Gamma Dose Rate Measurements in Northern Spain: Influence of Local Meteorological Scenarios on Radiological "False Alarms" in a Real-Time Radiological Monitoring Network.

The present study characterizes gamma dose rate (GDR) concentrations in Bilbao, located in the northern Iberian Peninsula, utilizing a comprehensive 10-min interval database spanning from 2009 to 2018. This station belongs to the radiological environmental monitoring of the Basque Country network. The daily average GDR was found to be 0.

Exploring the influence of meteorological conditions on the variability of olive pollen intradiurnal patterns: Differences between pre- and post-peak periods.

Olive trees hold a significant economical, ecological and ornamental value, especially in the Mediterranean area. It is a wind-pollinated species emitting huge quantities of pollen with a high degree of allergenic sensitization. Andalusia region (southern Spain), where 15 % of the global olive tree population is cultivated, present a high density of this crop, reaching daily airborne olive pollen concentrations up to 6.

Local weather phenomenon Galerna influences daily radon concentrations in northern Iberian Peninsula.

One of the main factors that affect urban air quality is meteorology. The objective of this study is to understand and characterise the influence that "Galerna" (GL) (an abrupt westerly change over the northern coast of Spain) has on the daily variability of the air quality over Bilbao city (northern Spain). A total of 46 one-day periods from 2009 to 2019 during which GL have been analysed.

Analysis of Rn Surface Concentrations in the Basque Country (Spain): A Case Study of Heat Waves.

The objective of this study was to characterize radon concentrations registered in the Radiological Surveillance Network of the Basque country in relation to local meteorological parameters, and to determine its behaviour under heatwave events. For this purpose, radon measurements and meteorological parameters from June 2012 to June 2015 were analysed at two sites, Bilbao and Vitoria (northern Spain), in a region characterized by complex orography, causing large temporal and spatial variability in meteorological conditions. Yearly, seasonal, and diurnal cycle differences and similarities were investigated at both sites.

Meteorological Approach in the Identification of Local and Remote Potential Sources of Radon: An Example in Northern Iberian Peninsula.

This paper presents a meteorological approach to identify local and remote sources driving the variability of surface daily radon concentrations. To this purpose, hourly Rn concentration and surface meteorological measurements, and air mass trajectories at Bilbao station (northern Iberian Peninsula) during the period 2017-2018 have been taken as reference. To investigate the potential transport pathways and potential Rn sources, the backward trajectory cluster analysis, trajectory sector analysis (TSA), and potential source contribution function (PSCF) are applied.

16 Years (2006-2021) of Surface Ozone Measurements in Córdoba (Southern Spain): Trends and the Impact of the COVID-19 Lockdown.

Surface ozone concentrations (O) during the period 2006-2021 are analysed at Córdoba city (southern Iberian Peninsula) in suburban and urban sampling sites. The aims are to present the levels and temporal variations, to explore trends and to quantity the variation in O concentrations in the context of the COVID-19 lockdown. The O means are higher in the suburban station (62 µg m and 51.

Airflow and teleconnection patterns driving the spatial and temporal variability of high Be air concentrations in Europe.

The long-term monitoring of the cosmogenic Be activity concentrations has been used to better understand the influence of large-scale atmospheric circulation dynamics in the troposphere. With an aim, this study analyzes weekly Be data from 15 sampling stations in Europe over 2005-2014. We first define peak (or extremely high) events in each station as those activity concentrations above the 90th percentile, and then investigate their temporal and spatial variability.

Analysis of Alpha Activity Levels and Dependence on Meteorological Factors over a Complex Terrain in Northern Iberian Peninsula (2014-2018).

Alpha ambient concentrations in ground-level air were measured weekly in Bilbao (northern Spain) by collecting aerosols in filters between 2014 and 2018. Over this period, the alpha activity concentrations in the aerosol's samples range from 13.9 µBq/m to 246.

Dispersion and ground deposition of radioactive material according to airflow patterns for enhancing the preparedness to N/R emergencies.

