Atmospheric Boundary Layer Processes, Characteristics and Parameterization

A special issue of Atmosphere (ISSN 2073-4433). This special issue belongs to the section "Meteorology".

Deadline for manuscript submissions: closed (20 January 2023) | Viewed by 22823

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Guest Editor
School of Atmospheric Physics, Nanjing University of Information Science & Technology, Nanjing 210044, China
Interests: tropical cyclones; atmospheric boundary layer; air-land-sea interaction; air pollution
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Shanghai Typhoon Institute of China Meteorological Administration, Shanghai 200030, China
Interests: tropical cyclone boundary layer; typhoon field experiment; extratropical transition
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Special Issue Information

Dear Colleagues,

The atmospheric boundary layer is distinguished from the rest of the atmosphere due to its unique characteristics, i.e., direct interaction with the Earth’s surface and active turbulence. Understanding the dynamic and chemical processes in the boundary layer is of great importance in weather and air quality forecasting. Recently, with the improvement of observation and simulation techniques, our understanding of atmospheric boundary layer processes and characteristics has significantly improved. For example, the ultrasonic anemometer and large aperture scintillometer can provide information around turbulent exchanges, while the large eddy simulation technique simulates the detailed structure of turbulent eddies. This Special Issue is dedicated to reporting new findings with regard to atmospheric boundary layer processes, characteristics, and parametrization methods, including but not limited to turbulent exchange, transportation, and their parametrization; boundary layer jet; local atmospheric circulation; surface energy partitioning; atmospheric stability condition; pollutant distribution and transportation; etc.

Prof. Dr. Yubin Li
Prof. Dr. Jie Tang
Guest Editors

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Keywords

  • atmospheric boundary layer
  • turbulent exchange
  • boundary layer jet
  • local atmospheric circulation
  • surface energy partitioning
  • pollutant transportation

Published Papers (13 papers)

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Editorial

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3 pages, 175 KiB  
Editorial
Atmospheric Boundary Layer Processes, Characteristics and Parameterization
by Yubin Li and Jie Tang
Atmosphere 2023, 14(4), 691; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos14040691 - 07 Apr 2023
Cited by 1 | Viewed by 1238
Abstract
The atmospheric boundary layer is distinguished from the rest of the atmosphere due to its unique characteristics, i [...] Full article

