Assessment of the ERA-Interim Winds Using High-Altitude Stratospheric Balloons

Abstract This study focuses on the ability of ERA-Interim to represent wind variability in the middle atmosphere. The originality of the proposed approach is that wind measurements are deduced from the trajectories of zero-pressure balloons that can reach high-stratospheric altitudes. These balloons are mainly used to carry large scientific payloads. The trajectories of balloons launched above Esrange, Sweden, and Teresina, Brazil, from 2000 to 2011 were used to deduce zonal and meridional wind components (by considering the balloon as a perfect tracer at high altitude). Collected data cover several dynamical conditions associated with the winter and summer polar seasons and west and east phases of the quasi-biennial oscillation at the equator. Systematic comparisons between measurements and ERA-Interim data were performed for the two horizontal wind components, as well as wind speed and wind direction in the [100, 2]-hPa pressure range to deduce biases between the model and balloon measurements as a function of altitude. Results show that whatever the location and the geophysical conditions considered, biases between ERA-Interim and balloon wind measurements increase as a function of altitude. The standard deviation of the model–observation wind differences can attain more than 5 m s−1 at high altitude (pressure P < 20 hPa). A systematic ERA-Interim underestimation of the wind speed is observed and large biases are highlighted, especially for equatorial flights.

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Investigation of gravity waves using horizontally resolved radial velocity measurements

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-5795-2013 ◽

2013 ◽

Vol 6 (3) ◽

pp. 5795-5833 ◽

Cited By ~ 2

Author(s):

G. Stober ◽

S. Sommer ◽

M. Rapp ◽

R. Latteck

Keyword(s):

Gravity Wave ◽

Middle Atmosphere ◽

Beam Steering ◽

Detailed Comparison ◽

Atmospheric Model ◽

Meridional Wind ◽

Horizontal Wind ◽

Horizontal Structure ◽

Wind Variability ◽

Wave Parameters

Abstract. The Middle Atmosphere Alomar Radar System (MAARSY) on the island Andøya in Northern Norway (69.3° N, 16.0° E) observes polar mesospheric summer echoes (PMSE). These echoes are used as tracers of atmospheric dynamics to investigate the horizontal wind variability at high temporal and spatial resolution. MAARSY has the capability of a pulse-to-pulse beam steering allowing for systematic scanning experiments to study the horizontal structure of the backscatterers as well as to measure the radial velocities for each beam direction. Here we present a method to retrieve gravity wave parameters from these horizontally resolved radial wind variations by applying velocity azimuth display and volume velocity processing. Based on the observations a detailed comparison of the two wind analysis techniques is carried out in order to determine the zonal and meridional wind as well as to measure first order inhomogeneities. Further, we demonstrate the possibility to resolve the horizontal wave properties, e.g. horizontal wavelength, phase velocity and propagation direction. The robustness of the estimated gravity wave parameters is tested by a simple atmospheric model.

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Investigation of gravity waves using horizontally resolved radial velocity measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-6-2893-2013 ◽

2013 ◽

Vol 6 (10) ◽

pp. 2893-2905 ◽

Cited By ~ 24

Author(s):

G. Stober ◽

S. Sommer ◽

M. Rapp ◽

R. Latteck

Keyword(s):

Gravity Wave ◽

Middle Atmosphere ◽

Beam Steering ◽

Detailed Comparison ◽

Atmospheric Model ◽

Meridional Wind ◽

Horizontal Wind ◽

Horizontal Structure ◽

Wind Variability ◽

Wave Parameters

Abstract. The Middle Atmosphere Alomar Radar System (MAARSY) on the island of Andøya in Northern Norway (69.3° N, 16.0° E) observes polar mesospheric summer echoes (PMSE). These echoes are used as tracers of atmospheric dynamics to investigate the horizontal wind variability at high temporal and spatial resolution. MAARSY has the capability of pulse-to-pulse beam steering allowing for systematic scanning experiments to study the horizontal structure of the backscatterers as well as to measure the radial velocities for each beam direction. Here we present a method to retrieve gravity wave parameters from these horizontally resolved radial wind variations by applying velocity azimuth display and volume velocity processing. Based on the observations a detailed comparison of the two wind analysis techniques is carried out in order to determine the zonal and meridional wind as well as to measure first-order inhomogeneities. Further, we demonstrate the possibility to resolve the horizontal wave properties, e.g., horizontal wavelength, phase velocity and propagation direction. The robustness of the estimated gravity wave parameters is tested by a simple atmospheric model.

