scholarly journals DIURNAL AND SPATIAL VARIATIONS OF RADON CONCENTRATION AND ITS INFLUENCE ON IONIZATION OF AIR

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Zdenka Stojanovska ◽  
Predrag Kolarž ◽  
Zoran Ćurguz ◽  
Zora S. Žunić
Keyword(s):  
Radon Concentration ◽  
Lower Layer ◽  
Health Hazard ◽  
Inversion Layer ◽  
Atmospheric Electricity ◽  
Temperature Inversion ◽  
Spatial Variations ◽  
Alpha Emitter ◽  
Radon Monitor ◽  
The Difference

The most abundant and efficient source of air ionization in the lower layer of the atmosphere is radon. As an alpha emitter, radon plays a crucial role in the earth's atmospheric electricity. Besides the physical, radon and ions have a significant biological role concerning human health: radon is a health hazard while the ions are beneficial ingredients of the air we breathe. In this study, we examined the dynamics of radon and air ions diurnal change in houses with different floor and windows insulations. Measurements were made using continual radon monitor Rad-7 and air ion counter CDI-06. Diurnal and spatial variations of both atmospheric constituents are mutually related and dependent mostly on radon exhalation potential, meteorological parameters, aerosol concentration and formation of the temperature inversion layer. Indoor concentrations are related to the potential for accumulation of radon that is coming from the ground beneath the foundation and also influenced by external radon concentration that is diffusing through the walls, doors, and windows. Level of diffusion is depending on insulation. The difference in the paths by which radon enters the home can be seen by analyzing changes during diurnal continuous measurements.

scholarly journals Mesospheric bores at southern midlatitudes observed by ISS-IMAP/VISI: a first report of an undulating wave front

2018 ◽  
Vol 18 (22) ◽  
pp. 16399-16407 ◽  
Author(s):  
Yuta Hozumi ◽  
Akinori Saito ◽  
Takeshi Sakanoi ◽  
Atsushi Yamazaki ◽  
Keisuke Hosokawa
Keyword(s):  
Wave Front ◽  
Large Scale ◽  
Near Infrared ◽  
Inversion Layer ◽  
Space Station ◽  
Temperature Inversion ◽  
Wide Field ◽  
Broadband Emission ◽  
The Difference ◽  
Spectral Imager

Abstract. Large-scale spatial structures of mesospheric bores were observed by the Visible and near-Infrared Spectral Imager (VISI) of the ISS-IMAP mission (Ionosphere, Mesosphere, upper Atmosphere and Plasmasphere mapping mission from the International Space Station) in the mesospheric O2 airglow at 762 nm wavelength. Two mesospheric bore events in southern midlatitudes are reported in this paper: one event at 48–54∘ S, 10–20∘ E on 9 July 2015 and the other event at 35–43∘ S, 24∘ W–1∘ E on 7 May 2013. For the first event, the temporal evolution of the mesospheric bore was investigated from the difference of two observations in consecutive passes. The estimated eastward speed of the bore is 100 m s−1. The number of trailing waves increased with a rate of 3.5 waves h−1. Anticlockwise rotation with a speed of 20∘ h−1 was also recognized. These parameters are similar to those reported by previous studies based on ground-based measurements, and the similarity supports the validity of VISI observation for mesospheric bores. For the second event, VISI captured a mesospheric bore with a large-scale and undulating wave front. The horizontal extent of the wave front was 2200 km. The long wave front undulated with a wavelength of 1000 km. The undulating wave front is a new feature of mesospheric bores revealed by the wide field of view of VISI. We suggest that nonuniform bore propagating speed due to inhomogeneous background ducting structure might be a cause of the undulation of the wave front. Temperature measurements from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) onboard the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) satellite indicated that bores of both events were ducted in a temperature inversion layer.

scholarly journals Long-term Lidar Observations of the Gravity Wave Activity near the Mesopause at Arecibo

2018 ◽  
Author(s):  
Xianchang Yue ◽  
Jonathan S. Friedman ◽  
Qihou Zhou ◽  
Xiongbin Wu ◽  
Jens Lautenbach
Keyword(s):  
Potential Energy ◽  
Gravity Wave ◽  
Inversion Layer ◽  
Lower Thermosphere ◽  
Temperature Inversion ◽  
Temperature Structure ◽  
Mean Temperature ◽  
The Mean ◽  
Highly Correlated ◽  
Lidar Observations

