recommend using an empirical version with locally measured cospectra.

Correcting high-frequency losses of reactive nitrogen flux measurements

Correcting high-frequency losses of reactive nitrogen flux measurements
Pascal Wintjen, Christof Ammann, Frederik Schrader, and Christian Brümmer
Atmos. Meas. Tech., 13, 2923–2948, https://doi.org/10.5194/amt-13-2923-2020, 2020
With recent technological advances it is now possible to measure the exchange of trace gases between the land surface and the atmosphere. When using the so-called eddy-covariance method, certain corrections need to be applied to account for attenuation in the flux signal. These losses were found to be setup- and site-specific and can be up to 38 % for reactive nitrogen fluxes. We evaluated five different methods and recommend using an empirical version with locally measured cospectra.

A novel injection technique: using a field-based quantum cascade laser for the analysis of gas samples derived from static chambers

Atmos.Meas.Tech. discussions - Thu, 06/04/2020 - 19:07
A novel injection technique: using a field-based quantum cascade laser for the analysis of gas samples derived from static chambers
Anne R. Wecking, Vanessa M. Cave, Lìyĭn L. Liáng, Aaron M. Wall, Jiafa Luo, David I. Campbell, and Louis A. Schipper
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-197,2020
Preprint under review for AMT (discussion: open, 0 comments)
Nitrous oxide (N

A novel injection technique: using a field-based quantum cascade laser for the analysis of gas samples derived from static chambers

A novel injection technique: using a field-based quantum cascade laser for the analysis of gas samples derived from static chambers
Anne R. Wecking, Vanessa M. Cave, Lìyĭn L. Liáng, Aaron M. Wall, Jiafa Luo, David I. Campbell, and Louis A. Schipper
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-197,2020
Preprint under review for AMT (discussion: open, 0 comments)
Nitrous oxide (N

Resolving the size of ice-nucleating particles with a balloon deployable aerosol sampler: the SHARK

Atmos.Meas.Tech. discussions - Wed, 06/03/2020 - 17:06
Resolving the size of ice-nucleating particles with a balloon deployable aerosol sampler: the SHARK
Grace C. E. Porter, Sebastien N. F. Sikora, Michael P. Adams, Ulrike Proske, Alexander D. Harrison, Mark D. Tarn, Ian M. Brooks, and Benjamin J. Murray
Atmos. Meas. Tech., 13, 2905–2921, https://doi.org/10.5194/amt-13-2905-2020, 2020
Ice-nucleating particles affect cloud development, lifetime, and radiative properties. Hence it is important to know the abundance of INPs throughout the atmosphere. Here we present the development and application of a radio-controlled payload capable of collecting size-resolved aerosol from a tethered balloon for the primary purpose of offline INP analysis. Test data are presented from four locations: southern Finland, northern England, Svalbard, and southern England.

Resolving the size of ice-nucleating particles with a balloon deployable aerosol sampler: the SHARK

Resolving the size of ice-nucleating particles with a balloon deployable aerosol sampler: the SHARK
Grace C. E. Porter, Sebastien N. F. Sikora, Michael P. Adams, Ulrike Proske, Alexander D. Harrison, Mark D. Tarn, Ian M. Brooks, and Benjamin J. Murray
Atmos. Meas. Tech., 13, 2905–2921, https://doi.org/10.5194/amt-13-2905-2020, 2020
Ice-nucleating particles affect cloud development, lifetime, and radiative properties. Hence it is important to know the abundance of INPs throughout the atmosphere. Here we present the development and application of a radio-controlled payload capable of collecting size-resolved aerosol from a tethered balloon for the primary purpose of offline INP analysis. Test data are presented from four locations: southern Finland, northern England, Svalbard, and southern England.

XCO2 estimates from the OCO-2 measurements using a neural network approach

Atmos.Meas.Tech. discussions - Tue, 06/02/2020 - 18:56
XCO2 estimates from the OCO-2 measurements using a neural network approach
Leslie David, Francois-Marie Bréon, and Frédéric Chevallier
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-177,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper shows that a Neural Network approach can be used to process spaceborne observations from the OCO-2 satellite and retrieve both the surface pressure and the atmospheric CO

XCO2 estimates from the OCO-2 measurements using a neural network approach

XCO2 estimates from the OCO-2 measurements using a neural network approach
Leslie David, Francois-Marie Bréon, and Frédéric Chevallier
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-177,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper shows that a Neural Network approach can be used to process spaceborne observations from the OCO-2 satellite and retrieve both the surface pressure and the atmospheric CO

Assessment of global total column water vapor sounding using a spaceborne differential absorption radar

Atmos.Meas.Tech. discussions - Tue, 06/02/2020 - 17:06
Assessment of global total column water vapor sounding using a spaceborne differential absorption radar
Luis Millán, Richard Roy, and Matthew Lebsock
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-97,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper describes the feasibility of using a differential absorption radar technique for the remote sensing of total column water vapor from a spaceborne platform.

Assessment of global total column water vapor sounding using a spaceborne differential absorption radar

Assessment of global total column water vapor sounding using a spaceborne differential absorption radar
Luis Millán, Richard Roy, and Matthew Lebsock
Atmos. Meas. Tech. Discuss., https//doi.org/10.5194/amt-2020-97,2020
Preprint under review for AMT (discussion: open, 0 comments)
This paper describes the feasibility of using a differential absorption radar technique for the remote sensing of total column water vapor from a spaceborne platform.

