GPS calibrated multiwavelength water vapor Raman lidar measurements to assess urban aerosol hygroscopicity

Abstract. This study focuses on the analysis of aerosol hygroscopicity using remote sensing technique. Continuous observations of aerosol backscatter coefficient, temperature and water vapour mixing ratio are performed by means of a Raman lidar system at the aerological station of MeteoSwiss at Payerne (Switzerland) since 2008. These measurements allow us to monitor in a continuous way any change of aerosol properties as a function of the relative humidity (RH). These changes can be observed either in time at constant altitude or in altitude at a constant time. The accuracy and precision of RH measurements from the lidar have been evaluated using the radiosonde (RS) technique as reference. A total of 172 RSs were used in this intercomparison which revealed a small bias (

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Raman lidar measurements of water vapor as ground-truth for passive remote sensors

Conference Proceedings Second Topical Symposium on Combined Optical-Microwave Earth and Atmosphere Sensing ◽

10.1109/comeas.1995.472320 ◽

1995 ◽

Author(s):

S.H. Melfi ◽

D. Whiteman ◽

R. Ferrare ◽

K. Evans

Keyword(s):

Water Vapor ◽

Ground Truth ◽

Raman Lidar ◽

Remote Sensors ◽

Lidar Measurements

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Airborne DIAL and ground-based Raman lidar measurements of water vapor over the Southern Great Plains

10.1117/12.509615 ◽

2003 ◽

Author(s):

Richard A. Ferrare ◽

Edward V. Browell ◽

Syed Ismail ◽

Susan Kooi ◽

Vince G. Brackett ◽

...

Keyword(s):

Water Vapor ◽

Great Plains ◽

Raman Lidar ◽

Southern Great Plains ◽

Lidar Measurements

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First-Year Operation of a New Water Vapor Raman Lidar at the JPL Table Mountain Facility, California

Journal of Atmospheric and Oceanic Technology ◽

10.1175/2007jtecha978.1 ◽

2008 ◽

Vol 25 (8) ◽

pp. 1454-1462 ◽

Cited By ~ 26

Author(s):

Thierry Leblanc ◽

I. Stuart McDermid ◽

Robin A. Aspey

Keyword(s):

Water Vapor ◽

Current System ◽

First Year ◽

Raman Lidar ◽

Upper Troposphere ◽

Mixing Ratios ◽

Table Mountain ◽

Lidar Measurements ◽

Better Than ◽

Good Agreement

Abstract A new water vapor Raman lidar was recently built at the Table Mountain Facility (TMF) of the Jet Propulsion Laboratory (JPL) in California and more than a year of routine 2-h-long nighttime measurements 4–5 times per week have been completed. The lidar was designed to reach accuracies better than 5% anywhere up to 12-km altitude, and with the capability to measure water vapor mixing ratios as low as 1 to 10 ppmv near the tropopause and in the lower stratosphere. The current system is not yet fully optimized but has already shown promising results as water vapor profiles have been retrieved up to 18-km altitude. Comparisons with Vaisala RS92K radiosondes exhibit very good agreement up to at least 10 km. They also revealed a wet bias in the lidar profiles (or a dry bias in the radiosonde profiles), increasing with altitude and becoming significant near 10 km and large when approaching the tropopause. This bias cannot be explained solely by well-known too-dry measurements of the RS92K in the upper troposphere and therefore must partly originate in the lidar measurements. Excess signal due to residual fluorescence in the lidar receiver components is among the most likely candidates and is subject to ongoing investigation.

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Ground-based water vapor raman lidar measurements up to the upper troposphere and lower stratosphere for long-term monitoring

Atmospheric Measurement Techniques ◽

10.5194/amt-5-17-2012 ◽

2012 ◽

Vol 5 (1) ◽

pp. 17-36 ◽

Cited By ~ 43

Author(s):

T. Leblanc ◽

I. S. McDermid ◽

T. D. Walsh

Keyword(s):

