Development of an Improved Turbulence Closure Model for the Atmospheric Boundary Layer

Nakanishi, Mikio; Niino, Hiroshi

doi:10.2151/jmsj.87.895

Cited by 798 publications

(505 citation statements)

References 48 publications

Supporting

Mentioning

447

Contrasting

Order By: Relevance

“…Rapid Radiative Transfer Model for GCMs (Iacono et al, 2008) Rapid Radiative Transfer Model for GCMs (Iacono et al, 2008) Dudhia (Dudhia, 1989) Boundary layer Yonsei University (Hong et al, 2006) Mellor-Yamada-Nakanishi-Niino (Nakanishi and Niino, 2009) Mellor-Yamada-Nakanishi-Niino (Nakanishi and Niino, 2009 Kain, 2004) previous studies focused on winter precipitation events in California, for which WRF has been more thoroughly tested than fire weather conditions (e.g. Caldwell et al, 2009;Chin et al, 2010;Smith et al, 2010;Dulière et al, 2011).…”

Section: Methodology: Model Configurationmentioning

confidence: 99%

“…Since the focus of this study is on dry conditions, we tested two additional configurations. Model configuration-2 (WRF-2) is a sensitivity test for which we replaced the boundary layer configuration used in WRF-1 with Mellor-Yamada-Nakanishi-Niino (MYNN; Nakanishi and Niino, 2009). Previous studies evaluating WRF performance in Southern California have identified PBL schemes as a primary source of error (Huang et al, 2013;Scarino et al, 2014).…”

Section: Methodology: Model Configurationmentioning

confidence: 99%

See 1 more Smart Citation

WRF simulation of downslope wind events in coastal Santa Barbara County

Cannon

Carvalho

Jones

et al. 2017

Atmospheric Research

View full text Add to dashboard Cite

The National Weather Service (NWS) considers frequent gusty downslope winds, accompanied by rapid warming and decreased relative humidity, among the most significant weather events affecting southern California coastal areas in the vicinity of Santa Barbara (SB). These extreme conditions, commonly known as "sundowners", have affected the evolution of all major wildfires that impacted SB in recent years. Sundowners greatly increase fire, aviation and maritime navigation hazards and are thus a priority for regional forecasting. Currently, the NWS employs the Weather Research Forecasting (WRF) model at 2 km resolution to complement forecasts at regional-to-local scales. However, no systematic study has been performed to evaluate the skill of WRF in simulating sundowners. This research presents a case study of an 11-day period in spring 2004 during which sundowner events were observed on multiple nights. We perform sensitivity experiments for WRF using available observations for validation and demonstrate that WRF is skillful in representing the general mesoscale structure of these events, though important shortcomings exist. Furthermore, we discuss the generation and evolution of sundowners during the case study using the best performing configuration, and compare these results to hindcasts for two major SB fires. Unique, but similar, profiles of wind and stability are observed over SB between case studies despite considerable differences in large-scale circulation, indicating that common conditions may exist across all events. These findings aid in understanding the evolution of sundowner events and are potentially valuable for event prediction.

show abstract

Section: Methodology: Model Configurationmentioning

confidence: 99%

Section: Methodology: Model Configurationmentioning

confidence: 99%

WRF simulation of downslope wind events in coastal Santa Barbara County

Cannon

Carvalho

Jones

et al. 2017

Atmospheric Research

View full text Add to dashboard Cite

show abstract

“…1), and 31 vertically staggered layers based on a terrain-following pressure coordinate system. The Mellor-Yamada-NakanishiNiino level 2.5 (MYNN; Nakanishi and Niino, 2009) is chosen as the planetary boundary scheme in this study. By using a vertical coordinate that is stretched to have higher resolutions inside the planetary boundary layer, the model has about 4-5 vertical layers inside the planetary boundary layer with a vertical resolution of ∼ 30 m near the surface.…”

Section: The Modelmentioning

confidence: 99%

Impacts of air pollutants from fire and non-fire emissions on the regional air quality in Southeast Asia

Lee

Iraqui

et al. 2018

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. Severe haze events in Southeast Asia caused by particulate pollution have become more intense and frequent in recent years. Widespread biomass burning occurrences and particulate pollutants from human activities other than biomass burning play important roles in degrading air quality in Southeast Asia. In this study, numerical simulations have been conducted using the Weather Research and Forecasting (WRF) model coupled with a chemistry component (WRF-Chem) to quantitatively examine the contributions of aerosols emitted from fire (i.e., biomass burning) versus nonfire (including fossil fuel combustion, and road dust, etc.) sources to the degradation of air quality and visibility over Southeast Asia. These simulations cover a time period from 2002 to 2008 and are driven by emissions from (a) fossil fuel burning only, (b) biomass burning only, and (c) both fossil fuel and biomass burning. The model results reveal that 39 % of observed low-visibility days (LVDs) can be explained by either fossil fuel burning or biomass burning emissions alone, a further 20 % by fossil fuel burning alone, a further 8 % by biomass burning alone, and a further 5 % by a combination of fossil fuel burning and biomass burning. Analysis of an 24 h PM 2.5 air quality index (AQI) indicates that the case with coexisting fire and non-fire PM 2.5 can substantially increase the chance of AQI being in the moderate or unhealthy pollution level from 23 to 34 %. The premature mortality in major Southeast Asian cities due to degradation of air quality by particulate pollutants is estimated to increase from ∼ 4110 per year in 2002 to ∼ 6540 per year in 2008. In addition, we demonstrate the importance of certain missing non-fire anthropogenic aerosol sources including anthropogenic fugitive and industrial dusts in causing urban air quality degradation. An experiment of using machine learning algorithms to forecast the occurrence of haze events in Singapore is also explored in this study. All of these results suggest that besides minimizing biomass burning activities, an effective air pollution mitigation policy for Southeast Asia needs to consider controlling emissions from non-fire anthropogenic sources.

show abstract

“…The friction velocity is obtained with the Charnock formula. The model simulations were run with the MYNN 1.5-order level 2.5 PBL scheme (Nakanishi and Niino, 2009), on which the WRF-WF scheme is dependent. These and other details of the model configuration are summarised in Table 2.…”

Section: Wrf Model Configuration and Averagingmentioning

confidence: 99%

The Explicit Wake Parametrisation V1.0: a wind farm parametrisation in the mesoscale model WRF

et al. 2015

View full text Add to dashboard Cite

Abstract. We describe the theoretical basis, implementation, and validation of a new parametrisation that accounts for the effect of large offshore wind farms on the atmosphere and can be used in mesoscale and large-scale atmospheric models. This new parametrisation, referred to as the Explicit Wake Parametrisation (EWP), uses classical wake theory to describe the unresolved wake expansion. The EWP scheme is validated for a neutral atmospheric boundary layer against filtered in situ measurements from two meteorological masts situated a few kilometres away from the Danish offshore wind farm Horns Rev I. The simulated velocity deficit in the wake of the wind farm compares well to that observed in the measurements, and the velocity profile is qualitatively similar to that simulated with large eddy simulation models and from wind tunnel studies. At the same time, the validation process highlights the challenges in verifying such models with real observations.

show abstract

Development of an Improved Turbulence Closure Model for the Atmospheric Boundary Layer

Cited by 798 publications

References 48 publications

WRF simulation of downslope wind events in coastal Santa Barbara County

WRF simulation of downslope wind events in coastal Santa Barbara County

Impacts of air pollutants from fire and non-fire emissions on the regional air quality in Southeast Asia

The Explicit Wake Parametrisation V1.0: a wind farm parametrisation in the mesoscale model WRF

Contact Info

Product

Resources

About