Abstract. 11-years long K Doppler lidar observations of temperature profiles in the mesosphere and lower thermosphere (MLT) between 85 and 100 km, conducted at the Arecibo Observatory, Puerto Rico (18.35° N, 66.75° W), are used to estimate seasonal variations of the mean temperature, the squared Brunt-Väisälä frequency, and the gravity wave potential energy in a composite year. The following unique features are obtained: (1) The mean temperature structure shows similar characteristics as a prior report based on a smaller dataset: (2) The profiles of the squared Brunt-Väisälä frequency usually reach the maxima at or just below the temperature inversion layer when that layer is present. The first complete range-resolved climatology of potential energy of temperature fluctuations in the tropical MLT exhibits an altitude dependent combination of annual oscillation (AO) and semiannual oscillation (SAO). Between 88 to 96 km altitude, the amplitudes of AO and SAO are comparable, and their phases are almost the same and quite close to day of year (DOY) 100. Below 88 km, the SAO amplitude is significantly larger than AO and the AO phase shifts to DOY 200 and after. At 97 to 98 km altitude, the amplitudes of AO and SAO reach their minima, and both phases shift significantly. Above that, the AO amplitude becomes greater. The annual mean potential energy profile reaches the minimum at 91 to 92 km altitude. The altitude-dependent SAO of the potential energy is found to be highly correlated with the satellite observed mean zonal winds reported in the literature.

RADON CONCENTRATION IN SOIL AND GROUNDWATER OF WEST COASTAL AREA, BANGLADESH

2020 ◽  
Vol 191 (3) ◽  
pp. 341-348
Author(s):  
Farah Deeba ◽  
Syed Hafizur Rahman ◽  
Mohammad Zafrul Kabir
Keyword(s):  
Ground Water ◽  
Coastal Area ◽  
Radon Concentration ◽  
Annual Effective Dose ◽  
Mean Value ◽  
Natural Background ◽  
Safe Limit ◽  
Radon Monitor ◽  
Different Depths ◽  
The Mean

Abstract On-site radon concentration has been measured in soil gas and ground water using AlphaGUARD PQ2000 PRO (Saphymo, Germany) radon monitor at the west coastal area of Bangladesh. The measured radon concentration in ground water samples is in the range of 1.41 ± 0.29 to 3.2 ± 0.59 Bq/l with the mean value of 2.33 ± 0.50 Bq/l, which lies within the safe limit recommended by UNSCEAR (2008). The total annual effective dose estimated due to radon concentration in ground water ranges from 3.85 to 8.74 μSv/y with the mean value of 6.37 μSv/y, which is lower than the safe limit set by WHO (2004) and EU (1998). In soil samples, radon concentration has been measured at three different depths (0, 20 and 40 cm) in each location. The highest and the lowest concentrations are 4790 ± 51 and 10 ± 04 Bq/m3 at 40 and 0 cm (surface) depth, respectively, which lie within the natural background levels.

Observation and analysis of the temperature inversion layer by Raman lidar up to the lower stratosphere

2015 ◽  
Vol 54 (34) ◽  
pp. 10079 ◽  
Author(s):  
Yufeng Wang ◽  
Xiaoming Cao ◽  
Tingyao He ◽  
Fei Gao ◽  
Dengxin Hua ◽  
...  
Keyword(s):  
Lower Stratosphere ◽  
Inversion Layer ◽  
Temperature Inversion ◽  
Raman Lidar

scholarly journals Evaluation of Polar WRF from Modeling the Atmospheric Boundary Layer over Antarctic Sea Ice in Autumn and Winter

2012 ◽  
Vol 140 (12) ◽  
pp. 3919-3935 ◽  
Author(s):  
Esa-Matti Tastula ◽  
Timo Vihma ◽  
Edgar L Andreas
Keyword(s):  
Boundary Layer ◽  
Sea Ice ◽  
Surface Temperature ◽  
Atmospheric Boundary Layer ◽  
Inversion Layer ◽  
Temperature Inversion ◽  
Heat Fluxes ◽  
Poor Correlation ◽  
Antarctic Sea Ice ◽  
Autumn And Winter

