AMT - recent papers

Dynamic quantification of methane emissions at facility scale using laser tomography: demonstration of a farm deployment

2026-04-10T11:37:12+02:00

Dynamic quantification of methane emissions at facility scale using laser tomography: demonstration of a farm deployment
Kenneth Scheel, Elias Vänskä, Damien Weidmann, and Aku Ursin
Atmos. Meas. Tech., 19, 2343–2367, https://doi.org/10.5194/amt-19-2343-2026, 2026
We present a laser-based tomographic approach for dynamically quantifying and mapping greenhouse gas emissions at facility scale. It was applied during a campaign at a research farm in Eastern Finland, where methane emissions from typical manure-handling events were monitored. The results show that incorporating prior information on source locations improves the tolerance of the flux estimates with respect to environmental disturbances.

Modification and validation of a commercial dynamic chamber for reactive nitrogen and greenhouse gas flux measurements

2026-04-10T11:37:12+02:00

Modification and validation of a commercial dynamic chamber for reactive nitrogen and greenhouse gas flux measurements
Moxy Shah, Kifle Z. Aregahegn, Danial Nodeh-Farahani, Leigh R. Crilley, Tasnia Hasan, Yashar Ebrahimi-Iranpour, Fahim Sarker, Nick Nickerson, Chance Creelman, Sarah Ellis, Alexander Moravek, and Trevor C. VandenBoer
Atmos. Meas. Tech., 19, 2379–2405, https://doi.org/10.5194/amt-19-2379-2026, 2026
A commercial dynamic chamber system is modified to measure reactive nitrogen and greenhouse gas fluxes of interest for climate and air quality. The system is optimized for high performance so that fluxes of surface-active gases like ammonia, or reactive gases like nitrogen dioxide, can be made robustly. Lab and field measurements demonstrate consistent fluxes with those from other in-situ agricultural soil reports, as these are expected hot spots of reactive nitrogen gas exchange.

Simultaneous measurements of near-surface CO2 and NO2 to monitor the fossil-fuel combustion-derived CO2 in the Greater Tokyo Area

2026-04-10T11:37:12+02:00

Simultaneous measurements of near-surface CO2 and NO2 to monitor the fossil-fuel combustion-derived CO2 in the Greater Tokyo Area
Hitoshi Irie, Masataka Nomoto, Yoshikazu Kamiya, and Yukio Terao
Atmos. Meas. Tech., 19, 2369–2378, https://doi.org/10.5194/amt-19-2369-2026, 2026
Continuous year-round measurements in Chiba, Japan, combining in‑situ CO2 observations with MAX‑DOAS (Multi-Axis Differential Optical Absorption Spectroscopy) NO2, showed that CO2 levels decrease on days with low near-surface NO2. CO2 enhancements quantified using these low-NO2 days correlated strongly with NO₂ and black carbon, indicating that this metric effectively tracks fossil-fuel-derived CO₂. The approach offers a simple, accurate method for monitoring urban CO2 emissions in megacities.

Laminar gas inlet – Part 2: Wind tunnel chemical transmission measurement and modelling

2026-04-09T11:37:12+02:00

Laminar gas inlet – Part 2: Wind tunnel chemical transmission measurement and modelling
Da Yang, Emmanuel Assaf, Roy Mauldin, Suresh Dhaniyala, and Rainer Volkamer
Atmos. Meas. Tech., 19, 2329–2342, https://doi.org/10.5194/amt-19-2329-2026, 2026
Sulfuric acid forms particles in the atmosphere, but the airborne sampling faces challenges due to vapor losses in inlet lines. An innovative aircraft sampling system to sample sulfuric acid from the sea surface into the lower stratosphere (0–15 km) is described and characterized. Our results challenge the widely held view that laminar core sampling is the best strategy to sample condensable vapors, and identify better strategies to sample condensable vapors.

First results of SO2 columns from FY-3F/OMS instrument observations

2026-04-09T11:37:12+02:00

First results of SO2 columns from FY-3F/OMS instrument observations
Huanhuan Yan, Andreas Richter, Xingying Zhang, Anja Schönhardt, Thomas Visarius, Qian Wang, Lu Zhang, Yichen Li, Chao Yu, and Weihe Wang
Atmos. Meas. Tech., 19, 2279–2311, https://doi.org/10.5194/amt-19-2279-2026, 2026
The Ozone Monitoring Suite (OMS) launched in August 2023 is a new Chinese hyperspectral UV-VIS (Ultraviolet-Visible) instrument. This study used the OMS measurements and Differential Optical Absorption Spectroscopy (DOAS) inversion to for the first time retrieve global SO2 columns from OMS. The results show that the OMS SO2 retrievals exhibit good stability over clean oceanic regions, successfully capture volcanic SO2 plumes, and effectively detect the elevated SO2 columns from anthropogenic emissions.

