Estimation of behavior of optical turbulence duringsummer in the surface layer above the AntarcticPlateau using the Polar WRF model

2021 ◽  
Author(s):  
Qike Yang ◽  
Xiaoqing Wu ◽  
Yajuan Han ◽  
Qing Chun
Keyword(s):  
Surface Layer ◽  
Wrf Model ◽  
Optical Turbulence

scholarly journals WRF Model Experiments on the Antarctic Atmosphere in Winter

2011 ◽  
Vol 139 (4) ◽  
pp. 1279-1291 ◽  
Author(s):  
Esa-Matti Tastula ◽  
Timo Vihma
Keyword(s):  
Boundary Layer ◽  
Surface Layer ◽  
Wind Speed ◽  
Surface Pressure ◽  
Mesoscale Model ◽  
Wrf Model ◽  
Radiative Transfer Model ◽  
Transfer Model ◽  
Temperature Bias ◽  
Radiation Parameterizations

Abstract The standard and polar versions 3.1.1 of the Weather Research and Forecasting (WRF) model, both initialized by the 40-yr ECMWF Re-Analysis (ERA-40), were run in Antarctica for July 1998. Four different boundary layer–surface layer–radiation scheme combinations were used in the standard WRF. The model results were validated against observations of the 2-m temperature, surface pressure, and 10-m wind speed at 9 coastal and 2 inland stations. The best choice for boundary layer and radiation parameterizations of the standard WRF turned out to be the Yonsei University boundary layer scheme in conjunction with the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) surface layer scheme and the Rapid Radiative Transfer Model for longwave radiation. The respective temperature bias was on the order of 3°C less than the biases obtained with the other combinations. Increasing the minimum value for eddy diffusivity did, however, improve the performance of the asymmetric convective scheme by 0.8°C. Averaged over the 11 stations, the error growths in 24-h forecasts were almost identical for the standard and Polar WRF, but in 9-day forecasts Polar WRF gave a smaller 2-m temperature bias. For the Vostok station, however, the standard WRF gave a less positively biased 24-h temperature forecast. On average, the polar version gave the least biased surface pressure simulation. The wind speed simulation was characterized by low correlation values, especially under weak winds and for stations surrounded by complex topography.

Estimation of Atmospheric Optical Turbulence Profile by WRF Model at Gaomeigu

2015 ◽  
Vol 42 (9) ◽  
pp. 0913001 ◽  
Author(s):  
青春 Qing Chun ◽  
吴晓庆 Wu Xiaoqing ◽  
李学彬 Li Xuebin ◽  
朱文越 Zhu Wenyue ◽  
饶瑞中 Rao Ruizhong ◽  
...  
Keyword(s):  
Wrf Model ◽  
Optical Turbulence

Observations of optical turbulence in the marine atmospheric surface layer during CASPER-West

2018 ◽  
Author(s):  
Benjamin Wauer ◽  
Qing Wang ◽  
Oswaldo Alvarenga ◽  
Ryan Yamaguchi ◽  
John Kalogiros ◽  
...  
Keyword(s):  
Surface Layer ◽  
Atmospheric Surface Layer ◽  
Optical Turbulence

scholarly journals Monitoring the optical turbulence in the surface layer at Dome C, Antarctica, with sonic anemometers

2015 ◽  
Vol 454 (4) ◽  
pp. 4304-4315 ◽  
Author(s):  
E. Aristidi ◽  
J. Vernin ◽  
E. Fossat ◽  
F.-X. Schmider ◽  
T. Travouillon ◽  
...  
Keyword(s):  
Surface Layer ◽  
Optical Turbulence ◽  
Sonic Anemometers

scholarly journals Impacts of the Lowest Model Level Height on the Performance of Planetary Boundary Layer Parameterizations

2012 ◽  
Vol 140 (2) ◽  
pp. 664-682 ◽  
Author(s):  
Hyeyum Hailey Shin ◽  
Song-You Hong ◽  
Jimy Dudhia
Keyword(s):  
Boundary Layer ◽  
Surface Layer ◽  
Planetary Boundary Layer ◽  
Numerical Models ◽  
Wrf Model ◽  
Weather Research And Forecasting ◽  
Implicit Assumption ◽  
Convective Model ◽  
Local Scheme ◽  
Level Height