Research

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16 pages, 1559 KiB  
Article
Numerical Investigation on Impact Erosion of Aeolian Sand Saltation in Gobi
by Yong Wang, Jie Zhang, Hongchao Dun and Ning Huang
Atmosphere 2023, 14(2), 349; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos14020349 - 09 Feb 2023
Cited by 3 | Viewed by 1433
Abstract
Sand drift erosion is common on aeolian landforms, particularly in the Gobi desert where sand drift is often quite strong. Sand drift erosion can lead to many types of hazards, including severe crop loss, structural damage to buildings or infrastructure, and abrasion of [...] Read more.
Sand drift erosion is common on aeolian landforms, particularly in the Gobi desert where sand drift is often quite strong. Sand drift erosion can lead to many types of hazards, including severe crop loss, structural damage to buildings or infrastructure, and abrasion of soil or clay components that contribute to the production of fine particulate matter. This article combines the Gobi sand flow model with the solid particles erosion model to simulate the sand drift erosion process in a variety of Gobi environments. The results show that the impact erosion of saltation particles is highly dependent on both the friction velocity and the gravel coverage. Saltation erosion amount increases with the increment of friction velocity and the gravel coverage. The vertical profile of saltating erosion rate displays a clear stratification pattern composed of a linear increasing layer, a damage layer, and a monotonic decreasing layer. The maximum value of the saltation erosion rate increases as the friction velocity increases and their curve shows a power-law relationship. The damage height caused by saltation erosion is primarily concentrated in the height range of 0.03 m to 0.15 m, and it increases approximately linearly with friction velocity. Full article
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16 pages, 6503 KiB  
Article
Evaluation of Air–Sea Flux Parameterization for Typhoon Mangkhut Simulation during Intensification Period
by Lei Ye, Yubin Li and Zhiqiu Gao
Atmosphere 2022, 13(12), 2133; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13122133 - 19 Dec 2022
Cited by 2 | Viewed by 1199
Abstract
Using the Advanced Research Weather Research and Forecasting (WRF) model, a series of numerical experiments are conducted to examine the sensitivity of the Typhoon Mangkhut intensification simulation to different air–sea flux parameterization schemes (isftcflx option), including option 0 (OPT0), option 1 (OPT1), [...] Read more.
Using the Advanced Research Weather Research and Forecasting (WRF) model, a series of numerical experiments are conducted to examine the sensitivity of the Typhoon Mangkhut intensification simulation to different air–sea flux parameterization schemes (isftcflx option), including option 0 (OPT0), option 1 (OPT1), and option 2 (OPT2). The results show that three schemes basically reproduce tropical cyclone (TC) track and intensity of observation, and the simulated exchange coefficient of three schemes is consistent with theoretical results. Using the same upper limit of Cd as OPT0 and OPT2, OPT1 has much larger Ck than the other two options, which leads to larger latent heat (and sensible heat) flux and produces stronger inflow (within boundary layer) and updrafts (around eyewall), and thus stronger TC intensity. Meanwhile, the results that larger Ck/Cd corresponds with stronger TC in the mature stage are consistent with Emanuel’s potential intensity theory. The fact that Ck in OPT1 is evidently larger than the Ck from previous studies leads to produce a better TC intensity simulation. Generally, we should use more reasonable air–sea flux parameterization based on observation to improve TC intensity simulation. Full article
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19 pages, 3249 KiB  
Article
Correction to a Simple Biosphere Model 2 (SiB2) Simulation of Energy and Carbon Dioxide Fluxes over a Wheat Cropland in East China Using the Random Forest Model
by Shiqi Zhang, Zexia Duan, Shaohui Zhou and Zhiqiu Gao
Atmosphere 2022, 13(12), 2080; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13122080 - 10 Dec 2022
Cited by 1 | Viewed by 1112
Abstract
Modeling the heat and carbon dioxide (CO2) exchanges in agroecosystems is critical for better understanding water and carbon cycling, improving crop production, and even mitigating climate change, in agricultural regions. While previous studies mainly focused on simulations of the energy and [...] Read more.
