Dual-Doppler lidar observation of horizontal convective rolls and near-surface streaks

2008 ◽  
Vol 35 (14) ◽  
Author(s):  
Hironori Iwai ◽  
Shoken Ishii ◽  
Nobumitsu Tsunematsu ◽  
Kohei Mizutani ◽  
Yasuhiro Murayama ◽  
...  
Keyword(s):  
Doppler Lidar ◽  
Near Surface ◽  
Lidar Observation ◽  
Convective Rolls

scholarly journals Wind Energy Meteorology: Insight into Wind Properties in the Turbine-Rotor Layer of the Atmosphere from High-Resolution Doppler Lidar

2013 ◽  
Vol 94 (6) ◽  
pp. 883-902 ◽  
Author(s):  
Robert M. Banta ◽  
Yelena L. Pichugina ◽  
Neil D. Kelley ◽  
R. Michael Hardesty ◽  
W. Alan Brewer
Keyword(s):  
Wind Energy ◽  
Ground Level ◽  
Turbine Rotor ◽  
Energy Industry ◽  
Doppler Lidar ◽  
Near Surface ◽  
Surface Measurements ◽  
Wind Measurements ◽  
Upper Level ◽  
Insight Into

Addressing the need for high-quality wind information aloft in the layer occupied by turbine rotors (~30–150 m above ground level) is one of many significant challenges facing the wind energy industry. Without wind measurements at heights within the rotor sweep of the turbines, characteristics of the flow in this layer are unknown for wind energy and modeling purposes. Since flow in this layer is often decoupled from the surface, near-surface measurements are prone to errant extrapolation to these heights, and the behavior of the near-surface winds may not reflect that of the upper-level flow.

scholarly journals STRUCTURE OF TURBULENCE IN THE URBAN ATMOSPHERIC BOUNDARY LAYER DETECTED IN THE DOPPLER LIDAR OBSERVATION

2011 ◽  
Vol 67 (4) ◽  
pp. I_313-I_318 ◽  
Author(s):  
Ryoko ODA ◽  
Hironori IWAI ◽  
Shoken ISHII ◽  
Shinya SEKIZAWA ◽  
Kohei MIZUTANI ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Doppler Lidar ◽  
Lidar Observation

Retrieving Winds in the Surface Layer over Land Using an Airborne Doppler Lidar

2012 ◽  
Vol 29 (4) ◽  
pp. 487-499 ◽  
Author(s):  
K. S. Godwin ◽  
S. F. J. De Wekker ◽  
G. D. Emmitt
Keyword(s):  
Surface Wind ◽  
Surface Wind Speed ◽  
Lower Atmosphere ◽  
Doppler Lidar ◽  
Near Surface ◽  
Wind Retrieval ◽  
Wind Speed Maximum ◽  
Salinas Valley ◽  
Wind Retrievals ◽  
Wind Profiles

Abstract Airborne Doppler wind lidars are increasingly being used to measure winds in the lower atmosphere at higher spatial resolution than ever before. However, wind retrieval in the range gates closest to the earth’s surface remains problematic. When a laser beam from a nadir-pointing airborne Doppler wind lidar intercepts the ground, the return signal from the ground mixes with the windblown aerosol signal. As a result, winds in a layer adjacent to the surface are often unreliable and removed from wind profiles. This paper describes the problem in detail and discusses a two-step approach to improve near-surface wind retrievals. The two-step approach involves removing high-intensity ground returns and identifying and tracking aerosol radial velocities in the layer affected by ground interference. Using this approach, it is shown that additional range gates closer to the surface can be obtained, thereby further enhancing the potential of airborne Doppler lidar in atmospheric applications. The benefits of the two-step approach are demonstrated using measurements acquired over the Salinas Valley in central California. The additional range gates reveal details of the wind field that were previously not quantified with the original approach, such as a pronounced near-surface wind speed maximum.

scholarly journals Toward Improved Forecasts of Sea-Breeze Horizontal Convective Rolls at Super High Resolutions. Part II: The Impacts of Land Use and Buildings

2015 ◽  
Vol 143 (5) ◽  
pp. 1873-1894 ◽  
Author(s):  
Guixing Chen ◽  
Xinyue Zhu ◽  
Weiming Sha ◽  
Toshiki Iwasaki ◽  
Hiromu Seko ◽  
...  
Keyword(s):  
Land Use ◽  
Sea Breeze ◽  
Secondary Flows ◽  
Wake Flow ◽  
Near Surface ◽  
Sea Breezes ◽  
Regional Features ◽  
Secondary Circulations ◽  
Forecast Models ◽  
Convective Rolls

