Atmosphere

17 pages, 9681 KiB

Open AccessArticle

Analysis of the Precipitable Water Vapor Observation in Yunnan–Guizhou Plateau during the Convective Weather System in Summer

by Heng Hu, Yunchang Cao, Chuang Shi, Yong Lei, Hao Wen, Hong Liang, Manhong Tu, Xiaomin Wan, Haishen Wang, Jingshu Liang and Panpan Zhao

Atmosphere 2021, 12(8), 1085; https://doi.org/10.3390/atmos12081085 - 23 Aug 2021

Cited by 3 | Viewed by 2597

Abstract

The ERA5 reanalysis dataset of the European Center for Medium-Range Weather Forecasts (ECMWF) in the summers from 2015 to 2020 was used to compare and analyze the features of the precipitable water vapor (PWV) observed by six ground-based Global Navigation Satellite System (GNSS) [...] Read more.

The ERA5 reanalysis dataset of the European Center for Medium-Range Weather Forecasts (ECMWF) in the summers from 2015 to 2020 was used to compare and analyze the features of the precipitable water vapor (PWV) observed by six ground-based Global Navigation Satellite System (GNSS) meteorology (GNSS/MET) stations in the Yunnan–Guizhou Plateau. The correlation coefficients of the two datasets ranged between 0.804 and 0.878, the standard deviations ranged between 4.686 and 7.338 mm, and the monthly average deviations ranged between −4.153 and 9.459 mm, which increased with the altitude of the station. Matching the quality-controlled ground precipitation data with the PWV in time and space revealed that most precipitation occurred when the PWV was between 30 and 65 mm and roughly met the normal distribution. We used the vertical integral of divergence of moisture flux (∇_p) and S-band Doppler radar networking products combined with the PWV to study the convergence and divergence process and the water vapor delivery conditions during the deep convective weather process from August 24 to 26, 2020, which can be used to analyze the real-time observation capability and continuity of PWV in small-scale and mesoscale weather processes. Furthermore, the 1 h precipitation and the cloud top temperature (ctt) data at the same site were used to demonstrate the effect of PWV on the transit of convective weather systems from different time–space scales. Full article

(This article belongs to the Special Issue Atmospheric Water Vapor Observation, Simulation, Prediction and Responses to Climate Change)

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21 pages, 6129 KiB

Open AccessArticle

Assessment of Outdoor Thermal Comfort in Serbia’s Urban Environments during Different Seasons

by Milica Lukić, Dejan Filipović, Milica Pecelj, Ljiljana Crnogorac, Bogdan Lukić, Lazar Divjak, Ana Lukić and Ana Vučićević

Atmosphere 2021, 12(8), 1084; https://doi.org/10.3390/atmos12081084 - 23 Aug 2021

Cited by 20 | Viewed by 4230

Abstract

The urban microclimate is gradually changing due to climate change, extreme weather conditions, urbanization, and the heat island effect. In such an altered environment, outdoor thermal comfort can have a strong impact on public health and quality of life in urban areas. In [...] Read more.

The urban microclimate is gradually changing due to climate change, extreme weather conditions, urbanization, and the heat island effect. In such an altered environment, outdoor thermal comfort can have a strong impact on public health and quality of life in urban areas. In this study, three main urban areas in Serbia were selected: Belgrade (Central Serbia), Novi Sad (Northern Serbia), and Niš (Southern Serbia). The focus was on the temporal assessment of OTC, using the UTCI over a period of 20 years (1999–2018) during different seasons. The main aim is the general estimation of the OTC of Belgrade, Novi Sad, and Niš, in order to gain better insight into the bioclimatic condition, current trends and anomalies that have occurred. The analysis was conducted based on an hourly (7 h, 14 h, and 21 h CET) and “day by day” meteorological data set. Findings show the presence of a growing trend in seasonal UTCI anomalies, especially during summer and spring. In addition, there is a notable increase in the number of days above the defined UTCI thresholds for each season. Average annual UTCIs values also show a positive, rising trend, ranging from 0.50 °C to 1.33 °C. The most significant deviations from the average UTCI values, both seasonal and annual, were recorded in 2000, 2007, 2012, 2015, 2017, and 2018. Full article

(This article belongs to the Special Issue Outdoor Thermal Comfort in Cities: Assessing and Developing Green, Blue and Grey Solutions for Healthy and Sustainable Urban Future)

