scholarly journals Inter-comparison study of atmospheric <sup>222</sup>Rn and <sup>222</sup>Rn progeny monitors

2019 ◽  
Author(s):  
Claudia Grossi ◽  
Olivier Llido ◽  
Felix R. Vogel ◽  
Victor Kazan ◽  
Alessandro Capuana ◽  
...  
Keyword(s):  
Atmospheric Aerosol ◽  
Noble Gas ◽  
Measurement Techniques ◽  
Ground Level ◽  
Atmospheric Temperature ◽  
Daily Basis ◽  
Sampling Height ◽  
Radon Monitor ◽  
Radon Variability ◽  
Atmospheric Radon

Abstract. The use of the noble gas radon (222Rn) as tracer for different research studies, for example observation-based estimation of greenhouse gas (GHG) fluxes, has led to the need of high-quality 222Rn activity concentration observations with high spatial and temporal resolution. So far a robust metrology chain for these measurements is not yet available. A 3-month inter-comparison campaign of atmospheric 222Rn and 222Rn progeny monitors based on different measurement techniques was realized during the fall and winter of 2016-2017 to evaluate: i) calibration and correction factors between monitors necessary to harmonize the atmospheric radon observations; and ii) the dependence of each monitor’s response in relation to the sampling height, meteorological and atmospheric aerosol conditions. Results of this study have shown that: i) all monitors were able to reproduce the atmospheric radon variability on daily basis; ii) linear regression fits between the monitors exhibited slopes between 0.62 and 1.17 and offsets ranging between −0.85 Bq m−3 and −0.23 Bq m−3 when sampling 2 m above ground level (a.g.l.). Corresponding results at 100 m a.g.l. exhibited slopes of 0.94 and 1.03 with offsets of −0.13 Bq m−3 and 0.01 Bq m−3, respectively; iii) no influence of atmospheric temperature and relative humidity on monitor responses was observed for unsaturated conditions; and iv) changes of the ratio between radon progeny and radon monitor responses were observed under very high atmospheric humidity and under very low atmospheric aerosol concentrations. However, a more statistically robust evaluation of these last influences based on a longer dataset should be conducted to improve the harmonization of the data.

scholarly journals Intercomparison study of atmospheric <sup>222</sup>Rn and <sup>222</sup>Rn progeny monitors

2020 ◽  
Vol 13 (5) ◽  
pp. 2241-2255
Author(s):  
Claudia Grossi ◽  
Scott D. Chambers ◽  
Olivier Llido ◽  
Felix R. Vogel ◽  
Victor Kazan ◽  
...  
Keyword(s):  
Atmospheric Aerosol ◽  
Noble Gas ◽  
Measurement Techniques ◽  
Ground Level ◽  
Atmospheric Temperature ◽  
Daily Basis ◽  
Correction Factors ◽  
Sampling Height ◽  
Intercomparison Study ◽  
Atmospheric Radon

Abstract. The use of the noble gas radon (222Rn) as a tracer for different research studies, for example observation-based estimation of greenhouse gas (GHG) fluxes, has led to the need of high-quality 222Rn activity concentration observations with high spatial and temporal resolution. So far a robust metrology chain for these measurements is not yet available. A portable direct atmospheric radon monitor (ARMON), based on electrostatic collection of 218Po, is now running at Spanish stations. This monitor has not yet been compared with other 222Rn and 222Rn progeny monitors commonly used at atmospheric stations. A 3-month intercomparison campaign of atmospheric 222Rn and 222Rn progeny monitors based on different measurement techniques was realized during the fall and winter of 2016–2017 to evaluate (i) calibration and correction factors between monitors necessary to harmonize the atmospheric radon observations and (ii) the dependence of each monitor's response in relation to the sampling height and meteorological and atmospheric aerosol conditions. Results of this study have shown the following. (i) All monitors were able to reproduce the atmospheric radon variability on a daily basis. (ii) Linear regression fits between the monitors exhibited slopes, representing the correction factors, between 0.62 and 1.17 and offsets ranging between −0.85 and −0.23 Bq m−3 when sampling 2 m above ground level (a.g.l.). Corresponding results at 100 m a.g.l. exhibited slopes of 0.94 and 1.03 with offsets of −0.13 and 0.01 Bq m−3, respectively. (iii) No influence of atmospheric temperature and relative humidity on monitor responses was observed for unsaturated conditions at 100 m a.g.l., whereas slight influences (order of 10−2) of ambient temperature were observed at 2 m a.g.l. (iv) Changes in the ratio between 222Rn progeny and 222Rn monitor responses were observed under very low atmospheric aerosol concentrations. Results also show that the new ARMON could be useful at atmospheric radon monitoring stations with space restrictions or as a mobile reference instrument to calibrate in situ 222Rn progeny monitors and fixed radon monitors. In the near future a long-term comparison study between ARMON, HRM, and ANSTO monitors would be useful to better evaluate (i) the uncertainties of radon measurements in the range of a few hundred millibecquerels per cubic meter to a few becquerels per cubic meter and (ii) the response time correction of the ANSTO monitor for representing fast changes in the ambient radon concentrations.

