Radioactivity measurements in the atmosphere and water column of Rogoznica Lake (central Adriatic)

2021 ◽  
Author(s):  
Ivana Tucaković ◽  
Sarah Mateša ◽  
Ivana Coha ◽  
Marija Marguš ◽  
Milan Čanković ◽  
...  
Keyword(s):  
Water Column ◽  
Long Range ◽  
Lake Water ◽  
Dry Deposition ◽  
Long Range Transport ◽  
Atmospheric Input ◽  
Air Masses ◽  
Activity Concentrations ◽  
Range Transport ◽  
Radionuclide Activity

<p>Croatian Science Foundation MARRES project (MARine lake (Rogoznica) as a model for EcoSystem functioning in a changing environment) aims to investigate the unique environment (slow exchange of seawater with the sea; atmospheric input is the only source of freshwater) of the marine lake which is an example of highly stratified (permanent anoxia bellow 9 m depth), and by climate changes affected marine system in the middle of the eastern Adriatic coast (43.53° N, 15.95° E). The area of the lake is characterized by the extensive tourism and mariculture, and the low impact of local industrial activities. It is also affected by the combined influence of long-range transport of air masses and local emissions (open-fire events).</p><p>An important part of the project is focused on the exchange and interaction between atmosphere, water column and sediment by measuring the atmospheric input (wet and dry deposition) of sulphur compounds, organic carbon, trace metals and radionuclides (Be-7, Pb-210).</p><p>This work for the first time will present the current state of the measurements of radioactivity in the Rogoznica lake area, including samples of aerosol particulate matter, PM2.5 < 2.5 um, rainwater and lake water column. Namely, the concentrations of Be-7 and Pb-210 in PM2.5 are measured to determine and correlate the dynamics of particle transport, meteorological information, especially origin of air masses and seasonal variation of PM2.5. While presence of Be-7 indicates the recent wet or dry deposition from the upper parts of the atmosphere, Pb-210 may be used as a tracer for continental air masses. Therefore, it can also indicate the influence of the pollution induced by human activity. Regarding that, special attention will be paid to compare results before and during the Covid-19 lockdown periods.</p><p>So far, preliminary results do not show significant difference in PM2.5 masses and measured radionuclide activity concentrations for the lockdown period. Be-7 and Pb-210 were regularly detected in aerosols collected on a glass fiber filters during a one-week sampling periods with the air flow rate of 2.3 m<sup>3</sup>/h. Their activity concentrations are determined by gamma spectrometry using High Purity Germanium detectors. The results are found to be correlated with PM2.5 masses, ranging from 2.9 to 12.2 Bq/m<sup>3</sup> for Be-7 and from 0.5 to 2.5 Bq/m<sup>3</sup> for Pb-210. First analyses show that the highest values can be related to the long-range transport of air masses and to the recorded near open-fire event. As expected, Be-7 is also detected in almost every rainwater sample (event), with the activity concentration up to 5.6 Bq/L, while low activities of Pb-210 are detected only sporadically. Related to that, Be-7 is detected in lake water column as well, but only in the surface layer and in samples collected during, or immediately after the rain events. </p><p>Dynamics and seasonal variation of radionuclide activity concentrations in here studied samples will be discussed, and the relationships with some meteorological parameters (temperature, wind speed, relative humidity, precipitation level) as well as local and long-range transport and physico-chemical conditions in the lake water column will be established.</p>

scholarly journals First simultaneous measurements of peroxyacetyl nitrate (PAN) and ozone at Nam Co in the central Tibetan Plateau: impacts from the PBL evolution and transport processes

2017 ◽  
Author(s):  
Xiaobin Xu ◽  
Hualong Zhang ◽  
Weili Lin ◽  
Ying Wang ◽  
Shihui Jia
Keyword(s):  
Long Range ◽  
Early Morning ◽  
Diurnal Variations ◽  
Long Range Transport ◽  
Nam Co ◽  
Monsoon Period ◽  
Air Masses ◽  
Upper Troposphere ◽  
Central Tibetan Plateau ◽  
Range Transport