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(a) Locations of the studied areas: (1) Belgrade, (2) Novi Sad and (3) Niš; (b) Geographical location of Serbia in Europe <a href="#atmosphere-12-01084-f001" class="html-fig">Figure 1</a>a,b were created using QGIS 3.8 software by OSGeo (Beaverton, OR, USA), based on the Eurostat’ official data sets (<a href="https://ec.europa.eu/eurostat/web/gisco/geodata/reference-data/" target="_blank">https://ec.europa.eu/eurostat/web/gisco/geodata/reference-data/</a> (accessed on 21 May 2021)). Map ratio: 1:1,900,000; projection: WGS 84/UTM, Zone 34N. Altitude structure data of Serbia was obtained by classification of the Digital Elevation Model (DEM) (<a href="https://www.opendem.info/" target="_blank">https://www.opendem.info/</a> (accessed on 22 May 2021)). Full article ">Figure 2
Frequencies of different cold and heat stress category in (a) Belgrade; (b) Novi Sad, and (c) Niš based on UTCI07h (first column), UTCI14h (second column), UTCI21h (third column) during spring, over a period of 20 years (1999–2018). Full article ">Figure 3
Frequencies of different cold and heat stress category in (a) Belgrade; (b) Novi Sad; and (c) Niš based on UTCI07h (first column), UTCI14h (second column), UTCI21h (third column) during summer, over a period of 20 years (1999–2018). Full article ">Figure 4
Frequencies of different cold and heat stress category in (a) Belgrade; (b) Novi Sad and (c) Niš based on UTCI07h (first column), UTCI14h (second column), UTCI21h (third column) during autumn, over a period of 20 years (1999–2018). Full article ">Figure 5
Frequencies of different cold and heat stress category in (a) Belgrade; (b) Novi Sad; and (c) Niš based on UTCI07h (first column), UTCI14h (second column), UTCI21h (third column) during winter, over a period of 20 years (1999–2018). Full article ">Figure 6
Average annual UTCI at 7 h, 14 h and 21 h CET during the period 1999–2018. Blue indicates UTCI values and trends for Belgrade, red is used for Novi Sad, and green for Niš. Full article ">

16 pages, 6109 KiB

Open AccessArticle

Propagation of a Meteotsunami from the Yellow Sea to the Korea Strait in April 2019

by Kyungman Kwon, Byoung-Ju Choi, Sung-Gwan Myoung and Han-Seul Sim

Atmosphere 2021, 12(8), 1083; https://doi.org/10.3390/atmos12081083 - 23 Aug 2021

Cited by 6 | Viewed by 2980

Abstract

A meteotsunami with a wave height of 0.1–0.9 m and a period of 60 min was observed at tide gauges along the Korea Strait on 7 April 2019, while a train of two to four atmospheric pressure disturbances with disturbance heights of 1.5–3.9 [...] Read more.

A meteotsunami with a wave height of 0.1–0.9 m and a period of 60 min was observed at tide gauges along the Korea Strait on 7 April 2019, while a train of two to four atmospheric pressure disturbances with disturbance heights of 1.5–3.9 hPa moved eastward from the Yellow Sea to the Korea Strait. Analysis of observational data indicated that isobar lines of the atmospheric pressure disturbances had angles of 75–83° counterclockwise due east and propagated with a velocity of 26.5–31.0 m/s. The generation and propagation process of the meteotsunami was investigated using the Regional Ocean Modeling System. The long ocean waves were amplified due to Proudman resonance in the southwestern Yellow Sea, where the water is deeper than 75 m; here, the long ocean waves were refracted toward the coast on the shallow coastal region of the northern Korea Strait. Refraction and reflection by offshore islands significantly affect the wave heights at the coast. To investigate the effects of an eastward-moving velocity and angle of atmospheric pressure disturbance on the height of a long ocean wave, sensitivity simulations were performed. This result will be useful for the real-time prediction system of meteotsunamis in the Korea Strait. Full article

(This article belongs to the Special Issue Air-Sea Interaction Processes during Severe Atmospheric and Oceanic Events)

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15 pages, 2921 KiB

Open AccessArticle

Early-Warning Signals of Drought-Flood State Transition over the Dongting Lake Basin Based on the Critical Slowing Down Theory

by Hao Wu, Wei Hou, Dongdong Zuo, Pengcheng Yan and Yuxing Zeng

Atmosphere 2021, 12(8), 1082; https://doi.org/10.3390/atmos12081082 - 23 Aug 2021

Cited by 6 | Viewed by 2532

Abstract

In this study, the standardized precipitation index (SPI) data in Hunan Province from 1961 to 2020 is adopted. Based on the critical slowing down theory, the moving t-test is firstly used to determine the time of drought-flood state transition in the Dongting [...] Read more.

In this study, the standardized precipitation index (SPI) data in Hunan Province from 1961 to 2020 is adopted. Based on the critical slowing down theory, the moving t-test is firstly used to determine the time of drought-flood state transition in the Dongting Lake basin. Afterwards, by means of the variance and autocorrelation coefficient that characterize the phenomenon of critical slowing down, the early-warning signals indicating the drought-flood state in the Dongting Lake basin are explored. The results show that an obvious drought-to-flood (flood-to-drought) event occurred around 1993 (2003) in the Dongting Lake basin in recent 60 years. The critical slowing down phenomena of the increases in the variance and autocorrelation coefficient, which are detected 5–10 years in advance, can be considered as early-warning signals indicating the drought-flood state transition. Through the studies on the drought-flood state and related early-warning signals for the Dongting Lake basin, the reliabilities of the variance and autocorrelation coefficient-based early-warning signals for abrupt changes are demonstrated. It is expected that the wide application of this method could provide important scientific and technological support for disaster prevention and mitigation in the Dongting Lake basin, and even in the middle and lower reaches of the Yangtze River. Full article

