Articles | Volume 18, issue 1
https://doi.org/10.5194/amt-18-305-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-18-305-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Jan 2025
Research article |
| 16 Jan 2025
| 16 Jan 2025
Calibration of optical particle spectrometers using mounted fibres
Jessica Girdwood
CORRESPONDING AUTHOR
Centre for Atmospheric and Climate Physics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB, UK
now at: School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
now at: National Centre for Atmospheric Science, School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
Harry Ballington
Centre for Atmospheric and Climate Physics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB, UK
Chris Stopford
Centre for Atmospheric and Climate Physics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB, UK
Rob Lewis
Centre for Atmospheric and Climate Physics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB, UK
Evelyn Hesse
Centre for Atmospheric and Climate Physics, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB, UK
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Clouds play a key role in weather and climate. Pure liquid water droplets are liquid until about -35 °C without the presence of a small subset of aerosols, ice-nucleating particles (INPs). These INPs lead to primary ice formation and therefore impact the phase of clouds. The dataset described herein provides INP concentration measurements at two altitudes. Connecting this data to synoptic conditions and ambient data might provide a better understanding of INPs in Finnish Lapland.
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Mineral dust particles emitted from dry soils are of various sizes, yet the abundance of very large particles is not well understood. Here we measured the dust size distribution from fine to giant particles at an emission source during a field campaign in Jordan (J-WADI) using multiple instruments. Our findings show that large particles make up a significant part of the total dust mass. This knowledge is essential to improve climate models and to predict dust impacts on climate and environment.
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Clouds play a key role in weather and climate. Pure liquid water droplets are liquid until about -35 °C without the presence of a small subset of aerosols, ice-nucleating particles (INPs). These INPs lead to primary ice formation and therefore impact the phase of clouds. The dataset described herein provides INP concentration measurements at two altitudes. Connecting this data to synoptic conditions and ambient data might provide a better understanding of INPs in Finnish Lapland.
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UAVs have great potential to be used for airborne measurements of cloud and aerosol properties, which are of particular importance due to the largely uncharacterised nature of such phenomena. However, since UAVs are a new tool in atmospheric physics expensive platform validation and characterisation of UAV-instrument combinations needs to be performed. This paper presents an evaluation of a fixed-wing UAV in combination with an instrument that measures cloud droplet diameter.
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We present the design and validation of an unmanned aerial vehicle (UAV) equipped with a bespoke optical particle counter (OPC). This is used to monitor atmospheric particles, which have significant effects on our weather and climate. These effects are hard to characterise properly, partly because they occur in regions that are not commonly accessible to traditional instrumentation. Our new platform gives us the capability to access these regions.
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Short summary
Optical particle spectrometers (OPSs) are a class of instruments (commonly used for measurement of particle size distributions) that require calibration. Conventionally, this is performed using a known aerosol source, which has reliability issues. In this paper, we present a technique for OPS calibration which involves placing objects in the instrument that generate a known response. This fibre calibration method was more reliable than a conventional calibration.
Optical particle spectrometers (OPSs) are a class of instruments (commonly used for measurement...
