Estimation on The Atmospheric Stability and Flow Characteristics of Planetary Boundary Layer in Wolryong Coastal Region

Abstract. The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia. One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and local atmospheric stability. This paper describes a case study of a 10 day period during the Spring phase of ARCTAS. It compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3–5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA) and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE). Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors. When FLAMBE provides input to the 1-D plume rise model, the resulting injection heights exhibit the best agreement with satellite-observed injection heights. The FLAMBE-derived heights are more realistic than those utilizing prep_chem_sources. Conversely, when the planetary boundary layer or the 3–5 km a.g.l. layer were filled with emissions, the resulting injection heights exhibit less agreement with observed plume heights. Results indicate that differences in injection heights produce different transport pathways. These differences are especially pronounced in area of strong vertical wind shear and when the integration period is long.

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MM5 v3.6.1 and WRF v3.2.1 model comparison of standard and surface energy variables in the development of the planetary boundary layer

Geoscientific Model Development Discussions ◽

10.5194/gmdd-7-2705-2014 ◽

2014 ◽

Vol 7 (2) ◽

pp. 2705-2743 ◽

Cited By ~ 5

Author(s):

C.-S. M. Wilmot ◽

B. Rappenglück ◽

X. Li

Keyword(s):

Boundary Layer ◽

Surface Energy ◽

Latent Heat ◽

Planetary Boundary Layer ◽

Energy Budget ◽

Model Comparison ◽

Mesoscale Model ◽

Wrf Model ◽

Coastal Region ◽

Frontal Passage

Abstract. Air quality forecasting requires atmospheric weather models to generate accurate meteorological conditions, one of which is the development of the planetary boundary layer (PBL). An important contributor to the development of the PBL is the land-air exchange captured in the energy budget as well as turbulence parameters. Standard and surface energy variables were modeled using the fifth-generation Penn State/National Center for Atmospheric Research mesoscale model (MM5), version 3.6.1, and the Weather Research and Forecasting (WRF) model, version 3.2.1, and compared to measurements for a southeastern Texas coastal region. The study period was 28 August–1 September 2006. It also included a frontal passage. The results of the study are ambiguous. Although WRF does not perform as well as MM5 in predicting PBL heights, it better simulates most of the general and energy budget variables. Both models overestimate incoming solar radiation, which implies a surplus of energy that could be redistributed in either the partitioning of the surface energy variables or in some other aspect of the meteorological modeling not examined here. The MM5 model consistently had much drier conditions than the WRF model, which could lead to more energy available to other parts of the meteorological system. On the clearest day of the study period MM5 had increased latent heat flux, which could lead to higher evaporation rates and lower moisture in the model. However, this latent heat disparity between the two models is not visible during any other part of the study. The observed frontal passage affected the performance of most of the variables, including the radiation, flux, and turbulence variables, at times creating dramatic differences in the r2 values.

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Reasons for the Extremely High-Ranging Planetary Boundary Layer over the Western Tibetan Plateau in Winter

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-15-0148.1 ◽

2016 ◽

Vol 73 (5) ◽

pp. 2021-2038 ◽

Cited By ~ 17

Author(s):

Xuelong Chen ◽

Bojan Škerlak ◽

Mathias W. Rotach ◽

Juan A. Añel ◽

Zhonbgo Su ◽

...

Keyword(s):