Abstract. Both peroxyacetyl nitrate (PAN) and ozone (O3) are key photochemical products in the atmosphere. Most of the previous in-situ observations of both gases have been made in polluted regions and at low altitude sites. Here we present first simultaneous measurements of PAN and O3 at Nam Co (NMC, 90°57′ E, 30°46′ N, 4745 m  a.s.l.), a remote site in the central Tibetan Plateau (TP). The observations were made during summer periods in 2011 and 2012. The PAN concentrations averaged 0.36 ppb (range: 0.11–0.76 ppb) and 0.44 ppb (range: 0.21–0.99 ppb) during 16–25 August 2011 and 15 May to 13 July 2012, respectively. The O3 concentration varied from 27.9 ppb to 96.4 ppb, with an average of 60.0 ppb. Profound diurnal cycles of PAN and O3 were observed, with minimum values around 05:00 LT, steep rises in the early morning, and broader platforms of high values during 09:00–20:00 LT. We find that the evolution of planetary boundary layer (PBL) played a key role in shaping the diurnal patterns of both gases, particularly the rapid increases of PAN and O3 in the early morning. Air entrainment from the free troposphere into the PBL seemed to cause the early morning increase and be a key factor of sustaining the daytime high concentrations of both gases. The days with higher daytime PBL (about 3 km) showed stronger diurnal variations of both gases and were mainly distributed in the drier pre-monsoon period, while those with shallower daytime PBL (about 2 km) showed minor diurnal variations of both gases and were mainly distributed in the humid monsoon period. Episodes of higher PAN levels were observed occasionally at NMC. These PAN episodes were caused either by rapid downward transport of air masses from the middle/upper troposphere or by long-range transport of PAN plumes from North India. The PAN level in the downward transport cases ranged from 0.5 ppb to 0.7 ppb and may indicate the PAN abundance in the middle/upper troposphere. In the long-range transport case, the PAN level varied in the range of 0.6–1.0 ppb. This long-range transport process influenced most of the western and central TP region for about a week in early June 2012. Our results suggest that polluted air masses from South Asia can significantly enhance the PAN level over the TP. As PAN act as a reservoir of NOx, the impacts of pollution transport from South Asia on tropospheric photochemistry over the TP region deserve further studies.

Metal contamination of natural surface soils from long-range atmospheric transport: Existing and missing knowledge

2006 ◽  
Vol 14 (3) ◽  
pp. 169-186 ◽  
Author(s):  
Eiliv Steinnes ◽  
Andrew J Friedland
Keyword(s):  
Organic Matter ◽  
Long Range ◽  
Atmospheric Transport ◽  
Long Range Transport ◽  
Surface Soils ◽  
Air Masses ◽  
Range Transport ◽  
Zinc Cadmium ◽  
Lead Zinc ◽  
Temporal And Spatial

This review focuses on the long-range atmospheric transport of metals to organic-rich surface soils (mostly 50–90% organic matter) in the temperate, coniferous, and boreal zones of North America and Europe. From various air-pollution related measurements (air, precipitation, moss, peat cores) Pb and Zn are known to be transported long distances in the air in large amounts. Arsenic, Cd, Hg, Sb, and Se are also typical representatives of long-range transported air masses, and there is evidence that Ag, Bi, In, Mo, Tl, and W belong to this group of elements. Through the use of “environmental archives” such as ice and peat cores it has become evident that long-range transport of pollutants and associated contamination of natural surfaces is not just a recent phenomenon. There is compelling evidence for widespread enrichment of surface soil horizons in Pb from long-range transport, and many studies support enrichment of Zn. Mercury is also generally elevated by anthropogenic emissions over natural levels in organic-rich surface soils, whereas results for Cd are less conclusive. There is evidence that As, Se, Ag, Mo, In, Sb, W, Tl, and Bi all are subject to some enrichment in organic-rich surface soils from long-range atmospheric transport, but studies are still few for most of these elements. With the exception of Pb, little is known about residence times of the elements in the organic-rich surface horizon, and more research is needed on this topic. Further studies are desirable on the temporal and spatial trends in supply of the above elements, which are poorly known in large parts of the northern temperate zone.Key words: natural soils, metals, long-range atmospheric transport, organic matter, lead, zinc, cadmium, mercury.

scholarly journals Ozone and carbon monoxide over India during the summer monsoon: regional emissions and transport

2016 ◽  
Vol 16 (5) ◽  
pp. 3013-3032 ◽  
Author(s):  
Narendra Ojha ◽  
Andrea Pozzer ◽  
Armin Rauthe-Schöch ◽  
Angela K. Baker ◽  
Jongmin Yoon ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Long Range ◽  
Summer Monsoon ◽  
Lower Troposphere ◽  
Southern India ◽  
Long Range Transport ◽  
Minor Role ◽  
Air Masses ◽  
Range Transport ◽  
Regional Emissions

Abstract. We compare in situ measurements of ozone (O3) and carbon monoxide (CO) profiles from the CARIBIC program with the results from the regional chemistry transport model (WRF-Chem) to investigate the role of local and regional emissions and long-range transport over southern India during the summer monsoon of 2008. WRF-Chem successfully reproduces the general features of O3 and CO distributions over the South Asian region. However, absolute CO concentrations in the lower troposphere are typically underestimated. Here we investigate the influence of local relative to remote emissions through sensitivity simulations. The influence of 50 % increased CO emissions over South Asia leads to a significant enhancement (upto 20 % in July) in upper tropospheric CO in the northern and central Indian regions. Over Chennai in southern India, this causes a 33 % increase in surface CO during June. However, the influence of enhanced local and regional emissions is found to be smaller (5 %) in the free troposphere over Chennai, except during September. Local to regional emissions are therefore suggested to play a minor role in the underestimation of CO by WRF-Chem during June–August. In the lower troposphere, a high pollution (O3: 146.4 ± 12.8, CO: 136.4 ± 12.2 nmol mol−1) event (15 July 2008), not reproduced by the model, is shown to be due to transport of photochemically processed air masses from the boundary layer in southern India. A sensitivity simulation combined with backward trajectories indicates that long-range transport of CO to southern India is significantly underestimated, particularly in air masses from the west, i.e., from Central Africa. This study highlights the need for more aircraft-based measurements over India and adjacent regions and the improvement of global emission inventories.