Water Vapor ◽

Lower Stratosphere ◽

Lower Troposphere ◽

Atmospheric Composition ◽

Raman Lidar ◽

Upper Troposphere ◽

Lidar Measurements ◽

Development Data ◽

Instrumental Development

Abstract. Recognizing the importance of water vapor in the upper troposphere and lower stratosphere (UTLS) and the scarcity of high-quality, long-term measurements, JPL began the development of a powerful Raman lidar in 2005 to try to meet these needs. This development was endorsed by the Network for the Detection of Atmospheric Composition Change (NDACC) and the validation program for the EOS-Aura satellite. In this paper we review the stages in the instrumental development, data acquisition and analysis, profile retrieval and calibration procedures of the lidar, as well as selected results from three validation campaigns: MOHAVE (Measurements of Humidity in the Atmosphere and Validation Experiments), MOHAVE-II, and MOHAVE 2009. In particular, one critical result from this latest campaign is the very good agreement (well below the reported uncertainties) observed between the lidar and the Cryogenic Frost-Point Hygrometer in the entire lidar range 3–20 km, with a mean bias not exceeding 2% (lidar dry) in the lower troposphere, and 3% (lidar moist) in the UTLS. Ultimately the lidar has demonstrated capability to measure water vapor profiles from ∼1 km above the ground to the lower stratosphere with a precision of 10% or better near 13 km and below, and an estimated accuracy of 5%. Since 2005, nearly 1000 profiles have been routinely measured, and since 2009, the profiles have typically reached 14 km for one-hour integration times and 1.5 km vertical resolution, and can reach 21 km for 6-h integration times using degraded vertical resolutions. These performance figures show that, with our present target of routinely running our lidar two hours per night, 4 nights per week, we can achieve measurements with a precision in the UTLS equivalent to that achieved if launching one CFH per month.

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Raman lidar measurements of water vapor and cirrus clouds during the passage of Hurricane Bonnie

Journal of Geophysical Research Atmospheres ◽

10.1029/2000jd900621 ◽

2001 ◽

Vol 106 (D6) ◽

pp. 5211-5225 ◽

Cited By ~ 43

Author(s):

D. N. Whiteman ◽

K. D. Evans ◽

B. Demoz ◽

D. O'C. Starr ◽

E. W. Eloranta ◽

...

Keyword(s):

Water Vapor ◽

Cirrus Clouds ◽

Raman Lidar ◽

Lidar Measurements ◽

Hurricane Bonnie

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Analysis of water vapor LIDAR measurements during the MAP campaign: evidence of sub-structures of stratospheric intrusions

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-1301-2005 ◽

2005 ◽

Vol 5 (5) ◽

pp. 1301-1310 ◽

Cited By ~ 8

Author(s):

P. D'Aulerio ◽

F. Fierli ◽

F. Congeduti ◽

G. Redaelli

Keyword(s):

Water Vapor ◽

Northern Italy ◽

Alpine Region ◽

Vapor Concentration ◽

Small Scale ◽

Raman Lidar ◽

Lidar Measurements ◽

Stratospheric Intrusions ◽

Vapor Distribution ◽

High Potential Vorticity

Abstract. This paper presents two case studies of transport of dry air in the free troposphere measured by a ground based Raman LIDAR in the Northern-Italy, during the Mesoscale Alpine Programme (MAP). Two observations characterized by the presence of anomalously dry layers, below 6 km height, were analyzed using Lagrangian techniques. These events are related to upper-tropospheric, high Potential Vorticity (PV) streamers crossing the Alpine region. These are interpreted as small-scale features of stratospheric intrusions associated with the PV ridge during its phase of dissipation. One of the measurements also shows the presence of two distinct dehydrated structures associated with the same event. The water vapor concentration also suggests dilution processes of dry stratospheric air in the troposphere. Lagrangian simulations allowed to successfully reproduce the observed water vapor distribution and the air parcel histories confirmed the stratospheric origin of the dry layers.

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The mobile Water vapor Aerosol Raman LIdar and its implication in the framework of the HyMeX and ChArMEx programs: application to a dust transport process

Atmospheric Measurement Techniques ◽

10.5194/amt-7-1629-2014 ◽

2014 ◽

Vol 7 (6) ◽

pp. 1629-1647 ◽

Cited By ~ 34

Author(s):

P. Chazette ◽

F. Marnas ◽

J. Totems

Keyword(s):

