Data

Holographic imaging of snow particles at Davis Station, Summer 2018-2019

Australian Antarctic Division
Chambers, T.E. and Hamilton, M. ; HAMILTON, MURRAY ; CHAMBERS, THOMAS EDWARD
Viewed: [[ro.stat.viewed]] Cited: [[ro.stat.cited]] Accessed: [[ro.stat.accessed]]
ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rfr_id=info%3Asid%2FANDS&rft_id=http://data.aad.gov.au/metadata/AAS_4308_Davis_Snow_Holograms&rft.title=Holographic imaging of snow particles at Davis Station, Summer 2018-2019&rft.identifier=http://data.aad.gov.au/metadata/AAS_4308_Davis_Snow_Holograms&rft.publisher=Australian Antarctic Data Centre&rft.description=Holographic imaging of snow particles at Davis Station, Summer 2018-2019 Thomas Chambers and Murray Hamilton, University of AdelaideUniversity of Adelaide instruments (Holographic Microscope and Polarsonde) were deployed at Davis Station, Antarctica from November 2018 to October 2019. These were part of a wider campaign to study clouds and precipitation over the Southern Ocean (and its boundaries).Other precipitation instruments include: MASC, POLAR LIDAR, BASTA, RMAN, MXPol, ceilometer, MRR, Parsivel disdrometer, Pluviometer (associated with project AAS 4292), plus Snow Drift Tower, radiometers, MET observations.This dataset includes the following:• A version of this document with pictures to give added context• Raw holograms (in JPEG format) sampled at approximately 1-second intervals during snowfall events on Jan 6th and Jan 8th 2019• Raw holograms (in raw format) sampled at approximately 10-second intervals during a snowfall event on Nov 24th 2018• Some time-stamped particle images from the preliminary manual analysis of the Jan 8th event. • Example Matlab scripts showing how to reconstruct images from the holograms, and how to read a hologram file in raw format.The dates of the included data have been selected to correspond with precipitation events (falling or drifting snow), as detected by one or more of the associated instruments, primarily the pluviometer (a snowfall gauge analogous to a rain gauge), the POLAR lidar and the snow particle counter. This selection was made to keep the amount of uploaded data reasonable.The timestamps for the holograms are built into the data filenames generated by the camera. The format is “Qtcam-yy_mm_dd-hh_MM_ss” .The camera is a See3CAM_CU51 from e-con Systems India Pvt Ltd, operated in global shutter mode to handle the 150ns laser pulse width. Its sensor has 2592 x 1944 pixels. One of the Matlab scripts shows how to read files in the camera’s raw format, which is not like other camera raw formats such as *.dng, *.pef etc.Holographic Microscope Resolution• Diffraction limited longitudinal resolution significantly poorer than transverse resolution• Resolution is measured experimentally due to hard to constrain contributions from the laser spatial + temporal coherence, dynamic range of camera, camera noise etc.• Can effectively resolve particles with sizes ranging from ~3 microns up to 3mm within a sampling volume of ~1 cubic centimetre Progress Code: completedStatement: Stray sunlight from certain angles during clear or partly cloudy conditions can cause saturation of the camera sensor used to obtain the holograms. The holograms have been selected for days during which other instruments recorded snow particles, which mitigates this problem because this corresponds mostly to overcast weather. Saturation is fairly obvious when it occurs.&rft.creator=Chambers, T.E. and Hamilton, M. &rft.creator=HAMILTON, MURRAY &rft.creator=CHAMBERS, THOMAS EDWARD &rft.date=2023&rft.coverage=westlimit=74.125; southlimit=-69.73481; eastlimit=81.96875; northlimit=-67.32166&rft.coverage=westlimit=74.125; southlimit=-69.73481; eastlimit=81.96875; northlimit=-67.32166&rft_rights=These data are publicly available for download from the provided URL.&rft_rights=Attribution 4.0 International (CC BY 4.0) https://creativecommons.org/licenses/by/4.0/legalcode&rft_rights=This data set conforms to the CCBY Attribution License (http://creativecommons.org/licenses/by/4.0/). Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=AAS_4308_Davis_Snow_Holograms when using these data.&rft_rights=This metadata record is publicly available.&rft_subject=climatologyMeteorologyAtmosphere&rft_subject=EARTH SCIENCE > ATMOSPHERE > CLOUDS > CLOUD MICROPHYSICS > PARTICLE SIZE DISTRIBUTION&rft_subject=EARTH SCIENCE > ATMOSPHERE > PRECIPITATION > SOLID PRECIPITATION > SNOW&rft_subject=HOLOGRAPHIC MICROSCOPE&rft_subject=PLUVIOMETER&rft_subject=MICROSCOPES > MICROSCOPES&rft_subject=DISDROMETERS&rft_subject=FIXED OBSERVATION STATIONS > FIXED OBSERVATION STATIONS&rft_subject=AMD/AU&rft_subject=AMD&rft_subject=CEOS&rft_subject=GEOGRAPHIC REGION > POLAR&rft_subject=CONTINENT > ANTARCTICA > DAVIS STATION&rft.type=dataset&rft.language=English Access the data

