scholarly journals Referee Comments on "High resolution humidity profiles retrieved from wind profiler radar measurements"

2017 ◽  
Author(s):  
Anonymous
Keyword(s):  
High Resolution ◽  
Wind Profiler ◽  
Wind Profiler Radar ◽  
Radar Measurements ◽  
Humidity Profiles

scholarly journals High-resolution humidity profiles retrieved from wind profiler radar measurements

2018 ◽  
Vol 11 (3) ◽  
pp. 1669-1688
Author(s):  
Frédérique Saïd ◽  
Bernard Campistron ◽  
Paolo Di Girolamo
Keyword(s):  
Boundary Layer ◽  
Specific Humidity ◽  
Wind Profiler ◽  
Raman Lidar ◽  
Humidity Profile ◽  
The Past ◽  
Wind Profiler Radar ◽  
Radar Measurements ◽  
Humidity Profiles ◽  
Calibration Coefficients

Abstract. The retrieval of humidity profiles from wind profiler radars has already been documented in the past 30 years and is known to be neither as straightforward and nor as robust as the retrieval of the wind velocity. The main constraint to retrieve the humidity profile is the necessity to combine measurements from the wind profiler and additional measurements (such as observations from radiosoundings at a coarser time resolution). Furthermore, the method relies on some assumptions and simplifications that restrict the scope of its application. The first objective of this paper is to identify the obstacles and limitations and solve them, or at least define the field of applicability. To improve the method, we propose using the radar capacity to detect transition levels, such as the top level of the boundary layer, marked by a maximum in the radar reflectivity. This forces the humidity profile from the free troposphere and from the boundary layer to coincide at this level, after an optimization of the calibration coefficients, and reduces the error. The resulting mean bias affecting the specific humidity profile never exceeds 0.25 g kg−1. The second objective is to explore the capability of the algorithm to retrieve the humidity vertical profiles for an operational purpose by comparing the results with observations from a Raman lidar.

Combining Microwave Radiometer and Wind Profiler Radar Measurements for High-Resolution Atmospheric Humidity Profiling

2005 ◽  
Vol 22 (7) ◽  
pp. 949-965 ◽  
Author(s):  
Laura Bianco ◽  
Domenico Cimini ◽  
Frank S. Marzano ◽  
Randolph Ware
Keyword(s):  
High Resolution ◽  
Microwave Radiometer ◽  
Potential Temperature ◽  
Physical Method ◽  
Wind Profiler ◽  
Tropospheric Temperature ◽  
Atmospheric Humidity ◽  
Wind Profiler Radar ◽  
Combined Algorithm ◽  
Humidity Profiles

Abstract A self-consistent remote sensing physical method to retrieve atmospheric humidity high-resolution profiles by synergetic use of a microwave radiometer profiler (MWRP) and wind profiler radar (WPR) is illustrated. The proposed technique is based on the processing of WPR data for estimating the potential refractivity gradient profiles and their optimal combination with MWRP estimates of potential temperature profiles in order to fully retrieve humidity gradient profiles. The combined algorithm makes use of recent developments in WPR signal processing, computing the zeroth-, first-, and second-order moments of WPR Doppler spectra via a fuzzy logic method, which provides quality control of radar data in the spectral domain. On the other hand, the application of neural network to brightness temperatures, measured by a multichannel MWRP, can provide continuous estimates of tropospheric temperature and humidity profiles. Performance of the combined algorithm in retrieving humidity profiles is compared with simultaneous in situ radiosonde observations (raob’s). The empirical sets of WPR and MWRP data were collected at the Atmospheric Radiation Measurement (ARM) Program’s Southern Great Plains (SGP) site. Combined microwave radiometer and wind profiler measurements show encouraging results and significantly improve the spatial vertical resolution of atmospheric humidity profiles. Finally, some of the limitations found in the use of this technique and possible future improvements are also discussed.

scholarly journals High resolution humidity profiles retrieved from wind profiler radar measurements