Development of a new correction algorithm applicable to any filter-based absorption photometer

Atmos.Meas.Tech. discussions - Fri, 05/29/2020 - 18:56
Development of a new correction algorithm applicable to any filter-based absorption photometer
Hanyang Li, Gavin R. McMeeking, and Andrew A. May
Atmos. Meas. Tech., 13, 2865–2886, https://doi.org/10.5194/amt-13-2865-2020, 2020
We present a new correction algorithm that addresses biases in measurements of aerosol light absorption by filter-based photometers, incorporating the transmission of light through the filter and some aerosol optical properties. It was developed using biomass burning aerosols and tested using rural ambient aerosols. This new algorithm is applicable to any filter-based photometer, resulting in good agreement between different colocated instruments in both the laboratory and the field.

Methodology for deriving the telescope focus function and its uncertainty for a heterodyne pulsed Doppler lidar

Atmos.Meas.Tech. discussions - Fri, 05/29/2020 - 18:56
Methodology for deriving the telescope focus function and its uncertainty for a heterodyne pulsed Doppler lidar
Pyry Pentikäinen, Ewan James O'Connor, Antti Juhani Manninen, and Pablo Ortiz-Amezcua
Atmos. Meas. Tech., 13, 2849–2863, https://doi.org/10.5194/amt-13-2849-2020, 2020
We provide a methodology for obtaining a function describing how the Doppler lidar telescope configuration impacts the measurements. Together with the function itself, we also provide the uncertainties in the function, which propagate through to provide uncertainties in the geophysical quantities obtained from the measurements. The method can be used to determine how stable the instrument is over time and also identify if changes have been made in the instrument setup.

The CopterSonde: an insight into the development of a smart unmanned aircraft system for atmospheric boundary layer research

Atmos.Meas.Tech. discussions - Fri, 05/29/2020 - 18:56
The CopterSonde: an insight into the development of a smart unmanned aircraft system for atmospheric boundary layer research
Antonio R. Segales, Brian R. Greene, Tyler M. Bell, William Doyle, Joshua J. Martin, Elizabeth A. Pillar-Little, and Phillip B. Chilson
Atmos. Meas. Tech., 13, 2833–2848, https://doi.org/10.5194/amt-13-2833-2020, 2020
The CopterSonde is an unmanned aircraft system designed with the purpose of sampling thermodynamic and kinematic parameters of the lower Earth's atmosphere, with a focus on vertical profiles in the planetary boundary layer. By incorporating adaptive sampling techniques and optimizing the sensor placement, our study shows that CopterSonde can provide similar information as a radiosonde, but with more control of its sampling location at much higher temporal and spatial resolution.

Understanding cryogenic frost point hygrometer measurements after contamination by mixed-phase clouds

Atmos.Meas.Tech. discussions - Fri, 05/29/2020 - 18:56
Understanding cryogenic frost point hygrometer measurements after contamination by mixed-phase clouds
Teresa Jorge, Simone Brunamonti, Yann Poltera, Frank G. Wienhold, Bei P. Luo, Peter Oelsner, Sreeharsha Hanumanthu, Bhupendra B. Sing, Susanne Körner, Ruud Dirksen, Manish Naja, Suvarna Fadnavis, and Thomas Peter
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-176,2020
Preprint under review for AMT (discussion: open, 0 comments)
Balloon-borne frost point hygrometers are crucial for the monitoring of water vapour in the upper troposphere and lower stratosphere. We found that when traversing a mixed-phase cloud with big supercooled droplets, the intake tube of the instrument collects on its inner surface a high percentage of these droplets. The newly formed ice layer will sublimate at higher levels and contaminate the measurement. The balloon and instrument package are also investigated as source of the contamination.

Development of a new correction algorithm applicable to any filter-based absorption photometer

Development of a new correction algorithm applicable to any filter-based absorption photometer
Hanyang Li, Gavin R. McMeeking, and Andrew A. May
Atmos. Meas. Tech., 13, 2865–2886, https://doi.org/10.5194/amt-13-2865-2020, 2020
We present a new correction algorithm that addresses biases in measurements of aerosol light absorption by filter-based photometers, incorporating the transmission of light through the filter and some aerosol optical properties. It was developed using biomass burning aerosols and tested using rural ambient aerosols. This new algorithm is applicable to any filter-based photometer, resulting in good agreement between different colocated instruments in both the laboratory and the field.

Methodology for deriving the telescope focus function and its uncertainty for a heterodyne pulsed Doppler lidar

Methodology for deriving the telescope focus function and its uncertainty for a heterodyne pulsed Doppler lidar
Pyry Pentikäinen, Ewan James O'Connor, Antti Juhani Manninen, and Pablo Ortiz-Amezcua
Atmos. Meas. Tech., 13, 2849–2863, https://doi.org/10.5194/amt-13-2849-2020, 2020
We provide a methodology for obtaining a function describing how the Doppler lidar telescope configuration impacts the measurements. Together with the function itself, we also provide the uncertainties in the function, which propagate through to provide uncertainties in the geophysical quantities obtained from the measurements. The method can be used to determine how stable the instrument is over time and also identify if changes have been made in the instrument setup.

The CopterSonde: an insight into the development of a smart unmanned aircraft system for atmospheric boundary layer research

The CopterSonde: an insight into the development of a smart unmanned aircraft system for atmospheric boundary layer research
Antonio R. Segales, Brian R. Greene, Tyler M. Bell, William Doyle, Joshua J. Martin, Elizabeth A. Pillar-Little, and Phillip B. Chilson
Atmos. Meas. Tech., 13, 2833–2848, https://doi.org/10.5194/amt-13-2833-2020, 2020
The CopterSonde is an unmanned aircraft system designed with the purpose of sampling thermodynamic and kinematic parameters of the lower Earth's atmosphere, with a focus on vertical profiles in the planetary boundary layer. By incorporating adaptive sampling techniques and optimizing the sensor placement, our study shows that CopterSonde can provide similar information as a radiosonde, but with more control of its sampling location at much higher temporal and spatial resolution.

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