(This article belongs to the Special Issue Hydrological Responses under Climate Changes)

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22 pages, 4493 KiB

Open AccessArticle

A Global Empirical Model of the Ion Temperature in the Ionosphere for the International Reference Ionosphere

by Vladimír Truhlík, Dieter Bilitza, Dmytro Kotov, Maryna Shulha and Ludmila Třísková

Atmosphere 2021, 12(8), 1081; https://doi.org/10.3390/atmos12081081 - 23 Aug 2021

Cited by 10 | Viewed by 3902

Abstract

This study presents a suggestion for improvement of the ion temperature (Ti) model in the International Reference Ionosphere (IRI). We have re-examined ion temperature data (primarily available from NASA’s Space Physics Data Facility (SPDF)from older satellites and combined them with newly available data [...] Read more.

This study presents a suggestion for improvement of the ion temperature (Ti) model in the International Reference Ionosphere (IRI). We have re-examined ion temperature data (primarily available from NASA’s Space Physics Data Facility (SPDF)from older satellites and combined them with newly available data from the Defense Meteorological Satellite Program (DMSP), the Communication Navigation Outage Forecasting System (C/NOFS), and from the recently launched Ionospheric Connection Explorer (ICON). We have compiled these data into a unified database comprising in total Ti data from 18 satellites. By comparisons with long term records of ion temperature from the three incoherent scatter radars (ISRs) (Jicamarca, Arecibo, and Millstone Hill), it was found that an intercalibration is needed to achieve consistency with the ISR data and among individual satellite data sets. This database with thus corrected data has been used for the development of a new global empirical model of Ti with inclusion of solar activity variation. This solar activity dependence is represented by an additive correction term to the Ti global pattern. Due to the limited data coverage at altitudes above 1000 km, the altitude range described by the model ranges from 350 km to 850 km covering only the region where generally Ti is higher than the neutral temperature (Tn) and lower than the electron temperature (Te). This approach is consistent with the current description of Ti in the IRI model. However, instead of one anchor point at 430 km altitude as in the current IRI, our approach includes anchor points at 350, 430, 600, and 850 km. At altitudes above 850 km Ti is merged using a gradient derived from the model at 600 and 850 km, with the electron temperature described by the IRI-2016/TBT-2012 option. Comparisons with the ISR data (Jicamarca, Arecibo, Millstone Hill, and Kharkiv) for high and low solar activity and equinox show that the proposed Ti model captures local time variation of Ti at different altitudes and latitudes better than the current IRI-2016 Ti model. Full article

(This article belongs to the Special Issue Ionospheric and Magnetic Signatures of Space Weather Events at Middle and Low Latitudes: Experimental Studies and Modelling)

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26 pages, 5519 KiB

Open AccessEditor’s ChoiceArticle

Adaptive Crop Management under Climate Uncertainty: Changing the Game for Sustainable Water Use

by Soe W. Myint, Rimjhim Aggarwal, Baojuan Zheng, Elizabeth A. Wentz, Jim Holway, Chao Fan, Nancy J. Selover, Chuyuan Wang and Heather A. Fischer

Atmosphere 2021, 12(8), 1080; https://doi.org/10.3390/atmos12081080 - 23 Aug 2021

Cited by 9 | Viewed by 4398

Abstract

Water supplies are projected to become increasingly scarce, driving farmers, energy producers, and urban dwellers towards an urgent and emerging need to improve the effectiveness and the efficiency of water use. Given that agricultural water use is the largest water consumer throughout the [...] Read more.

Water supplies are projected to become increasingly scarce, driving farmers, energy producers, and urban dwellers towards an urgent and emerging need to improve the effectiveness and the efficiency of water use. Given that agricultural water use is the largest water consumer throughout the U.S. Southwest, this study sought to answer two specific research questions: (1) How does water consumption vary by crop type on a metropolitan spatial scale? (2) What is the impact of drought on agricultural water consumption? To answer the above research questions, 92 Landsat images were acquired to generate fine-resolution daily evapotranspiration (ET) maps at 30 m spatial resolution for both dry and wet years (a total of 1095 ET maps), and major crop types were identified for the Phoenix Active Management Area. The study area has a subtropical desert climate and relies almost completely on irrigation for farming. Results suggest that there are some factors that farmers and water managers can control. During dry years, crops of all types use more water. Practices that can offset this higher water use include double or multiple cropping practice, drought tolerant crop selection, and optimizing the total farmed area. Double and multiple cropping practices result in water savings because soil moisture is retained from one planting to another. Further water savings occur when drought tolerant crop types are selected, especially in dry years. Finally, disproportionately large area coverage of high water consuming crops can be balanced and/or reduced or replaced with more water efficient crops. This study provides strong evidence that water savings can be achieved through policies that create incentives for adopting smart cropping strategies, thus providing important guidelines for sustainable agriculture management and climate adaptation to improve future food security. Full article

(This article belongs to the Special Issue Remote Sensing and GIS Applications in Urban Climate Research)

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19 pages, 2355 KiB

Open AccessArticle

Microbiological Contamination Assessment in Higher Education Institutes

by Carla Viegas, Raquel Pimenta, Marta Dias, Bianca Gomes, Miguel Brito, Liliana Aranha Caetano, Elisabete Carolino and Anita Quintal Gomes

Atmosphere 2021, 12(8), 1079; https://doi.org/10.3390/atmos12081079 - 23 Aug 2021

Cited by 9 | Viewed by 4723

Abstract

The higher education sector represents a unique environment and it acts as a work environment, a learning environment for students, and frequently, also a home environment. The aim of this study was to determine the microbial contamination (SARS-CoV-2, fungi, and bacteria) [...] Read more.