2017 ◽  
Author(s):  
Frédérique Saïd ◽  
Bernard Campistron ◽  
Paolo Di Girolamo
Keyword(s):  
Boundary Layer ◽  
Water Vapor ◽  
Wind Profiler ◽  
Major Advance ◽  
Vertical Profiles ◽  
Mixing Ratio ◽  
Wind Profiler Radar ◽  
Radar Measurements ◽  
Water Vapor Mixing Ratio ◽  
Calibration Coefficients

Abstract. Vertical profiles of the atmospheric water vapor mixing ratio are retrieved with an algorithm based on the combination of measurements from an Ultra High Frequency-band wind profiler and radiosoundings at a coarser time resolution. The major advance with respect to previous works is the use of the radar capacity to detect transition levels, such as the top level of the boundary layer, marked by a maximum in the radar reflectivity. This forces the water vapor mixing ratio profile from the free troposphere and from the boundary layer to coincide at this level, after an optimization of the calibration coefficients. The capability of the algorithm to retrieve the humidity vertical profiles for an operational purpose is explored and the results are compared with observations from a Raman lidar.

scholarly journals Aspects of quality control of wind profiler measurements in complex topography

2014 ◽  
Vol 7 (1) ◽  
pp. 135-148 ◽  
Author(s):  
M. Maruri ◽  
J. A. Romo ◽  
L. Gomez
Keyword(s):  
Complex Terrain ◽  
Meteorological Conditions ◽  
Complex Signal ◽  
Wind Profiler ◽  
Complex Topography ◽  
Homogeneity Study ◽  
Homogeneity Assumption ◽  
Patterns Of Behavior ◽  
Wind Profiler Radar ◽  
Wind Profiles

Abstract. It is well known in the scientific community that some remote sensing instruments assume that sample volumes present homogeneous conditions within a defined meteorological profile. At complex topographic sites and under extreme meteorological conditions, this assumption may be fallible depending on the site, and it is more likely to fail in the lower layers of the atmosphere. This piece of work tests the homogeneity of the wind field over a boundary layer wind profiler radar located in complex terrain on the coast under different meteorological conditions. The results reveal the qualitative importance of being aware of deviations in this homogeneity assumption and evaluate its effect on the final product. Patterns of behavior in data have been identified in order to simplify the analysis of the complex signal registered. The quality information obtained from the homogeneity study under different meteorological conditions provides useful indicators for the best alternatives the system can offer to build wind profiles. Finally, the results are also to be considered in order to integrate them in a quality algorithm implemented at the product level.

scholarly journals Lower Atmospheric Wind Dynamics as Measured by the 1290 MHz Wind Profiler Radar Located at Cardington (Lat. 52.10ºN, Long. 0.42ºE), UK and Their Comparisons with Near-by Radiosonde Instrument

2020 ◽  
pp. 22-35
Author(s):  
M. Satyavani ◽  
P. S. Brahmanandam ◽  
P. S. V. Subba Rao ◽  
M. P. Rao
Keyword(s):  
Remote Sensing ◽  
Boundary Layer ◽  
Wind Speed ◽  
Universal Time ◽  
Diurnal Variations ◽  
Wind Profiler ◽  
Independent Observations ◽  
Wind Profiler Radar

This study reports diurnal variations of wind directions, wind speed of vector winds, and the evolution of boundary layer (BL) over a mid-latitude measured using a transportable 1290 MHz wind profiling radar located at Cardington (Lat. 52.10ºN; Long. 0.42ºE), Bedfordshire, UK from 17 to 28 April 2010. The horizontal winds show benign behavior during nighttime hours, while winds during daytime hours had magnitudes around, on average, 10-20 m/s, in the majority of the cases. The heights of the boundary layer (BL) varied from as low as ~1100 m to ~2600 km and BL height had shown to have evolved from 0700 universal time (UT) onwards and collapsed by 0000 UT.  Besides, a comparison made between winds measured by the 1290 MHz radar and near-by radiosonde showed a moderate similitude between them, albeit a few discrepancies are found in wind directions and speeds. The possible reasons for these discrepancies could be different volume sensing of observations of these independent observations. An attempt is, therefore, made to calculate radiosonde balloon drifts [1] for the ascending node of the balloons, which had confirmed that the balloons often drifted horizontally as long as up to 100 km. The large drifts, most probably, are the possible reasons for the mismatching of winds measured by these two independent remote sensing instruments.

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