Representation of the Subgrid-Scale Turbulent Transport in Convective Boundary Layers at Gray-Zone Resolutions

Shin, Hyeyum Hailey; Hong, Song‐You

doi:10.1175/mwr-d-14-00116.1

Cited by 248 publications

(192 citation statements)

References 66 publications

(85 reference statements)

Supporting

Mentioning

184

Contrasting

Unclassified

Order By: Relevance

“…These parameterizations were mainly derived by large eddy simulation (LES) models (e.g., Mellor and Yamada, 1982;Hong et al, 2006;Hong, 2007;Nakanishi and Niino, 2009;Shin and Hong, 2015) and only to a minor extent by observations. Vertical and horizontal moisture transports via mesoscale circulations and surface heterogeneities can result in convection initiation (CI) as well as the formation of clouds and precipitation (e.g., Behrendt et al, 2011; Corsmeier et al, 2011), which are very difficult to be observed from space (e.g., Aoshima et al, 2008).…”

Section: Introductionmentioning

confidence: 99%

3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

et al. 2016

View full text Add to dashboard Cite

Abstract. High-resolution three-dimensional (3-D) water vapor data of the atmospheric boundary layer (ABL) are required to improve our understanding of land-atmosphere exchange processes. For this purpose, the scanning differential absorption lidar (DIAL) of the University of Hohenheim (UHOH) was developed as well as new analysis tools and visualization methods. The instrument determines 3-D fields of the atmospheric water vapor number density with a temporal resolution of a few seconds and a spatial resolution of up to a few tens of meters. We present three case studies from two field campaigns. In spring 2013, the UHOH DIAL was operated within the scope of the HD(CP) 2 Observational Prototype Experiment (HOPE) in western Germany. HD(CP) 2 stands for High Definition of Clouds and Precipitation for advancing Climate Prediction and is a German research initiative. Range-height indicator (RHI) scans of the UHOH DIAL show the water vapor heterogeneity within a range of a few kilometers up to an altitude of 2 km and its impact on the formation of clouds at the top of the ABL. The uncertainty of the measured data was assessed for the first time by extending a technique to scanning data, which was formerly applied to vertical time series. Typically, the accuracy of the DIAL measurements is between 0.5 and 0.8 g m −3 (or < 6 %) within the ABL even during daytime. This allows for performing a RHI scan from the surface to an elevation angle of 90 • within 10 min. In summer 2014, the UHOH DIAL participated in the Surface Atmosphere Boundary Layer Exchange (SABLE) campaign in southwestern Germany. Conical volume scans were made which reveal multiple water vapor layers in three dimensions. Differences in their heights in different directions can be attributed to different surface elevation. With low-elevation scans in the surface layer, the humidity profiles and gradients can be related to different land cover such as maize, grassland, and forest as well as different surface layer stabilities.

show abstract

Section: Introductionmentioning

confidence: 99%

3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Adaptations to the grey zones have been 114 made by various groups (e.g. Boutle et al 2014, Ito et al 2015, Shin and Hong 2015 and 115 Honnert et al 2016) but such approaches are strongly related to the selected PBL and surface 116 layer schemes. Therefore, over the entire range of model scales from 10s of meters to 10s of 117 kilometers, it is necessary to study the representation of L-A interactions.…”

mentioning

confidence: 99%

A New Research Approach for Observing and Characterizing Land–Atmosphere Feedback