Modeling the heat and carbon dioxide (CO2) exchanges in agroecosystems is critical for better understanding water and carbon cycling, improving crop production, and even mitigating climate change, in agricultural regions. While previous studies mainly focused on simulations of the energy and CO2 fluxes in agroecosystems on the North China Plain, their corrections, simulations and driving forces in East China are less understood. In this study, the dynamic variations of heat and CO2 fluxes were simulated by a standalone version of the Simple Biosphere 2 (SiB2) model and subsequently corrected using a Random Forest (RF) machine learning model, based on measurements from 1 January to 31 May 2015–2017 in eastern China. Through validation with direct measurements, it was found that the SiB2 model overestimated the sensible heat flux (H) and latent heat flux (LE), but underestimated soil heat flux (G0) and CO2 flux (Fc). Thus, the RF model was used to correct the results modeled by SiB2. The RF model showed that disturbances in temperature, net radiation, the G0 output of SiB2, and the Fc output of SiB2 were the key driving factors modulating the H, LE, G0, and Fc. The RF model performed well and significantly reduced the biases for H, LE, G0, and Fc simulated by SiB2, with higher R2 values of 0.99, 0.87, 0.75, and 0.71, respectively. The SiB2 and RF models combine physical mechanisms and mathematical correction to enable simulations with both physical meaning and accuracy. Full article
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18 pages, 7624 KiB  
Article
The Impacts of Wind Shear on Spatial Variation of the Meteorological Element Field in the Atmospheric Convective Boundary Layer Based on Large Eddy Simulation
by Hailiang Zhang, Jinfang Yin, Qing He and Minzhong Wang
Atmosphere 2022, 13(10), 1567; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13101567 - 25 Sep 2022
Cited by 2 | Viewed by 1572
Abstract
As wind shear increases, the quasi-two-dimensional structure of flows becomes more significant in the convective boundary layer (CBL), indicating that wind shear plays an essential role in the variation of the field of atmospheric flow. Therefore, sensitive numerical experiments based on Large Eddy [...] Read more.
As wind shear increases, the quasi-two-dimensional structure of flows becomes more significant in the convective boundary layer (CBL), indicating that wind shear plays an essential role in the variation of the field of atmospheric flow. Therefore, sensitive numerical experiments based on Large Eddy Simulation (LES) techniques were conducted to comprehensively investigate the effects of wind shear on the spatial variations in the velocity and potential temperature (θ) horizontal fields. Under the constant surface heat flux condition, the main findings are summarized. Firstly, in the CBL, the variances of the streamwise velocity (u), cross-stream velocity (v), and θ enhance as wind shear increases, whereas the variance of vertical velocity (w) is insensitive to wind shear. Secondly, in the CBL, with increasing wind shear, low-wavenumber Power Spectrum Densities (PSDs) of u, v, w, and θ increase significantly, suggesting that the increasing wind shear always enhances the large-scale motions of the atmosphere (i.e., low-wavenumber PSD). Therefore, it is more likely that some mesoscale weather processes will be triggered. Thirdly, generally, in the high-wavenumber range, with increasing wind shear, the PSDs of u, v, and θ increase slightly, whereas the PSD of w decreases slightly. This study provides a new perspective for understanding the role of wind shear in the spatial variations of the horizontal fields of meteorological elements under the same conditions of surface heat flux. Full article
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16 pages, 1757 KiB  
Article
A Simple Parameterization to Enhance the Computational Time in the Three Layer Dry Deposition Model for Smooth Surfaces
by Omar M. M. Nofal, Omar Al-Jaghbeer, Zaid Bakri and Tareq Hussein
Atmosphere 2022, 13(8), 1190; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13081190 - 27 Jul 2022
Cited by 1 | Viewed by 1543
Abstract
Optimization of dry deposition velocity calculation has been of great interest. Every time, determining the value of the concentration boundary layer (CBL) thickness led to a waste of numerical calculation time, which appears as a huge time in large-scale climate models. The goal [...] Read more.
Optimization of dry deposition velocity calculation has been of great interest. Every time, determining the value of the concentration boundary layer (CBL) thickness led to a waste of numerical calculation time, which appears as a huge time in large-scale climate models. The goal of this study is to optimize the numerical calculation time in the three-layer deposition model for smooth surfaces through the development of a MATLAB code that can parameterize the appropriate concentration boundary layer height (y+cbl) and internal integral calculation intervals for each particle diameter Dp (0.01–100 µm) and friction velocity u* (0.01–100 m/s). The particle concentration, as a solution to the particle flux equation, is obtained and modeled numerically by performing the left Riemann sum using MATLAB software. On the other hand, the number of subdivisions N of the Riemann sum was also parameterized for each Dp and u* in order to lessen the numerical calculation time. From a numerical point of view, the new parameterizations were tested by several computers; about 78% on the average of the computation time was saved when compared with the original algorithm. In other words, on average, about 1.2 s/calculation was gained, which is valuable in climate models simulations when millions of dry deposition calculations are needed. Full article
