From prototypical regimes to observed complex dynamics and CO ₂ transport in the Amazonian nocturnal boundary layer
- 1Wageningen University & Research (Wageningen, Netherlands)
Abstract
We investigated the characteristics of the nocturnal boundary layer (NBL) above and within the Amazon rainforest canopy during the 2022 dry season. We analysed observed NBL dynamics and CO ₂ transport from the perspective of the prototypical NBL represented in weather and climate models. To this end, using the CloudRoots-Amazon22 dataset, we characterised the main NBL features and governing processes. We identified NBL height using five methods based on thermal stratification, wind, and turbulent criteria, finding a distinct stable layer above the canopy with an average height between 142–164 m. To examine the drivers of the dynamic NBL evolution, we classified the data into weakly and strongly stable regimes, determined by the interplay between stabilising longwave radiative cooling and destabilising mechanical wind shear. Budget equations for turbulent kinetic energy (TKE), heat, and CO ₂ allowed us to quantify the relative contributions of these drivers to transport across the canopy-atmosphere interface. In the weakly stable regime, increased TKE at the canopy top promoted mixing between the within- and above-canopy layers. Conversely, TKE was nearly absent in the strongly stable regime, decoupling the two layers. This decoupling favoured strong thermal stratification above the canopy and well-mixed conditions within the canopy. Our results show that only about 6 % of observed profiles conform to prototypical NBL regimes, emphasising the need to revisit parameterisations to explicitly account for canopy-induced effects and intermittent turbulence. Our observational analysis provides a critical benchmark for improving the representation of NBL dynamics and CO ₂ transport in models.
Versions
Related
- Origin and pathways of the mineral dust transport to two Spanish EARLINET sites: Effect on the observed columnar and range-resolved dust optical properties
- Transcontinental transport of a massive SO 2 plume from the Tehran refinery explosion in March 2026 observed from space
- Direct generation of a prototypical n-pentyl peroxy radical reveals how mixedfate chemical regimes shape product distributions
- Variability of suspended sediment transport dynamics between seasons and flow pathways in a small agricultural catchment
- Amazonian rainforest bioaerosol influenced by African dust intrusion
BibTeX
@article{huitema2026from,
title = {{From prototypical regimes to observed complex dynamics and CO ₂ transport in the Amazonian nocturnal boundary layer}},
author = {Anna C. Huitema and Vincent S. de Feiter and Raquel González-Armas and Oscar K. Hartogensis and Hella van Asperen and Cleo Q. Dias-Júnior and Jordi Vilà-Guerau de Arellano},
journal = {Atmospheric Chemistry and Physics},
year = {2026},
month = oct,
doi = {10.5194/acp-26-14725-2026},
url = {https://acp.copernicus.org/articles/26/14725/2026/},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - From prototypical regimes to observed complex dynamics and CO ₂ transport in the Amazonian nocturnal boundary layer
AU - Anna C. Huitema
AU - Vincent S. de Feiter
AU - Raquel González-Armas
AU - Oscar K. Hartogensis
AU - Hella van Asperen
AU - Cleo Q. Dias-Júnior
AU - Jordi Vilà-Guerau de Arellano
PY - 2026
DA - 2026/10/20
JO - Atmospheric Chemistry and Physics
DO - 10.5194/acp-26-14725-2026
UR - https://acp.copernicus.org/articles/26/14725/2026/
AB - We investigated the characteristics of the nocturnal boundary layer (NBL) above and within the Amazon rainforest canopy during the 2022 dry season. We analysed observed NBL dynamics and CO ₂ transport from the perspective of the prototypical NBL represented in weather and climate models. To this end, using the CloudRoots-Amazon22 dataset, we characterised the main NBL features and governing processes. We identified NBL height using five methods based on thermal stratification, wind, and turbulent criteria, finding a distinct stable layer above the canopy with an average height between 142–164 m. To examine the drivers of the dynamic NBL evolution, we classified the data into weakly and strongly stable regimes, determined by the interplay between stabilising longwave radiative cooling and destabilising mechanical wind shear. Budget equations for turbulent kinetic energy (TKE), heat, and CO ₂ allowed us to quantify the relative contributions of these drivers to transport across the canopy-atmosphere interface. In the weakly stable regime, increased TKE at the canopy top promoted mixing between the within- and above-canopy layers. Conversely, TKE was nearly absent in the strongly stable regime, decoupling the two layers. This decoupling favoured strong thermal stratification above the canopy and well-mixed conditions within the canopy. Our results show that only about 6 % of observed profiles conform to prototypical NBL regimes, emphasising the need to revisit parameterisations to explicitly account for canopy-induced effects and intermittent turbulence. Our observational analysis provides a critical benchmark for improving the representation of NBL dynamics and CO ₂ transport in models.
SN - 1680-7324
ER -