The estimation of path integrated attenuation for the EarthCARE cloud profiling radar

2026-04-09T11:37:12+02:00

The estimation of path integrated attenuation for the EarthCARE cloud profiling radar
Susmitha Sasikumar, Alessandro Battaglia, Bernat Puigdomènech Treserras, and Pavlos Kollias
Atmos. Meas. Tech., 19, 2313–2328, https://doi.org/10.5194/amt-19-2313-2026, 2026
The study present a method to estimate how much the radar signal is weakened as it passes through rain or clouds, designed to implement in the new EarthCARE satellite cloud profiling radar data. The approach builds on the method used in the CloudSat mission, with key improvements that make it robust under non-ideal instrument conditions in the early mission phase. This leads to more reliable retrieval of clouds and rainfall during initial satellite operations.

Fast and reproducible δ13C-CO2 analysis from 1 mL of ambient atmospheric air using continuous-flow IRMS: from sampling to storage to analysis

2026-04-01T11:37:12+02:00

Fast and reproducible δ13C-CO2 analysis from 1 mL of ambient atmospheric air using continuous-flow IRMS: from sampling to storage to analysis
Joana Sauze, Marie-Laure Tiouchichine, Alexandru Milcu, and Clément Piel
Atmos. Meas. Tech., 19, 2265–2277, https://doi.org/10.5194/amt-19-2265-2026, 2026
We present a simple workflow for high-precision δ¹³C-CO₂ analysis from 1 mL air samples using cryogenic pre-concentration and continuous-flow isotope-ratio mass spectrometry (IRMS). The method combines vial conditioning, dual sealing, and −80 °C storage to minimise gas loss. It achieves ±0.1 ‰ precision and stable isotopic values for up to one week of storage. This low-cost approach enables high-frequency δ¹³C-CO₂ measurements in volume-limited systems such as microcosm or chamber experiments.

Cloud liquid water path detectability and retrieval accuracy from airborne passive microwave observations over Arctic sea ice

2026-04-01T11:37:12+02:00

Cloud liquid water path detectability and retrieval accuracy from airborne passive microwave observations over Arctic sea ice
Nils Risse, Mario Mech, Catherine Prigent, Joshua J. Müller, and Susanne Crewell
Atmos. Meas. Tech., 19, 2197–2223, https://doi.org/10.5194/amt-19-2197-2026, 2026
Clouds play a crucial role in the Arctic climate system, particularly cloud liquid water droplets. However, there is currently a measurement gap for cloud liquid water over sea ice. We present a method to estimate cloud liquid water over Arctic sea ice using airborne passive microwave observations from the HALO-(𝒜𝒞)3 campaign. Evaluation with other airborne sensors highlights both the limitations and potential of the retrieval. This approach is promising for future applications to satellites.

A Physics-Constrained Deep-Learning Framework based on Long-Term Remote-Sensing Data for Retrieving Vertical Distribution of PM2.5 Chemical Components

2026-04-01T11:37:12+02:00

A Physics-Constrained Deep-Learning Framework based on Long-Term Remote-Sensing Data for Retrieving Vertical Distribution of PM2.5 Chemical Components
Hongyi Li, Ting Yang, Yele Sun, and Zifa Wang
Atmos. Meas. Tech., 19, 2225–2244, https://doi.org/10.5194/amt-19-2225-2026, 2026
We develop a physics-constrained deep-learning framework to retrieve vertical profiles of particulate matter <2.5 µm chemical components from lidar measurements. Comparisons with surface, tower, and aircraft measurements validate the performance of the framework. A six-year vertical profile dataset generated for Beijing reveals that organic matter and nitrate are dominant chemical components. This work offers a new perspective on the lidar inversion of chemical component profiles.

Contribution of the 2DVD to the investigation of cloud microphysics during the MOSAiC and Cloudlab/PolarCAP campaigns

2026-04-01T11:37:12+02:00

Contribution of the 2DVD to the investigation of cloud microphysics during the MOSAiC and Cloudlab/PolarCAP campaigns
Tom Gaudek, Cristofer Jimenez, Kevin Ohneiser, Christopher Fuchs, Jan Henneberger, Johannes Bühl, Andi Klamt, Albert Ansmann, Ronny Engelmann, and Patric Seifert
Atmos. Meas. Tech., 19, 2245–2263, https://doi.org/10.5194/amt-19-2245-2026, 2026
This study introduces the maximum diameter (Dmax) of precipitation particles measured by a two-dimensional video disdrometer (2DVD) as a novel parameter. Dmax is applied in a cloud seeding study during the Cloudlab campaign and, for the first time, in a MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) case to evaluate the LIRAS (LIdar RAdar Synergy )-ice remote-sensing retrieval of in-cloud ice crystal size and number. Both quantities agreed well with the 2DVD measurements under ideal conditions, highlighting the potential of Dmax for precipitation studies.

