Dust Resuspension Rates in Kuwait: Insights from 7Be and 137Cs Radionuclides

doi:10.21203/rs.3.rs-3965298/v1

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Dust Resuspension Rates in Kuwait: Insights from 7Be and 137Cs Radionuclides

https://doi.org/10.21203/rs.3.rs-3965298/v1

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published 10 Oct, 2024

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Dust resuspension rates in four different landscapes in Kuwait were estimated over a two-year period using 7Be and 137Cs radionuclides. The average rates of resuspension of particles labeled with 7Be (2 × 10-3 ± 3.9 x 10-4 s-1) were much higher than those of particles labeled with 137Cs (1.6 x 10-6 ± 2.15 x 10-7 s-1), which indicates increased short-term fluctuations in recently deposited dust. Conversely, the resuspension rates for particles labeled with 137Cs were considerably lower, which better reflects long-term variations in dust resuspension. This evaluation approach may provide a foundation for future studies assessing the impact of suspended dust particulates on the performance of solar power systems, in conjunction with other influencing factors like vertical mass flux.

137Cs

7Be

resuspension factor

particle-settling velocity

arid region

Dust storms in the Middle East significantly diminish air quality (Doronzo et al. 2016; Al-Dousari et al. 2020). The increasing frequency and intensity of such storms, particularly in the Arabian Gulf region, could indicate the effects of climate change (Neelamani and Al-Dousari 2016; Taghavi et al. 2017). The Middle East, North Africa, and Asia have emerged as the primary contributors to global dust storms (Al-Dousari et al. 2018, 2019, 2020, 2022).

Studies of dust fallout in Kuwait have demonstrated high deposition rates and significant concentrations of trace metals and air pollutants (Al-Awadhi and AlShuaibi 2013; Al-Dousari et al. 2016). The dust storms studied in Kuwait are a public health concern because they can contain organic and inorganic pollutants, some of which are toxic even at low concentrations, such as lead and cadmium (Doronzo and Al-Dousari 2019; Al-Dousari et al. 2020).

Radiological analyses of dust can reveal the characteristics of dust fallout and related hazards while facilitating the study of various atmospheric processes. Radionuclides, including ⁷Be, ²¹⁰Pb, ¹³⁷Cs, and other radioisotopes within the uranium and thorium series, are invaluable in environmental research due to their distinct properties, which enable the tracing and backtracking of events across short-, medium-, and long-term scales (Keller et al. 2017; Mezina et al. 2020; Baccolo et al. 2023). These radioisotopes are particularly useful in atmospheric studies, as most radionuclides are quickly adsorbed into fine atmospheric aerosols, dispersing both horizontally and vertically in response to climatic conditions (Aba et al. 2020). This process is crucial for assessing radiation exposure during both the early and late phases of nuclear accidents, when the risk is significantly influenced by the inhalation of fine suspended particles carrying radionuclides.

Naturally occurring ⁷Be of cosmogonic origin and anthropogenic ¹³⁷Cs radionuclides serve as predominant tracers for studying the scavenging behavior and vertical transport of fine atmospheric particles (Aba et al. 2020; Whicker et al. 2021). Specifically, ⁷Be is a cosmogonic radionuclide produced predominantly in the lower stratosphere and to a lesser extent in the upper troposphere (Golubenko et al. 2022; Zheng et al. 2023). It decays into ⁷Li through electron capture, with a half-life of 53 days, emitting gamma energy at 478 keV, which can easily be detected and quantified using gamma spectrometry. The mean tropospheric residence time of ⁷Be in Kuwait is estimated to be 4.5 days (Aba et al. 2020). On the other hand, ¹³⁷Cs originating from human activities decays into ¹³⁷Ba through beta decay, with a half-life of 30.2 years. ¹³⁷Cs emits 661.6 KeV gamma energy, which can easily be resolved using gamma spectrometry. The primary sources of ¹³⁷Cs in the atmosphere derive from nuclear weapon testing in the 1950s and 1960s as well as the nuclear accidents at Chernobyl and Fukushima in 1986 and 2011, respectively (Aba et al. 2014).

This study aimed to assess the effectiveness and feasibility of using 137Cs and 7Be radiotracer techniques to estimate dust resuspension rates by measuring the settling velocity and resuspension factors of fallen dust. This process is crucial for advancing our comprehension of dust phenomena and designing efficient approaches to mitigate dust deposition and resuspension impacts. These values will be valuable indicators for selecting future photovoltaic installation sites in the country. They align with Kuwait’s National Development Plan 2035 (New Kuwait), which aims to source 15% of the nation’s energy from renewables, including photovoltaic solar power, at potential solar energy locations (Alsayegh 2021). While this study focuses on resuspension factors, an upcoming study will examine vertical mass flux and its impact on solar panel efficiency in Kuwaiti areas suitable for solar and photovoltaic installations. This will help estimate the efficiency loss in solar panels that results from dust accumulation. By establishing parameters for resuspension, deposition velocity, and vertical mass flux, we can gain a clearer picture of how airborne dust affects solar panel performance. Monitoring dust resuspension rates allows us to predict dust build-up on panels and its impact on energy production. This information is critical for achieving both economic and developmental goals. Therefore, estimating dust resuspension rates at potential solar panel sites is essential for carrying out strategic development plans in Kuwait (Sulaiman et al. 2011; Al-Dousari 2021; Quan et al. 2022).