The higher education sector represents a unique environment and it acts as a work environment, a learning environment for students, and frequently, also a home environment. The aim of this study was to determine the microbial contamination (SARS-CoV-2, fungi, and bacteria) in Higher Education Facilities (HEI) by using active and passive sampling methods and combining culture-based methods with molecular tools targeting Aspergillus section Fumigati. In addition, the resistance to azole profile was also assessed. Surface samples showed a range of total bacterial contamination between 1 × 10³ to 3.1 × 10⁶ CFU·m⁻², while Gram-negative bacteria ranged from 0 to 1.9 × 10⁴ CFU·m⁻². Fungal contamination ranged from 2 × 10³ to 1.8 × 10⁵ CFU·m⁻² on MEA, and from 5 × 10³ to 1.7 × 10⁵ CFU·m⁻² on DG18. The most prevalent species found on both media was Cladosporium sp. (47.36% MEA; 32.33% DG18). Aspergillus genera was observed on MEA (3.21%) and DG18 (14.66%), but not in the supplemented media used for the azole screening. Aspergillus section Fumigati was detected in 2 air samples (2.22%, 2 out of 90 samples) by qPCR. When testing for SARS-CoV-2 all results were negative. The present study showed that although cleaning and disinfection procedures are done regularly due to the COVID-19 pandemic, being effective in eliminating SARS-CoV-2, surfaces were often contaminated with microorganisms other than SARS-CoV-2. This can be a result of increasing resistance to biocides, and to the wide range of environmental factors that can contribute to the dissemination of microbial contamination indoors. Full article

(This article belongs to the Special Issue Indoor Air Quality—What Is Known and What Needs to Be Done)

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20 pages, 8210 KiB

Open AccessArticle

Computer Simulations of Air Quality and Bio-Climatic Indices for the City of Sofia

by Georgi Gadzhev and Kostadin Ganev

Atmosphere 2021, 12(8), 1078; https://doi.org/10.3390/atmos12081078 - 22 Aug 2021

Cited by 5 | Viewed by 2755

Abstract

Air pollution is responsible for many adverse effects on human beings. Thermal discomfort, on the other hand, is able to overload the human body and eventually provoke health implications due to the heat imbalance. Methods: The aim of the presented work is to [...] Read more.

Air pollution is responsible for many adverse effects on human beings. Thermal discomfort, on the other hand, is able to overload the human body and eventually provoke health implications due to the heat imbalance. Methods: The aim of the presented work is to study the behavior of two bio-climatic indices and statistical characteristics of the air quality index for Sofia city—the capital of Bulgaria for the period 2008–2014. The study is based on the WRF-CMAQ model system simulations with a spatial resolution of 1 km. The air quality is estimated by the air quality index, taking into account the influence of different pollutants and the thermal conditions by two indices, respectively, for hot and cold weather. It was found that the recurrence of both the heat and cold index categories and of the air quality categories have heterogeneous space distribution and well manifested diurnal and seasonal variability. For all of the situations, only O₃ and PM₁₀ are the dominant pollutants—these which determine the AQI category. It was found that AQI1, AQI2, and AQI3, which fall in the “Low” band, have the highest recurrence during the different seasons, up to more than 70% in some places and situations. The recurrence of AQI10 (very high) is rather small—no more than 5% and concentrated in small areas, mostly in the city center. The Heat index of category “Danger” never appears, and the Heat index of category “Extreme caution” appears only in the spring and summer with the highest recurrence of less than 5% in the city center. For the Wind-chill index category, “Very High Risk” never appears, and the category “High Risk” appears with a frequency of about 1–2%. The above leads to the conclusion that both from a point of view of bioclimatic and air quality indices, the human health risks in the city of Sofia are not as high. Full article

(This article belongs to the Special Issue Urban Climate and Air Quality in Mediterranean Cities)

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16 pages, 3133 KiB

Open AccessArticle

Concentrations, Size Distribution, and Community Structure Characteristics of Culturable Airborne Antibiotic-Resistant Bacteria in Xinxiang, Central China

by Xu Yan, Jiahui Ma, Jingyuan Ren, Mengjia Cui, Xinqing Chen, Dezhi Qiu, Miao Lei, Tianning Li, Li Guo, Chun Chen and Yunping Han

Atmosphere 2021, 12(8), 1077; https://doi.org/10.3390/atmos12081077 - 22 Aug 2021

Cited by 5 | Viewed by 2817

Abstract

Antimicrobial resistance is considered an important threat to global health and has recently attracted significant attention from the public. In this study, the concentrations and size distribution characteristics of culturable airborne total bacteria (TB) and four antibiotic-resistant bacteria (tetracycline-resistant bacteria (TRB), ciprofloxacin-resistant bacteria [...] Read more.