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Winds in the Lower Cloud Level on the Nightside of Venus from VIRTIS-M (Venus Express) 1.74 μm Images

Atmosphere ◽

10.3390/atmos12020186 ◽

2021 ◽

Vol 12 (2) ◽

pp. 186

Author(s):

Dmitry A. Gorinov ◽

Ludmila V. Zasova ◽

Igor V. Khatuntsev ◽

Marina V. Patsaeva ◽

Alexander V. Turin

Keyword(s):

Wind Speed ◽

Meridional Wind ◽

Equatorial Region ◽

Hadley Cell ◽

Horizontal Wind ◽

Simultaneous Increase ◽

Volcanic Area ◽

Infrared Thermal Imaging ◽

Latitude Range ◽

Lower Cloud

The horizontal wind velocity vectors at the lower cloud layer were retrieved by tracking the displacement of cloud features using the 1.74 µm images of the full Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS-M) dataset. This layer was found to be in a superrotation mode with a westward mean speed of 60–63 m s−1 in the latitude range of 0–60° S, with a 1–5 m s−1 westward deceleration across the nightside. Meridional motion is significantly weaker, at 0–2 m s−1; it is equatorward at latitudes higher than 20° S, and changes its direction to poleward in the equatorial region with a simultaneous increase of wind speed. It was assumed that higher levels of the atmosphere are traced in the equatorial region and a fragment of the poleward branch of the direct lower cloud Hadley cell is observed. The fragment of the equatorward branch reveals itself in the middle latitudes. A diurnal variation of the meridional wind speed was found, as east of 21 h local time, the direction changes from equatorward to poleward in latitudes lower than 20° S. Significant correlation with surface topography was not found, except for a slight decrease of zonal wind speed, which was connected to the volcanic area of Imdr Regio.

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Characteristics of Stratospheric Winds over Jiuquan (41.1°N, 100.2°E) Using Rocketsonde Data in 1967–2004

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-16-0014.1 ◽

2017 ◽

Vol 34 (3) ◽

pp. 657-667 ◽

Cited By ~ 2

Author(s):

Z. Sheng ◽

J. W. Li ◽

Y. Jiang ◽

S. D. Zhou ◽

W. L. Shi

Keyword(s):

Zonal Wind ◽

Middle Atmosphere ◽

Correlation Coefficients ◽

Meridional Wind ◽

Horizontal Wind ◽

Cycle Period ◽

Observation Data ◽

Wind Fields ◽

Zonal Winds ◽

Model Research

AbstractStratospheric winds play a significant role in middle atmosphere dynamics, model research, and carrier rocket experiments. For the first time, 65 sets of rocket sounding experiments conducted at Jiuquan (41.1°N, 100.2°E), China, from 1967 to 2004 are presented to study horizontal wind fields in the stratosphere. At a fixed height, wind speed obeys the lognormal distribution. Seasonal mean winds are westerly in winter and easterly in summer. In spring and autumn, zonal wind directions change from the upper to the lower stratosphere. The monthly zonal mean winds have an annual cycle period with large amplitudes at high altitudes. The correlation coefficients for zonal winds between observations and the Horizontal Wind Model (HWM) with all datasets are 0.7. The MERRA reanalysis is in good agreement with rocketsonde data according to the zonal winds comparison with a coefficient of 0.98. The sudden stratospheric warming is an important contribution to biases in the HWM, because it changes the zonal wind direction in the midlatitudes. Both the model and the reanalysis show dramatic meridional wind differences with the observation data.