2.1. Study Sites

Kuwait, which covers an area of 17,818 square kilometers, is situated along the northern shore of the Arabian Gulf. It shares maritime boundaries with Iran and borders with Saudi Arabia to the south and Iraq to the north. Characterized by long, hot summers and short, mild winters, Kuwait’s climate typifies a desert environment. Dust storms are particularly frequent during the spring (February–April) and summer (May–August) (Al-Hemoud et al. 2017). Higher relative humidity and temperatures reaching up to 50°C in the shade mark the summer season. The country’s sandy soil has low levels of organic matter and moisture. Due to the scarcity of natural water supplies, agricultural practices in the region predominantly rely on brackish groundwater and desalinated seawater. For this study, four locations representing relatively diverse landscapes in Kuwait were selected (Fig. 1) and designated as S1, S2, S3, and S4.

S1: Kuwait City, the state capital, is located on the southern bank of Kuwait Bay and hosts 534,000 residents living in an area of 169 square kilometers.

S2: Al-Wafra, an agricultural region in Southern Kuwait, is primarily dedicated to vegetable production. It encompasses approximately 200 square kilometers of privately owned farms that significantly contribute to the local food supply.

S3: Al-Salmy, an open area characterized by mobile sand dunes, epitomizes the arid desert landscape of Kuwait.

S4: Bubiyan Island, a protected region spanning 863 square kilometers in the northeastern Arabian Gulf, is distinguished by its unique salt flats and is ecologically classified as a sabkha.

Further details regarding the specific characteristics of each landscape, including their climatic conditions, soil type, and predominant vegetation, are provided in Table 1.

Table 1

Locations of dust sample collection and their specifications.
Site No.	Coordinates (Long., Lat.)	Local name	Landscape	Land use
S1	47.902733, 29.349166	Kuwait City	Urban	Urban area
S3	47.267222, 29.154277	Al-Salmy	Mobile sand	Open desert area
S4	48.336446, 29.746924	Bubiyan Island	Sabkha	Preserved area
S2	47.998233, 28.610233	Al-Wafra	Agriculture	Farms

2.2. Dust Fallout Sampling

Four dust traps, which were made from polyvinyl chloride buckets with dimensions of 0.2 meters in diameter and 0.4 meters in depth elevated 2.4 meters above ground level, were deployed across diverse environments, including urban, rural, and open-preserved areas, to collect a wide range of dust fallout samples. These traps were engineered to collect representative dust samples while minimizing contamination and dispersion from wind or bird interference; they used glass marbles and an inverted metal basket strap (Fig. 2). Following sample collection for 30 days, the accumulated dust was carefully rinsed with 0.2 M of HCl (Hydrochloric acid) and acidified distilled water in a 1-liter beaker and subsequently dried, forming a composite sample for each location.

The combined weight of the dust collected by the four bucket traps “cross sectional area of 0.126 m²” at each site varied from 0.5 g to 15 g, providing a sufficient quantity for accurate radioactivity analysis. To achieve statistically reliable peak area calculations with an uncertainty of less than 10%, the prepared samples were subject to an extended period of measurement with a low-background gamma spectrometry system. ⁷Be and ¹³⁷Cs activity was quantified using semi-empirical efficiency calibration with a traceable gamma mixed standard (QCYB-41 & QCYB-40, KDD, Germany) and LabSOCS software (Canberra Inc.). This approach was imperative to accommodate the notable variations in the quantities of dust collected. The decay of ⁷Be was evaluated during the sampling period prior to the determination of monthly deposition fluxes (Bq m^− 2) based on the rates of monthly dust deposition (g m^− 2). The decay of ⁷Be was evaluated during the sampling period prior to the determination of monthly deposition fluxes (Bq m^− 2) based on the rates of monthly dust deposition (g m^− 2).

2.3. Airborne Radionuclide Activity Concentration

Ground-level air activity concentrations were measured concurrently using an automated Radionuclide Aerosol Sampler and Analyzer (RASA), a component of the International Monitoring System situated at Station RN40 in Kuwait (Fig. 1). The RASA is equipped with a rod-type filter that has demonstrated 85% efficiency in capturing air particles. The filter collected air particles for 24 hours at a rate of 610 m³ h^− 1, resulting in a total sample volume of approximately 14,600 m³. To mitigate the influence of short-lived radon progeny, a 24-hour delay was instituted prior to analysis using a high-purity germanium detector. The activity concentrations of ⁷Be and ¹³⁷Cs, quantified in µBq m^− 3, are reported alongside associated uncertainties determined at a 95% confidence level.

