Aerosol Lidar observations and model calculations of the Planetary Boundary Layer evolution over Greece, during the March 2006 Total Solar Eclipse

Abstract. An investigation of the Planetary Boundary Layer (PBL) height evolution over Greece, during the solar eclipse of 29 March 2006, is presented. Ground based observations were carried out using lidar detection and ranging devices and ground meteorological instruments, to estimate the height of the mixing layer (ML) before, during and after the solar eclipse in northern and southern parts of Greece exhibiting different sun obscuration. Data demonstrate that the solar eclipse has induced a decrease of the PBL height, indicating a suppression of turbulence activity similar to that during the sunset hours. The changes in PBL height were associated with a very shallow entrainment zone, indicating a significant weakening of the penetrative convection. Heat transfer was confined to a thinner layer above the ground. The thickness of the entrainment zone exhibited its minimum during the maximum of the eclipse, demonstrative of turbulence mechanisms suppression at that time. Model estimations of the PBL evolution were additionally conducted using the Comprehensive Air Quality Model with extensions (CAMx) coupled with the Weather Research and Forecasting model (WRF). Model-diagnosed PBL height decrease during the solar eclipse due to vertical transport decay, in agreement with the experimental findings; vertical profiles of atmospheric particles and gaseous species showed an important vertical mixing attenuation.

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Aerosol lidar observations and model calculations of the planetary boundary layer evolution over Greece, during the March 2006 total solar eclipse

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-13537-2007 ◽

2007 ◽

Vol 7 (5) ◽

pp. 13537-13560 ◽

Cited By ~ 7

Author(s):

V. Amiridis ◽

D. Melas ◽

D. S. Balis ◽

A. Papayannis ◽

D. Founda ◽

...

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Solar Eclipse ◽

Wrf Model ◽

Air Quality Model ◽

Quality Model ◽

Gaseous Species ◽

Time Model ◽

Model Calculations ◽

Entrainment Zone

Abstract. An investigation of the Planetary Boundary Layer (PBL) height evolution over Greece, during the solar eclipse of 29 March 2006, is presented. Ground based observations were carried out using lidar detection and ranging devices (Lidars) and ground meteorological instruments, to estimate the height of the Mixing Layer (ML) before, during and after the solar eclipse in Northern and Southern parts of Greece exhibiting different sun obscuration. Data demonstrate that the solar eclipse has induced a decrease of the PBL height, indicating a suppression of turbulence activity similar to that during the sunset hours. The changes in PBL height were associated with a very shallow entrainment zone, indicating a significant weakening of the penetrative convection. Heat transfer was confined to a thinner layer above ground. The thickness of the entrainment zone exhibited its minimum during the maximum of the eclipse, demonstrative of turbulence mechanisms suppression at that time. Model estimations of the PBL evolution were additionally conducted using the Comprehensive Air Quality Model with extensions (CAMx) coupled with the Weather Research and Forecasting model (WRF). Model diagnosed PBL height decrease during the solar eclipse due to vertical transport decay, in agreement with the experimental findings; vertical profiles of atmospheric particles and gaseous species showed an important vertical mixing attenuation.

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An Automated Common Algorithm for Planetary Boundary Layer Retrievals Using Aerosol Lidars in Support of the U.S. EPA Photochemical Assessment Monitoring Stations Program

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-20-0050.1 ◽

2020 ◽

Vol 37 (10) ◽

pp. 1847-1864

Author(s):

Vanessa Caicedo ◽

Ruben Delgado ◽

Ricardo Sakai ◽

Travis Knepp ◽

David Williams ◽

...

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Environmental Protection Agency ◽

Mixing Layer ◽

Residual Layer ◽

Cloud Base ◽

Retrieval Algorithm ◽

Air Quality Model ◽

Quality Model ◽

Monitoring Stations

AbstractA unique automated planetary boundary layer (PBL) retrieval algorithm is proposed as a common cross-platform method for use with commercially available ceilometers for implementation under the redesigned U.S. Environmental Protection Agency Photochemical Assessment Monitoring Stations program. This algorithm addresses instrument signal quality and screens for precipitation and cloud layers before the implementation of the retrieval method using the Haar wavelet covariance transform. Layer attribution for the PBL height is supported with the use of continuation and time-tracking parameters, and uncertainties are calculated for individual PBL height retrievals. Commercial ceilometer retrievals are tested against radiosonde PBL height and cloud-base height during morning and late-afternoon transition times, critical to air quality model prediction and when retrieval algorithms struggle to identify PBL heights. A total of 58 radiosonde profiles were used, and retrievals for nocturnal stable layers, residual layers, and mixing layers were assessed. Overall good agreement was found for all comparisons, with one system showing limitations for the cases of nighttime surface stable layers and daytime mixing layer. It is recommended that nighttime shallow stable-layer retrievals be performed with a recommended minimum height or with additional verification. Retrievals of residual-layer heights and mixing-layer comparisons revealed overall good correlations with radiosonde heights (square of correlation coefficients r2 ranging from 0.89 to 0.96, and bias ranging from approximately −131 to +63 m for the residual layer and r2 from 0.88 to 0.97 and bias from −119 to +101 m for the mixing layer).