Lidar measurement of aircraft engine particulate emissions

2026-03-30T11:37:12+02:00

Lidar measurement of aircraft engine particulate emissions
Romain Ceolato, Andrés Bedoya-Velásquez, Gerald Lemineur, Pierrick Loyers, Charles Renard, Katharina Seeliger, Louise Ganeau, Alaric Vandestoc, Ismael Ortega, Mark Johnson, and David Delhaye
Atmos. Meas. Tech., 19, 2149–2161, https://doi.org/10.5194/amt-19-2149-2026, 2026
We developed a new way to measure ultrafine particles released by aircraft engines using an aerosol lidar sensor. This method allows us to quickly check emissions from a distance, without needing to collect samples directly from the engines. Our results show that this approach works well and could help airports and regulators better monitor air quality and reduce the environmental impact of aviation.

High spatial resolution CO2 measurement using low-cost commercial sensors in Seoul megacity

2026-03-30T11:37:12+02:00

High spatial resolution CO2 measurement using low-cost commercial sensors in Seoul megacity
JaeYoung Park, Jinho Ahn, Jeongeun Kim, and Nasrin Salehnia
Atmos. Meas. Tech., 19, 2163–2173, https://doi.org/10.5194/amt-19-2163-2026, 2026
This study shows that low-cost CO2 sensors, when individually corrected using multi-point linear regression, can achieve 1–2 % accuracy. Deployed in Seoul, they revealed local pollution patterns like idling emissions at intersections and the "piston effect" in tunnels. With proper correction, these sensors enable affordable, detailed urban CO2 monitoring.

Chemical sparsity in Bayesian receptor models for aerosol source apportionment

2026-03-30T11:37:12+02:00

Chemical sparsity in Bayesian receptor models for aerosol source apportionment
Marta Via, Jure Demšar, Yufang Hao, Manousos Manousakas, Anton Rusanen, Jianhui Jiang, Stuart K. Grange, Jean-Luc Jaffrezo, Vy Ngoc Thuy Dinh, Gaëlle Uzu, Griša Močnik, and Kaspar R. Daellenbach
Atmos. Meas. Tech., 19, 2175–2195, https://doi.org/10.5194/amt-19-2175-2026, 2026
We introduce BAMF+HS (Bayesian Autocorrelated Matrix Factorisation+Horseshoe), an enhanced Bayesian receptor model for particulate matter (PM) source apportionment. By applying a regularised horseshoe prior to the chemical composition matrix, BAMF+HS enforces sparsity, filtering out irrelevant species and improving source separation. Tests on synthetic and real datasets show BAMF+HS consistently outperforms previous models in accuracy and clarity.

First nationwide analysis of riming using vertical observations from the operational German C-band radar network

2026-03-27T11:37:12+01:00

First nationwide analysis of riming using vertical observations from the operational German C-band radar network
Paul Ockenfuß, Michael Frech, Mathias Gergely, and Stefan Kneifel
Atmos. Meas. Tech., 19, 2125–2147, https://doi.org/10.5194/amt-19-2125-2026, 2026
The 17 operational German weather radars regularly point vertical for calibration. We proof that this data also contains valuable scientific information. To demonstrate this, we use it to detect the melting level in clouds and strong snowflake riming. Riming is the collision of a snowflake with liquid droplets, which can create precipitation. We analyze the frequency and temperature dependence of riming for all German weather radar sites and relate it to the local precipitation climatology.

Operational calibration of a ground-based fully polarimetric radiometer for stratospheric temperature retrievals

2026-03-26T11:37:12+01:00

Operational calibration of a ground-based fully polarimetric radiometer for stratospheric temperature retrievals
Witali Krochin, Axel Murk, Andres Luder, and Gunter Stober
Atmos. Meas. Tech., 19, 2103–2123, https://doi.org/10.5194/amt-19-2103-2026, 2026
In this manuscript a new fully polarimetric radiometer for ground-based temperature sounding, TEMPERA-C (Campaign Temperature Radiometer), is presented. The advantages of the fully polarimetric approach are discussed, and a fully polarimetric calibration method is described in detail. The final measurements and the continuous series of temperature retrievals from the high altitude research station on the Jungfraujoch are also shown in this manuscript.