2.4. ⁷Be and ¹³⁷Cs Total Ground Deposition Calculation

Accurate measurements of areal activity density (inventory) are essential for estimating resuspension rates. This term describes surface contamination density (Bq m^− 2) and includes the distribution of radionuclides in the soil. The relatively short half-life of the ⁷Be radionuclide makes it challenging to precisely estimate its total inventory. To address this, we assumed that the daily deposition fluxes of ⁷Be remained constant throughout the 30-day sampling period. Consequently, the mass balance model was used to determine the areal activity density of the ⁷Be (At) as follows:

$$\:{A}_{t}=A.{\int\:}_{0}^{t}{e}^{-\lambda\:t}dt$$

where A represents the daily deposition (Bq m^− 2), λ is the decay constant for ⁷Be (0.013 d^− 1), and t denotes the sampling period. Consequently, the daily deposition flux was determined as presented in Eq. (2) (Shi et al. 2011):

$$\:A=\:\frac{\lambda\:.{A}_{t}}{1-{e}^{-\lambda\:t}}\:$$

The ⁷Be inventory at the end of each sampling period underwent decay correction and was subsequently added to the previous inventory. The long-term presence of ⁷Be in the soil was calculated by determining the daily deposition of ⁷Be (Bq m^− 2 d^− 1) for each month-long sampling period and then tracking the ongoing inventory of ⁷Be in the soil. This process involved adjusting the previous month’s ⁷Be amount for radioactive decay and adding the adjusted value to the new measurement (activity) for the current month. This method created a continuous record of the ⁷Be inventory, reflecting both fresh deposition and natural decay. The median ⁷Be inventory across Kuwait was calculated as 198 ± 26 Bq m^− 2.

In contrast, the longer half-life of ¹³⁷Cs allows sufficient time for it to bind to fine soil particles, such as mud and clay, during precipitation events and migrate deeper into the soil. The depth of radionuclide migration is dependent on the physicochemical properties of the radionuclides and soil characteristics. Our previous work (Aba et al. 2021) showed that more than 90% of the ¹³⁷Cs was concentrated in the top 10 cm, with 90% of the ¹³⁴Cs situated at a depth of 5.37 cm.

To calculate the inventory of ¹³⁷Cs, topsoil samples measuring 10 cm x 10 cm x 10 cm were collected from designated locations at each site. These samples were sieved through a 2-mm mesh and then weighed, placed in calibrated containers, and analyzed using gamma spectrometry. The inventory of ¹³⁷Cs was calculated in units of Bq m^− 2, taking into account the specific activity (Bq kg^− 1), soil density (kg m^− 3), and sample depth (m^− 1). The inventories calculated for the four landscapes were as follows: 358 ± 66 Bq m^− 2 for the urban area, 311 ± 67 Bq m^− 2 for the mobile sand, 635 ± 48 Bq m^− 2 for the sabkha, and 212 ± 138 Bq m^− 2 for the agricultural regions.

2.5. Calculation of Dust Particle Resuspension Rate

The atmosphere is cleansed by the removal of suspended particulate matter, primarily through dry and wet processes. In desert environments, such as that of Kuwait, deposition mostly occurs via dry processes, except during periods of minimal rainfall in the spring (Aba et al. 2016). The radiotracer method for estimating dust resuspension rates considers various factors, including the size of fine particles, the origin of radionuclide-labeled particles, climatological conditions, and site specificity.

The formula commonly used to calculate resuspension rates is based on the fraction of surface species removed within a specific unit of time (Slinn 1978). Numerous prediction models have been developed and validated (Garger et al. 1999; Kim et al. 2014). However, our estimation used empirical data on the radioactive airborne concentration and flux of the resuspended particles to more accurately represent the actual situation. The resuspension rate (Λ), measured in units of s^− 1, was calculated using Eq. (3), the general equation described by Galeriu and Kryshev (Garger et al. 1999):

Λ = K V_d (3)

In this context, K represents the resuspension factor (m^− 1) under the assumption that airborne material originates entirely from the surface (Ferro 2022). The calculation of K involves determining the ratio of the atmospheric radionuclide concentration C_s (Bq m^− 3) to its actual ground deposit D (Bq m^− 2), as in Eq. (4)

K = C_s/D (4)

V_d denotes the deposition velocity or settling particle velocity (cm s^− 1), calculated as the ratio of the total deposition flux (F) of the radionuclide (Bq cm^− 2 s^− 1) to the atmospheric radionuclide concentration (C_s) (Bq cm^− 3), as in Eq. (5):

V_d = F/C_s (5)

The deposition flux of the radionuclides (F) was calculated as the ratio of the total deposition (D), given in units of activity per area (Bq m⁻²), to the duration of the deposition period, as shown in Eq. (6):

F (Bq m^− 2 s^− 1) = D (Bq m^− 2)/T (s) (6)

2.6. Quality Assurance

The performance of the ultra-low background gamma spectrometry used for dust analysis was validated via laboratory quality control procedures. Certified reference material possessing known activity levels was employed to monitor the detector’s efficiency and peak shape. Additionally, variations in background radiation and changes in environmental conditions within the laboratory were meticulously monitored and controlled. To further assess the laboratory’s performance, external evaluations were regularly undertaken through participation in exercises organized by the International Atomic Energy Agency’s Analytical Laboratories for the Measurement of Environmental Radioactivity Network.

