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

First Doppler lidar and cloud radar measurements of orographic convection initiation from a mountain observatory in the Al Hajar Mountains of the United Arab Emirates.

2021 ◽  
Author(s):  
Oliver Branch ◽  
Andreas Behrendt ◽  
Osama Alnayef ◽  
Florian Späth ◽  
Thomas Schwitalla ◽  
...  
Keyword(s):  
United Arab Emirates ◽  
Sea Breeze ◽  
Doppler Lidar ◽  
Cloud Seeding ◽  
Low Level ◽  
Cloud Radar ◽  
Orographic Convection ◽  
Radar Measurements ◽  
Convection Initiation ◽  
Convective Cells

<p>We present exciting Doppler lidar and cloud radar measurements from a high-vantage mountain observatory in the hyper-arid United Arab Emirates (UAE) - initiated as part of the UAE Research Program for Rain Enhancement Science (UAEREP). The observatory was designed to study the clear-air pre-convective environment and subsequent convective events in the arid Al Hajar Mountains, with the overarching goal of improving understanding and nowcasting of seedable orographic clouds. During summer in the Al Hajar Mountains (June to September), weather processes are often complex, with summer convection being initiated by several phenomena acting in concert, e.g., interaction between sea breeze and horizontal convective rolls. These interactions can combine to initiate sporadic convective storms and these can be intense enough to cause flash floods and erosion. Such events here are influenced by mesoscale phenomena like the low-level jet and local sea breeze, and are constrained by larger-scale synoptic conditions.</p><p>The Doppler lidar and cloud radar were employed for approximately two years at a high vantage-point to capture valley wind flows and observe convective cells. The instruments were configured to run synchronized polar (PPI) scans at 0°, 5°, and 45° elevation angles and vertical cross-section (RHI) scans at 0°, 30°, 60, 90°, 120°, and 150° azimuth angles. Using this imagery, along with local C-band radar and satellite data, we were able to identify and analyze several convective cases. To illustrate our results, we have selected two cases under unstable conditions - the 5 and 6 September 2018. In both cases, we observed areas of low-level convergence/divergence, particularly associated with wind flow around a peak 2 km to the south-west of the observatory. The extension of these deformations are visible in the atmosphere to a height of 3 km above sea level. Subsequently, we observed convective cells developing at those approximate locations – apparently initiated because of these phenomena. The cloud radar images provided detailed observations of cloud structure, evolution, and precipitation. In both convective cases, pre-convective signatures were apparent before CI, in the form of convergence, wind shear structures, and updrafts.</p><p>These results have demonstrated the value of synergetic observations for understanding orographic convection initiation, improvement of forecast models, and cloud seeding guidance. The manuscript based on these results is now the subject of a peer review (Branch et al., 2021).</p><p> </p><p>Branch, O., Behrendt, Andreas Alnayef, O., Späth, F., Schwitalla, Thomas, Temimi, M., Weston, M., Farrah, S., Al Yazeedi, O., Tampi, S., Waal, K. de and Wulfmeyer, V.: The new Mountain Observatory of the Project “Optimizing Cloud Seeding by Advanced Remote Sensing and Land Cover Modification (OCAL)” in the United Arab Emirates: First results on Convection Initiation, J. Geophys. Res.  Atmos., 2021. In review (submitted 23.11.2020).</p>

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

Evolution of the Monterey Bay Sea-Breeze Layer As Observed by Pulsed Doppler Lidar

1993 ◽  
Vol 50 (24) ◽  
pp. 3959-3982 ◽  
Author(s):  
Robert M. Banta ◽  
Lisa D. Olivier ◽  
David H. Levinson
Keyword(s):  
Sea Breeze ◽  
Monterey Bay ◽  
Doppler Lidar ◽  
Pulsed Doppler

The Land/Sea Breeze Experiment (LASBEX)

1990 ◽  
Vol 71 (5) ◽  
pp. 656-664 ◽  
Author(s):  
J. M. Intrieri ◽  
C. G. Little ◽  
W. J. Shaw ◽  
R. M. Banta ◽  
P. A. Durkee ◽  
...  
Keyword(s):  
Vertical Structure ◽  
Sea Breeze ◽  
Triangular Array ◽  
Land Breeze ◽  
Doppler Lidar ◽  
Preliminary Results ◽  
Surface Weather ◽  
Weather Stations ◽  
Observing Systems

The Land/Sea Breeze Experiment (LASBEX) was conducted at Moss Landing, California, 15–30 September 1987. The experiment was designed to study the vertical structure and mesoscale variation of the land/sea breeze. A Doppler lidar, a triangular array of three sodars, two sounding systems (one deployed from land and one from a ship), and six surface weather stations (one shipborne) were sited around the Moss Landing area. Measurements obtained included ten sea-breeze and four land-breeze events. This paper describes the objectives and design of the experiment, as well as the observing systems that were used. Some preliminary results and selected observations are presented, called from the data collected, as well as the ensuing analysis plans.

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

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 Variability of three-dimensional sea breeze structure in southern France: observations and evaluation of empirical scaling laws

2006 ◽  
Vol 24 (7) ◽  
pp. 1783-1799 ◽  
Author(s):  
P. Drobinski ◽  
S. Bastin ◽  
A. Dabas ◽  
P. Delville ◽  
O. Reitebuch
Keyword(s):  
Scaling Laws ◽  
Three Dimensional ◽  
Surface Friction ◽  
Sea Breeze ◽  
Return Flow ◽  
Doppler Lidar ◽  
Breeze Circulation ◽  
Southern France ◽  
Surface Station ◽  
The Impact

Abstract. Sea-breeze dynamics in southern France is investigated using an airborne Doppler lidar, a meteorological surface station network and radiosoundings, in the framework of the ESCOMPTE experiment conducted during summer 2001 in order to evaluate the role of thermal circulations on pollutant transport and ventilation. The airborne Doppler lidar WIND contributed to three-dimensional (3-D) mapping of the sea breeze circulation in an unprecedented way. The data allow access to the onshore and offshore sea breeze extents (xsb), and to the sea breeze depth (zsb) and intensity (usb). They also show that the return flow of the sea breeze circulation is very seldom seen in this area due to (i) the presence of a systematic non zero background wind, and (ii) the 3-D structure of the sea breeze caused by the complex coastline shape and topography. A thorough analysis is conducted on the impact of the two main valleys (Rhône and Durance valleys) affecting the sea breeze circulation in the area. Finally, this dataset also allows an evaluation of the existing scaling laws used to derive the sea breeze intensity, depth and horizontal extent. The main results of this study are that (i) latitude, cumulative heating and surface friction are key parameters of the sea breeze dynamics; (ii) in presence of strong synoptic flow, all scaling laws fail in predicting the sea breeze characteristics (the sea breeze depth, however being the most accurately predicted); and (iii) the ratio zsb/usb is approximately constant in the sea breeze flow.

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