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This dataset comes from a rotary-wing, weather-sensing uncrewed aerial system called the CopterSonde. Temperature, pressure, humidity, wind speed, and direction are gathered during vertical profiles. The vertical resolution is 5 m up to 609 m above ground level and the temporal resolution is on average 30 minutes.
The dataset presents atmospheric mass loadings of black carbon (BC) and brown carbon (BrC), during the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign that took place from 2021 – 2023 in Gothic, CO. A Magee Scientific aethalometer (model AE33) was deployed at the Rocky Mountain Biological Laboratory, 200 m north of AMF2 to monitor mass loadings of optically absorbing aerosols. The instrument inlet was equipped with a BGI SCC 1.829 ambient cyclone with a particle cutoff of 2.5 μm and placed 5 m above ground level. The dataset reports hour-resolved BC mass loadings at 370, 470, 520, 590, 660, 880, and 950 (BC370, BC470, BC 520, BC590, BC660, BC880, BC950 in ng/m3) reported by the instrument built-in algorithm, which calculates mass loadings from the rate of change of the attenuation of light transmitted through the aerosol-laden filter. BC880 is the operationally defined reference of the BC concentration. Hour-resolved absorbance at each wavelength were calculated from their respective mass absorption cross-section in inverse megameters (Mm-1). The absorption Angstrom exponent (AAE) for BrC and BC were calculated for each hour. BrC AAE (AAE_BrC) was calculated from the slope of Log(wavelength) versus Log(absorbance) based on the measurements at 370, 470, and 520 nm. BC AAE (AAE_BrC) was calculated from the slope of Log(wavelength) versus Log(absorbance) based on the measurements at 590, 660, 880, and 950 nm. The aethalometer record spans time periods of 4/5/2022 – 10/3/2022 and 12/8/2022 – 10/9/2023. The ambient CO2 concentration recorded by a Vaisala CARBOCAP carbon dioxide probe GMP343 is also reported in ppm.
The dataset presents the time tags of individual particle samples collected on microscopy substrates during the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign in Gothic, CO. A Time Resolved Aerosol Collector was deployed at the Rocky Mountain Biological Laboratory, 200 m north of AMF2 to collect ambient particles. The instrument inlet was placed 5 m above ground level. Particles are deposited on 400 mesh copper carbon-B film TEM grids (Ted Pella 01814-F). Samples are sealed and currently stored at Purdue University. A subset of the samples can be shared. Please contact dataset authors for more information. The dataset reports the sample start times in UTC and MST along with the sample ID, used to guide its location and retrieval from the storage plate. TRAC sampling started on June 17, 2023, and ended on July 31, 2023.
This data set contains air mass back trajectories generated during the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign using the Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT, Stein et al. 2015, Rolph et al. 2017). For each hour from January 1, 2021 to June 30, 2023, a 96-hour back trajectory was initiated at the SAIL sampling site, starting 100 m above ground level. The calculations used the GDAS meteorological data set with model vertical velocity. The files within this dataset show location and meteorological parameters of the back trajectory analysis. There are 21 columns within each data file. The first 2 columns pertain to back trajectory parameters: the trajectory number (which is always 1) and the meteorological grid number. The next 9 columns pertain to spatiotemporal information: the year, month, day, hour (0-23), and minute of the trajectory, the previous time of the trajectory (in negative hours), and the airmass location (latitude, longitude, and height in m AGL). The rest of the parameters within each file pertains to surface and meteorological characteristics of the airmass: pressure (in hPa), potential temperature (in K), temperature (in K), precipitation rate (in mm/hr), mixing depth (in m), relative humidity (in % relative to liquid water), specific humidity (in g/kg), H2O mixing ratio (in g/kg), underlying terrain height (in meters above sea level), and incoming radiation (in W/m^2).
This dataset provides continuous near ground-level in situ ozone and meteorological data at the TBS site (S7) during the CoURAGE summer IOP. The ozone inlet and the weather station were approximately 5 meters above the surface. In situ ozone (ppbv) was collected with a 2BTech Model 205 dual beam ozone monitor. The meteorological data (temperature, pressure, relative humidity, wind speed, and wind direction) was collected with an AIRMAR 220WX WeatherStation Instrument with relative humidity (RH) module. The data has 2-second temporal resolution.
An electromagnetic flowmeter has been adjusted to minimize the errors inherent in measuring the flow of low conductivity fluids. This is done through use of a direct-coupled, differential cathode follower, whose grid potential is adjustable with respect to ground levels.
Analytical method for predicting lift and drag for slender sharp-edge delta wings near ground level
Solar electromagnetic radiation spectral distribution from ground level, rocket and satellite observations to obtain value of energy received at top of atmosphere
Visible solar hemisphere circumstances for 28 January 1967 and ground level cosmic rays enhancement not preceded by intense H alpha flares
Decreased resistance to infections initiated by respiratory challenge with Klebsiella pneumoniae or influenza virus was observed in mice maintained in a simulated space cabin environment represented by 98% oxygen atmosphere and 27,000 ft altitude (5 psi). The reduced resistance was manifested by increased mortality rates as compared to those seen in mice maintained at ground level condition. However, an adaptation to the stress appeared to be present in mice exposed to the space cabin environment for extended time period, i.e. 36 days, and then challenged with the influenza virus. Reduced resistance was not observed when Salmonella typhimurium was used as the challenge agent. Histopathologic examination of lungs of mice indicated that the severity of damage appeared to be related to the duration of exposure to the simulated space cabin environment.