3.1. Average Monthly Depositional Rates and Atmospheric Concentrations of ⁷Be and ¹³⁷Cs

The concentrations of ⁷Be and ¹³⁷Cs, mass of the deposited dust, and surface area of the collectors were employed to determine the monthly depositional fluxes. Furthermore, the atmospheric radionuclide concentration (expressed in µBq m^− 3) was evaluated by examining the radionuclide content present on the air filter, as well as the volume of air that had been sampled. The monthly atmospheric concentrations of ⁷Be and ¹³⁷Cs were derived by computing the average daily concentrations. Subsequently, the mean deposition rates and atmospheric concentrations for the corresponding months throughout the two-year monitoring period were calculated. Although this approximation may introduce a broader range of estimates, it accommodates maximal variations in the factors that affect dust resuspension rates and deposition velocities. These factors include the incidence of dust storms and fluctuations in climatic conditions.

Figure 3 presents two panels. Panel A illustrates monthly variations in the deposition of ⁷Be and ¹³⁷Cs alongside precipitation rates (the total monthly rainfall during the two-year study period; Aba et al. 2018). Significant agreement was observed between the trends of depositional flux for ⁷Be and ¹³⁷Cs and the precipitation rates (Fig. 3(A)). The correlation coefficient for the depositional fluxes of ⁷Be and ¹³⁷Cs exhibited a very strong positive relationship (r = 0.79, p < 0.05). Furthermore, very strong correlations were identified between the depositional fluxes of ⁷Be and ¹³⁷Cs and the precipitation rates (r = 0.81, p < 0.05 and r = 0.84, p < 0.05, respectively). This indicates a similar mechanism governing the removal of suspended particles from the atmosphere.

Contrarily, a positive but insignificant correlation (r = 0.25, p = 0.43) was recognized between the atmospheric concentrations of ⁷Be and ¹³⁷Cs, as highlighted in Fig. 3(B). The divergence in the distribution patterns of the two radionuclides can be attributed to their different sources and the unique characteristics of their movement and transport within the ecosystem, which are subject to influences from both local and long-range transport mechanisms. In this sequence, the residence time of the particles, the half-lives of the radionuclides, local movement, and long-range transport significantly influence the concentrations of radionuclides in ground-level air. Furthermore, a weak negative correlation (-0.24) was observed between the atmospheric concentration of ⁷Be and precipitation rates, as shown in Fig. 3(B). This result aligns with findings from diverse geographical regions. For example, elevated air concentrations of ⁷Be were detected in air filters at the CTBTO RN42 station in Malaysia during a period of low precipitation (Rashid and Zolkaffly 2021). Nevertheless, the correlation was insufficiently robust to the significance of the atmospheric ⁷Be washout process.

In contrast to the behavior of ⁷Be, a moderate correlation (r = 0.49, p = 0.11) was noted between the atmospheric concentration of ¹³⁷Cs and the precipitation rates. The differential behavior is likely attributable to the distinct physical properties of the radioactive isotopes, especially their half-lives, which notably influence the potential for particle size growth. This finding is supported by our prior research (Ismaeel et al. 2020), in which the activity median aerodynamic diameter of ⁷Be was determined to be 0.463 µm. Additionally, a larger activity median aerodynamic diameter of ¹³⁷Cs resuspension dust in Kuwait was calculated to be 1.43 µm, consistent with the range reported in Japan (1.5–1.6 µm) (Miyamoto et al. 2014). Moreover, studies conducted in Oak Ridge, Tennessee have shown that the particle size of ¹³⁷Cs significantly increases over time, unlike that of ⁷Be, which does not exhibit such growth (Papastefanou 2008). Further discussion and elaboration are provided in the subsequent section.

3.2. Dust Particle Resuspension Rate

The movement and transportation of dust particles are influenced by their size (mass) and settling velocity. Eq. (3) was used to calculate the rates at which particles labeled with ⁷Be and ¹³⁷Cs are resuspended. This equation establishes a relationship between the rate of resuspension and the velocity at which the particles settle, as presented in Fig. 4.