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Attribution 4.0 International (CC BY 4.0)
https://creativecommons.org/licenses/by/4.0/legalcode

These data are publicly available for download from the provided URL.

This data set conforms to the CCBY Attribution License (http://creativecommons.org/licenses/by/4.0/).

Please follow instructions listed in the citation reference provided at http://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=AAS_4308_Davis_Snow_Holograms when using these data.

This metadata record is publicly available.

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Full description

Holographic imaging of snow particles at Davis Station, Summer 2018-2019 Thomas Chambers and Murray Hamilton, University of Adelaide

University of Adelaide instruments (Holographic Microscope and Polarsonde) were deployed at Davis Station, Antarctica from November 2018 to October 2019. These were part of a wider campaign to study clouds and precipitation over the Southern Ocean (and its boundaries).

Other precipitation instruments include: MASC, POLAR LIDAR, BASTA, RMAN, MXPol, ceilometer, MRR, Parsivel disdrometer, Pluviometer (associated with project AAS 4292), plus Snow Drift Tower, radiometers, MET observations.

This dataset includes the following:
• A version of this document with pictures to give added context
• Raw holograms (in JPEG format) sampled at approximately 1-second intervals during snowfall events on Jan 6th and Jan 8th 2019
• Raw holograms (in raw format) sampled at approximately 10-second intervals during a snowfall event on Nov 24th 2018
• Some time-stamped particle images from the preliminary manual analysis of the Jan 8th event.
• Example Matlab scripts showing how to reconstruct images from the holograms, and how to read a hologram file in raw format.

The dates of the included data have been selected to correspond with precipitation events (falling or drifting snow), as detected by one or more of the associated instruments, primarily the pluviometer (a snowfall gauge analogous to a rain gauge), the POLAR lidar and the snow particle counter. This selection was made to keep the amount of uploaded data reasonable.

The timestamps for the holograms are built into the data filenames generated by the camera. The format is “Qtcam-yy_mm_dd-hh_MM_ss” .

The camera is a See3CAM_CU51 from e-con Systems India Pvt Ltd, operated in global shutter mode to handle the 150ns laser pulse width. Its sensor has 2592 x 1944 pixels. One of the Matlab scripts shows how to read files in the camera’s raw format, which is not like other camera raw formats such as *.dng, *.pef etc.

Holographic Microscope Resolution
• Diffraction limited longitudinal resolution significantly poorer than transverse resolution
• Resolution is measured experimentally due to hard to constrain contributions from the laser spatial + temporal coherence, dynamic range of camera, camera noise etc.
• Can effectively resolve particles with sizes ranging from ~3 microns up to 3mm within a sampling volume of ~1 cubic centimetre

Lineage

Progress Code: completed
Statement: Stray sunlight from certain angles during clear or partly cloudy conditions can cause saturation of the camera sensor used to obtain the holograms. The holograms have been selected for days during which other instruments recorded snow particles, which mitigates this problem because this corresponds mostly to overcast weather. Saturation is fairly obvious when it occurs.

Data time period: 2018-11-23 to 2019-01-30

This dataset is part of a larger collection

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81.96875,-67.32166 81.96875,-69.73481 74.125,-69.73481 74.125,-67.32166 81.96875,-67.32166

78.046875,-68.528235

text: westlimit=74.125; southlimit=-69.73481; eastlimit=81.96875; northlimit=-67.32166

Other Information
Citation reference for this metadata record and dataset. (GET DATA > DIRECT DOWNLOAD)

uri : https://data.aad.gov.au/eds/5696/download

Public information for AAS project AAS_4308 (PROJECT HOME PAGE)

uri : https://projects.aad.gov.au/report_project_public.cfm?project_no=AAS_4308

Citation reference for this metadata record and dataset. (VIEW RELATED INFORMATION)

uri : https://data.aad.gov.au/aadc/metadata/citation.cfm?entry_id=AAS_4308_Davis_Snow_Holograms

Identifiers
  • global : AAS_4308_Davis_Snow_Holograms