Antimicrobial resistance is considered an important threat to global health and has recently attracted significant attention from the public. In this study, the concentrations and size distribution characteristics of culturable airborne total bacteria (TB) and four antibiotic-resistant bacteria (tetracycline-resistant bacteria (TRB), ciprofloxacin-resistant bacteria (CRB), erythromycin-resistant bacteria (ERB), and ampicillin-resistant bacteria (ARB)) were investigated for approximately one year to explore their variations under different seasons, diurnal periods, and air quality levels. The concentrations of TB and four antibiotic-resistant bacteria in winter and night were higher than during other seasons and diurnal periods. Their maximum concentrations were detected from air under moderate pollution or heavy pollution. PM_2.5, PM₁₀, SO₂, and NO₂ were positively related to TB and four antibiotic-resistant bacteria (p < 0.01), whereas O₃ and wind speed were negatively related to them (p < 0.05). The particle size of TB and four antibiotic-resistant bacteria were mainly distributed in stage V (1.1–2.2 µm). Bacillus was the dominant genus of ARB (75.97%) and CRB (25.67%). Staphylococcus and Macrococcus were the dominant genera of TRB (46.05%) and ERB (47.67%), respectively. The opportunistic pathogens of Micrococcus, Sphingomonas, Enterococcus, Rhodococcus, and Stenotrophomonas were also identified. This study provides important references for understanding the threat of bioaerosols to human health. Full article

(This article belongs to the Special Issue Atmospheric Pollution of Agriculture-Dominated Cities)

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Variation of airborne bacteria, antibiotic-resistant bacteria, and PM2.5 during sampling days. Full article ">Figure 2
Size distribution of culturable bacteria and four antibiotic-resistant bacteria under different air quality levels. Full article ">Figure 3
Diurnal variation in size distribution and median diameter of culturable bacteria and four antibiotic-resistant bacteria (the diameter corresponding to a cumulative percentage of 50% is the median diameter (d50)). Full article ">Figure 4
Diurnal variation in particle size distribution of the culturable bacteria and the four antibiotic-resistant bacteria. Full article ">Figure 5
The diversity and relative abundance of the top 50 bacterial genera of four antibiotic-resistant bacteria. Full article ">Figure 6
HQ and HI of airborne bacteria under different diurnal periods, air quality levels, and seasons. (MO: morning; NO: noon; NI: night; EX: excellent; GO: good; SLP: slight pollution; MOP: moderate pollution; HEP: heavy pollution; SP: spring; SU: summer; AU: autumn; WI: winter). Full article ">

16 pages, 13222 KiB

Open AccessArticle

Research on Monthly Precipitation Prediction Based on the Least Square Support Vector Machine with Multi-Factor Integration

by Jingchun Lei, Quan Quan, Pingzhi Li and Denghua Yan

Atmosphere 2021, 12(8), 1076; https://doi.org/10.3390/atmos12081076 - 21 Aug 2021

Cited by 6 | Viewed by 2352

Abstract

Accurate precipitation prediction is of great significance for regional flood control and disaster mitigation. This study introduced a prediction model based on the least square support vector machine (LSSVM) optimized by the genetic algorithm (GA). The model was used to estimate the precipitation [...] Read more.

Accurate precipitation prediction is of great significance for regional flood control and disaster mitigation. This study introduced a prediction model based on the least square support vector machine (LSSVM) optimized by the genetic algorithm (GA). The model was used to estimate the precipitation of each meteorological station over the source region of the Yellow River (SRYE) in China for 12 months. The Ensemble empirical mode decomposition (EEMD) method was used to select meteorological factors and realize precipitation prediction, without dependence on historical data as a training set. The prediction results were compared with each other, according to the determination coefficient (R²), mean absolute errors (MAE), and root mean square error (RMSE). The results show that sea surface temperature (SST) in the Niño 1 + 2 region exerts the largest influence on accuracy of the prediction model for precipitation in the SRYE (

R_{SST}^{2} =

0.856,

{RMSE}_{SST} =

19.648,

{MAE}_{SST} =

14.363). It is followed by the potential energy of gravity waves (Ep) and temperature (T) that have similar effects on precipitation prediction. The prediction accuracy is sensitive to altitude influences and accurate prediction results are easily obtained at high altitudes. This model provides a new and reliable research method for precipitation prediction in regions without historical data. Full article

(This article belongs to the Special Issue Hydrological Responses under Climate Changes)

