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Dambaru Ballab Kattel - One of the best experts on this subject based on the ideXlab platform.
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near surface air temperature Lapse Rate in a humid mountainous terrain on the southern slopes of the eastern himalayas
Theoretical and Applied Climatology, 2018Co-Authors: Dambaru Ballab Kattel, Prajjwal K PandayAbstract:Based on climatic data from 18 stations on the southern slopes of the eastern Himalayas in Bhutan for the period from 1996 to 2009, this paper investigates monthly characteristics of the near-surface air temperature Lapse Rate (TLR). The station elevations used in this study range from 300 to 2760 m a. s. l. TLRs were evaluated using a linear regression model. The monthly values of maximum TLRs were always smaller than those of the minimum TLRs, which is in contrast to results from the surrounding mountainous regions. In this study, annual patterns of TLRs were somewhat consistent, particularly in the summer; during the other seasons, patterns contrasted to results from the southeastern Tibetan Plateau (China) and were almost comparable to results from Nepal. The shallowest observed values for TLRs in summer are due to intense latent heating at the higher elevation, associated with water vapor condensation from moist convection and evapotranspiration, and decreasing sensible heating at lower elevation, due to heavier rainfall, cloud, and forest cover. When compared to summer, the steeper TLRs in the non-monsoon season are due to sensible heating at the lower elevations, corresponding to dry and clear weather seasons, as well as increasing cooling at higher elevations, particularly in winter due to snow and cloud cover. Owing to lower albedo and higher aerodynamic roughness of forested areas, the TLRs were considerably reduced in daytime because of the dissipation of sensible heat to the atmospheric boundary layer. The distinct variation in diurnal TLR range is due to the diurnal variation in net radiation associated with reduced turbulent heating in the day and increased turbulent heating in the night, in addition to the effect of moisture and cloud cover. The shallower values of TLRs in this study when compared with the surrounding mountainous regions are due to high humidity, as well as the differing elevations and local climates.
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temperature Lapse Rate in complex mountain terrain on the southern slope of the central himalayas
Theoretical and Applied Climatology, 2013Co-Authors: Dambaru Ballab Kattel, Kun Yang, Lide Tian, G Yang, Daniel R JoswiakAbstract:This study presents the first results of monthly, seasonal and annual characteristics of temperature Lapse Rate on the southern slope of the central Himalayas, based on 20 years record of surface air temperature at 56 stations in Nepal. These stations are located at a range of elevations between 72 and 3,920 m above sea level. It is proven that the Lapse Rate can be calculated with a linear regression model. The annual cycle of temperature Lapse Rate exhibits a bi-modal pattern: two maxima in the pre- and post-monsoon seasons respectively sepaRated by two minima in winter and summer, respectively. This pattern is different from the findings from the other mountain regions and suggests different controlling factors in the individual seasons. The highest temperature Lapse Rate occurs in the pre-monsoon and is associated with strong dry convection (i.e., corresponding to the clear weather season and considerable sensible heat flux). The post-monsoon has the second highest Lapse Rate, and its cause is similar to the pre-monsoon season but with a relatively small thermal forcing effect after the rainy summer. The lowest Lapse Rate occurs in winter and is associated with strong radiative cooling and cold air flows over low-elevation areas. The summer Lapse Rate minimum is due to latent heating over the higher elevations and reduced solar heating over the lower elevations.
Sean C C Bailey - One of the best experts on this subject based on the ideXlab platform.
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university of kentucky measurements of wind temperature pressure and humidity in support of Lapse Rate using multisite fixed wing and rotorcraft unmanned aerial systems
Earth System Science Data, 2020Co-Authors: Sean C C Bailey, Michael P Sama, Caleb Canter, Felipe L Pampolini, Zachary S Lippay, Travis J Schuyler, Jonathan D Hamilton, Sean B MacpheeAbstract:Abstract. In July 2018, unmanned aerial systems (UASs) were deployed to measure the properties of the lower atmosphere within the San Luis Valley, an elevated valley in Colorado, USA, as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate). Measurement objectives included detailing boundary layer transition, canyon cold-air drainage and convection initiation within the valley. Details of the contribution to Lapse-Rate made by the University of Kentucky are provided here, which include measurements by seven different fixed-wing and rotorcraft UASs totaling over 178 flights with validated data. The data from these coordinated UAS flights consist of thermodynamic and kinematic variables (air temperature, humidity, pressure, wind speed and direction) and include vertical profiles up to 900 m above the ground level and horizontal transects up to 1500 m in length. These measurements have been quality controlled and are openly available in the Zenodo Lapse-Rate community data repository ( https://zenodo.org/communities/Lapse-Rate/ , last access: 23 July 2020), with the University of Kentucky data available at https://doi.org/10.5281/zenodo.3701845 ( Bailey et al. , 2020 ).