Water Vapor ◽

Raman Lidar ◽

Scientific Application ◽

Dust Transport ◽

New Device ◽

Dust Aerosols ◽

Lidar Measurements ◽

Lidar Ratio ◽

Observation Tools ◽

Water Vapor Mixing Ratio

Abstract. The increasing importance of the coupling of water and aerosol cycles in environmental applications requires observation tools that allow simultaneous measurements of these two fundamental processes for climatological and meteorological studies. For this purpose, a new mobile Raman lidar, WALI (Water vapor and Aerosol LIdar), has been developed and implemented within the framework of the international HyMeX and ChArMEx programs. This paper presents the key properties of this new device and its first applications to scientific studies. The lidar uses an eye-safe emission in the ultraviolet range at 354.7 nm and a set of compact refractive receiving telescopes. Cross-comparisons between rawinsoundings performed from balloon or aircraft and lidar measurements have shown a good agreement in the derived water vapor mixing ratio (WVMR). The discrepancies are generally less than 0.5 g kg−1 and therefore within the error bars of the respective instruments. A detailed study of the uncertainty of the WVMR retrieval was conducted and shows values between 7 and 11%, which is largely constrained by the quality of the lidar calibration. It also proves that the lidar is able to measure the WVMR during daytime over a range of about 1 km. In addition the WALI system provides measurements of aerosol optical properties such as the lidar ratio (LR) or the particulate depolarization ratio (PDR). An important example of scientific application addressing the main objectives of the HyMeX and ChArMEx programs is then presented, following an event of desert dust aerosols over the Balearic Islands in October 2012. This dust intrusion may have had a significant impact on the intense precipitations that occurred over southwestern France and the Spanish Mediterranean coasts. During this event, the LR and PDR values obtained are in the ranges of ~45–63 ± 6 and 0.10–0.19 ± 0.01 sr, respectively, which is representative of dust aerosols. The dust layers are also shown to be associated with significant WVMR, i.e., between 4 and 6.7 g kg−1.

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Daytime Raman-lidar measurements of water vapor

Optics Letters ◽

10.1364/ol.5.000233 ◽

1980 ◽

Vol 5 (6) ◽

pp. 233 ◽

Cited By ~ 46

Author(s):

D. Renaut ◽

J. C. Pourny ◽

R. Capitini

Keyword(s):

Water Vapor ◽

Raman Lidar ◽

Lidar Measurements

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The mobile Water vapor Aerosol Raman LIdar and its implication in the frame of the HyMeX and ChArMEx programs: application to a dust transport process

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-6-10653-2013 ◽

2013 ◽

Vol 6 (6) ◽

pp. 10653-10698 ◽

Cited By ~ 2

Author(s):

P. Chazette ◽

F. Marnas ◽

J. Totems

Keyword(s):

Water Vapor ◽

Ultra Violet ◽

Raman Lidar ◽

Scientific Application ◽

Dust Transport ◽

New Device ◽

Dust Aerosols ◽

Lidar Measurements ◽

Observation Tools ◽

Water Vapor Mixing Ratio

Abstract. The increasing importance of the coupling of water and aerosol cycles in environmental applications requires observation tools which allow simultaneous measurements of these two fundamental processes for climatological and meteorological studies. In this purpose, a new mobile Raman lidar, WALI (Water vapor and Aerosol LIDAR), has been developed and implemented within the framework of the international HyMeX/IODA-MED and ChArMEx programs. This paper presents the key properties of this new device and its first applications to scientific studies. The lidar uses an eye-safe emission in the ultra-violet range at 354.7 nm and a set of compact refractive receptors. Cross-comparisons between rawindsoundings performed from balloon or aircraft and lidar measurements have shown a good agreement in the derived water vapor mixing ratio (WVMR). The discrepancies are generally less than 0.5 g kg−1 and therefore within the error bars of the instruments. A detailed study of the uncertainties was conducted and shows a 7 to 11% accuracy of the WVMR retrieval, which is largely constrained by the quality of the calibration. It also proves that the lidar is able to measure the WVMR during the day over a range of about 1 km. The WALI system otherwise provides measurements of aerosol optical properties such as the lidar ratio (LR) or the particulate depolarization ratio (PDR). An important example of scientific application addressing the main objectives of the HyMeX and ChArMEx programs is then presented, following an event of desert dust aerosols over the Balearic Islands. This dust intrusion may have had a significant impact on the intense precipitations that occurred over southwestern France and the Spanish Mediterranean coasts. During this event, the LR and PDR values obtained are in the ranges of ~ 45–63 ± 6 sr and 0.1–0.19 ± 0.01, respectively, which is representative of dust aerosols. The dust layers are also shown to be associated with significant WVMR, i.e. between 4 and 6.7 g kg−1.

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