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Location of the SRYE and the meteorological stations. Full article ">Figure 2
Prediction scheme for precipitation combining with meteorological factors. Full article ">Figure 3
Boxplot of average periods of IMFs in the series of monthly precipitation in 18 meteorological stations. Full article ">Figure 4
Prediction results of precipitation integrating SST, T, and Ep. Full article ">Figure 5
Taylor diagram of precipitation prediction integrating meteorological factors. The blue contours represent Pearson’s correlation coefficient; the green contours indicate RMSE; the black contours denote standard deviation of simulated diagram. Full article ">Figure 6
Parameter optimization based on GA. Full article ">Figure 7
The relationship between prediction accuracy R2 of the model integrating factors and altitude. The blue, red, and black polylines represent the factors Ep, SST, and T, respectively. Full article ">Figure 8
Scatter diagram for the relationship of precipitation with altitude and prediction accuracy R2. Full article ">

19 pages, 5954 KiB

Open AccessArticle

Atmospheric Rivers and Associated Precipitation over France and Western Europe: 1980–2020 Climatology and Case Study

by Benjamin Doiteau, Meredith Dournaux, Nadège Montoux and Jean-Luc Baray

Atmosphere 2021, 12(8), 1075; https://doi.org/10.3390/atmos12081075 - 21 Aug 2021

Cited by 5 | Viewed by 3365

Abstract

Atmospheric rivers are important atmospheric features implicated in the global water vapor budget, the cloud distribution, and the associated precipitation. The ARiD (Atmospheric River Detector) code has been developed to automatically detect atmospheric rivers from water vapor flux and has been applied to [...] Read more.

Atmospheric rivers are important atmospheric features implicated in the global water vapor budget, the cloud distribution, and the associated precipitation. The ARiD (Atmospheric River Detector) code has been developed to automatically detect atmospheric rivers from water vapor flux and has been applied to the ECMWF ERA5 archive over the period 1980–2020 above the Atlantic Ocean and Europe. A case study of an atmospheric river formed in the East Atlantic on August 2014 that reached France has been detailed using ECMWF ERA5 reanalysis, ground based observation data, and satellite products such as DARDAR, AIRS, GPCP, and GOES. This atmospheric river event presents a strong interaction with an intense upper tropospheric jet stream, which induced stratosphere–troposphere exchanges by tropopause fold. A 1980–2020 climatology of atmospheric rivers over Europe has been presented. The west of France, Iberian Peninsula, and British Islands are the most impacted regions by atmospheric rivers with an occurrence of up to four days per month during the October–April period. Up to 40% of the precipitation observed on the west European coast can be linked to the presence of ARs. No significant trend in the occurrence of the phenomena was found over 1980–2020. Full article

(This article belongs to the Special Issue Atmospheric Rivers – Bridging Weather, Climate and Society)

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25 pages, 67320 KiB

Open AccessArticle

Enhancing the Output of Climate Models: A Weather Generator for Climate Change Impact Studies

by Pietro Croce, Paolo Formichi and Filippo Landi

Atmosphere 2021, 12(8), 1074; https://doi.org/10.3390/atmos12081074 - 21 Aug 2021

Cited by 5 | Viewed by 3181

Abstract

Evaluation of effects of climate change on climate variable extremes is a key topic in civil and structural engineering, strongly affecting adaptation strategy for resilience. Appropriate procedures to assess the evolution over time of climatic actions are needed to deal with the inherent [...] Read more.

Evaluation of effects of climate change on climate variable extremes is a key topic in civil and structural engineering, strongly affecting adaptation strategy for resilience. Appropriate procedures to assess the evolution over time of climatic actions are needed to deal with the inherent uncertainty of climate projections, also in view of providing more sound and robust predictions at the local scale. In this paper, an ad hoc weather generator is presented that is able to provide a quantification of climate model inherent uncertainties. Similar to other weather generators, the proposed algorithm allows the virtualization of the climatic data projection process, overcoming the usual limitations due to the restricted number of available climate model runs, requiring huge computational time. However, differently from other weather generation procedures, this new tool directly samples from the output of Regional Climate Models (RCMs), avoiding the introduction of additional hypotheses about the stochastic properties of the distributions of climate variables. Analyzing the ensemble of so-generated series, future changes of climatic actions can be assessed, and the associated uncertainties duly estimated, as a function of considered greenhouse gases emission scenarios. The efficiency of the proposed weather generator is discussed evaluating performance metrics and referring to a relevant case study: the evaluation of extremes of minimum and maximum temperature, precipitation, and ground snow load in a central Eastern region of Italy, which is part of the Mediterranean climatic zone. Starting from the model ensemble of six RCMs, factors of change uncertainty maps for the investigated region are derived concerning extreme daily temperatures, daily precipitation, and ground snow loads, underlying the potentialities of the proposed approach. Full article

(This article belongs to the Topic Climate Change and Environmental Sustainability)

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17 pages, 4419 KiB

Open AccessArticle

Three-Year Variations in Criteria Atmospheric Pollutants and Their Relationship with Rainwater Chemistry in Karst Urban Region, Southwest China

by Jie Zeng, Xin Ge, Qixin Wu and Shitong Zhang

Atmosphere 2021, 12(8), 1073; https://doi.org/10.3390/atmos12081073 - 21 Aug 2021

Cited by 6 | Viewed by 2482

Abstract

Air pollutants have been investigated in many studies, but the variations of atmospheric pollutants and their relationship with rainwater chemistry are not well studied. In the present study, the criteria atmospheric pollutants in nine monitoring stations and rainwater chemistry were analyzed in karst [...] Read more.