Abstract Horizontal convective rolls form in coastal areas around Sendai Airport during sea-breeze events. Using a building-resolving computational fluid dynamics model nested in an advanced forecast system with a data assimilation scheme, the authors perform a series of sensitivity experiments to investigate the impacts of land use and buildings on these rolls. The results show that the roll positions, intensities, and structures are significantly affected by variations in land use and the presence of buildings. Land-use heterogeneity is responsible for generating rolls with evident regional features. Major rolls tend to develop downwind of warm surfaces, and they dominate over neighboring rolls; thus, a heterogeneity-scale mode is imposed on the inherent roll wavelength. The roll’s rapid growth is attributable to warm surfaces that initiate a strong coupling among turbulent thermals, convective updrafts, pressure perturbations, and secondary flows in sea breezes. The heterogeneity-induced features differ considerably from the nearly homogeneous features that form over uniform surfaces. Additionally, the wake flow behind buildings helps organize near-surface warm air into streamwise bands that drive streaky ejections. The building-induced turbulence acts to modify secondary flows and displace roll updrafts toward building wakes. Such effects are most effective over villages with scattered houses that are aligned with the ambient wind. Building signatures are elongated in downwind open areas due to sustained secondary circulations. An analysis of turbulent kinetic energy shows that both land use and buildings regulate energy generation and transport, resulting in a clear response in roll growth. Thus, including complex surfaces in forecast models helps determine detailed characteristics and structures of roll convection over coastal regions.

Coherent Doppler lidar observation and numerical simulation of gap wind Kiyokawa-dashi in Japan

2006 ◽  
Author(s):  
K. Sasaki ◽  
S. Ishii ◽  
K. Mizutani ◽  
H. Kanno ◽  
D. Matsushima ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Doppler Lidar ◽  
Lidar Observation ◽  
Coherent Doppler Lidar

scholarly journals STRUCTURE OF STABLE NOCTURNAL BOUNDARY LAYER IN URBAN AREA DETECTED IN A DOPPLER LIDAR OBSERVATION

2012 ◽  
Vol 68 (4) ◽  
pp. I_1777-I_1782
Author(s):  
Ryoko ODA ◽  
Hironori IWAI ◽  
Atsushi INAGAKI ◽  
Shoken ISHII ◽  
Shinsuke SATOH ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Urban Area ◽  
Nocturnal Boundary Layer ◽  
Doppler Lidar ◽  
Lidar Observation

scholarly journals Structures of the Sea‐Breeze Front in Dual‐Doppler Lidar Observation and Coupled Mesoscale‐to‐LES Modeling

2019 ◽  
Vol 124 (5) ◽  
pp. 2397-2413 ◽  
Author(s):  
Guixing Chen ◽  
Hironori Iwai ◽  
Shoken Ishii ◽  
Kazuo Saito ◽  
Hiromu Seko ◽  
...  
Keyword(s):  
Sea Breeze ◽  
Doppler Lidar ◽  
Lidar Observation

Strong Updraft at a Sea-Breeze Front and Associated Vertical Transport of Near-Surface Dense Aerosol Observed by Doppler Lidar and Ceilometer

2011 ◽  
Vol 141 (1) ◽  
pp. 117-142 ◽  
Author(s):  
Hironori Iwai ◽  
Yasuhiro Murayama ◽  
Shoken Ishii ◽  
Kohei Mizutani ◽  
Yuichi Ohno ◽  
...  
Keyword(s):  
Sea Breeze ◽  
Vertical Transport ◽  
Doppler Lidar ◽  
Near Surface

scholarly journals Airport low-level wind shear lidar observation at beijing capital international airport

2018 ◽  
Vol 176 ◽  
pp. 06013
Author(s):  
Hongwei Zhang ◽  
Songhua Wu ◽  
Qichao Wang ◽  
Bingyi Liu ◽  
Xiaochun Zhai
Keyword(s):  
Wind Shear ◽  
Doppler Lidar ◽  
Low Level ◽  
Lidar Observation ◽  
International Airport ◽  
Glide Path ◽  
Coherent Doppler Lidar

Ocean University of China lidar team operated a pulse coherent Doppler lidar (PCDL) for the low level wind shear monitoring at the Beijing Capital International Airport (BCIA) in 2015. The experiment configuration, observation modes is presented. A case study shows that the low level wind shear events at the southern end of 18R/36L runway were mainly caused by the trees and buildings along the glide path under strong northwest wind conditions.

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