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20 pages, 3977 KiB  
Article
Vertical Eddy Diffusivity in the Tropical Cyclone Boundary Layer during Landfall
by Chen Chen
Atmosphere 2022, 13(6), 982; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13060982 - 17 Jun 2022
Cited by 1 | Viewed by 1649
Abstract
This study investigated surface layer turbulence characteristics and parameters using 20 Hz eddy covariance data collected from five heights with winds up to 42.27 m s−1 when Super Typhoon Maria (2018) made landfall. The dependence of these parameters including eddy diffusivities for [...] Read more.
This study investigated surface layer turbulence characteristics and parameters using 20 Hz eddy covariance data collected from five heights with winds up to 42.27 m s−1 when Super Typhoon Maria (2018) made landfall. The dependence of these parameters including eddy diffusivities for momentum (Km) and heat (Kt), vertical mixing length (Lm), and strain rate (S) on wind speed (un), height, and radii was examined. The results show that momentum fluxes (τ), turbulent kinetic energy (TKE), and Km had a parabolic dependence on un at all five heights outside three times the RMW, the maximum of Km and S increased from the surface to a maximum value at a height of 50 m, and then decreased with greater heights. However, Km and S were nearly constant with wind and height within two to three times the RMW from the TC center before landfall. Our results also found the |τ|, TKE, and Km were larger than over oceanic areas at any given wind, and Km was about one to two orders of magnitude bigger than Kt. The turbulence characteristic and parameters’ change with height and radii from the TC center should be accounted for in sub-grid scale physical processes of momentum fluxes in numerical TC models. Full article
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16 pages, 5615 KiB  
Article
Assessing Spatial Variation of PBL Height and Aerosol Layer Aloft in São Paulo Megacity Using Simultaneously Two Lidar during Winter 2019
by Gregori de Arruda Moreira, Amauri Pereira de Oliveira, Georgia Codato, Maciel Piñero Sánchez, Janet Valdés Tito, Leonardo Alberto Hussni e Silva, Lucas Cardoso da Silveira, Jonatan João da Silva, Fábio Juliano da Silva Lopes and Eduardo Landulfo
Atmosphere 2022, 13(4), 611; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13040611 - 11 Apr 2022
Cited by 4 | Viewed by 1806
Abstract
This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and [...] Read more.
This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and relatively flat area of São Paulo for two winter months of 2019. The results showed that the PBLH differences display diurnal variation that depends on the PBL during daytime growth phases. Cloud and sea breeze effects control most of PBLH variation. In the absence of cloud and sea breeze, the maximum difference (~300 m) occurs in the rapid development stage and is due to topographic effects. When the PBL approaches its maximum daily value, it tends to level off with respect to the topography. In addition, it was presented a method that combines elastic lidar (to detect an aerosol layer) and satellite data (to classify such a layer from Aerosol Optical Depth (AOD) and Aerosol Index (AI) information) for the detection of biomass burning events. This methodology demonstrated that the variations caused by Biomass Burning in AOD and AI enable both the detection of aerosol plumes originating from biomass burning and the identification of their origin. Full article
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23 pages, 2079 KiB  
Article
An Evaluation of Algebraic Turbulence Length Scale Formulations
by Stephanie Reilly, Ivan Bašták Ďurán, Anurose Theethai Jacob and Juerg Schmidli
Atmosphere 2022, 13(4), 605; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13040605 - 09 Apr 2022
Cited by 1 | Viewed by 1855
Abstract
Turbulence kinetic energy (TKE) schemes are routinely used for turbulence parameterization in numerical weather prediction models. A key component of these schemes is the so-called turbulence length scale. Novel scale-aware, budget-based diagnostics that account for the cross-scale transfer of variances are used to [...] Read more.