High efficiency and portable monitor of atmospheric radon concentration activity for environmental applications

2021 ◽  
Author(s):  
Roger Curcoll Masanes ◽  
Claudia Grossi ◽  
Arturo Vargas
Keyword(s):  
Radon Concentration ◽  
High Efficiency ◽  
Atmospheric Transport ◽  
Noble Gas ◽  
Measurement Techniques ◽  
High Sensitivity ◽  
Lower Atmosphere ◽  
Environmental Applications ◽  
New Instrument ◽  
Atmospheric Radon

&lt;p&gt;The natural radioactive noble gas radon (&lt;sup&gt;222&lt;/sup&gt;Rn) is originated from the decay of radium into the soil and then continuously exhaled to the lower atmosphere. Its diffusion and exhalation rate depend both on the physical and environmental conditions of the soil layers and on the meteorological conditions. With a half-life of 3.8 days and a very limited chemical activity, the &lt;sup&gt;222&lt;/sup&gt;Rn is nowadays being used as an atmospheric tracer for: i) the improvement of atmospheric transport models used, among others, to identify greenhouse gas (GHG) emission sources; ii) for the indirect estimation of GHG fluxes by the Radon Tracer Method (RTM). These previous applications need high sensitivity and precision at low radon concentrations range (&lt; 100 Bq m&lt;sup&gt;-3&lt;/sup&gt;).&lt;/p&gt;&lt;p&gt;A new monitor, based on alpha spectrometry of &lt;sup&gt;218&lt;/sup&gt;Po electrostatically collected on a PIPs detector, has been designed and developed at the Institute of Energy Technologies (INTE) of the Universitat Politecnica de Catlunya (UPC)&amp;#160; in the mark of the project &amp;#8216;High efficiency monitor of atmospheric radon concentration for radiation protection and environmental applications (MARE&lt;sup&gt;2&lt;/sup&gt;EA), reference: 2019-LLAV-00035, funded by the Catalan Agency for Management of University and Research Grants. The aim is building an instrument able to measure atmospheric radon concentration activities with high precision in order to be running at GHG atmospheric networks for the RTM applications.&lt;/p&gt;&lt;p&gt;The monitor is an improved version of a previous prototype instrument (Grossi et al., 2012, 2020). The new instrument will allow a higher efficiency, robustness and portability. In addition, it will have a GUI interface to be user friendly. Finally, in order to reduce the air sample humidity within the detection volume of the instrument which affects the &lt;sup&gt;218&lt;/sup&gt;Po collection, a portable drying system has also been built to keep the instrument ongoing without maintenance during several weeks.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;&lt;strong&gt;References&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Grossi, C., Arnold, D., Adame, J. A., L&amp;#243;pez-Coto, I., Bol&amp;#237;var, J. P., De La Morena, B. A., &amp; Vargas, A. (2012). Atmospheric 222Rn concentration and source term at El Arenosillo 100 m meteorological tower in southwest Spain. Radiation Measurements, 47(2), 149&amp;#8211;162. https://doi.org/10.1016/j.radmeas.2011.11.006&lt;/p&gt;&lt;p&gt;Grossi, C., Chambers, S. D., Llido, O., Vogel, F. R., Kazan, V., Capuana, A., Werczynski, S., Curcoll, R., Delmotte, M., Vargas, A., Morgu&amp;#237;, J.-A., Levin, I., &amp; Ramonet, M. (2020). Intercomparison study of atmospheric &lt;sup&gt;222&lt;/sup&gt;Rn and &lt;sup&gt;222&lt;/sup&gt;Rn progeny monitors. Atmospheric Measurement Techniques, 13(5). https://doi.org/10.5194/amt-13-2241-2020&lt;/p&gt;