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university of kentucky measurements of wind temperature pressure and humidity in support of Lapse Rate using multi sitefixed wing and rotorcraft uas
Earth System Science Data Discussions, 2020Co-Authors: Sean C C Bailey, Michael P Sama, Caleb Canter, Felipe L Pampolini, Zachary S Lippay, Travis J Schuyler, Jonathan D Hamilton, Sean B Macphee, Isaac S Rowe, Christopher D SandersAbstract:Abstract. In July 2018, unmanned aerial systems (UAS) were deployed to measure the properties of lower atmosphere within the San Luis Valley, an elevated valley in Colorado, USA as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate). Measurement objectives included detailing boundary-layer transition, canyon cold-air drainage, and convection initiation within the valley. Details of the contribution to Lapse-Rate made by University of Kentucky are provided here, which include measurements by seven different fixed-wing and rotorcraft UAS totaling over 178 flights with validated data. The data from these coordinated UAS flights consist of thermodynamic and kinematic variables (air temperature, humidity, pressure, wind speed and direction) and include vertical profiles up to 900 m above the ground level and horizontal transects up to 1500 m in length. These measurements have been quality controlled and are openly available in the Zenodo Lapse-Rate community data repository ( https://zenodo.org/communities/Lapse-Rate/ ), with the University of Kentucky data available at https://doi.org/10.5281/zenodo.3701845 (Bailey et al., 2020).
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intercomparison of small unmanned aircraft system suas measurements for atmospheric science during the Lapse Rate campaign
Sensors, 2019Co-Authors: Lindsay Barbieri, Jamey Jacob, Phillip B Chilson, Sean C C Bailey, Stephan T Kral, Amy E Frazier, Joachim Reuder, D Brus, Christopher Crick, Carrick DetweilerAbstract:Small unmanned aircraft systems (sUAS) are rapidly transforming atmospheric research. With the advancement of the development and application of these systems, improving knowledge of best practices for accuRate measurement is critical for achieving scientific goals. We present results from an intercomparison of atmospheric measurement data from the Lower Atmospheric Process Studies at Elevation—a Remotely piloted Aircraft Team Experiment (Lapse-Rate) field campaign. We evaluate a total of 38 individual sUAS with 23 unique sensor and platform configurations using a meteorological tower for reference measurements. We assess precision, bias, and time response of sUAS measurements of temperature, humidity, pressure, wind speed, and wind direction. Most sUAS measurements show broad agreement with the reference, particularly temperature and wind speed, with mean value differences of 1.6 ± 2.6 ∘ C and 0.22 ± 0.59 m/s for all sUAS, respectively. sUAS platform and sensor configurations were found to contribute significantly to measurement accuracy. Sensor configurations, which included proper aspiration and radiation shielding of sensors, were found to provide the most accuRate thermodynamic measurements (temperature and relative humidity), whereas sonic anemometers on multirotor platforms provided the most accuRate wind measurements (horizontal speed and direction). We contribute both a characterization and assessment of sUAS for measuring atmospheric parameters, and identify important challenges and opportunities for improving scientific measurements with sUAS.
Kun Yang - One of the best experts on this subject based on the ideXlab platform.