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SOLAR ECLIPSE EFFECTS OBSERVED IN THE PLANETARY BOUNDARY LAYER OVER A DESERT

Boundary-Layer Meteorology ◽

10.1023/a:1000219210055 ◽

1997 ◽

Vol 83 (2) ◽

pp. 331-346 ◽

Cited By ~ 55

Author(s):

F. D. EATON ◽

J. R. HINES ◽

W. H. HATCH ◽

R. M. CIONCO ◽

J. BYERS ◽

...

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Solar Eclipse

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Sensitivity Study on 2013: Tropical Cyclones Using Different Cloud Microphysical and Planetary Boundary Layer Parameterisation Schemes in WRF Model

Tropical Cyclone Activity over the North Indian Ocean ◽

10.1007/978-3-319-40576-6_23 ◽

2016 ◽

pp. 337-366

Author(s):

M. Venkatarami Reddy ◽

S. B. Surendra Prasad ◽

U. V. Murali Krishna ◽

K. Krishna Reddy

Keyword(s):

Boundary Layer ◽

Tropical Cyclones ◽

Planetary Boundary Layer ◽

Wrf Model ◽

Sensitivity Study

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Estimating Daytime Planetary Boundary Layer Heights over a Valley from Rawinsonde Observations at a Nearby Airport: An Application to the Page Valley in Virginia, United States

Journal of Applied Meteorology and Climatology ◽

10.1175/jamc-d-15-0300.1 ◽

2016 ◽

Vol 55 (3) ◽

pp. 791-809 ◽

Cited By ~ 15

Author(s):

Temple R. Lee ◽

Stephan F. J. De Wekker

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Weather Forecasting ◽

Wrf Model ◽

Heat Fluxes ◽

Weather Research And Forecasting ◽

Dispersion Modeling ◽

Blue Ridge Mountains ◽

Terrain Following ◽

Regional Reanalysis

AbstractThe planetary boundary layer (PBL) height is an essential parameter required for many applications, including weather forecasting and dispersion modeling for air quality. Estimates of PBL height are not easily available and often come from twice-daily rawinsonde observations at airports, typically at 0000 and 1200 UTC. Questions often arise regarding the applicability of PBL heights retrieved from these twice-daily observations to surrounding locations. Obtaining this information requires knowledge of the spatial variability of PBL heights. This knowledge is particularly limited in regions with mountainous terrain. The goal of this study is to develop a method for estimating daytime PBL heights in the Page Valley, located in the Blue Ridge Mountains of Virginia. The approach includes using 1) rawinsonde observations from the nearest sounding station [Dulles Airport (IAD)], which is located 90 km northeast of the Page Valley, 2) North American Regional Reanalysis (NARR) output, and 3) simulations with the Weather Research and Forecasting (WRF) Model. When selecting days on which PBL heights from NARR compare well to PBL heights determined from the IAD soundings, it is found that PBL heights are higher (on the order of 200–400 m) over the Page Valley than at IAD and that these differences are typically larger in summer than in winter. WRF simulations indicate that larger sensible heat fluxes and terrain-following characteristics of PBL height both contribute to PBL heights being higher over the Page Valley than at IAD.

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An investigation of ozone and planetary boundary layer dynamics over the complex topography of Grenoble combining measurements and modeling

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-3-797-2003 ◽

2003 ◽

Vol 3 (1) ◽

pp. 797-825 ◽

Cited By ~ 1

Author(s):

O. Couach ◽

I Balin ◽

R. Jiménez ◽

P. Ristori ◽

S. Perego ◽

...

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Land Surface ◽

Mesoscale Model ◽

Ozone Production ◽

Horizontal Wind ◽

Maximum Height ◽

Complex Topography ◽

Atmospheric Measurements ◽

Model Calculations

Abstract. This paper concerns an evaluation of ozone (O3) and planetary boundary layer (PBL) dynamics over the complex topography of the Grenoble region through a combination of measurements and mesoscale model (METPHOMOD) predictions for three days, during July 1999. The measurements of O3 and PBL structure were obtained with a Differential Absorption Lidar (DIAL) system, situated 20 km south of Grenoble at Vif (310 m a.s.l.). The combined lidar observations and model calculations are in good agreement with atmospheric measurements obtained with an instrumented aircraft (METAIR). Ozone fluxes were calculated using lidar measurements of ozone vertical profiles concentrations and the horizontal wind speeds measured with a Radar Doppler wind profiler (DEGREANE). The ozone flux patterns indicate that the diurnal cycle of ozone production is controlled by local thermal winds. The convective PBL maximum height was some 2700 m above the land surface while the nighttime residual ozone layer was generally found between 1200 and 2200 m. Finally we evaluate the magnitude of the ozone processes at different altitudes in order to estimate the photochemical ozone production due to the primary pollutants emissions of Grenoble city and the regional network of automobile traffic.

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