It is evident that the settling velocity significantly influences the rate of particle resuspension. As indicated in Fig. 4, the average resuspension factors for particles labeled with ⁷Be and ¹³⁷Cs were found to be 3.76 x 10^− 3 and 1.95 x 10^− 6 m^− 1 respectively. A notably lower resuspension factor (1.4 x 10^− 10 m^− 1) was documented for particles labeled with ¹³⁷Cs from Chernobyl in Germany (Rosner and Winkler 2001). The same investigation revealed an even lower resuspension factor for the extremely long half-life of ^239+240Pu (1.0 x 10^− 11 m^− 1). Additionally, Papastefanou et al. (1995) reported that, in Greece, the resuspension factor varied from 1 x 10^− 5 to 1.2 x 10^− 4 m^− 1 for particles labeled with ¹³⁷Cs and from 1.6 x 10^− 4 to 4.2 x 10^− 4 m^− 1 for those labeled with ⁷Be. Conversely, Garland and Cambray (1988) observed a resuspension factor of 1.0 x 10^− 4 m^− 1 in the United Kingdom.

The settling velocity of particles labeled with ¹³⁷Cs (2.2 ± 0.31 cm s^− 1) is approximately 15 times greater than that of particles labeled with ⁷Be (0.15 ± 0.05 cm s^− 1). Previously, elevated settling velocities were documented in Greece by Papastefanou et al. (1995), where the settling velocity for ¹³⁷Cs ranged from 1.3 to 6.3 cm s^− 1, while for ⁷Be, it varied from 0.3 to 0.8 cm s^− 1. Consequently, particles labeled with ¹³⁷Cs are removed from the atmosphere more efficiently than the finer particles labeled with ⁷Be. Kajino et al. (2022) validated this observation during a study of resuspension dust in Japan. The primary reason for this difference is likely linked to the physical properties of the radioactive isotopes, which in turn influence particle growth over time. While ⁷Be possesses a significantly shorter half-life of 53 days, ¹³⁷Cs has a half-life of 30 years, providing particles labeled with ¹³⁷Cs more opportunities to grow as they collide with smaller particles during wind-blown dust events. Although particles labeled with ⁷Be also undergo these collisions, their shorter half-life restricts their growth potential. As a result, particles labeled with ⁷Be tend to be smaller and lighter compared to those labeled with ¹³⁷Cs, leading to a slower descent due to gravitational forces.

The differences in the sizes and settling velocities of particles labeled with ⁷Be and ¹³⁷Cs explain the dynamics of dust particle movement and transportation over both short and long distances. Particles labeled with ¹³⁷Cs are capable of traveling longer distances and increasing in size, whereas particles labeled with ⁷Be are likelier to be deposited locally and have a lower chance of forming larger particles through collisions. Based on our prior observations and our hypothesis regarding potential sources of ¹³⁷Cs, fallout from bomb tests and the Chernobyl accident likely traveled via prevailing north-westerly winds from Turkey, Syria, and the Iraqi desert before being deposited over Kuwait and the Arabian Gulf (Aba et al. 2016, 2018). The contrasting half-lives of ⁷Be (53 days) and ¹³⁷Cs (30 years) are critical when interpreting dust movement and resuspension rates. Due to its short half-life, ⁷Be primarily labels recently deposited dust particles, making it valuable for tracing short-term resuspension events. However, looking only at ⁷Be may lead to underestimations of the total resuspension rate, as natural samples likely contain a mix of particles labeled with radionuclides of varying half-lives. Older dust particles with longer-lived isotopes might also be resuspended, but they would not be detectable by ⁷Be due to its decay. Therefore, the resuspension rate derived solely from ⁷Be could be considered an apparent rate to signal the potential underestimation of the total resuspension.

The impact of land use on the resuspension rates of particles labeled with ¹³⁷Cs and ⁷Be was clearly evident, as illustrated in Fig. (5). Notably, while land use had a negligible effect on the resuspension rates of particles labeled with ⁷Be, a noticeable effect was observed on those labeled with ¹³⁷Cs. The resuspension rates for particles labeled with ¹³⁷Cs varied across land used for different purposes, including urban, preserved, and agricultural areas, with rates ranging from 6.6 × 10^− 9 s^− 1 to 6.2 x 10^− 8 s^− 1 (Fig. 5). However, in the open desert at the Al-Salmy location, the resuspension rates fluctuated between 2.6 x 10^− 8 s^− 1 and a peak value of 2.35 × 10^− 7 s^− 1. It is noteworthy that the resuspension rates for particles labeled with ¹³⁷Cs are considerably lower than those labeled with ⁷Be. Interestingly, dust particles carrying ¹³⁷Cs were resuspended at a much lower rate than those with ⁷Be. This difference is mainly attributable to their size. While both of these radioactive elements are chemically reactive and attach to fine particles, ⁷Be decays much faster than ¹³⁷Cs due to their different half-lives. This means that ¹³⁷Cs has more time to accumulate on larger particles. As a result, ⁷Be-labeled particles are lighter and more easily resuspended by wind. Therefore, the significant difference in half-lives is the key factor in explaining the variation in resuspension rates observed between ⁷Be and ¹³⁷Cs.

