scholarly journals Selecting Characteristic Raman Wavelengths to Distinguish Liquid Water, Water Vapor, and Ice Water

2010 ◽  
Vol 14 (3) ◽  
pp. 209-214 ◽  
Author(s):  
Sun-Ho Park ◽  
Yong-Gi Kim ◽  
Duk-Hyeon Kim ◽  
Hai-Du Cheong ◽  
Won-Seok Choi ◽  
...  
Keyword(s):  
Water Vapor ◽  
Liquid Water ◽  
Ice Water

scholarly journals Raman Lidar for Synchronous Water Vapor, Liquid Water and Ice Water Profilings

2020 ◽  
Vol 237 ◽  
pp. 06013
Author(s):  
Wang Yufeng ◽  
Zhang Jing ◽  
Wang Qing ◽  
Gao Fei ◽  
Di Huige ◽  
...  
Keyword(s):  
Water Vapor ◽  
Liquid Water ◽  
Weather Condition ◽  
Atmospheric Parameter ◽  
Raman Lidar ◽  
Cloudy Weather ◽  
Three Phase ◽  
Phase Water ◽  
Ice Water ◽  
Vapor Liquid

Water is the only atmospheric parameter with three-phase state. An ultraviolet Raman lidar was developed for synchronous measurements for water vapor, liquid water and ice water in Xi’an University of Technology, Xi’an, China (34.233°N, 108.911°E). An accurate retrieval method on the basis of interference degree is proposed for synchronous three-phase water mixing ratio profiles. Preliminary measurements are carried out in the Laser Radar Center of Remote Sensing of Atmosphere (LRCRSA). Several representative examples are obtained and validated the performance of Raman system. Combined with atmospheric temperature profiles, the synchronous water vapor, liquid water and ice water profiling are retrieved and revealed the variation characteristics in three-phase water. The effective detection can reach up to a height of 5 km under cloudy weather, and synchronized growth in water vapor and liquid water content was obtained in cloud layers. Continuous observations are also made under haze weather condition, and the temporal and spatial evolution trend of three-phase water in clouds at 2 km altitude are successfully realized.

scholarly journals Measuring ice- and liquid-water properties in mixed-phase cloud layers at the Leipzig Cloudnet station

2016 ◽  
Vol 16 (16) ◽  
pp. 10609-10620 ◽  
Author(s):  
Johannes Bühl ◽  
Patric Seifert ◽  
Alexander Myagkov ◽  
Albert Ansmann
Keyword(s):  
Water Content ◽  
Liquid Water ◽  
Mass Flux ◽  
Mixed Phase ◽  
Cloud Base ◽  
Doppler Velocity ◽  
Special Focus ◽  
Data Set ◽  
Ice Water Content ◽  
Ice Water

Abstract. An analysis of the Cloudnet data set collected at Leipzig, Germany, with special focus on mixed-phase layered clouds is presented. We derive liquid- and ice-water content together with vertical motions of ice particles falling through cloud base. The ice mass flux is calculated by combining measurements of ice-water content and particle Doppler velocity. The efficiency of heterogeneous ice formation and its impact on cloud lifetime is estimated for different cloud-top temperatures by relating the ice mass flux and the liquid-water content at cloud top. Cloud radar measurements of polarization and Doppler velocity indicate that ice crystals formed in mixed-phase cloud layers with a geometrical thickness of less than 350 m are mostly pristine when they fall out of the cloud.

Variational Assimilation of Cloud Liquid/Ice Water Path and Its Impact on NWP

2015 ◽  
Vol 54 (8) ◽  
pp. 1809-1825 ◽  
Author(s):  
Yaodeng Chen ◽  
Hongli Wang ◽  
Jinzhong Min ◽  
Xiang-Yu Huang ◽  
Patrick Minnis ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Liquid Water ◽  
Weather Prediction ◽  
Wrf Model ◽  
Liquid Water Path ◽  
Cloud Liquid Water ◽  
Water Path ◽  
Ice Water Path ◽  
Ice Water ◽  
The Impact

AbstractAnalysis of the cloud components in numerical weather prediction models using advanced data assimilation techniques has been a prime topic in recent years. In this research, the variational data assimilation (DA) system for the Weather Research and Forecasting (WRF) Model (WRFDA) is further developed to assimilate satellite cloud products that will produce the cloud liquid water and ice water analysis. Observation operators for the cloud liquid water path and cloud ice water path are developed and incorporated into the WRFDA system. The updated system is tested by assimilating cloud liquid water path and cloud ice water path observations from Global Geostationary Gridded Cloud Products at NASA. To assess the impact of cloud liquid/ice water path data assimilation on short-term regional numerical weather prediction (NWP), 3-hourly cycling data assimilation and forecast experiments with and without the use of the cloud liquid/ice water paths are conducted. It is shown that assimilating cloud liquid/ice water paths increases the accuracy of temperature, humidity, and wind analyses at model levels between 300 and 150 hPa after 5 cycles (15 h). It is also shown that assimilating cloud liquid/ice water paths significantly reduces forecast errors in temperature and wind at model levels between 300 and 150 hPa. The precipitation forecast skills are improved as well. One reason that leads to the improved analysis and forecast is that the 3-hourly rapid update cycle carries over the impact of cloud information from the previous cycles spun up by the WRF Model.

scholarly journals The Impacts of Atmospheric and Surface Parameters on Long-Term Variations in the Planetary Albedo