Wulfmeyer

Turner

Baker

et al. 2018

Bulletin of the American Meteorological Society

View full text Add to dashboard Cite

38Forecast errors with respect to wind, temperature, moisture, clouds, and precipitation largely 39 correspond to the limited capability of current earth system models to capture and simulate 40 land-atmosphere feedback. To facilitate its realistic simulation in next generation models, an 41 improved process understanding of the related complex interactions is essential. To this end, 42 accurate 3D observations of key variables in the land-atmosphere (L-A) system with high 43 vertical and temporal resolution from the surface to the free troposphere are indispensable. 44Recently, we developed a synergy of innovative ground-based, scanning active remote sens-45 ing systems for 2D to 3D measurements of wind, temperature, and water vapor from the sur-46 face to the lower troposphere that is able to provide comprehensive data sets for characteriz-47 Motivation 71The land-atmosphere (L-A) system includes the soil, the land cover such as vegetation, and 72 the overlying atmosphere. The interaction of variables, e.g. related to the water and energy 73 budgets, results in characteristic natural variabilities and regimes as well as their changes due 74 to anthropogenic influences. The planetary boundary layer (PBL) is part of the L-A system 75 and represents the interface between the land surface and the free troposphere. Through an 76 exchange of momentum, energy and water, the dynamics, the thermodynamic structure, and 77 the evolution of the PBL affect the formation of shallow and deep clouds, convection initia-78 tion, and thus precipitation (Sherwood et al. 2010, Behrendt et al. 2011, Santanello et al. 79 2011, van den Hurk et al. 2011. One of the most complex feedback 80 loops is between soil moisture and precipitation (Seneviratne et al. 2010, Guillod et al. 2015, 81 Santanello et al. 2017). Precipitation can be influenced directly by the surface fluxes (Ek and 82Holtslag 2004), and indirectly via PBL dynamics and mesoscale circulations (Taylor et al. 83 2012). 84The PBL state and its evolution are strongly influenced by non-linear feedbacks in the L-A 85 system. These are due to two-way interactions between radiation, soil, vegetation, and atmos-86 pheric variables, which result in the diurnal cycles of surface fluxes. The feedbacks are rele-87 vant from local to global scales (Mahmood et al. 2013, Stéfanon et al. 2014, and their 88 strength varies both regionally and seasonally in dependence of soil moisture, advection, and 89 climate regimes. In locations where these feedbacks play an important role, it is likely that 90 they will become even more important due to anthropogenic climate change (Dirmeyer et al. 91 2012). Thus, to improve our understanding of the state and the evolution of the L-A system as 92 well as the dynamics and thermodynamics of the PBL, it is critical that feedbacks and fluxes 93 between the different components, including entrainment at the top of the PBL, are well char-94 4 acterized and appropriately represented in weather, climate, and earth system models (e.g., 95 Se...

show abstract

“…Ito et al (2015) extended the Mellor and Yamada scheme by modifying the length scales using statistics obtained from LES coarse-graining. Shin and Hong (2015) quantified the local and non-local turbulence at scales in the grey zone to adjust the vertical profiles resulting from their non-local K-gradient scheme.…”

Section: Introductionmentioning

confidence: 99%

Representation of the grey zone of turbulence in the atmospheric boundary layer

Honnert¹

2016

Adv. Sci. Res.

View full text Add to dashboard Cite

Abstract. Numerical weather prediction model forecasts at horizontal grid lengths in the range of 100 to 1 km are now possible. This range of scales is the "grey zone of turbulence". Previous studies, based on large-eddy simulation (LES) analysis from the MésoNH model, showed that some assumptions of some turbulence schemes on boundary-layer structures are not valid. Indeed, boundary-layer thermals are now partly resolved, and the subgrid remaining part of the thermals is possibly largely or completely absent from the model columns. First, some modifications of the equations of the shallow convection scheme have been tested in the MésoNH model and in an idealized version of the operational AROME model at resolutions coarser than 500 m. Secondly, although the turbulence is mainly vertical at mesoscale ( > 2 km resolution), it is isotropic in LES (< 100 m resolution). It has been proved by LES analysis that, in convective boundary layers, the horizontal production of turbulence cannot be neglected at resolutions finer than half of the boundary-layer height. Thus, in the grey zone, fully unidirectional turbulence scheme should become tridirectional around 500 m resolution. At Météo-France, the dynamical turbulence is modelled by a K-gradient in LES as well as at mesoscale in both MésoNH and AROME, which needs mixing lengths in the formulation. Vertical and horizontal mixing lengths have been calculated from LES of neutral and convective cases at resolutions in the grey zone.

show abstract

Representation of the Subgrid-Scale Turbulent Transport in Convective Boundary Layers at Gray-Zone Resolutions

Cited by 248 publications

References 66 publications

3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

3-D water vapor field in the atmospheric boundary layer observed with scanning differential absorption lidar

A New Research Approach for Observing and Characterizing Land–Atmosphere Feedback

Representation of the grey zone of turbulence in the atmospheric boundary layer

Contact Info

Product

Resources

About