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Doppler wind lidar activities at Cabauw

10.5194/ems2021-136 ◽

2021 ◽

Author(s):

Steven Knoop ◽

Fred Bosveld ◽

Marijn de Haij ◽

Arnoud Apituley

Keyword(s):

Wind Speed ◽

Wind Profile ◽

Continuous Wave ◽

Wind Farms ◽

Data Availability ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Low Clouds ◽

Wind Measurements ◽

Wind Lidar

Atmospheric motion and turbulence are essential parameters for weather and topics related to air quality. Therefore, wind profile measurements play an important role in atmospheric research and meteorology. One source of wind profile data are Doppler wind lidars, which are laser-based remote sensing instruments that measure wind speed and wind direction up to a few hundred meters or even a few kilometers. Commercial wind lidars use the laser wavelength of 1.5 &#181;m and therefore backscatter is mainly from aerosols while clear air backscatter is minimal, limiting the range to the boundary layer typically.We have carried out a two-year intercomparison of the ZephIR 300M (ZX Lidars) short-range wind lidar and tall mast wind measurements at Cabauw [1]. We have focused on the (height-dependent) data availability of the wind lidar under various meteorological conditions and the data quality through a comparison with in situ wind measurements at several levels in the 213m tall meteorological mast. We have found an overall availability of quality-controlled wind lidar data of 97% to 98 %, where the missing part is mainly due to precipitation events exceeding 1 mm/h or fog or low clouds below 100 m. The mean bias in the horizontal wind speed is within 0.1 m/s with a high correlation between the mast and wind lidar measurements, although under some specific conditions (very high wind speed, fog or low clouds) larger deviations are observed. This instrument is being deployed within North Sea wind farms.Recently, a scanning long-range wind lidar Windcube 200S (Leosphere/Vaisala) has been installed at Cabauw, as part of the Ruisdael Observatory program [2]. The scanning Doppler wind lidars will provide detailed measurements of the wind field, aerosols and clouds around the Cabauw site, in coordination with other instruments, such as the cloud radar.[1] Knoop, S., Bosveld, F. C., de Haij, M. J., and Apituley, A.: A 2-year intercomparison of continuous-wave focusing wind lidar and tall mast wind measurements at Cabauw, Atmos. Meas. Tech., 14, 2219&#8211;2235, 2021[2] https://ruisdael-observatory.nl/

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Development of an in situ Acoustic Anemometer to Measure Wind in the Stratosphere for SENSOR

10.5194/amt-2021-76 ◽

2021 ◽

Author(s):

Song Liang ◽

Hu Xiong ◽

Wei Feng ◽

Yan Zhaoai ◽

Xu Qingchen ◽

...

Keyword(s):

Wind Speed ◽

Meridional Wind ◽

Floating Platform ◽

Level Flight ◽

Subsequent Publication ◽

Wind Measurements ◽

Commercial Off The Shelf ◽

Solar Storms ◽

Acoustic Anemometer

Abstract. The Stratospheric Environmental respoNses to Solar stORms (SENSOR) campaign investigates the influence of solar storms on the stratosphere. This campaign employs a long-duration zero-pressure balloon as a platform to carry multiple types of payloads during a series of flight experiments in the mid-latitude stratosphere from 2019 to 2022. This article describes the development and testing of an acoustic anemometer for obtaining in situ wind measurements along the balloon trajectory. Developing this anemometer was necessary, as there is no existing commercial off-the-shelf product, to the authors' knowledge, capable of obtaining in situ wind measurements on a high-altitude balloon or other similar floating platform in the stratosphere. The anemometer is also equipped with temperature, pressure, and humidity sensors from a Temperature-Pressure-Humidity measurement module, inherited from a radiosonde developed for sounding balloons. The acoustic anemometer and other sensors were used in a flight experiment of the SENSOR campaign that took place in the Da chaidan District (95.37° E, 37.74° N) on 4 September 2019. The zonal and meridional wind speed observations, which were obtained during level flight at an altitude exceeding 20 km, are presented. This is the first time that in situ wind measurements were obtained during level flight at this altitude. In addition to wind speed measurements, temperature, pressure, and relative humidity measurements during ascent are compared to observations from a nearby radiosonde launched four hours earlier. Further analysis of the wind data will presented in a subsequent publication. The problems experienced by the acoustic anemometer during the 2019 experiment show that the acoustic anemometer must be improved for future experiments in the SENSOR campaign.