Turbulence kinetic energy (TKE) schemes are routinely used for turbulence parameterization in numerical weather prediction models. A key component of these schemes is the so-called turbulence length scale. Novel scale-aware, budget-based diagnostics that account for the cross-scale transfer of variances are used to evaluate the performance of selected turbulence length scale formulations in the gray zone of turbulence. The diagnostics are computed using the coarse-graining method on high resolution large eddy simulation data for selected idealized cases. The vertical profiles and the temporal evolution of the turbulence length scales are analyzed. Additionally, the local normalized root mean square error and a non-local three-component technique tailored specifically to the turbulence length scale profiles are used for the evaluation. Based on our analyses, we recommend using turbulence length-scale formulations that depend not only on the boundary layer height, but also on the TKE and stratification. Such formulations are able to perform satisfactorily in different flow regimes, but their scale-awareness is still limited. Only the Honnert et al. formulation shows a stronger scale-awareness thanks to its cut-off relationship in the gray zone. However, in contrast to the turbulence length scale diagnostics, its resolution dependence does not change with height. Full article
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18 pages, 8060 KiB  
Article
Influences of MJO on the Diurnal Variation and Associated Offshore Propagation of Rainfall near Western Coast of Sumatra
by Bojun Zhu, Yu Du and Zhiqiu Gao
Atmosphere 2022, 13(2), 330; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13020330 - 16 Feb 2022
Cited by 8 | Viewed by 2507
Abstract
Madden-Julian Oscillation (MJO) plays an important role in modulating precipitation at Maritime Continent (MC) not only on a larger scale, but also in the diurnal cycle. Diurnal rainfall offshore propagation is one of the most evident features near coasts. This study investigates the [...] Read more.
Madden-Julian Oscillation (MJO) plays an important role in modulating precipitation at Maritime Continent (MC) not only on a larger scale, but also in the diurnal cycle. Diurnal rainfall offshore propagation is one of the most evident features near coasts. This study investigates the impacts of MJO on diurnal rainfall and its offshore propagation at the western coast of Sumatra during boreal winters using ERA5 reanalysis. The real-time multivariate MJO (RMM) index was applied to locate the active MJO convection through eight different phases, in the western hemisphere and Africa in P8–P1, at the Indian Ocean in P2–P3, at MC in P4–P5, and the western Pacific Ocean in P6–P7. The rainfall characteristics, including the daily rate, the absolute and normalized diurnal variation amplitudes, and the strengths of diurnal offshore propagation, not only depend on active/inactive MJO stages but also vary under different MJO phases, through the combined modulations of large-scale backgrounds and local-scale land–sea circulations. The offshore rainfall propagation is associated with meso-large-scale gravity waves generated from land–sea thermal contrast and thus is affected by the radiation effect of cloud under different MJO phases. The stronger wave signals in P8–P1 and P6–P7 enhance the diurnal rainfall variation amplitudes away from the coast, while the strong coupling of moist convection with gravity waves contributes greatly to the diurnal rainfall cycle in P2–P3. Full article
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12 pages, 3637 KiB  
Article
Surface Layer Drag Coefficient at Different Radius Ranges in Tropical Cyclones
by Lei Ye, Yubin Li and Zhiqiu Gao
Atmosphere 2022, 13(2), 280; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13020280 - 08 Feb 2022
Cited by 2 | Viewed by 1665
Abstract
Using dropsonde data and a flux-profile method, this study investigates the drag coefficient (Cd)–wind speed relationship within different radius ranges. The results show a systematic decrease of friction velocity u* from the range of R/RMW > 1.05 to that [...] Read more.
Using dropsonde data and a flux-profile method, this study investigates the drag coefficient (Cd)–wind speed relationship within different radius ranges. The results show a systematic decrease of friction velocity u* from the range of R/RMW > 1.05 to that of R/RMW < 0.95 (R is the radial location of a dropsonde profile, and RMW is the radius of maximum wind), and the reduction is 5~25% for different wind speeds. Further, within the ranges of either R/RMW > 1.05 or R/RMW < 1.05, a clear feature of “roll-off” at about 35 m s−1 can be obtained. However, the roll feature becomes vague in the ranges of R/RMW < 0.95, R/RMW < 0.85, and R/RMW < 0.75, indicating the TC dynamics within and near RMW play a role in affecting the flux-profile relationship. Even more, Cd of R < 0.75RMW deviates significantly from the Cd of R < 0.85RMW and R < 0.95RMW, while the deviation between R < 0.85RMW and R < 0.95RMW is much smaller. Especially when 10 m winds exceed 40 m s−1, u* of R < 0.75RMW is significantly larger than that of R < 0.85RMW. This phenomenon is also linked to the TC dynamics (e.g., the large radial gradients of winds and the drastic vertical variation of the bulk Richardson number), but the speculation needs to be verified in future study. Full article
