Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)

<p>Lidars using vibrational and rotational Raman scattering to continuously monitor both the water vapor and temperature profiles in the low and middle troposphere offer enticing perspectives for applications in weather prediction and studies of aerosol–cloud–water vapor interactions by simult...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: J. Totems, P. Chazette, A. Baron
Formato: article
Lenguaje:EN
Publicado: Copernicus Publications 2021
Materias:
Acceso en línea:https://doaj.org/article/c0e9142d01744f44b5dd465ccc6f0aac
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
id oai:doaj.org-article:c0e9142d01744f44b5dd465ccc6f0aac
record_format dspace
spelling oai:doaj.org-article:c0e9142d01744f44b5dd465ccc6f0aac2021-12-03T15:55:08ZMitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)10.5194/amt-14-7525-20211867-13811867-8548https://doaj.org/article/c0e9142d01744f44b5dd465ccc6f0aac2021-12-01T00:00:00Zhttps://amt.copernicus.org/articles/14/7525/2021/amt-14-7525-2021.pdfhttps://doaj.org/toc/1867-1381https://doaj.org/toc/1867-8548<p>Lidars using vibrational and rotational Raman scattering to continuously monitor both the water vapor and temperature profiles in the low and middle troposphere offer enticing perspectives for applications in weather prediction and studies of aerosol–cloud–water vapor interactions by simultaneously deriving relative humidity and atmospheric optical properties. Several heavy systems exist in European laboratories, but only recently have they been downsized and ruggedized for deployment in the field. In this paper, we describe in detail the technical choices made during the design and calibration of the new Raman channels for the mobile Weather and Aerosol Lidar (WALI), going over the important sources of bias and uncertainty on the water vapor and temperature profiles stemming from the different optical elements of the instrument. For the first time, the impacts of interference filters and non-common-path differences between Raman channels, and their mitigation, in particular are investigated, using horizontal shots in a homogeneous atmosphere. For temperature, the magnitude of the highlighted biases can be much larger than the targeted absolute accuracy of 1 <span class="inline-formula"><sup>∘</sup>C</span> defined by the WMO (up to 6 <span class="inline-formula"><sup>∘</sup>C</span> bias below 300 <span class="inline-formula">m</span> range). Measurement errors are quantified using simulations and a number of radiosoundings launched close to the laboratory. After de-biasing, the remaining mean differences are below 0.1 <span class="inline-formula">g kg<sup>−1</sup></span> on water vapor and 1 <span class="inline-formula"><sup>∘</sup>C</span> on temperature, and rms differences are consistent with the expected error from lidar noise, calibration uncertainty, and horizontal inhomogeneities of the atmosphere between the lidar and radiosondes.</p>J. TotemsP. ChazetteA. BaronCopernicus PublicationsarticleEnvironmental engineeringTA170-171Earthwork. FoundationsTA715-787ENAtmospheric Measurement Techniques, Vol 14, Pp 7525-7544 (2021)
institution DOAJ
collection DOAJ
language EN
topic Environmental engineering
TA170-171
Earthwork. Foundations
TA715-787
spellingShingle Environmental engineering
TA170-171
Earthwork. Foundations
TA715-787
J. Totems
P. Chazette
A. Baron
Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
description <p>Lidars using vibrational and rotational Raman scattering to continuously monitor both the water vapor and temperature profiles in the low and middle troposphere offer enticing perspectives for applications in weather prediction and studies of aerosol–cloud–water vapor interactions by simultaneously deriving relative humidity and atmospheric optical properties. Several heavy systems exist in European laboratories, but only recently have they been downsized and ruggedized for deployment in the field. In this paper, we describe in detail the technical choices made during the design and calibration of the new Raman channels for the mobile Weather and Aerosol Lidar (WALI), going over the important sources of bias and uncertainty on the water vapor and temperature profiles stemming from the different optical elements of the instrument. For the first time, the impacts of interference filters and non-common-path differences between Raman channels, and their mitigation, in particular are investigated, using horizontal shots in a homogeneous atmosphere. For temperature, the magnitude of the highlighted biases can be much larger than the targeted absolute accuracy of 1 <span class="inline-formula"><sup>∘</sup>C</span> defined by the WMO (up to 6 <span class="inline-formula"><sup>∘</sup>C</span> bias below 300 <span class="inline-formula">m</span> range). Measurement errors are quantified using simulations and a number of radiosoundings launched close to the laboratory. After de-biasing, the remaining mean differences are below 0.1 <span class="inline-formula">g kg<sup>−1</sup></span> on water vapor and 1 <span class="inline-formula"><sup>∘</sup>C</span> on temperature, and rms differences are consistent with the expected error from lidar noise, calibration uncertainty, and horizontal inhomogeneities of the atmosphere between the lidar and radiosondes.</p>
format article
author J. Totems
P. Chazette
A. Baron
author_facet J. Totems
P. Chazette
A. Baron
author_sort J. Totems
title Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
title_short Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
title_full Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
title_fullStr Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
title_full_unstemmed Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
title_sort mitigation of bias sources for atmospheric temperature and humidity in the mobile raman weather and aerosol lidar (wali)
publisher Copernicus Publications
publishDate 2021
url https://doaj.org/article/c0e9142d01744f44b5dd465ccc6f0aac
work_keys_str_mv AT jtotems mitigationofbiassourcesforatmospherictemperatureandhumidityinthemobileramanweatherandaerosollidarwali
AT pchazette mitigationofbiassourcesforatmospherictemperatureandhumidityinthemobileramanweatherandaerosollidarwali
AT abaron mitigationofbiassourcesforatmospherictemperatureandhumidityinthemobileramanweatherandaerosollidarwali
_version_ 1718373171549175808