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Influence of the Stratospheric Quasi-Biennial Oscillation on the Madden–Julian Oscillation during Austral Summer

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-16-0205.1 ◽

2017 ◽

Vol 74 (4) ◽

pp. 1105-1125 ◽

Cited By ~ 44

Author(s):

Eriko Nishimoto ◽

Shigeo Yoden

Keyword(s):

Large Scale ◽

Statistical Significance ◽

Austral Summer ◽

Horizontal Wind ◽

Convective System ◽

Madden Julian Oscillation ◽

Quasi Biennial Oscillation ◽

Enso Events ◽

Convective Region ◽

Biennial Oscillation

Abstract Influence of the stratospheric quasi-biennial oscillation (QBO) on the Madden–Julian oscillation (MJO) and its statistical significance are examined for austral summer (DJF) in neutral ENSO events during 1979–2013. The amplitude of the OLR-based MJO index (OMI) is typically larger in the easterly phase of the QBO at 50 hPa (E-QBO phase) than in the westerly (W-QBO) phase. Daily composite analyses are performed by focusing on phase 4 of the OMI, when the active convective system is located over the eastern Indian Ocean through the Maritime Continent. The composite OLR anomaly shows a larger negative value and slower eastward propagation with a prolonged period of active convection in the E-QBO phase than in the W-QBO phase. Statistically significant differences of the MJO activities between the QBO phases also exist with dynamical consistency in the divergence of horizontal wind, the vertical wind, the moisture, the precipitation, and the 100-hPa temperature. A conditional sampling analysis is also performed by focusing on the most active convective region for each day, irrespective of the MJO amplitude and phase. Composite vertical profiles of the conditionally sampled data over the most active convective region reveal lower temperature and static stability around the tropopause in the E-QBO phase than in the W-QBO phase, which indicates more favorable conditions for developing deep convection. This feature is more prominent and extends into lower levels in the upper troposphere over the most active convective region than other tropical regions. Composite longitude–height sections show similar features of the large-scale convective system associated with the MJO, including a vertically propagating Kelvin response.

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Dynamics of the Disrupted 2015/16 Quasi-Biennial Oscillation

Journal of Climate ◽

10.1175/jcli-d-16-0663.1 ◽

2017 ◽

Vol 30 (15) ◽

pp. 5661-5674 ◽

Cited By ~ 29

Author(s):

Lawrence Coy ◽

Paul A. Newman ◽

Steven Pawson ◽

Leslie R. Lait

Keyword(s):

Lower Stratosphere ◽

Global Climate ◽

Quasi Biennial Oscillation ◽

Wave Forcing ◽

Wind Variability ◽

Momentum Fluxes ◽

Horizontal Momentum ◽

The Tropics ◽

Global Reanalysis ◽

Biennial Oscillation

A significant disruption of the quasi-biennial oscillation (QBO) occurred during the Northern Hemisphere (NH) winter of 2015/16. Since the QBO is the major wind variability source in the tropical lower stratosphere and influences the rate of ascent of air entering the stratosphere, understanding the cause of this singular disruption may provide new insights into the variability and sensitivity of the global climate system. Here this disruptive event is examined using global reanalysis winds and temperatures from 1980 to 2016. Results reveal record maxima in tropical horizontal momentum fluxes and wave forcing of the tropical zonal mean zonal wind over the NH 2015/16 winter. The Rossby waves responsible for these record tropical values appear to originate in the NH and were focused strongly into the tropics at the 40-hPa level. Two additional NH winters, 1987/88 and 2010/11, were also found to have large tropical lower-stratospheric momentum flux divergences; however, the QBO westerlies did not change to easterlies in those cases.