Abstract Regional simulations of the atmospheric boundary layer over Antarctic sea ice that have been adequately validated are rare. To address this gap, the authors use the doubly nested Polar Weather Research and Forecasting (Polar WRF) mesoscale model to simulate conditions during Ice Station Weddell (ISW) in the austral autumn and winter of 1992. The WRF simulations test two boundary layer schemes: Mellor–Yamada–Janjic and the Asymmetric Convective Model. Validation is against surface-layer and sounding observations from ISW. Simulated latent and sensible heat fluxes for both boundary layer schemes had poor correlation with the observed fluxes. Simulated surface temperature had better correlation with the observations, with a typical bias of 0–2 K and a root-mean-square error of 6–7 K. For surface temperature and wind speed, the Polar WRF yielded better results than the ECMWF Re-Analysis Interim (ERA-Interim). A more challenging test of the simulations is to reproduce features of the low-level jet and the temperature inversion, which were observed, respectively, in 80% and 96% of the ISW radiosoundings. Both boundary layer schemes produce only about half as many jets as were observed. Moreover, the simulated jet coincided with an observed jet only about 30% of the time. The number of temperature inversions and the height at the inversion base were better reproduced, although this was not the case with the depth of the inversion layer. Simulations of the temperature inversion improved when forecasts of cloud fraction agreed to within 0.3 with observations. The modeled inversions were strongest when the incoming longwave radiation was smallest, but this relationship was not observed at ISW.

scholarly journals Methodology for determining multilayered temperature inversions

2015 ◽  
Vol 8 (5) ◽  
pp. 2051-2060 ◽  
Author(s):  
G. J. Fochesatto
Keyword(s):  
Temperature Profile ◽  
Large Scale ◽  
Error Function ◽  
Inversion Layer ◽  
Lower Troposphere ◽  
Temperature Inversion ◽  
Linear Interpolation ◽  
Pollution Dispersion ◽  
Thermal Inversion ◽  
Temperature Inversions

Abstract. Temperature sounding of the atmospheric boundary layer (ABL) and lower troposphere exhibits multilayered temperature inversions specially in high latitudes during extreme winters. These temperature inversion layers are originated based on the combined forcing of local- and large-scale synoptic meteorology. At the local scale, the thermal inversion layer forms near the surface and plays a central role in controlling the surface radiative cooling and air pollution dispersion; however, depending upon the large-scale synoptic meteorological forcing, an upper level thermal inversion can also exist topping the local ABL. In this article a numerical methodology is reported to determine thermal inversion layers present in a given temperature profile and deduce some of their thermodynamic properties. The algorithm extracts from the temperature profile the most important temperature variations defining thermal inversion layers. This is accomplished by a linear interpolation function of variable length that minimizes an error function. The algorithm functionality is demonstrated on actual radiosonde profiles to deduce the multilayered temperature inversion structure with an error fraction set independently.

scholarly journals The Extratropical Tropopause Inversion Layer: Global Observations with GPS Data, and a Radiative Forcing Mechanism

2007 ◽  
Vol 64 (12) ◽  
pp. 4489-4496 ◽  
Author(s):  
William J. Randel ◽  
Fei Wu ◽  
Piers Forster
Keyword(s):  
Water Vapor ◽  
Radiative Forcing ◽  
Inversion Layer ◽  
Temperature Inversion ◽  
Shortwave Radiation ◽  
Gps Data ◽  
Circulation Types ◽  
High Vertical Resolution ◽  
Extratropical Tropopause ◽  
Balanced Dynamics

Abstract Global characteristics of the extratropical tropopause inversion layer identified in radiosonde observations by Birner are studied using high vertical resolution temperature profiles from GPS radio occultation measurements. The GPS data are organized according to the height of the thermal tropopause in each profile, and a temperature inversion layer above the tropopause (with an average magnitude of 3–5 K) is found to be a ubiquitous, climatological feature. The GPS data show that the inversion layer is present for all seasons in both hemispheres, spanning the subtropics to the pole, and there is not strong longitudinal structure. Dependence of the inversion layer on upper-troposphere vorticity is studied; while anticyclones exhibit a substantially stronger inversion than cyclones (as expected from balanced dynamics), the inversion is evident for all circulation types. Radiative transfer calculations indicate that strong gradients in both ozone and water vapor near the tropopause contribute to the inversion. Significant absorption of both longwave and shortwave radiation by ozone occurs, warming the region above the tropopause. Water vapor near and immediately above the tropopause contributes to cooling, effectively enhancing the inversion.

scholarly journals Sudden narrow temperature-inversion-layer formation in ALOHA-93 as a critical-layer-interaction phenomenon

1998 ◽  
Vol 103 (D6) ◽  
pp. 6323-6332 ◽  
Author(s):  
T. Y. Huang ◽  
H. Hur ◽  
T. F. Tuan ◽  
X. Li ◽  
E. M. Dewan ◽  
...  
Keyword(s):  
Inversion Layer ◽  
Temperature Inversion ◽  
Critical Layer ◽  
Layer Formation ◽  
Layer Interaction ◽  
Interaction Phenomenon
Sign in / Sign up

Export Citation Format

Share Document