Air pollutants have been investigated in many studies, but the variations of atmospheric pollutants and their relationship with rainwater chemistry are not well studied. In the present study, the criteria atmospheric pollutants in nine monitoring stations and rainwater chemistry were analyzed in karst Guiyang city, since the time when the Chinese Ambient Air Quality Standards (CAAQS, third revision) were published. Based on the three-year daily concentration dataset of SO₂, NO₂, CO, PM₁₀ and PM_2.5, although most of air pollutant concentrations were within the limit of CAAQS III-Grade II standard, the significant spatial variations and relatively heavy pollution were found in downtown Guiyang. Temporally, the average concentrations of almost all air pollutants (except for CO) decreased during three years at all stations. Ratios of PM_2.5/PM₁₀ in non- and episode days reflected the different contributions of fine and coarse particles on particulate matter in Guiyang, which was influenced by the potential meteorological factors and source variations. According to the individual air quality index (IAQI), the seasonal variations of air quality level were observed, that is, IAQI values of air pollutants were higher in winter (worst air quality) and lower in summer (best air quality) due to seasonal variations in emission sources. The unique IAQI variations were found during the Chinese Spring Festival. Air pollutant concentrations are also influenced by meteorological parameters, in particular, the rainfall amount. The air pollutants are well scoured by the rainfall process and can significantly affect rainwater chemistry, such as SO₄²⁻, NO₃⁻, Mg²⁺, and Ca²⁺, which further alters the acidification/alkalization trend of rainwater. The equivalent ratios of rainwater SO₄²⁻/NO₃⁻ and Mg²⁺/Ca²⁺ indicated the significant contribution of fixed emission sources (e.g., coal combustion) and carbonate weathering-influenced particulate matter on rainwater chemistry. These findings provide scientific support for air pollution management and rainwater chemistry-related environmental issues. Full article

(This article belongs to the Special Issue Outdoor Air Pollution and Human Health)

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Map of study area. (a) The location of the Guizhou Province; (b) the position of Guiyang city; (c) land use and air quality monitoring stations in Guiyang city. Full article ">Figure 2
(a) The concentration variations of atmospheric SO2 and NO2 at Guiyang city since 2003 and (b) the monthly rainfall amount in 2012, 2013, and 2014. The data source [<a href="#B27-atmosphere-12-01073" class="html-bibr">27</a>,<a href="#B31-atmosphere-12-01073" class="html-bibr">31</a>]. Full article ">Figure 3
Yearly average concentrations of criteria atmospheric pollutants in Guiyang City from 2013 to 2015. Full article ">Figure 4
The seasonal variations of citywide daily mean concentrations of air pollutants in Guiyang city from 2013 to 2015. (a) SO2 and NO2, (b) PM10 and PM2.5, (c) CO. Full article ">Figure 5
The PM2.5/PM10 ratios in non- and episode days at all stations in Guiyang City during 2013–2015, the error bars are standard deviations. Shihuanbaozhan station (SHS), Xinhualu station (XHS), Hongbianmen station (HBS), Maanshan station (MAS), Zhongyuancun station (ZYS), Biyunwo station (BYS), Jianhulu station (JHS), Yanzichong station (YZS), Tongmuling station (TMS). Full article ">Figure 6
Temporal and seasonal variations in IAQI of SO2, NO2, PM10, PM2.5, and CO; S = summer, W = winter. Monthly IAQI values of SO2 (a), NO2 (b), PM10 (c), PM2.5 (d), and CO (e); Seasonal IAQI values of all air pollutants (f). Full article ">Figure 7
The monthly variations of SO42−, NO3−, Mg2+, and Ca2+ concentrations of rainwater and atmospheric SO2, NO2, PM10 + PM2.5 concentrations (a–c), the relationships between atmospheric SO2, NO2, PM10 + PM2.5 concentrations and rainfall amount (d–f), the equivalent ratios of rainwater SO42−/NO3− (g) and Mg2+/Ca2+ (h). The related data sources and reference values are from [<a href="#B27-atmosphere-12-01073" class="html-bibr">27</a>,<a href="#B61-atmosphere-12-01073" class="html-bibr">61</a>]. Full article ">

17 pages, 4831 KiB

Open AccessEditor’s ChoiceArticle

30 Years of Air Quality Trends in Japan

by Akiyoshi Ito, Shinji Wakamatsu, Tazuko Morikawa and Shinji Kobayashi

Atmosphere 2021, 12(8), 1072; https://doi.org/10.3390/atmos12081072 - 21 Aug 2021

Cited by 37 | Viewed by 12264

Abstract

The aim of this paper is to obtain information that will contribute to measures and research needed to further improve the air quality in Japan. The trends and characteristics of air pollutant concentrations, especially PM_2.5, ozone, and related substances, over the past [...] Read more.

