Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model
Large explosive eruptions can result in the formation of an umbrella cloud which rapidly expands, spreading ash out radially from the volcano. The lateral spread by the intrusive gravity current dominates the transport of the ash cloud. Hence, to accurately forecast the transport of ash from large e...
Published in: | Atmosphere |
---|---|
Main Authors: | , , , , |
Format: | Text |
Language: | English |
Published: |
Multidisciplinary Digital Publishing Institute
2020
|
Subjects: | |
Online Access: | https://doi.org/10.3390/atmos11020200 |
id |
ftmdpi:oai:mdpi.com:/2073-4433/11/2/200/ |
---|---|
record_format |
openpolar |
spelling |
ftmdpi:oai:mdpi.com:/2073-4433/11/2/200/ 2023-08-20T04:06:21+02:00 Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model Helen N. Webster Benjamin J. Devenish Larry G. Mastin David J. Thomson Alexa R. Van Eaton agris 2020-02-13 application/pdf https://doi.org/10.3390/atmos11020200 EN eng Multidisciplinary Digital Publishing Institute Air Quality https://dx.doi.org/10.3390/atmos11020200 https://creativecommons.org/licenses/by/4.0/ Atmosphere; Volume 11; Issue 2; Pages: 200 umbrella cloud volcanic ash transport and dispersion model lateral spread satellite observations operational forecasting Text 2020 ftmdpi https://doi.org/10.3390/atmos11020200 2023-07-31T23:06:47Z Large explosive eruptions can result in the formation of an umbrella cloud which rapidly expands, spreading ash out radially from the volcano. The lateral spread by the intrusive gravity current dominates the transport of the ash cloud. Hence, to accurately forecast the transport of ash from large eruptions, lateral spread of umbrella clouds needs to be represented within volcanic ash transport and dispersion models. Here, we describe an umbrella cloud parameterisation which has been implemented into an operational Lagrangian model and consider how it may be used during an eruption when information concerning the eruption is limited and model runtime is key. We examine different relations for the volume flow rate into the umbrella, and the rate of spreading within the cloud. The scheme is validated against historic eruptions of differing scales (Pinatubo 1991, Kelud 2014, Calbuco 2015 and Eyjafjallajökull 2010) by comparing model predictions with satellite observations. Reasonable predictions of umbrella cloud spread are achieved using an estimated volume flow rate from the empirical equation by Bursik et al. and the observed eruption height. We show how model predictions can be refined during an ongoing eruption as further information and observations become available. Text Eyjafjallajökull MDPI Open Access Publishing Bursik ENVELOPE(-84.383,-84.383,-79.717,-79.717) Atmosphere 11 2 200 |
institution |
Open Polar |
collection |
MDPI Open Access Publishing |
op_collection_id |
ftmdpi |
language |
English |
topic |
umbrella cloud volcanic ash transport and dispersion model lateral spread satellite observations operational forecasting |
spellingShingle |
umbrella cloud volcanic ash transport and dispersion model lateral spread satellite observations operational forecasting Helen N. Webster Benjamin J. Devenish Larry G. Mastin David J. Thomson Alexa R. Van Eaton Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
topic_facet |
umbrella cloud volcanic ash transport and dispersion model lateral spread satellite observations operational forecasting |
description |
Large explosive eruptions can result in the formation of an umbrella cloud which rapidly expands, spreading ash out radially from the volcano. The lateral spread by the intrusive gravity current dominates the transport of the ash cloud. Hence, to accurately forecast the transport of ash from large eruptions, lateral spread of umbrella clouds needs to be represented within volcanic ash transport and dispersion models. Here, we describe an umbrella cloud parameterisation which has been implemented into an operational Lagrangian model and consider how it may be used during an eruption when information concerning the eruption is limited and model runtime is key. We examine different relations for the volume flow rate into the umbrella, and the rate of spreading within the cloud. The scheme is validated against historic eruptions of differing scales (Pinatubo 1991, Kelud 2014, Calbuco 2015 and Eyjafjallajökull 2010) by comparing model predictions with satellite observations. Reasonable predictions of umbrella cloud spread are achieved using an estimated volume flow rate from the empirical equation by Bursik et al. and the observed eruption height. We show how model predictions can be refined during an ongoing eruption as further information and observations become available. |
format |
Text |
author |
Helen N. Webster Benjamin J. Devenish Larry G. Mastin David J. Thomson Alexa R. Van Eaton |
author_facet |
Helen N. Webster Benjamin J. Devenish Larry G. Mastin David J. Thomson Alexa R. Van Eaton |
author_sort |
Helen N. Webster |
title |
Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
title_short |
Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
title_full |
Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
title_fullStr |
Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
title_full_unstemmed |
Operational Modelling of Umbrella Cloud Growth in a Lagrangian Volcanic Ash Transport and Dispersion Model |
title_sort |
operational modelling of umbrella cloud growth in a lagrangian volcanic ash transport and dispersion model |
publisher |
Multidisciplinary Digital Publishing Institute |
publishDate |
2020 |
url |
https://doi.org/10.3390/atmos11020200 |
op_coverage |
agris |
long_lat |
ENVELOPE(-84.383,-84.383,-79.717,-79.717) |
geographic |
Bursik |
geographic_facet |
Bursik |
genre |
Eyjafjallajökull |
genre_facet |
Eyjafjallajökull |
op_source |
Atmosphere; Volume 11; Issue 2; Pages: 200 |
op_relation |
Air Quality https://dx.doi.org/10.3390/atmos11020200 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/atmos11020200 |
container_title |
Atmosphere |
container_volume |
11 |
container_issue |
2 |
container_start_page |
200 |
_version_ |
1774717371674525696 |