The properties of sferics (the electric and magnetic fields generated by electrified clouds and lightning flashes) are briefly surveyed; the source disturbance and the influence of propagation being examined. Methods of observing sferics and their meteorological implications are discussed. It is concluded that close observations of electrostatic and radiation fields are very informative, respectively, upon the charge distribution and spark processes in a cloud; that ground-level sferics stations can accurately locate the positions of individual lightning flashes and furnish valuable knowledge on the properties of the discharges; but that satellite measurements only provide general information on the level of thundery activity over large geographical regions.
Two insulation systems for tanks containing liquid methane in supersonic cruise-type aircraft were designed and tested after an extensive materials investigation. One system is an external insulation and the other is an internal wet-type insulation system. Tank volume was maximized by making the tank shape approach a rectangular parallelopiped. One tank was designed to use the external insulation and the other tank to use the internal insulation. Performance of the external insulation system was evaluated on a full-scale tank under the temperature environment of -320 F to 700 F and ambient pressures of ground-level atmospheric to 1 psia. Problems with installing the internal insulation on the test tank prevented full-scale evaluation of performance; however, small-scale testing verified thermal conductivity, temperature capability, and installed density.
To test the feasibility of remotely measuring the albedos of terrestrial surfaces from photographic images, an inquiry was carried out at ground level using several representative common surface targets. Problems of making such measurements with a spectrally selective sensor, such as photographic film, have been compared to previous work utilizing silicon cells. Two photographic approaches have been developed: a multispectral method which utilizes two or three photographic images made through conventional multispectral filters and a single shot method which utilizes the broad spectral sensitivity of black and white infrared film. Sensitometry related to the methods substitutes a Log Albedo scale for the conventional Log Exposure for creating characteristic curves. Certain constraints caused by illumination goemetry are discussed.
It had been found in previous investigations that hatchability of fertile chicken eggs is reduced to 50% or less of controls if incubation takes place in a low nitrogen atmosphere containing He. Although these results suggest some role for nitrogen in embryogenesis, it is possible that a requirement exists for an inert molecule closer in physical characteristics to nitrogen than is He. An investigation is conducted involving incubation at ground level pressure in a gas mixture in which the 79% inert component was either neon or argon. The effect of varying combinations of nitrogen, helium, and oxygen was also studied.
Research carried out over a number of years has indicated the feasibility of monitoring global air pollution from orbiting satellites. Optical methods show considerable promise of measuring the burdens of pollution, both gaseous and particulates. Important pollution gases, such as sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone, as well as some hydrocarbon vapors, appear amenable to optical remote sensing. Satellite platforms for carrying out this work would not compete with ground monitoring stations but rather supplement them with a different type of data which could be integrated with ground level measurements to provide an all-embracing picture of pollution buildup, mass migration, and dissipation.
Evacuation areas for accidental spills of toxic propellants along rail and highway shipping routes are defined to help local authorities reduce risks to people from excessive vapor concentrations. These criteria along with other emergency information are shown in propellant spill cards. The evacuation areas are based on current best estimates of propellant evaporation rates from various areas of spill puddles. These rates are used together with a continuous point-source, bi-normal model of plume dispersion. The rate at which the toxic plume disperses is based on a neutral atmospheric condition. This condition, which results in slow plume dispersion, represents the widest range of weather parameters which could occur during the day and nighttime periods. Evacuation areas are defined by the ground level boundaries of the plume within which the concentrations exceed the toxic Threshold Limit Value (TLV) or in some cases the Emergency Exposure Limit (EEL).
Analysis of the different behavior of a double magnetic disturbance in November 1971, as observed by Explorer 45, and in December 1971, as shown by ground level magnetic observations. The time sequence of magnetic storm inflation in the evening quadrant of the magnetosphere, as determined by both series of observations, is used as the criterion of the analysis. Particular attention is given to the various phases of proton penetration into the evening quadrant of the magnetosphere during the magnetic disturbance.
Evaluation of photographic and thermal infrared imagery acquired at an altitude of 11,500 ft above ground level (in southwestern South Dakota) on Oct. 15, 1970, June 30, 1971, and Aug. 2, 1971, for use in mapping range sites and soils. A density slicing system was used to enhance film optical density differences associated with range sites and soils. The range site boundaries in native rangeland areas were found to be delineated best by a density slicing analysis of color infrared film obtained in August 1971. The range site maps produced by density slicing were superior to existing range inventory maps. The density slicing analysis of color infrared film from the August 1971 flight was best for locating soil boundaries in rangeland areas. To adequately map soils in rangeland areas, data based on density slicing used in conjunction with slope gradient information derived from stereoscopic analyses provided more detailed and accurate information than is presently available from range site and soil maps of the area.