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24 pages, 9005 KiB  
Article
Effects of Periodic Tidal Elevations on the Air-Sea Momentum and Turbulent Heat Fluxes in the East China Sea
by Yuting Han, Yuxin Liu, Xingwei Jiang, Mingsen Lin, Yangang Li, Bo Yang, Changsan Xu, Lingling Yuan, Jingxin Luo, Kexiu Liu, Xingrong Chen, Fujiang Yu and Xiangzhou Song
Atmosphere 2022, 13(1), 90; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos13010090 - 06 Jan 2022
Cited by 3 | Viewed by 1459
Abstract
Using bulk formulas, two-year platform (fastened to the seabed) hourly observations from 2016 to 2017 in the East China Sea (121.6° E, 32.4° N) are used to investigate the role of the tide-induced surface elevation in changing the fixed observational height and modifying [...] Read more.
Using bulk formulas, two-year platform (fastened to the seabed) hourly observations from 2016 to 2017 in the East China Sea (121.6° E, 32.4° N) are used to investigate the role of the tide-induced surface elevation in changing the fixed observational height and modifying the momentum and air-sea turbulent heat fluxes. The semidiurnal tide-dominated elevation anomalies ranging from −3.6 to 3.9 m change the fixed platform observational height. This change causes hourly differences in the wind stress and latent and sensible heat fluxes between estimates with and without considering surface elevation, with values ranging from −1.5 × 10−3 Nm−2, −10.2 Wm−2, and −3.6 Wm−2 to 2.2 × 10−3 Nm−2, 8.4 Wm−2, and 4.6 Wm−2, respectively. More significant differences occur during spring tides. The differences show weak dependence on the temperature, indicating weak seasonal variations. The mean (maximum) difference percentage relative to the mean magnitude is approximately 3.5% (7%), 1.5% (3%), and 1.5% (3%) for the wind stress and latent and sensible heat fluxes, respectively. The boundary layer stability (BLS) can convert from near-neutral conditions to stable and unstable states in response to tide-induced changes in the observational height, with a probability of occurrence of 2%. Wind anomalies play dominant roles in determining the hourly anomalies of the latent heat flux, regardless of the state of the BLS. Extreme cases, including the cold air outbreak in 2016, tropical cyclones Meranti in 2016, and Ampil in 2018, are also examined. This study will facilitate future observation-reanalysis comparisons in the studied coastal region where ocean–atmosphere-land interactive processes are significant. Full article
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9 pages, 1510 KiB  
Article
Parameterization of Sea Surface Drag Coefficient for All Wind Regimes Using 11 Aircraft Eddy-Covariance Measurement Databases
by Zhiqiu Gao, Shaohui Zhou, Jianbin Zhang, Zhihua Zeng and Xueyan Bi
Atmosphere 2021, 12(11), 1485; https://0-doi-org.brum.beds.ac.uk/10.3390/atmos12111485 - 10 Nov 2021
Cited by 4 | Viewed by 1763
Abstract
The drag coefficient is essential for calculating the aerodynamic friction between air and sea. In this study, we regress a set of relationships between the drag coefficient and the wind speed for different wind ranges using an observational dataset that consists of 5941 [...] Read more.
The drag coefficient is essential for calculating the aerodynamic friction between air and sea. In this study, we regress a set of relationships between the drag coefficient and the wind speed for different wind ranges using an observational dataset that consists of 5941 estimates of the mean flow and fluxes from 11 aircraft turbulent measurements over the sea surface. Results show that: (1) the drag coefficient is a power function of wind speed over smooth sea surface when it is no greater than 4.5 ms−1, and the drag coefficient decreases with the increase of wind speed; and (2) for rough sea surface, when the wind speed is greater than 4.5 ms−1 and less than or equal to 10.5 ms−1, the drag coefficient increases linearly with the increase of horizontal wind speed; when the wind speed is greater than 10.5 ms−1 and less than or equal to 33.5 ms−1, the drag coefficient changes parabolically with the increase of wind speed; when the wind speed is greater than 33.5 ms−1, the drag coefficient is constant. Additionally, regressed from drag coefficient, the saturated wind speed threshold is 23 ms−1. Parameterizations of turbulent heat transfer coefficient (Ch) and water vapor transfer coefficient (Ce) are also investigated. Full article
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