scholarly journals Concentration Trajectory Route of Air pollution with an Integrated Lagrangian model (C-TRAIL model v1.0) derived from the Community Multiscale Air Quality Modeling (CMAQ model v5.2)

2020 ◽  
Author(s):  
Arman Pouyaei ◽  
Yunsoo Choi ◽  
Jia Jung ◽  
Bavand Sadeghi ◽  
Chul Han Song
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Long Range ◽  
Lagrangian Model ◽  
Long Range Transport ◽  
Air Masses ◽  
Range Transport ◽  
Potential Sources ◽  
Model C ◽  
Co Concentrations

Abstract. This paper introduces a reliable and comprehensive Lagrangian output (Concentration Trajectory Route of Air pollution with Integrated Lagrangian model, C-TRAIL version 1.0) from an Eulerian air quality model for validating the source-receptor link by following real polluted air masses. To investigate the concentrations and trajectories of air masses simultaneously, we implement the trajectory-grid (TG) Lagrangian advection scheme in the CMAQ (Community Multiscale Air Quality) Eulerian model version 5.2. The TG algorithm follows the concentrations of representative air packets of species along trajectories determined by the wind field. The generated output from C-TRAIL accurately identifies the origins of pollutants. For validation, we analyzed the results of C-TRAIL during the KORUS-AQ campaign over South Korea. Initially, we implemented C-TRAIL in a simulation of CO concentrations with an emphasis on the long- and short-range transport effect. The output from C-TRAIL reveals that local trajectories were responsible for CO concentrations over Seoul during the stagnant period (May 17–22, 2016) and during the extreme pollution period (May 25–28, 2016), highly polluted air masses from China were distinguished as sources of CO transported to the Seoul Metropolitan Area (SMA). We conclude that long-range transport played a crucial role in high CO concentrations over the receptor area during this period. Furthermore, for May 2016, we find that the potential sources of CO over that SMA were the result of either local transport or long-range transport from the Shandong Peninsula and, in some cases, from north of the SMA. By identifying the trajectories of CO concentrations, one can use the results from C-TRAIL to directly link strong potential sources of pollutants to a receptor in specific regions during various time frames.

scholarly journals Measurement report: Long-range transport patterns into the tropical northwest Pacific during the CAMP<sup>2</sup>Ex aircraft campaign: chemical composition, size distributions, and the impact of convection

2021 ◽  
Vol 21 (5) ◽  
pp. 3777-3802
Author(s):  
Miguel Ricardo A. Hilario ◽  
Ewan Crosbie ◽  
Michael Shook ◽  
Jeffrey S. Reid ◽  
Maria Obiminda L. Cambaliza ◽  
...  
Keyword(s):  
Long Range ◽  
Southwest Monsoon ◽  
Long Range Transport ◽  
Northwest Pacific ◽  
Back Trajectories ◽  
Air Masses ◽  
China Sea ◽  
Range Transport ◽  
Transport Patterns ◽  
The Impact

Abstract. The tropical Northwest Pacific (TNWP) is a receptor for pollution sources throughout Asia and is highly susceptible to climate change, making it imperative to understand long-range transport in this complex aerosol-meteorological environment. Measurements from the NASA Cloud, Aerosol, and Monsoon Processes Philippines Experiment (CAMP2Ex; 24 August to 5 October 2019) and back trajectories from the National Oceanic and Atmospheric Administration Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) were used to examine transport into the TNWP from the Maritime Continent (MC), peninsular Southeast Asia (PSEA), East Asia (EA), and the West Pacific (WP). A mid-campaign monsoon shift on 20 September 2019 led to distinct transport patterns between the southwest monsoon (SWM; before 20 September) and monsoon transition (MT; after 20 September). During the SWM, long-range transport was a function of southwesterly winds and cyclones over the South China Sea. Low- (high-) altitude air generally came from MC (PSEA), implying distinct aerosol processing related to convection and perhaps wind shear. The MT saw transport from EA and WP, driven by Pacific northeasterly winds, continental anticyclones, and cyclones over the East China Sea. Composition of transported air differed by emission source and accumulated precipitation along trajectories (APT). MC air was characterized by biomass burning tracers while major components of EA air pointed to Asian outflow and secondary formation. Convective scavenging of PSEA air was evidenced by considerable vertical differences between aerosol species but not trace gases, as well as notably higher APT and smaller particles than other regions. Finally, we observed a possible wet scavenging mechanism acting on MC air aloft that was not strictly linked to precipitation. These results are important for understanding the transport and processing of air masses with further implications for modeling aerosol lifecycles and guiding international policymaking to public health and climate, particularly during the SWM and MT.

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