Consequently, particles labeled with ⁷Be are likelier to be freshly deposited on the surface of the topsoil, making them susceptible to resuspension soon after deposition. In contrast, particles labeled with ¹³⁷Cs have a longer lifespan within the ecosystem and exhibit lower resuspension rates due to their migration into the deeper soil layers. This phenomenon was noticed on Bubiyan Island, where particles labeled with ¹³⁷Cs were trapped in the muddy-silt surface soil, leading to minimal variation in resuspension rates, which ranged from 7.43 x 10^− 9 to 1.86 x 10^− 8 s^− 1.

However, resuspension rates exhibit considerable variability depending on land uses and climatic factors, particularly in terms of the nature of the radionuclide-labeled particles. For instance, within the hyper-arid climate of Kuwait, the average resuspension rate for particles labeled with ¹³⁷Cs was determined in this study to be 1.6 x 10^− 6 ± 2.16 x 10^− 7 s^− 1. Conversely, in a subtropical climate in Japan (Kajino et al. 2022), the rate was measured as 3.0 x 10^− 10 s^− 1, and within a temperate, rainy climate in Germany (from 1997–1998), the rate (1.6 x 10^− 6 s^− 1) was consistent with that in Kuwait (Rosner and Winkler 2001). Notably, the recorded resuspension rate of particles labeled with ^239+240Pu in Germany was significantly lower (1.17 x 10^− 12 s^− 1) than the rates reported in Nevada, USA, which ranged from 2.7 x 10^− 12 to 4.8 x 10^− 10 s^− 1 in arid/semi-arid climates (Anspaugh et al. 1975).

Our findings highlight the interaction between radionuclide properties and climate in influencing dust resuspension. While radionuclide half-life affect particle size and settling (as discussed previously), climate plays a critical role, particularly in arid regions, such as Kuwait. Here, high wind speeds are a key driver of dust resuspension, significantly impacting resuspension rates. The aridity itself, characterized by low precipitation and scarce vegetation, further enhances the resuspension, even at lower wind speeds. The disruption of compacted soil by human activities, especially off-road vehicle driving, further intensifies this effect, as demonstrated in our previous study at the open desert site in Al-Salmy (Aba et al. 2018). In conclusion, climate classification, the specific characteristics of aged radionuclide-labeled particles, and prevailing climatic conditions collectively exert a significant influence on dust particle resuspension.

Our analysis suggests that both radionuclides might be employed to assess potential sites for future solar power projects. Nevertheless, different solar power technologies exhibit varying sensitivities to dust-related factors. As highlighted by AL-Rasheedi et al. (2020), dust deposition markedly reduces the performance ratio of photovoltaic (PV) systems. Conversely, concentrated solar power (CSP) systems are more vulnerable to dust resuspension, which significantly impacts direct normal irradiance (Abdulrahman et al. 2024). Consequently, the resuspension rate, as measured by ⁷Be, is a more suitable indicator for CSP efficiency. Moreover, our study underscores the influence of landscape characteristics on ¹³⁷Cs-based dust resuspension rate estimation. This method could potentially provide valuable insights for evaluating PV sites as well.

In this research, we explored the applicability of ⁷Be and ¹³⁷Cs radionuclides as tracers for determining deposition velocities and overall resuspension rates in a desert environment. Monthly deposition rates and surface air concentrations were recorded in diverse geographical areas with different land uses. It was observed that the behavior of particles labeled with ⁷Be differs significantly from that of particles labeled with ¹³⁷Cs, facilitating the identification of freshly deposited dust. Over time, particles labeled with ¹³⁷Cs, due to their age, prove effective in tracking long-term variations in dust resuspension. The accuracy of these estimated velocities and rates is critically dependent on the accurate determination of the total ground deposits of the radionuclides. Our study demonstrates the potential of fallout radionuclides as an applicable tool for measuring dust resuspension across Kuwait. This approach may be considered as a foundation for future research investigating the impact of dust on solar power system performance, which ultimately contributes to Kuwait’s sustainable development. The study underscores the importance of engaging with stakeholders to undertake comprehensive environmental protection research aimed at predicting dust behavior following large-scale contamination events.

Competing Interests:

The authors declare that they have no competing interests

Ethics approval:

Not Applicable

Consent to Participate:

Not Applicable

Consent to Publish:

Not Applicable.

Funding:

Kuwait Foundation for the Advancement of Science (KFAS) funded the research project EC063C, under grant number 2008-1401-01.

Authors contributions:

Abdulaziz Aba: conceived and designed the study, formal analysis and writing original draft.

Acknowledgment

The authors would like to express their gratitude to the CTBTO for their generous support and cooperation. Further acknowledgment is extended to the Kuwait Foundation for the Advancement of Science (KFAS) for funding the research project EC063C, under grant number 2008-1401-01, and for permitting the publication of this manuscript.