The excitation of atmospheric oscillations

1963 ◽  
Vol 274 (1356) ◽  
pp. 91-121 ◽  
Keyword(s):  
Large Scale ◽  
Ground Level ◽  
Atmospheric Temperature ◽  
Direct Absorption ◽  
Pressure Oscillations ◽  
Thermal Mechanism ◽  
Atmospheric Temperature Profile ◽  
Water Vapour Absorption ◽  
The Vertical Distribution ◽  
Quiet Day

An investigation is made into the excitation of large-scale atmospheric oscillations by the direct absorption of incoming solar radiation by atmospheric ozone. The atmospheric temperature profile is chosen to agree favourably with the main features of the observed temperature distribution, particularly as regards the maximum around the 50 km height; this distribution is shown to be non-resonant as far as the solar semidiurnal component is concerned. The excited solar diurnal, semidiurnal and terdiurnal pressure oscillations are computed and we find that although the largest Fourier component in the heating is the diurnal term , the tide it excites is small in keeping with observation. On the other hand, the excited semidiurnal oscillation is much larger than that due to any previously considered thermal mechanism . It is found that the main semidiurnal and terdiurnal tides generated by the direct absorption of insolation by ozone as calculated in the present work, together with published results regarding water vapour absorption, can adequately account for the observed values at ground level. The seasonal variations of the semi and terdiurnal tides are also calculated and these agree extremely well with observation. Finally, the change of phase of 180° in the vertical distribution of the solar semidiurnal oscillation, which is expected from the analysis of the quiet day magnetic variation, is accounted for in the present work.

scholarly journals Nanoparticle Behaviour in an Urban Street Canyon at Different Heights and Implications on Indoor Respiratory Doses

Atmosphere ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 772 ◽  
Author(s):  
Manigrasso ◽  
Protano ◽  
Vitali ◽  
Avino
Keyword(s):  
Street Canyon ◽  
Ultrafine Particles ◽  
Ground Level ◽  
Daily Basis ◽  
Total Daily Dose ◽  
Indoor Environments ◽  
Size Distributions ◽  
Ground Floor ◽  
Urban Street ◽  
Indoor Aerosol

The amount of outdoor particles that indoor environments receive depends on the particle infiltration factors (Fin), peculiar of each environment, and on the outdoor aerosol concentrations and size distributions. The respiratory doses received, while residing indoor, will change accordingly. This study aims to ascertain to what extent such doses are affected by the vertical distance from the traffic sources. Particle number size distributions have been simultaneously measured at street level and at about 20 m height in a street canyon in downtown Rome. The same Fin have been adopted to estimate indoor aerosol concentrations, due to the infiltration of outdoor particles and then the relevant daily respiratory doses. Aerosol concentrations at ground floor were more than double than at 20 m height and richer in ultrafine particles. Thus, although aerosol infiltration efficiency was on average higher at 20 m height than at ground floor, particles more abundantly infiltrated at ground level. On a daily basis, this involved a 2.5-fold higher dose at ground level than at 20 m height. At both levels, such doses were greater than those estimated over the period of activity of some indoor aerosol sources; therefore, they represent an important contribution to the total daily dose.

ATMOSPHERIC CONTRIBUTION TO THE DIURNAL VARIATION OF THE COSMIC-RAY MESON INTENSITY AT DEEP RIVER

1966 ◽  
Vol 44 (6) ◽  
pp. 1329-1347 ◽  
Author(s):  
M. Bercovitch
Keyword(s):  
Diurnal Variation ◽  
Neutron Monitor ◽  
Cosmic Ray ◽  
Ground Level ◽  
Barometric Pressure ◽  
Atmospheric Temperature ◽  
The Mean ◽  
Variation Vector ◽  
Best Fit ◽  
Ground Level Air