The intent of minimizing the impact of the large amount of radioactive material potentially released into the atmosphere in a nuclear event implies preparedness activities. In the early phase and in absence of field observations, countermeasures would largely rely on a previous characterization of the transport and dispersion of radioactive particles and the potential levels of radioactive contamination. This study presents a methodology to estimate the atmospheric transport, dispersion and ground deposition patterns of radioactive particles.

An episode of Ru-106 in air over Europe, September-October 2017 - Geographical distribution of inhalation dose over Europe.

Between the end of September and early October 2017, Ru was recorded by air monitoring stations across parts of Europe. In the environment, this purely anthropogenic radionuclide can be detected very rarely only. As far as known, Ru is only used in radiotherapy and possibly in radiothermal generators.

Analysis of trends, periodicities, and correlations in the beryllium-7 time series in Northern Europe.

The activity concentrations of beryllium-7, a natural radiotracer that is considered as a tracer of the stratospheric-tropospheric exchange, shows a distinct behaviour in Northern Europe compared to the central and southern parts of the continent. In this study, we use the measurements collected at four sampling stations in Scandinavia (Ivalo, Umea, Kista, Risoe) between 2001 and 2010 and investigate their trends, periodicities and residuals with the aim to further understand the common features in the beryllium-7 data records in northern sampling sites. The beryllium-7 activity concentrations exhibit statistically significant positive trends that range from an average value of 1.

Evidences of different meteorological patterns governing Be and Pb surface levels in the southern Iberian Peninsula.

Be, Pb and PM levels in surface air have been simultaneously measured at two sampling sites in the southern Iberian Peninsula for a period of two years. Each site covers one different meteorological area of the Guadalquivir valley, from the mouth (Huelva) to the middle point (Cordoba). The objective of the present study is to analyse the spatial variability of both natural radionuclides, and to identify and characterise the meteorological patterns associated with similar and different surface concentration levels in this complex region.

Factors affecting the Be surface concentration and its extremely high occurrences over the Scandinavian Peninsula during autumn and winter.

Relationships between the beryllium-7 activity concentrations in surface air and meteorological parameters (temperature, atmospheric pressure, and precipitation), teleconnection indices (Arctic Oscillation, North Atlantic Oscillation, and Scandinavian pattern) and number of sunspots are investigated using two multivariate statistical techniques: hierarchical cluster and factor analysis. The beryllium-7 surface measurements over 1995-2011, at four sampling sites located in the Scandinavian Peninsula, are obtained from the Radioactivity Environmental Monitoring Database. In all sites, the statistical analyses show that the beryllium-7 concentrations are strongly linked to temperature.

Wind dynamics' influence on south Spain airborne olive-pollen during African intrusions.

Given its proximity to northern Africa, southern Spain is regularly affected by high-altitude African intrusions. This determines a well-defined wind dynamics at surface levels. Although this weather event-mainly recorded in spring and summer-coincides with the flowering season of many wind pollinated species, its potential influence on long term airborne pollen transport has been not investigated in detail.

Be behaviour and meteorological conditions associated with Be peak events in Spain.

This work regards a comprehensive analysis of the overall distribution of Be activity concentrations in Spain and the synoptic meteorological conditions associated with the highest Be peaks (>8 mBq/m). The use of four sampling stations (Barcelona, Bilbao, Madrid, and Sevilla) included in REMdb, with different latitudinal location, as well as the relatively long time period used in this study (2001-2010), allowed to improve the understanding of Be spatio-temporal distribution in Spain. The comparison of the Be activity concentrations mean values indicated a north-south gradient (from 3.

Estimating the terrestrial gamma dose rate by decomposition of the ambient dose equivalent rate.

An extensive network of dose rate monitoring stations continuously measures ambient dose rate across Europe, as part of the EURDEP system. Its purpose is early warning in radiological emergencies and documenting its temporal and spatial evolution. In normal conditions, when there is no contribution to the dose rate signal coming from fresh anthropogenic contamination, the data represent the radiation "background", i.

Identification of airborne radioactive spatial patterns in Europe - Feasibility study using Beryllium-7.