Data availability statement:

The authors declare that data supporting the finding of this study are available within the paper. If raw data files in another format are required, they are available from the corresponding author upon reasonable request

Aba A, Al-Boloushi O, Ismaeel A, Al-Tamimi S (2021) Migration behavior of radiostrontium and radiocesium in arid-region soil. Chemosphere 281:130953
Aba A, Al-Dousari A, Ismaeel A (2016) Depositional characteristics of 7 Be and 210 Pb in Kuwaiti dust. Journal of Radioanalytical and Nuclear Chemistry 307:15–23
Aba A, Ismaeel A, Al-Boloushi O, et al (2020) Atmospheric residence times and excess of unsupported 210Po in aerosol samples from the Kuwait bay-northern gulf. Chemosphere 261:127690
Aba A, Uddin S, Bahbahani M, Al-Ghadban A (2014) Radiometric dating of sediment records in Kuwait’s marine area. Journal of Radioanalytical and Nuclear Chemistry 301:247–255
Abdulrahman B, Al-Khayat M, Al-Qattan A, et al (2024) Thermal efficiency and performance analysis of 50 MW concentrated solar power plant. Sustainable Energy Technologies and Assessments 65:103783
Al-Awadhi JM, AlShuaibi AA (2013) Dust fallout in Kuwait city: deposition and characterization. Science of the total environment 461:139–148
Al-Dousari A, Ibrahim M, Al-Dousari N, et al (2018) Pollen in aeolian dust with relation to allergy and asthma in Kuwait. Aerobiologia 34:325–336
Al-Dousari A, Omar A, Al-Hemoud A, et al (2022) A success story in controlling sand and dust storms hotspots in the Middle East. Atmosphere 13:1335
Al-Dousari A, Ramadan A, Al-Qattan A, et al (2020) Cost and effect of native vegetation change on aeolian sand, dust, microclimate and sustainable energy in Kuwait. Journal of Taibah University for Science 14:628–639. https://doi.org/10.1080/16583655.2020.1761662
Al-Dousari AM, Aba A, Al-Awadhi S, et al (2016) Temporal and spatial assessment of pollen, radionuclides, minerals and trace elements in deposited dust within Kuwait. Arab J Geosci 9:95. https://doi.org/10.1007/s12517-015-2182-z
Al-Dousari AM, Alsaleh A, Ahmed M, et al (2019) Off-road vehicle tracks and grazing points in relation to soil compaction and land degradation. Earth systems and environment 3:471–482
Al-Hemoud A, Al-Sudairawi M, Neelamanai S, et al (2017) Socioeconomic effect of dust storms in Kuwait. Arab J Geosci 10:18. https://doi.org/10.1007/s12517-016-2816-9
Anspaugh LR, Shinn JH, Phelps PL, Kennedy NC (1975) Resuspension and Redistribution of Plutonium in Soils. Health Physics 29:
Baccolo G, El Khair DA, Nastasi M, et al (2023) ²¹⁰ Pb _xs. is a viable alternative to ¹³⁷ Cs for tracing soil redistribution in mountain pastures affected by heterogeneous Chernobyl fallout. Earth Surf Processes Landf 48:708–720. https://doi.org/10.1002/esp.5512
Doronzo DM, Al-Dousari A (2019) Preface to dust events in the environment. Sustainability 11:628
Doronzo DM, Al-Dousari A, Folch A, Dagsson-Waldhauserova P (2016) Preface to the dust topical collection. Arabian Journal of Geosciences 9:1–1
Garger E, Hoffman F, Thiessen K, et al (1999) Test of existing mathematical models for atmospheric resuspension of radionuclides. Journal of environmental radioactivity 42:157–175
Garland JA, Cambray RS (1988) Deposition, resuspension and the long term variation of airborne radioactivity from Chernobyl. Section Documentation - CEN/Cadarache, France
Golubenko K, Rozanov E, Kovaltsov G, Usoskin I (2022) Zonal mean distribution of cosmogenic isotope (7Be, 10Be, 14C, and 36Cl) production in stratosphere and troposphere. Journal of Geophysical Research: Atmospheres 127:e2022JD036726
Ismaeel A, Aba A, Al-Shammari H, et al (2020) Activity size distributions of radioactive airborne particles in an arid environment: a case study of Kuwait. Environmental Science and Pollution Research 27:33032–33041
Kajino M, Watanabe A, Ishizuka M, et al (2022) Reassessment of the radiocesium resuspension flux from contaminated ground surfaces in eastern Japan. Atmospheric Chemistry and Physics 22:783–803
Keller G, Bentley SJ, Georgiou IY, et al (2017) River-plume sedimentation and 210 Pb/7 Be seabed delivery on the Mississippi River delta front. Geo-Marine Letters 37:259–272
Kim S, Chang SH, Yim M, Beeley PA (2014) A Preliminary Study on the Resuspension of Radionuclides in Desert Environment. Korean Nuclear Society
AL-Rasheedi Majed, Christian A. Gueymard, Al-Khayat Mohammad, et al (2020) Performance evaluation of a utility-scale dual-technology photovoltaic power plant at the Shagaya Renewable Energy Park in Kuwait. Renewable and Sustainable Energy Reviews 133:110139
Mezina K, Melgunov M, Belyanin D (2020) 7Be, 210Pb and 137Cs in atmospheric deposition of southern and arctic regions of western siberia. RAD Centre, pp 161–166
Miyamoto Y, Yasuda K, Magara M (2014) Size distribution of radioactive particles collected at Tokai, Japan 6 days after the nuclear accident. Journal of environmental radioactivity 132:1–7
Neelamani S, Al-Dousari A (2016) A study on the annual fallout of the dust and the associated elements into the Kuwait Bay, Kuwait. Arabian Journal of Geosciences 9:1–11
Papastefanou C (2008) Radioactive aerosols. Radioactivity in the Environment 12:11–58
Papastefanou C, Ioannidou A, Stoulos S, Manolopoulou M (1995) Atmospheric deposition of cosmogenic 7Be and 137Cs from fallout of the Chernobyl accident. Science of the total environment 170:151–156
Rashid FIA, Zolkaffly MZ (2021) A multi-year study of natural radionuclides Beryllium-7 (Be-7) activity concentrations in surface air in Tanah Rata, Cameron Highlands, Pahang. In: IOP Conference Series: Materials Science and Engineering. IOP Publishing, p 012029
Rosner G, Winkler R (2001) Long-term variation (1986–1998) of post-Chernobyl 90Sr, 137Cs, 238Pu and 239,240 Pu concentrations in air, depositions to ground, resuspension factors and resuspension rates in south Germany. Science of the total environment 273:11–25
Shi Z, Wen A, Yan D, et al (2011) Temporal variation of 7 Be fallout and its inventory in purple soil in the Three Gorges Reservoir region, China. Journal of Radioanalytical and Nuclear Chemistry 288:671–676
Slinn W (1978) Parameterizations for resuspension and for wet and dry deposition of particles and gases for use in radiation dose calculations. Nuclear Safety 19:205–219
Taghavi F, Owlad E, Ackerman S (2017) Enhancement and identification of dust events in the south-west region of Iran using satellite observations. Journal of Earth System Science 126:1–17
Whicker JJ, Breshears DD, McNaughton M, et al (2021) Radionuclide resuspension across ecosystems and environmental disturbances. Journal of Environmental Radioactivity 233:106586
Zheng M, Liu H, Adolphi F, et al (2023) Simulations of 7 Be and 10 Be with the GEOS-Chem global model v14. 0.2 using state-of-the-art production rates. Geoscientific Model Development Discussions 2023:1–29