We have established the correlation between the atmospheric temperature contribution to the diurnal variation observed by a meson monitor at Deep River and the diurnal variation of two easily and continuously observable atmospheric variables, the ground-level air temperature and the barometric pressure. The atmospheric meson diurnal variation vector is taken to be, on a statistical basis, A = M−RN, where M and N represent the observed meson-monitor and neutron-monitor diurnal variations and R is the factor of proportionality between the meson and neutron monitor responses to the primary anisotropy. It is found that A is proportional in amplitude to T, the ground-level temperature diurnal variation, and, further, that T and the barometric-pressure diurnal variation P are proportional in amplitude. The "best-fit" representation of A in terms of T and P is determined by minimizing the mean-square deviation between the daily vectors RN and (M−A). Where A = CtT + CpP, the best fit occurs when Ct = −0.0052%/ °C, Cp = 0.038%/mb, R = 0.47, and the phase of T is shifted by + 1.0 hour. These values apply to Deep River, where the original hourly meson data have been barometer-corrected using a coefficient of 0.16%/mb.

scholarly journals Emerging Ultrasound Technologies for Early Markers of Disease

2002 ◽  
Vol 18 (5-6) ◽  
pp. 249-268 ◽  
Author(s):  
Ernest J. Feleppa ◽  
S. Kaisar Alam ◽  
Cheri X. Deng
Keyword(s):  
Imaging Modality ◽  
Measurement Techniques ◽  
Daily Basis ◽  
Macroscopic Anatomy ◽  
Clinical Imaging ◽  
Independent Information ◽  
Early Markers ◽  
Conventional Ultrasound ◽  
Evaluation And Monitoring ◽  
Flow Detection

Ultrasound has been a popular clinical imaging modality for decades. It is well established as a means of displaying the macroscopic anatomy of soft-tissue structures. While conventional ultrasound methodologies (i.e., B-mode and Doppler methods) are well proven and continue to advance technically on a daily basis, e.g. by extending into higher frequencies and taking advantage of harmonic phenomena in tissues, fundamentally new ultrasound technologies also are emerging and offer exciting promise for making significant improvements in the clinical imaging of disease. These emerging methods include spectrum analysis, elasticity imaging, contrast-agent methods, and advanced flow detection and measurement techniques. Each provides independent information and, used alone, each can provide powerful new imaging capabilities; combined with each other, their capabilities may be even greater in many applications; and all in principle can be used in concert with other imaging modalities to offer the possibility of further improvements in disease detection, evaluation, and monitoring.

scholarly journals Atmospheric sub-3 nm particles at high altitudes

2009 ◽  
Vol 9 (5) ◽  
pp. 19435-19470 ◽  
Author(s):  
S. Mirme ◽  
A. Mirme ◽  
A. Minikin ◽  
A. Petzold ◽  
U. Hõrrak ◽  
...  
Keyword(s):  
Atmospheric Aerosol ◽  
Aerosol Particles ◽  
Particle Diameter ◽  
Ground Level ◽  
Atmospheric Particles ◽  
Aerosol Formation ◽  
Upper Troposphere ◽  
Ion Clusters ◽  
Almost All ◽  
Atmospheric Clusters

Abstract. Formation of new atmospheric aerosol particles is known to occur almost all over the world and the importance of these particles to climate and air quality has been recognized. Recently, it was found that atmospheric aerosol formation begins at particle diameter of around 1.5–2.0 nm and a pool of sub-3 nm atmospheric particles – consisting of both charged and uncharged ones – was observed at the ground level. Here, we report on the first airborne observations of the pool of sub-3 nm neutral atmospheric particles. Between 2 and 3 nm, their concentration is roughly two orders of magnitude larger than that of the ion clusters, depending slightly on the altitude. Our findings indicate that new particle formation takes place actively throughout the tropospheric column up to the tropopause. Particles were found to be formed via neutral pathways in the boundary layer, and there was no sign of an increasing role by ion-induced nucleation toward the upper troposphere. Clouds, while acting as a source of sub-10 nm ions, did not perturb the overall budget of atmospheric clusters or particles.

scholarly journals Formaldehyde total column densities over Mexico City: comparison between MAX-DOAS and solar absorption FTIR measurements

2020 ◽  
Author(s):  
Claudia Rivera Cárdenas ◽  
Cesar Guarín ◽  
Wolfgang Stremme ◽  
Martina M. Friedrich ◽  
Alejandro Bezanilla ◽  
...  
Keyword(s):  
Mexico City ◽  
Measurement Techniques ◽  
Mixing Layer ◽  
Ground Level ◽  
Urban Site ◽  
Optical Absorption Spectroscopy ◽  
Vertical Column ◽  
Solar Absorption ◽  
Diurnal Variability ◽  
Total Column