Boundary Layer ◽

Tibetan Plateau ◽

Sea Level ◽

Planetary Boundary Layer ◽

Weather Prediction ◽

Atmospheric Stability ◽

Small Scale ◽

The Tibetan Plateau ◽

Single Column ◽

Upper Level

Abstract The planetary boundary layer (PBL) over the Tibetan Plateau (with a mean elevation about 4 km above sea level) reaches an unmatched height of 9515 m above sea level. The proximity of this height to the tropopause facilitates an exchange between the stratosphere and the boundary layer. However, the underlying mechanisms responsible for this unique PBL have remained uncertain. Here, the authors explore these mechanisms and their relative importance using measurements of the PBL, the associated surface fluxes, and single-column and regional numerical simulations, as well as global reanalysis data. Results indicate that the dry conditions of both ground soil and atmosphere in late winter cannot explain the special PBL alone. Rather, the results from a single-column model demonstrate the key influence of the stability of the free atmosphere upon the growth of extremely deep PBLs over the Tibetan Plateau. Simulations with the numerical weather prediction model Consortium for Small-Scale Modelling (COSMO) exhibit good correspondence with the observed mean PBL structure and realistic turbulent kinetic energy distributions throughout the PBL. Using ERA-Interim, the authors furthermore find that weak atmospheric stability and the resultant deep PBLs are associated with higher upper-level potential vorticity (PV) values, which in turn correspond to a more southerly jet position and higher wind speeds. Upper-level PV structures and jet position thus influence the PBL development over the Tibetan Plateau.

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The sensitivity of dependence of large scale flow characteristics in a four-level model atmosphere on a simulated planetary boundary layer

Tellus ◽

10.1111/j.2153-3490.1975.tb01668.x ◽

1975 ◽

Vol 27 (2) ◽

pp. 145-154 ◽

Cited By ~ 1

Author(s):

J. W. Searle ◽

D. R. Davies

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Large Scale ◽

Flow Characteristics ◽

Model Atmosphere ◽

Level Model ◽

Large Scale Flow

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An investigation of methods for injecting emissions from boreal wildfires using WRF-Chem during ARCTAS

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-26551-2010 ◽

2010 ◽

Vol 10 (11) ◽

pp. 26551-26606 ◽

Cited By ~ 6

Author(s):

W. R. Sessions ◽

H. E. Fuelberg ◽

R. A. Kahn ◽

D. M. Winker

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Atmospheric Stability ◽

Vertical Wind Shear ◽

Ground Level ◽

Naval Research ◽

Plume Rise ◽

Hotspot Detection ◽

Transport Pathways ◽

Thermal Buoyancy

Abstract. The Weather Research and Forecasting Model (WRF) is considered a "next generation" mesoscale meteorology model. The inclusion of a chemistry module (WRF-Chem) allows transport simulations of chemical and aerosol species such as those observed during NASA's Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) in 2008. The ARCTAS summer deployment phase during June and July coincided with large boreal wildfires in Saskatchewan and Eastern Russia. One of the most important aspects of simulating wildfire plume transport is the height at which emissions are injected. WRF-Chem contains an integrated one-dimensional plume rise model to determine the appropriate injection layer. The plume rise model accounts for thermal buoyancy associated with fires and the local atmospheric stability. This study compares results from the plume model against those of two more traditional injection methods: Injecting within the planetary boundary layer, and in a layer 3–5 km above ground level. Fire locations are satellite derived from the GOES Wildfire Automated Biomass Burning Algorithm (WF_ABBA) and the MODIS thermal hotspot detection. Two methods for preprocessing these fire data are compared: The prep_chem_sources method included with WRF-Chem, and the Naval Research Laboratory's Fire Locating and Monitoring of Burning Emissions (FLAMBE). Results from the simulations are compared with satellite-derived products from the AIRS, MISR and CALIOP sensors. Results show that the FLAMBE pre-processor produces more realistic injection heights than does prep_chem_sources. The plume rise model using FLAMBE provides the best agreement with satellite-observed injection heights. Conversely, when the planetary boundary layer or the 3–5 km AGL layer were filled with emissions, the resulting injection heights exhibit less agreement with observed plume heights. Results indicate that differences in injection heights produce different transport pathways. These differences are especially pronounced in areas of strong vertical wind shear and when the integration period is long.