Long-term cloud characterization at the AGORA ACTRIS-CCRES station using a novel classification algorithm

2026-03-26T11:37:12+01:00

Long-term cloud characterization at the AGORA ACTRIS-CCRES station using a novel classification algorithm
Matheus Tolentino, Juan Antonio Bravo-Aranda, Juan Luis Guerrero-Rascado, Francisco Navas-Guzmán, Daniel Pérez-Ramírez, Lucas Alados-Arboledas, and Maria José Granados-Muñoz
Atmos. Meas. Tech., 19, 2079–2102, https://doi.org/10.5194/amt-19-2079-2026, 2026
Clouds strongly influence weather and climate, yet long-term observations are rare in southern Europe. We analyzed five years of measurements in Granada, Spain, to study how different cloud types vary through the seasons. We developed a new method that improves cloud classification and found clear differences in height, thickness, and water content. These results provide valuable reference data to support satellite observations and climate models.

All-sky temperature and humidity retrieval from the MWRI-RM onboard the FY-3G satellite

2026-03-25T11:37:12+01:00

All-sky temperature and humidity retrieval from the MWRI-RM onboard the FY-3G satellite
Minghua Liu, Wei Han, Yunfan Yang, Haofei Sun, and Ruoying Yin
Atmos. Meas. Tech., 19, 2061–2077, https://doi.org/10.5194/amt-19-2061-2026, 2026
This research develops a machine learning approach to estimate atmospheric temperature and relative humidity profiles using satellite and weather data. The results showed that our method could accurately retrieve profiles with a high degree of precision. However, we found some limitations in very humid conditions, suggesting that further improvements to the model are needed. Our findings could help enhance the reliability of atmospheric measurements and contribute to better weather predictions.

VOLCANO3 – a Miniaturized Chemiluminescence Ozone Monitor for Drone-Based Measurements in Volcanic Plumes

2026-03-25T11:37:12+01:00

VOLCANO3 – a Miniaturized Chemiluminescence Ozone Monitor for Drone-Based Measurements in Volcanic Plumes
Maja Rüth, Nicole Bobrowski, Ellen Bräutigam, Alexander Nies, Jonas Kuhn, Thorsten Hoffmann, Niklas Karbach, Bastien Geil, Ralph Kleinschek, Stefan Schmitt, and Ulrich Platt
Atmos. Meas. Tech., 19, 2047–2059, https://doi.org/10.5194/amt-19-2047-2026, 2026
UV absorption and electrochemical O3 sensor measurement techniques suffer from interferences, especially from SO2, which is a main constituent of volcanic plumes. Only chemiluminescence (CL) O3 monitors have no known interference with SO2. However, modern CL O3 monitors are impractical because they are heavy and bulky. We developed and applied a lightweight version of a CL O3 instrument (l.5 kg, shoebox size) and present the result of those drone based CL O3 measurements.

Towards retrieving cloud top entrainment velocities from MISR cloud motion vectors

2026-03-24T11:37:12+01:00

Towards retrieving cloud top entrainment velocities from MISR cloud motion vectors
Arka Mitra and Virendra P. Ghate
Atmos. Meas. Tech., 19, 2025–2045, https://doi.org/10.5194/amt-19-2025-2026, 2026
Entrainment of dry warm air from above the cloud into the cloud layer modulates cloud properties and lifetime. Despite its importance, observations of entrainment remain elusive. Presented here is a technique to derive entrainment velocities using cloud top heights, and horizontal winds from the Multi-angle Imaging Spectro-Radiometer (MISR). The results motivate application of the technique to generate global climatology, and perform process-level and model-evaluation studies.

MAESTRO instrument operation and performance over two decades in orbit

2026-03-19T11:37:12+01:00

MAESTRO instrument operation and performance over two decades in orbit
Jiansheng Zou, C. Thomas McElroy, James R. Drummond, Kaley A. Walker, and Paul S. Jeffery
Atmos. Meas. Tech., 19, 1991–2008, https://doi.org/10.5194/amt-19-1991-2026, 2026
Two decades of operations and performance for the MAESTRO instrument are reviewed. Topics addressed include: (a) occultation measurement schemes, (b) MAESTRO's field of view (FOV) on the Sun, (c) FOV changes on the solar disk during occultations and their impact on calculated transmittances, (d) the relation between the MAESTRO and ACE-FTS FOVs, (e) verification of wavelength assignment, and how it has been affected by thermal environment changes, and (f) the determination of MAESTRO tangent heights.