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improving snow process modeling with satellite based estimation of near surface air temperature Lapse Rate
Journal of Geophysical Research, 2016Co-Authors: Kun Yang, Lei Wang, Litao Sun, Maheswor Shrestha, Wenbin Liu, Jing Zhou, Deliang ChenAbstract:In distributed hydrological modeling, surface air temperature (Tair) is of great importance in simulating cold region processes, while the near-surface-air-temperature Lapse Rate (NLR) is crucial to prepare Tair (when interpolating Tair from site observations to model grids). In this study, a distributed biosphere hydrological model with improved snow physics (WEB-DHM-S) was rigorously evaluated in a typical cold, large river basin (e.g., the upper Yellow River basin), given a mean monthly NLRs. Based on the validated model, we have examined the influence of the NLR on the simulated snow processes and streamflows. We found that the NLR has a large effect on the simulated streamflows, with a maximum difference of greater than 24% among the various scenarios for NLRs considered. To supplement the insufficient number of monitoring sites for near-surface-air-temperature at developing/undeveloped mountain regions, the nighttime ModeRate Resolution Imaging Spectroradiometer land surface temperature is used as an alternative to derive the approximate NLR at a finer spatial scale (e.g., at different elevation bands, different land covers, different aspects, and different snow conditions). Using satellite-based estimation of NLR, the modeling of snow processes has been greatly refined. Results show that both the determination of rainfall/snowfall and the snowpack process were significantly improved, contributing to a reduced summer evapotranspiration and thus an improved streamflow simulation.
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temperature Lapse Rate in complex mountain terrain on the southern slope of the central himalayas
Theoretical and Applied Climatology, 2013Co-Authors: Dambaru Ballab Kattel, Kun Yang, Lide Tian, G Yang, Daniel R JoswiakAbstract:This study presents the first results of monthly, seasonal and annual characteristics of temperature Lapse Rate on the southern slope of the central Himalayas, based on 20 years record of surface air temperature at 56 stations in Nepal. These stations are located at a range of elevations between 72 and 3,920 m above sea level. It is proven that the Lapse Rate can be calculated with a linear regression model. The annual cycle of temperature Lapse Rate exhibits a bi-modal pattern: two maxima in the pre- and post-monsoon seasons respectively sepaRated by two minima in winter and summer, respectively. This pattern is different from the findings from the other mountain regions and suggests different controlling factors in the individual seasons. The highest temperature Lapse Rate occurs in the pre-monsoon and is associated with strong dry convection (i.e., corresponding to the clear weather season and considerable sensible heat flux). The post-monsoon has the second highest Lapse Rate, and its cause is similar to the pre-monsoon season but with a relatively small thermal forcing effect after the rainy summer. The lowest Lapse Rate occurs in winter and is associated with strong radiative cooling and cold air flows over low-elevation areas. The summer Lapse Rate minimum is due to latent heating over the higher elevations and reduced solar heating over the lower elevations.
Gijs De Boer - One of the best experts on this subject based on the ideXlab platform.
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data geneRated during the 2018 Lapse Rate campaign an introduction and overview
Earth System Science Data, 2020Co-Authors: Gijs De Boer, Adam L Houston, Brian Argrow, Jamey Jacob, Phillip B Chilson, Suzanne Weaver Smith, Dale Lawrence, Jack Elston, David BrusAbstract:Abstract. Unmanned aircraft systems (UASs) offer innovative capabilities for providing new perspectives on the atmosphere, and therefore atmospheric scientists are rapidly expanding their use, particularly for studying the planetary boundary layer. In support of this expansion, from 14 to 20 July 2018 the International Society for Atmospheric Research using Remotely piloted Aircraft (ISARRA) hosted a community flight week, dubbed the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate; de Boer et al., 2020a). This field campaign spanned a 1-week deployment to Colorado's San Luis Valley, involving over 100 students, scientists, engineers, pilots, and outreach coordinators. These groups conducted intensive field operations using unmanned aircraft and ground-based assets to develop comprehensive datasets spanning a variety of scientific objectives, including a total of nearly 1300 research flights totaling over 250 flight hours. This article introduces this campaign and lays the groundwork for a special issue on the Lapse-Rate project. The remainder of the special issue provides detailed overviews of the datasets collected and the platforms used to collect them. All of the datasets covered by this special issue have been uploaded to a Lapse-Rate community set up at the Zenodo data archive ( https://zenodo.org/communities/Lapse-Rate/ , last access: 3 December 2020).