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MM5 v3.6.1 and WRF v3.5.1 model comparison of standard and surface energy variables in the development of the planetary boundary layer

Geoscientific Model Development ◽

10.5194/gmd-7-2693-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 2693-2707 ◽

Cited By ~ 5

Author(s):

C.-S. M. Wilmot ◽

B. Rappenglück ◽

X. Li ◽

G. Cuchiara

Keyword(s):

Boundary Layer ◽

Surface Energy ◽

Latent Heat ◽

Planetary Boundary Layer ◽

Energy Budget ◽

Model Comparison ◽

Mesoscale Model ◽

Wrf Model ◽

Coastal Region ◽

Frontal Passage

Abstract. Air quality forecasting requires atmospheric weather models to generate accurate meteorological conditions, one of which is the development of the planetary boundary layer (PBL). An important contributor to the development of the PBL is the land–air exchange captured in the energy budget as well as turbulence parameters. Standard and surface energy variables were modeled using the fifth-generation Penn State/National Center for Atmospheric Research mesoscale model (MM5), version 3.6.1, and the Weather Research and Forecasting (WRF) model, version 3.5.1, and compared to measurements for a southeastern Texas coastal region. The study period was 28 August–1 September 2006. It also included a frontal passage. The results of the study are ambiguous. Although WRF does not perform as well as MM5 in predicting PBL heights, it better simulates energy budget and most of the general variables. Both models overestimate incoming solar radiation, which implies a surplus of energy that could be redistributed in either the partitioning of the surface energy variables or in some other aspect of the meteorological modeling not examined here. The MM5 model consistently had much drier conditions than the WRF model, which could lead to more energy available to other parts of the meteorological system. On the clearest day of the study period, MM5 had increased latent heat flux, which could lead to higher evaporation rates and lower moisture in the model. However, this latent heat disparity between the two models is not visible during any other part of the study. The observed frontal passage affected the performance of most of the variables, including the radiation, flux, and turbulence variables, at times creating dramatic differences in the r2 values.

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Convective Planetary Boundary Layer Interactions with the Land Surface at Diurnal Time Scales: Diagnostics and Feedbacks

Journal of Hydrometeorology ◽

10.1175/jhm614.1 ◽

2007 ◽

Vol 8 (5) ◽

pp. 1082-1097 ◽

Cited By ~ 53

Author(s):

Joseph A. Santanello ◽

Mark A. Friedl ◽

Michael B. Ek

Keyword(s):

Boundary Layer ◽

Soil Moisture ◽

Planetary Boundary Layer ◽

Mixed Layer ◽

Land Surface ◽

Atmospheric Stability ◽

Surface Fluxes ◽

Surface Model ◽

Wide Range ◽

Convective Planetary Boundary Layer

Abstract The convective planetary boundary layer (PBL) integrates surface fluxes and conditions over regional and diurnal scales. As a result, the structure and evolution of the PBL contains information directly related to land surface states. To examine the nature and magnitude of land–atmosphere coupling and the interactions and feedbacks controlling PBL development, the authors used a large sample of radiosonde observations collected at the southern Atmospheric Research Measurement Program–Great Plains Cloud and Radiation Testbed (ARM-CART) site in association with simulations of mixed-layer growth from a single-column PBL/land surface model. The model accurately predicts PBL evolution and realistically simulates thermodynamics associated with two key controls on PBL growth: atmospheric stability and soil moisture. The information content of these variables and their influence on PBL height and screen-level temperature can be characterized using statistical methods to describe PBL–land surface coupling over a wide range of conditions. Results also show that the first-order effects of land–atmosphere coupling are manifested in the control of soil moisture and stability on atmospheric demand for evapotranspiration and on the surface energy balance. Two principal land–atmosphere feedback regimes observed during soil moisture drydown periods are identified that complicate direct relationships between PBL and land surface properties, and, as a result, limit the accuracy of uncoupled land surface and traditional PBL growth models. In particular, treatments for entrainment and the role of the residual mixed layer are critical to quantifying diurnal land–atmosphere interactions.

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