The present study proposes a methodology to identify spatial patterns in airborne radioactive particles in Europe. The methodology is based on transforming the activity concentrations in the set of stations for each month (monthly index), due to the tightly spaced sampling intervals (daily to monthly), in combination with hierarchical and non-hierarchical clustering approaches, due to the lack of a priori knowledge of the number of clusters to be created. Three different hierarchical cluster methodologies are explored to set the optimal number of clusters necessary to initialize the non-hierarchical one (k-means).

The role of mesoscale meteorology in modulating the (222)Rn concentrations in Huelva (Spain)--impact of phosphogypsum piles.

The combined analysis of (222)Rn activity concentrations and mesoscale meteorological conditions at Huelva city (Spain) was addressed in this study to understand the potential impact of phosphogypsum piles on the (222)Rn activity concentrations registered at this area. Hourly mean data from April 2012 to February 2013 registered at two sampling sites (Huelva city and in the background station of El Arenosillo, located 27 km to the south-east) have been used in the study. The results of the present study showed a large difference in mean radon concentrations between the two stations during the sampling period, 6.

A climatology of ⁷Be in surface air in European Union.

This study presents a European-wide analysis of the spatial and temporal distribution of the cosmogenic isotope (7)Be in surface air. This is the first time that a long term database of 34 sampling sites that regularly provide data to the Radioactivity Environmental Monitoring (REM) network, managed by the Joint Research Centre (JRC) in Ispra, is used. While temporal coverage varies between stations, some of them have delivered data more or less continuously from 1984 to 2011.

Analysis of the vertical radon structure at the Spanish "El Arenosillo" tower station.

This paper presents an analysis of one year of hourly radon and meteorological measurements at 10 m and 100 m a.g.l.

Cluster analysis of intradiurnal holm oak pollen cycles at peri-urban and rural sampling sites in southwestern Spain.

The impact of regional and local weather and of local topography on intradiurnal variations in airborne pollen levels was assessed by analysing bi-hourly holm oak (Quercus ilex subsp. ballota (Desf.) Samp.

Spatial and temporal variation of surface ozone, NO and NO₂ at urban, suburban, rural and industrial sites in the southwest of the Iberian Peninsula.

Surface ozone is one of the most important photochemical pollutants in the low atmosphere, causing damage to human health, vegetation, materials and climate. The weather (high temperatures and high solar radiation), orography (presence of the Guadalquivir valley) and anthropogenic (the cities of Cádiz, Córdoba, Huelva and Seville and two important industrial complexes) characteristics of the southwestern Iberian Peninsula make this region ideal for the formation and accumulation of ozone. To increase the knowledge of ozone behaviour in this area, the monthly, daily and weekly variations of ozone and its precursors, nitrogen oxides (NO(x) = NO + NO2), were analysed over a 4-year period (2003 to 2006).

Improvement in the accuracy of back trajectories using WRF to identify pollen sources in southern Iberian Peninsula.

Airborne pollen transport at micro-, meso-gamma and meso-beta scales must be studied by atmospheric models, having special relevance in complex terrain. In these cases, the accuracy of these models is mainly determined by the spatial resolution of the underlying meteorological dataset. This work examines how meteorological datasets determine the results obtained from atmospheric transport models used to describe pollen transport in the atmosphere.

Radioactive impact in South Korea from the damaged nuclear reactors in Fukushima: evidence of long and short range transport.

Traces of long-lived fallout-derived radioisotopes ((134)Cs and (137)Cs) were found in wet and dry deposition samples collected from the west and east coasts of South Korea from March to May 2011 following the release of radionuclides from the damaged nuclear power plants in Fukushima, Japan. The analysis of air mass back trajectory and atmospheric pressure systems indicated that the Fukushima-derived radiocaesium had predominantly reached South Korea from the west by surface westerlies from 11 March to 5 April; however, after 6 April, air masses arrived from Japan directly due to a high pressure system that developed to the east of Japan. Spatial variation of deposition fluxes of radiocaesium in South Korea was partly attributed to the presence of local longitudinal orography.