The lowest model level height z1 is important in atmospheric numerical models, since surface layer similarity is applied to the height in most of the models. This indicates an implicit assumption that z1 is within the surface layer. In this study, impacts of z1 on the performance of planetary boundary layer (PBL) parameterizations are investigated. Three conceptually different schemes in the Weather Research and Forecasting (WRF) model are tested for one complete diurnal cycle: the nonlocal, first-order Yonsei University (YSU) and Asymmetric Convective Model version 2 (ACM2) schemes and the local, 1.5-order Mellor–Yamada–Janjić (MYJ) scheme. Surface variables are sensitive to z1 in daytime when z1 is below 12 m, even though the height is within the surface layer. Meanwhile during nighttime, the variables are systematically altered as z1 becomes shallower from 40 m. PBL structures show the sensitivity in the similar manner, but weaker. The order of sensitivity among the three schemes is YSU, ACM2, and MYJ. The significant sensitivity of the YSU parameterization comes from the PBL height calculation. This is considerably alleviated by excluding the thermal excess term in determining the PBL height when z1 is within the surface layer. The factor that specifies the ratio of nonlocal transport to total mixing is critical to the sensitivity of the ACM2 scheme. The MYJ scheme has no systematic sensitivity, since it is a local scheme. It is also noted that a numerical instability appears accompanying the unrealistic PBL structures when the grid spacing in the surface layer suddenly jumps.

scholarly journals Assessing Impacts of PBL and Surface Layer Schemes in Simulating the Surface–Atmosphere Interactions and Precipitation over the Tropical Ocean Using Observations from AMIE/DYNAMO

2016 ◽  
Vol 29 (22) ◽  
pp. 8191-8210 ◽  
Author(s):  
Yun Qian ◽  
Huiping Yan ◽  
Larry K. Berg ◽  
Samson Hagos ◽  
Zhe Feng ◽  
...  
Keyword(s):  
Surface Layer ◽  
Climate Models ◽  
Deep Convection ◽  
Surface Wind ◽  
Wrf Model ◽  
Surface Fluxes ◽  
Shallow Convection ◽  
Free Atmosphere ◽  
Tropical Ocean ◽  
Surface Atmosphere

Abstract Accuracy of turbulence parameterization in representing planetary boundary layer (PBL) processes and surface–atmosphere interactions in climate models is critical for predicting the initiation and development of clouds. This study 1) evaluates WRF Model–simulated spatial patterns and vertical profiles of atmospheric variables at various spatial resolutions and with different PBL, surface layer, and shallow convection schemes against measurements; 2) identifies model biases by examining the moisture tendency terms contributed by PBL and convection processes through nudging experiments; and 3) investigates the main causes of these biases by analyzing the dependence of modeled surface fluxes on PBL and surface layer schemes over the tropical ocean. The results show that PBL and surface parameterizations have surprisingly large impacts on precipitation and surface moisture fluxes over tropical oceans. All of the parameterizations tested tend to overpredict moisture in the PBL and free atmosphere and consequently result in larger moist static energy and precipitation. Moisture nudging tends to suppress the initiation of convection and reduces the excess precipitation. The reduction in precipitation bias in turn reduces the surface wind and latent heat (LH) flux biases, which suggests the positive feedback between precipitation and surface fluxes is responsible, at least in part, for the model drifts. The updated Kain–Fritsch cumulus potential (KF-CuP) shallow convection scheme tends to suppress the deep convection, consequently decreasing precipitation. The Eta Model surface layer scheme predicts more reasonable LH fluxes and LH–wind speed relationship than those for the MM5 scheme. The results help us identify sources of biases of current parameterization schemes in reproducing PBL processes, the initiation of convection, and intraseasonal variability of precipitation.

Field and laboratory validation of surface layer optical turbulence and off-axis irradiance

2010 ◽  
Author(s):  
Steven T. Fiorino ◽  
John D. Haiducek ◽  
Christopher A. Rice ◽  
Adam D. Downs ◽  
Matthew J. Krizo ◽  
...  
Keyword(s):  
Surface Layer ◽  
Optical Turbulence
Sign in / Sign up

Export Citation Format

Share Document