Abstract. Formaldehyde (HCHO) total column densities over the Mexico City Metropolitan Area (MCMA) were retrieved using two independent measurement techniques: Multi Axis – Differential Optical Absorption Spectroscopy (MAX-DOAS) and Fourier Transform Infrared (FTIR) Spectroscopy. For the MAX-DOAS measurements, the software QDOAS was used to calculate differential Slant Column Densities (dSCDs) from the measured spectra and subsequently the Mexican MAX-DOAS Fit retrieval code (MMF) to convert from dSCDs to Vertical Column Densities (VCDs). The direct-solar absorption spectra measured with FTIR were analyzed using the PROFFIT retrieval code. Typically the MAX-DOAS instrument reports higher VCDs than those measured with FTIR, in part due to differences found in the ground-level sensitivities as revealed from the retrieval diagnostics from both instruments. Three MAX-DOAS datasets using measurements conducted towards the east, west or both sides of the measurement plane were evaluated with respect to the FTIR results. The retrieved MAX-DOAS HCHO VCDs where 5 %, 9 % and 28 % larger than the FTIR which, supported with satellite data, could demonstrate a large horizontal inhomogeneity in the HCHO abundances. A time-dependent comparison revealed that the vertical distribution of this pollutant, guided by the evolution of the mixing layer height, can play an important role in how the results are affected. Apart from the reported seasonal and diurnal variability of HCHO columns within the urban site, background data from measurements at a high-altitude station, located only 60 km away are presented.

scholarly journals Determining the Performance Measurement of SME from Economic Value Added: Study on Hungary, Somogy County

2018 ◽  
Vol 18(33) (2) ◽  
pp. 270-279
Author(s):  
Devesh Singh ◽  
Zoltan Gal ◽  
Raqif Huseynov ◽  
Michał Wojtaszek
Keyword(s):  
Economic Value ◽  
Value Added ◽  
High Growth ◽  
Ground Level ◽  
Daily Basis ◽  
Economic Value Added ◽  
Analysis Method ◽  
Industrial Growth ◽  
Policy Makers ◽  
High Skill

EVA (Economic Value Added) permits commercial businesses to figure out whether the business is operating in profit and the money can be put into effect into a more profitable source. A leading EVA is a sign that the company has a greater value. The goal of this study is to identify if SMEs' actions carried out on a daily basis are able to generate economic value added for their business. The study is based on a comparative study between Hungary and 28 EU countries. The study is carried out in Hungary’s region of Somogy county. First, the variables for research were created and research was carried out at ground level. The research used the Expletory Factor analysis method to find EVA determinants. The results showed that determinants work together to reshape the regional industrial growth. The research demonstrated that finance and sluggish production are the major determinants in Somogy county. Entrepreneurs' skills and finance have the major impact, which means that to achieve a high growth in SMEs, policy makers have to solve these two problems and make the policy concentric toward finance and high skill development problem.

scholarly journals Thermodynamic model for a pilot balloon

2021 ◽  
Author(s):  
Vicent Favà ◽  
Juan José Curto ◽  
Alba Gilabert
Keyword(s):  
Thermodynamic Model ◽  
Ground Level ◽  
Atmospheric Temperature ◽  
Lapse Rate ◽  
Temperature Lapse Rate ◽  
Ascent Rate ◽  
Pilot Balloon ◽  
The Us ◽  
Optical Theodolite

Abstract. In the early part of the 20th century, tracking a pilot balloon from the ground with an optical theodolite was one of the few methods that was able to provide information from the upper air. One of the most significant sources of error with this method, however, was involved in calculating the balloon height as a function of time, a calculation dependent on the ascent rate which was traditionally taken to be constant. This study presents a new thermodynamic model which allows us to compute the thermal jump between the surrounding environment and the lifting gas as a function of different parameters such as the atmospheric temperature lapse rate or the physical characteristics of the balloon. The size of the thermal jump and its effect on the ascent rate is discussed for a 30 g pilot balloon, which was the type used at the Ebro Observatory (EO) between 1952 and 1963. The meridional and zonal components of the wind profile from ground level up to 10 km altitude were computed by applying the model using EO digitized data for a sample of this period. The obtained results correlate very well with those obtained from the ERA5 reanalysis. A very small thermal jump with a weak effect on the computed ascent rate was found. This ascent rate is consistent with the values assigned in that period to the balloons filled with hydrogen used at the Ebro Observatory and to the 30 g balloons filled with helium used by the US National Weather Service.

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