Overestimated Fog-Top Entrainment in WRF Simulation Leading to Unrealistic Dissipation of Sea Fog: A Case Study DOI Creative Commons
Li Zhang, Hao Shi, Shanhong Gao

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(10), P. 1656 - 1656

Published: May 7, 2024

Entrainment at the top of planetary boundary layer (PBL) is significant importance because it controls upward growth PBL height. An option called ysu_topdown_pblmix, which provides a parameterization fog-top entrainment, has been proposed for valley fog modeling and introduced into YSU (Yonsei University) scheme in Weather Research Forecasting (WRF) model. However, enabling this simulations sea over Yellow Sea typically results unrealistic dissipation near bottom even within entire layer. In study, we theoretically examine composition then argue that one term might be redundant sea-fog modeling. The variables are employed to determine basic entrainment dry PBL, already parameterized by surface original scheme. This likely leads an overestimation rate, so refer as redundant. To explore connection between dissipation, widespread episode case study based on WRF simulation clearly attribute extra rate induces. Fog-top unexpectedly overestimated due resulting significantly drier warmer bias interior fog. When develops reaches temperature lower than surface, functions warming source heat jointly with downward flux brought leading initially occur gradually expand upwards. We suggest straightforward method modify ysu_topdown_pblmix eliminates term. improvement effect was supported sensitivity tests. more cases required validate modification method.

Language: Английский

Ground visibility prediction using tree-based and random-forest machine learning algorithm: Comparative study based on atmospheric pollution and atmospheric boundary layer data DOI

Fuzeng Wang,

Ruolan Liu, Hao Yan

et al.

Atmospheric Pollution Research, Journal Year: 2024, Volume and Issue: 15(11), P. 102270 - 102270

Published: July 29, 2024

Language: Английский

Citations

6
Impact of Improved Surface Flux Parameterization on Simulation of Radiation Fog Formation in the Yangtze River Delta, China DOI

Naifu Shao,

Chunsong Lu, Yubin Li

et al.

Journal of Geophysical Research Atmospheres, Journal Year: 2025, Volume and Issue: 130(9)

Published: April 30, 2025

Abstract Meteorological conditions within the boundary layer play significant roles in radiation fog formation, which typically occur under stable conditions. The stratification surface are represented by stability parameter ( ζ ), calculated as ratio of reference height z to Monin‐Obukhov length L (i.e., = / ). Current schemes exhibit uncertainties strong > 1). Grachev2007 scheme for 1 and Li2014 Li2015 calculating implemented into Weather Research Forecasting model coupled with Chemistry (WRF‐Chem). Two successive events Yangtze River Delta simulated compare improved default scheme. Both high‐pressure characterized clear sky light wind during nighttime. results indicate that dominate before improves threat scores formation. Regarding flux, due reduced thermal resistance parameterization, increased heat exchange enhances cooling from sensible flux 1, is conducive turbulent mixing, dynamic drag reduces speed 1. This weakens contribution shear kinetic energy, ultimately promoting findings this paper applicable simulations other regions, such plain areas covered grassland, cropland, or vegetation, providing support improving simulation.

Language: Английский

Citations

0
Numeral simulation of impacts of sea land breeze on the formation and dissipation of the Bohai Sea fog DOI
Lihong Meng, Lili Liu, Meng Tian

et al.

Atmospheric Research, Journal Year: 2025, Volume and Issue: unknown, P. 108190 - 108190

Published: May 1, 2025

Language: Английский

Citations

0
High‐Resolution Simulation of Dense Fog in Tianjin City: Effect of Horizontal Resolutions From Mesoscale to Large Eddy Scale DOI Creative Commons
Tian Meng, Shun Li, Wei Wei

et al.

Meteorological Applications, Journal Year: 2025, Volume and Issue: 32(3)

Published: May 1, 2025

ABSTRACT Fog is one of the most severe weather phenomena affecting safety land, sea, and air transportation, with significant impacts on national economies. This study investigates a dense fog event visibility less than 50 m that occurred in Tianjin city from December 19 to 20, 2016. Using large‐eddy simulation (LES) capability Weather Research Forecasting (WRF) model, quadruple one‐way nesting approach was applied downscale horizontal resolution 5 1 km at mesoscale 200 40 scale, providing high‐resolution simulations this event. Combined Himawari‐8 satellite retrievals, surface meteorological data, 255 tower droplet spectral compares performance different grid resolutions during discusses interaction between cloud microphysics parameterization fine‐scale turbulence simulations. The results reveal: With increasing resolution, model becomes more sensitive fluctuations variables within layer, resulting pronounced diurnal variation tendency for dissipate readily. At m, WRF‐LES yields smallest errors boundary layer temperature humidity profiles, owing its ability capture structure buoyancy oscillations top. In addition, onset dissipation closely linked coordination microphysical parameterizations, which are related autoconversion process. Among tested schemes, Purdue Lin scheme shows best agreement observed results. There mutual interactions together determine accuracy

Language: Английский

Citations

0
Overestimated Fog-Top Entrainment in WRF Simulation Leading to Unrealistic Dissipation of Sea Fog: A Case Study DOI Creative Commons
Li Zhang, Hao Shi, Shanhong Gao

et al.

Remote Sensing, Journal Year: 2024, Volume and Issue: 16(10), P. 1656 - 1656

Published: May 7, 2024

Entrainment at the top of planetary boundary layer (PBL) is significant importance because it controls upward growth PBL height. An option called ysu_topdown_pblmix, which provides a parameterization fog-top entrainment, has been proposed for valley fog modeling and introduced into YSU (Yonsei University) scheme in Weather Research Forecasting (WRF) model. However, enabling this simulations sea over Yellow Sea typically results unrealistic dissipation near bottom even within entire layer. In study, we theoretically examine composition then argue that one term might be redundant sea-fog modeling. The variables are employed to determine basic entrainment dry PBL, already parameterized by surface original scheme. This likely leads an overestimation rate, so refer as redundant. To explore connection between dissipation, widespread episode case study based on WRF simulation clearly attribute extra rate induces. Fog-top unexpectedly overestimated due resulting significantly drier warmer bias interior fog. When develops reaches temperature lower than surface, functions warming source heat jointly with downward flux brought leading initially occur gradually expand upwards. We suggest straightforward method modify ysu_topdown_pblmix eliminates term. improvement effect was supported sensitivity tests. more cases required validate modification method.

Language: Английский

Citations

2