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Coastal Wind Measurements Using a Single Scanning LiDAR

Remote Sensing ◽

10.3390/rs12081347 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1347 ◽

Cited By ~ 4

Author(s):

Susumu Shimada ◽

Jay Prakash Goit ◽

Teruo Ohsawa ◽

Tetsuya Kogaki ◽

Satoshi Nakamura

Keyword(s):

Wind Speed ◽

Goodness Of Fit ◽

Sonic Anemometer ◽

Data Availability ◽

Horizontal Wind ◽

Research Station ◽

Lidar Measurement ◽

Wind Speeds ◽

Wind Measurements ◽

Scanning Lidar

A wind measurement campaign using a single scanning light detection and ranging (LiDAR) device was conducted at the Hazaki Oceanographical Research Station (HORS) on the Hazaki coast of Japan to evaluate the performance of the device for coastal wind measurements. The scanning LiDAR was deployed on the landward end of the HORS pier. We compared the wind speed and direction data recorded by the scanning LiDAR to the observations obtained from a vertical profiling LiDAR installed at the opposite end of the pier, 400 m from the scanning LiDAR. The best practice for offshore wind measurements using a single scanning LiDAR was evaluated by comparing results from a total of nine experiments using several different scanning settings. A two-parameter velocity volume processing (VVP) method was employed to retrieve the horizontal wind speed and direction from the radial wind speed. Our experiment showed that, at the current offshore site with a negligibly small vertical wind speed component, the accuracy of the scanning LiDAR wind speeds and directions was sensitive to the azimuth angle setting, but not to the elevation angle setting. In addition to the validations for the 10-minute mean wind speeds and directions, the application of LiDARs for the measurement of the turbulence intensity (TI) was also discussed by comparing the results with observations obtained from a sonic anemometer, mounted at the seaward end of the HORS pier, 400 m from the scanning LiDAR. The standard deviation obtained from the scanning LiDAR measurement showed a greater fluctuation than that obtained from the sonic anemometer measurement. However, the difference between the scanning LiDAR and sonic measurements appeared to be within an acceptable range for the wind turbine design. We discuss the variations in data availability and accuracy based on an analysis of the carrier-to-noise ratio (CNR) distribution and the goodness of fit for curve fitting via the VVP method.

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The stratospheric quasi-biennial oscillation observed in the semidiurnal ground pressure data

Annales Geophysicae ◽

10.1007/s00585-995-0740-5 ◽

1995 ◽

Vol 13 (7) ◽

pp. 740-744 ◽

Cited By ~ 6

Author(s):

H. Teitelbaum ◽

F. Vial ◽

P. Bauer

Keyword(s):

Time Series ◽

Pressure Measurements ◽

Pressure Data ◽

Quasi Biennial Oscillation ◽

Ground Pressure ◽

Trace Back ◽

Stratospheric Balloon ◽

Highly Correlated ◽

Biennial Oscillation ◽

Balloon Measurements

Abstract. Ground pressure observations made at Macao (22°N, 113°E) from 1953 to 1991 are analyzed and compared with the stratospheric quasi-biennial oscillation (QBO) data obtained during the same interval. The periods of the two phenomena and their time evolution are found to be close to each other. Furthermore, the time series of the stratospheric winds and the S2(p) QBO signature are highly correlated, thus confirming earlier analysis. On this basis, pressure measurements obtained at Batavia (now Djakarta: 6°S, 107°E) from 1870 to 1944 are used to trace back the QBO phenomenon before the advent of systematic stratospheric balloon measurements. The inferred period, which varies between 25 and 32 months, suggests that the QBO has been present in the atmosphere at least since 1870.

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