The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape

<p>We study the diurnal variability in the atmospheric boundary layer (ABL) across spatial scales (between <span class="inline-formula">∼100</span> m and <span class="inline-formula">∼10</span> km) of irrigation-driven surface heterogeneity in the se...

Full description

Saved in:
Bibliographic Details
Main Authors: M. R. Mangan, J. Vilà-Guerau de Arellano, B. J. H. van Stratum, M. Lothon, G. Canut-Rocafort, O. K. Hartogensis
Format: Article
Language:English
Published: Copernicus Publications 2025-08-01
Series:Atmospheric Chemistry and Physics
Online Access:https://acp.copernicus.org/articles/25/8959/2025/acp-25-8959-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849390307862380544
author M. R. Mangan
M. R. Mangan
J. Vilà-Guerau de Arellano
B. J. H. van Stratum
M. Lothon
G. Canut-Rocafort
O. K. Hartogensis
author_facet M. R. Mangan
M. R. Mangan
J. Vilà-Guerau de Arellano
B. J. H. van Stratum
M. Lothon
G. Canut-Rocafort
O. K. Hartogensis
author_sort M. R. Mangan
collection DOAJ
description <p>We study the diurnal variability in the atmospheric boundary layer (ABL) across spatial scales (between <span class="inline-formula">∼100</span> m and <span class="inline-formula">∼10</span> km) of irrigation-driven surface heterogeneity in the semi-arid landscape of the 2021 Land surface Interactions with the Atmosphere over the Iberian Semi-arid Environment (LIAISE) experiment on the northeastern Iberian Peninsula. We combine observational analysis with explicit simulation of the ABL using observationally driven large-eddy simulation (LES) to better understand the physical mechanisms controlling ABL dynamics in heterogeneous regions. Our choice of spatial scales represents current and future single grid cells of global models, demonstrating how the sources and magnitude of subgrid-scale heterogeneity vary with model resolution.</p> <p>There is an observed positive buoyancy flux over the irrigated fields driven primarily by moisture fluxes, whereas, over the non-irrigated fields, there is a classical buoyancy profile driven by the surface sensible heat flux. The surface heterogeneity is felt most strongly near the surface; however, at approximately 1000 m above the surface, there appears to be a blending zone of mean scalars (i.e., potential temperature and specific humidity), indicating that the heterogeneity mixes into a new mean state of the atmosphere. There is a stable internal boundary layer (IBL; as defined as the first stable layer in individual radiosonde potential temperature profiles) up to approximately 500 m over the irrigated area. Taking advantage of the spatiotemporal extent of LES results, we perform spectral analyses to find that the ABL height had an integral length scale of <span class="inline-formula">∼800</span> m matching that of the imposed surface fluxes. Between the irrigated and non-irrigated areas, there is an adjustment of the ABL as it crosses the boundary up to 500 m upwind of the boundary. We observe a variable-dependent blending zone between scales in the middle of the ABL, but it is limited by the entrainment zone effectively introducing another source of heterogeneity driven by upper-atmosphere conditions.</p>
format Article
id doaj-art-18a48b6be65a48028a08f28a9f867f2b
institution Kabale University
issn 1680-7316
1680-7324
language English
publishDate 2025-08-01
publisher Copernicus Publications
record_format Article
series Atmospheric Chemistry and Physics
spelling doaj-art-18a48b6be65a48028a08f28a9f867f2b2025-08-20T03:41:43ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242025-08-01258959898110.5194/acp-25-8959-2025The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscapeM. R. Mangan0M. R. Mangan1J. Vilà-Guerau de Arellano2B. J. H. van Stratum3M. Lothon4G. Canut-Rocafort5O. K. Hartogensis6Meteorology and Air Quality, Wageningen University & Research, Droevendaalsesteeg 4, 6708 PB, Wageningen, the NetherlandsInvited contribution by Mary Rose Mangan, recipient of the EGU Atmospheric Sciences Outstanding Student and PhD candidate Presentation Award 2022.Meteorology and Air Quality, Wageningen University & Research, Droevendaalsesteeg 4, 6708 PB, Wageningen, the NetherlandsMeteorology and Air Quality, Wageningen University & Research, Droevendaalsesteeg 4, 6708 PB, Wageningen, the NetherlandsLaboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, 14 avenue Edouard Belin 31400, Toulouse, FranceCentre National de Recherches Météorologiques (CNRM)/Météo-France, 42 ave. G. Coriolis, 31057, Toulouse, FranceMeteorology and Air Quality, Wageningen University & Research, Droevendaalsesteeg 4, 6708 PB, Wageningen, the Netherlands<p>We study the diurnal variability in the atmospheric boundary layer (ABL) across spatial scales (between <span class="inline-formula">∼100</span> m and <span class="inline-formula">∼10</span> km) of irrigation-driven surface heterogeneity in the semi-arid landscape of the 2021 Land surface Interactions with the Atmosphere over the Iberian Semi-arid Environment (LIAISE) experiment on the northeastern Iberian Peninsula. We combine observational analysis with explicit simulation of the ABL using observationally driven large-eddy simulation (LES) to better understand the physical mechanisms controlling ABL dynamics in heterogeneous regions. Our choice of spatial scales represents current and future single grid cells of global models, demonstrating how the sources and magnitude of subgrid-scale heterogeneity vary with model resolution.</p> <p>There is an observed positive buoyancy flux over the irrigated fields driven primarily by moisture fluxes, whereas, over the non-irrigated fields, there is a classical buoyancy profile driven by the surface sensible heat flux. The surface heterogeneity is felt most strongly near the surface; however, at approximately 1000 m above the surface, there appears to be a blending zone of mean scalars (i.e., potential temperature and specific humidity), indicating that the heterogeneity mixes into a new mean state of the atmosphere. There is a stable internal boundary layer (IBL; as defined as the first stable layer in individual radiosonde potential temperature profiles) up to approximately 500 m over the irrigated area. Taking advantage of the spatiotemporal extent of LES results, we perform spectral analyses to find that the ABL height had an integral length scale of <span class="inline-formula">∼800</span> m matching that of the imposed surface fluxes. Between the irrigated and non-irrigated areas, there is an adjustment of the ABL as it crosses the boundary up to 500 m upwind of the boundary. We observe a variable-dependent blending zone between scales in the middle of the ABL, but it is limited by the entrainment zone effectively introducing another source of heterogeneity driven by upper-atmosphere conditions.</p>https://acp.copernicus.org/articles/25/8959/2025/acp-25-8959-2025.pdf
spellingShingle M. R. Mangan
M. R. Mangan
J. Vilà-Guerau de Arellano
B. J. H. van Stratum
M. Lothon
G. Canut-Rocafort
O. K. Hartogensis
The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
Atmospheric Chemistry and Physics
title The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
title_full The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
title_fullStr The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
title_full_unstemmed The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
title_short The spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
title_sort spatiotemporal evolution of atmospheric boundary layers over a thermally heterogeneous landscape
url https://acp.copernicus.org/articles/25/8959/2025/acp-25-8959-2025.pdf
work_keys_str_mv AT mrmangan thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT mrmangan thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT jvilagueraudearellano thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT bjhvanstratum thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT mlothon thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT gcanutrocafort thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT okhartogensis thespatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT mrmangan spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT mrmangan spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT jvilagueraudearellano spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT bjhvanstratum spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT mlothon spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT gcanutrocafort spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape
AT okhartogensis spatiotemporalevolutionofatmosphericboundarylayersoverathermallyheterogeneouslandscape