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university of colorado and black swift technologies rpas based measurements of the lower atmosphere during Lapse Rate
Earth System Science Data Discussions, 2020Co-Authors: Gijs De Boer, Steven Borenstein, Cory Dixon, Dale Lawrence, Jack Elston, Daniel Hesselius, Maciej Stachura, Roger J Laurence, Sara SwensonAbstract:Abstract. Between 14 and 20 July 2018, small remotely-piloted aircraft systems (RPAS) were deployed to the San Luis Valley of Colorado (USA) together with a variety of surface-based remote and in-situ sensors, and radiosonde systems as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate). The observations from Lapse-Rate were aimed at improving our understanding of boundary layer structure, cloud and aerosol properties and surface-atmosphere exchange, and provide detailed information to support model evaluation and improvement work. The current manuscript describes the observations obtained using four different types of RPAS deployed by the University of Colorado Boulder and Black Swift Technologies. These included the DataHawk2, the Talon and the TTwistor (U. of Colorado) and the S1 (Black Swift Technologies). Together, these aircraft collected over 30 hours of data throughout the northern half of the San Luis Valley, sampling altitudes between the surface and 914 m AGL. Data from these platforms are publicly available through the Zenodo archive, and are co-located with other Lapse-Rate data as part of the Zenodo Lapse-Rate community ( https://zenodo.org/communities/Lapse-Rate/ ). The primary DOIs for these datasets are https://doi.org/10.5281/zenodo.3891620 (DataHawk2, de Boer et al., 2020a), https://doi.org/10.5281/zenodo.4096451 (Talon, de Boer et al., 2020b), https://doi.org/10.5281/zenodo.4110626 (TTWISTOR, de Boer et al., 2020c), and https://doi.org/10.5281/zenodo.3861831 (S1, Elston and Stachura, 2020).
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atmospheric aerosol gases and meteorological parametersmeasured during the Lapse Rate campaign
Earth System Science Data Discussions, 2020Co-Authors: David Brus, Jani Gustafsson, Osku Kempinen, Gijs De Boer, Anne HirsikkoAbstract:Abstract. Small Unmanned Aerial Systems (sUAS) are becoming very popular as affordable and reliable observation platforms. The Lower Atmospheric Process Studies at Elevation - a Remotely-piloted Aircraft Team Experiment (Lapse-Rate), conducted in the San Luis Valley of Colorado (USA) between July 14th – 20th, 2018, gathered together numerous sUAS, remote sensing equipment and ground based instrumentation. Flight teams from the Finnish Meteorological Institute and the Kansas State University co-opeRated during Lapse-Rate to measure and investigate the properties of aerosol particles and gases at the surface and in the lower atmosphere. During Lapse-Rate the deployed instrumentation opeRated reliably, resulting in a scientifically sound observational dataset. Our observations included aerosol particle number concentrations and size distributions, concentrations of CO2 and water vapor, and meteorological parameters. All data sets have been uploaded to the Zenodo Lapse-Rate community archive ( https://zenodo.org/communities/Lapse-Rate/ ). The dataset DOIs for FMI airborne measurements and surface measurements are available here: https://doi.org/10.5281/zenodo.3993996 , Brus et al. (2020a), and for KSU airborne measurements and surface measurements are available here: https://doi.org/10.5281/zenodo.3736772 , Brus et al. (2020b).