2018 ◽  
Vol 31 (21) ◽  
pp. 8705-8718 ◽  
Author(s):  
Bida Jian ◽  
Jiming Li ◽  
Guoyin Wang ◽  
Yongli He ◽  
Ying Han ◽  
...  
Keyword(s):  
Liquid Water ◽  
Surface Albedo ◽  
Cloud Fraction ◽  
Liquid Water Path ◽  
Water Path ◽  
Ice Water Path ◽  
Planetary Albedo ◽  
Ice Water ◽  
Long Term Variations

Planetary albedo (PA; shortwave broadband albedo) and its long-term variations, which are controlled in a complex way by various atmospheric and surface properties, play a key role in controlling the global and regional energy budget. This study investigates the contributions of different atmospheric and surface properties to the long-term variations of PA based on 13 years (2003–15) of albedo, cloud, and ice coverage datasets from the Clouds and the Earth’s Radiant Energy System (CERES) Single Scanner Footprint edition 4A product, vegetation product from Moderate Resolution Imaging Spectroradiometer (MODIS), and surface albedo product from the Cloud, Albedo, and Radiation dataset, version 2 (CLARA-A2). According to the temporal correlation analysis, statistical results indicate that variations in PA are closely related to the variations of cloud properties (e.g., cloud fraction, ice water path, and liquid water path) and surface parameters (e.g., ice/snow percent coverage and normalized difference vegetation index), but their temporal relationships vary among the different regions. Generally, the stepwise multiple linear regression models can capture the observed PA anomalies for most regions. Based on the contribution calculation, cloud fraction dominates the variability of PA in the mid- and low latitudes while ice/snow percent coverage (or surface albedo) dominates the variability in the mid- and high latitudes. Changes in cloud liquid water path and ice water path are the secondary dominant factor over most regions, whereas change in vegetation cover is the least important factor over land. These results verify the effects of atmospheric and surface factors on planetary albedo changes and thus may be of benefit for improving the parameterization of the PA and determining the climate feedbacks.

scholarly journals Drying parameters of rendering mortars

2018 ◽  
Vol 18 (2) ◽  
pp. 7-19 ◽  
Author(s):  
Maria Cláudia de Freitas Salomão ◽  
Elton Bauer ◽  
Claudio de Souza Kazmierczak
Keyword(s):  
Water Vapor ◽  
Water Transport ◽  
Liquid Water ◽  
Water Vapor Permeability ◽  
Water Vapor Transport ◽  
Experimental Program ◽  
Vapor Permeability ◽  
Capillary Absorption ◽  
Drying Behavior ◽  
Drying Curves

Abstract The objective of this article was to study the drying behavior of rendering mortars. Cement-lime mortars with different mix proportions were evaluatedto analyze the influence of mix materials on water transport. The experimental program was produced to observe the transport of liquid water and vapor water in mortars during the drying process. The liquid water transport was studied through capillary absorption and the water vapor transport by the water vapor permeability test. The drying curves used to investigate drying kinetics were obtained according to the methodology recommended by European standard EN 16322. In summary, it is possible to affirm that the aggregate, the binder and water contents determine the behavior of the mortars regarding water transport. The drying index is considered a good indicator of the easiness of both liquid and vapor water transport.

Coupled Liquid Water, Water Vapor, and Heat Transport Simulations in an Unsaturated Zone of a Sandy Loam Field

Soil Science ◽  
2011 ◽  
Vol 176 (8) ◽  
pp. 387-398 ◽  
Author(s):  
Sanjit K. Deb ◽  
Manoj K. Shukla ◽  
Parmodh Sharma ◽  
John G. Mexal
Keyword(s):  
Water Vapor ◽  
Heat Transport ◽  
Liquid Water ◽  
Unsaturated Zone ◽  
Sandy Loam

scholarly journals Spectrally-Resolved Raman Lidar to Measure Atmospheric Three-Phase Water Simultaneously

2020 ◽  
Vol 237 ◽  
pp. 06017
Author(s):  
Fuchao Liu ◽  
Fan Yi
Keyword(s):  
Water Vapor ◽  
Raman Spectra ◽  
Weather Conditions ◽  
Cloud Microphysics ◽  
Raman Lidar ◽  
Atmospheric Water ◽  
Three Phase ◽  
Phase Water ◽  
Spectrally Resolved ◽  
Ice Water

We report on a spectrally-resolved Raman lidar that can simultaneously profile backscattered Raman spectrum signals from water vapor, water droplets and ice crystals as well as aerosol fluorescence in the atmosphere. The lidar emits a 354.8-nm ultraviolet laser radiation and samples echo signals in the 393.0-424.0 nm wavelength range with a 1.0-nm spectral resolution. A spectra decomposition method is developed to retrieve fluorescence spectra, water vapor Raman spectra and condensed (liquid and/or ice) water Raman spectra successively. Based on 8 different clear-sky nighttime measurement results, the entire atmospheric water vapor Raman spectra are for the first time obtained by lidar. The measured normalized water vapor Raman spectra are nearly invariant and can serve as background reference for atmospheric water phase state identification under various weather conditions. For an ice virga event, it’s found the extracted condensed water Raman spectra are highly similar in shape to theoretical ice water Raman spectra reported by Slusher and Derr (1975). In conclusion, the lidar provides an effective way to measure three-phase water simultaneously in the atmosphere and to study of cloud microphysics as well as interaction between aerosols and clouds.

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