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published 10 Oct, 2024

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Editorial decision: Accept
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You are reading this latest preprint version

Dust Resuspension Rates in Kuwait: Insights from 7Be and 137Cs Radionuclides

Status:

Journal Publication

Version 1

Abstract

Figures

1. Introduction

2. Materials and Methods

2.1. Study Sites

2.2. Dust Fallout Sampling

2.3. Airborne Radionuclide Activity Concentration

2.4. ⁷Be and ¹³⁷Cs Total Ground Deposition Calculation

2.5. Calculation of Dust Particle Resuspension Rate

2.6. Quality Assurance

3. Results and Discussion

3.1. Average Monthly Depositional Rates and Atmospheric Concentrations of ⁷Be and ¹³⁷Cs

3.2. Dust Particle Resuspension Rate

4. Conclusions

Declarations

Competing Interests:

Ethics approval:

Funding:

Authors contributions:

Acknowledgment

Data availability statement:

References

Status:

Journal Publication

Version 1

Dust Resuspension Rates in Kuwait: Insights from 7Be and 137Cs Radionuclides

Status:

Journal Publication

Version 1

Abstract

Figures

1. Introduction

2. Materials and Methods

2.1. Study Sites

2.2. Dust Fallout Sampling

2.3. Airborne Radionuclide Activity Concentration

2.4. 7Be and 137Cs Total Ground Deposition Calculation

2.5. Calculation of Dust Particle Resuspension Rate

2.6. Quality Assurance

3. Results and Discussion

3.1. Average Monthly Depositional Rates and Atmospheric Concentrations of 7Be and 137Cs

3.2. Dust Particle Resuspension Rate

4. Conclusions

Declarations

Competing Interests:

Ethics approval:

Funding:

Authors contributions:

Acknowledgment

Data availability statement:

References

Status:

Journal Publication

Version 1

2.4. ⁷Be and ¹³⁷Cs Total Ground Deposition Calculation

3.1. Average Monthly Depositional Rates and Atmospheric Concentrations of ⁷Be and ¹³⁷Cs