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measurements from mobile surface vehicles during Lapse Rate
Earth System Science Data Discussions, 2020Co-Authors: Gijs De Boer, Sean Waugh, Alexander Erwin, Steven Borenstein, Cory Dixon, Wafaa Shanti, Adam L Houston, Brian ArgrowAbstract:Abstract. Between 14 and 20 July 2018, small unmanned aircraft systems (sUAS) were deployed to the San Luis Valley of Colorado (USA) alongside surface-based remote, in-situ sensors, and radiosonde systems as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate). The measurements collected as part of Lapse-Rate targeted quantities related to enhancing our understanding of boundary layer structure, cloud and aerosol properties and surface-atmosphere exchange, and provide detailed information to support model evaluation and improvement work. Additionally, intensive intercomparison between the different unmanned aircraft platforms was completed. The current manuscript describes the observations obtained using three different types of surface-based mobile observing vehicles. These included the University of Colorado Mobile UAS Research Collaboratory (MURC), the National Oceanic and Atmospheric Administration National Severe Storms Laboratory Mobile Mesonet, and two University of Nebraska Combined Mesonet and Tracker (CoMeT) vehicles. Over the one-week campaign, a total of 143 hours of data were collected using this combination of vehicles. The data from these coordinated activities provide detailed perspectives on the spatial variability of atmospheric state parameters (air temperature, humidity, pressure, and wind) throughout the northern half of the San Luis Valley. These data sets have been checked for quality and published to the Zenodo data archive under a specific community set up for Lapse-Rate ( https://zenodo.org/communities/Lapse-Rate/ ) and are accessible at no cost by all registered users. The primary dataset DOIs are https://doi.org/10.5281/zenodo.3814765 (CU MURC measurements; de Boer et al., 2020d), https://doi.org/10.5281/zenodo.3738175 (NSSL MM measurements; Waugh, 2020) and https://doi.org/10.5281/zenodo.3838724 (UNL CoMeT measurements; Houston and Erwin., 2020).
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measurement report properties of aerosol and gases in the vertical profile during the Lapse Rate campaign
Atmospheric Chemistry and Physics, 2020Co-Authors: David Brus, Jani Gustafsson, Gijs De Boer, Ville Vakkari, Osku Kemppinen, Anne HirsikkoAbstract:Abstract. Unmanned Aerial Systems (UASs) are increasingly being used as observation platforms for atmospheric applications. The Lower Atmospheric Process Studies at Elevation – a Remotely-piloted Aircraft Team Experiment (Lapse-Rate) in Alamosa, CO, USA during July 14th–20th, 2018 investigated and validated different UASs, measurement sensors and setup configurations. Flight teams from the Finnish Meteorological Institute (FMI) and the Kansas State University (KSU) participated in Lapse-Rate to measure and investigate properties of aerosol particles and gases in the lower atmosphere. During the experiment, the performance of different UAS configurations were investigated and confirmed to opeRate reliably resulting in a scientifically sound observational dataset. As an example, concentration of aerosols – including two new particle formation events, CO2 and water vapor, and meteorological parameters in the atmospheric vertical profile were measured during the short experiment. Such observations characterizing atmospheric phenomena of this specific environment would have not been possible in any other way, and thus, demonstRate power of UASs as new, promising tools in atmospheric and environmental research.
Lei Wang - One of the best experts on this subject based on the ideXlab platform.
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improving snow process modeling with satellite based estimation of near surface air temperature Lapse Rate
Journal of Geophysical Research, 2016Co-Authors: Kun Yang, Lei Wang, Litao Sun, Maheswor Shrestha, Wenbin Liu, Jing Zhou, Deliang ChenAbstract:In distributed hydrological modeling, surface air temperature (Tair) is of great importance in simulating cold region processes, while the near-surface-air-temperature Lapse Rate (NLR) is crucial to prepare Tair (when interpolating Tair from site observations to model grids). In this study, a distributed biosphere hydrological model with improved snow physics (WEB-DHM-S) was rigorously evaluated in a typical cold, large river basin (e.g., the upper Yellow River basin), given a mean monthly NLRs. Based on the validated model, we have examined the influence of the NLR on the simulated snow processes and streamflows. We found that the NLR has a large effect on the simulated streamflows, with a maximum difference of greater than 24% among the various scenarios for NLRs considered. To supplement the insufficient number of monitoring sites for near-surface-air-temperature at developing/undeveloped mountain regions, the nighttime ModeRate Resolution Imaging Spectroradiometer land surface temperature is used as an alternative to derive the approximate NLR at a finer spatial scale (e.g., at different elevation bands, different land covers, different aspects, and different snow conditions). Using satellite-based estimation of NLR, the modeling of snow processes has been greatly refined. Results show that both the determination of rainfall/snowfall and the snowpack process were significantly improved, contributing to a reduced summer evapotranspiration and thus an improved streamflow simulation.