The aim of this paper is to obtain information that will contribute to measures and research needed to further improve the air quality in Japan. The trends and characteristics of air pollutant concentrations, especially PM_2.5, ozone, and related substances, over the past 30 years, are analyzed, and the relationships between concentrations and emissions are discussed quantitatively. We found that PM_2.5 mass concentrations have decreased, with the largest reduction in elemental carbon (EC) as the PM_2.5 component. The concentrations of organic carbon (OC) have not changed significantly compared to other components, suggesting that especially VOC emissions as precursors need to be reduced. In addition, the analysis of the differences in PM_2.5 concentrations between the ambient and the roadside showed that further research on non-exhaust particles is needed. For NOx and SO₂, there is a linear relationship between domestic anthropogenic emissions and atmospheric concentrations, indicating that emission control measures are directly effective in the reduction in concentrations. Also, recent air pollution episodes and the effect of reduced economic activity, as a consequence of COVID-19, on air pollution concentrations are summarized. Full article

(This article belongs to the Special Issue Air Pollution in Japan)

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18 pages, 3738 KiB

Open AccessArticle

Variations in the Peczely Macro-Synoptic Types (1881–2020) with Attention to Weather Extremes in the Pannonian Basin

by János Mika, Csaba Károssy and László Lakatos

Atmosphere 2021, 12(8), 1071; https://doi.org/10.3390/atmos12081071 - 20 Aug 2021

Cited by 2 | Viewed by 2013

Abstract

Daily Peczely circulation types are investigated over 140 years (1881–2020). After presenting monthly mean frequencies and durations of the 13 circulation types, two further questions are investigated: (i) How do the circulation types influence local weather extremes?; (ii) Are there significant trends in [...] Read more.

Daily Peczely circulation types are investigated over 140 years (1881–2020). After presenting monthly mean frequencies and durations of the 13 circulation types, two further questions are investigated: (i) How do the circulation types influence local weather extremes?; (ii) Are there significant trends in the frequency of the original and the grouped circulation types in the recent monotonically warming 50 year period (1971–2020)? The answers are as follows: (i) Four local weather extremes were investigated in nine grid-points of the Pannonian Basin and analyzed in the central months of the seasons. It was established that high precipitation and wind maxima occur in almost all circulation types and months, whereas for both high temperature maxima and low temperature minima, there are six circulation types, where no extremity occurred in one, two, or three investigated months. (ii) In the last 50 years, 37% of the linear seasonal frequency trends have been significant. However, these trends are rarely significant in the shorter monotonously warming (1911–1940) and cooling (1941–1970) 30-year periods. Therefore, the significant trends of the last 50 years are unlikely to be the direct consequences of the monotonous hemispherical warming. Since these hemispherical temperature trends are most likely caused by different sets of physical reasons, the reality of the presented circulation frequency trends needs to be validated by climate models. Full article

(This article belongs to the Special Issue Climate Extremes in the Pannonian Basin: Current Approaches and Challenges)

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19 pages, 3412 KiB

Open AccessArticle

Warming Trends of the Upper Troposphere in Taiwan Observed by Radiosonde and Surface Meteorological Stations at Various Altitudes

by Chih-wen Hung and Ming-Fu Shih

Atmosphere 2021, 12(8), 1070; https://doi.org/10.3390/atmos12081070 - 20 Aug 2021

Cited by 1 | Viewed by 2374

Abstract

In recent decades, a more prominent warming trend in the upper troposphere above the tropical western Pacific has been proposed in the literature derived from model simulations, satellite-borne observations, or reanalysis datasets. Rather than applying these “indirect” approaches, this study obtains surface-based and [...] Read more.

In recent decades, a more prominent warming trend in the upper troposphere above the tropical western Pacific has been proposed in the literature derived from model simulations, satellite-borne observations, or reanalysis datasets. Rather than applying these “indirect” approaches, this study obtains surface-based and radiosonde observations in Taiwan in order to investigate long-term changes in temperature at different altitudes within the troposphere under the conditions of ongoing global warming. These surface-based observations indicate more pronounced warming in areas of high terrain, and the radiosondes reveal faster warming trends in the upper troposphere, with the maximum temperature increase between 400 hPa and 250 hPa. The upper-tropospheric warming becomes even more pronounced during boreal winter and spring; however, the intense warming does not carry over near the tropopause. Notable warming is also observed near the surface in Taipei, which may be related to the urban heat island effect caused by the rapid development of anthropic activities. Since Taiwan is located right on the edge of the tropics in the western Pacific, the upper-tropospheric warming, particularly between December and March, above the island should be contributed by the radiative and non-radiative processes, which were previously proposed by other studies. Full article

(This article belongs to the Section Climatology)

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Interannual variations of the (a) annual mean, (b) summer mean, (c) winter mean temperatures based on the CWB conventional weather stations in various groups of altitudes (blue: the surface to 500 m; green: 501 m to 1500 m; red: above 1501 m), unit: °C. (d–f) are same as (a–c) but for the anomaly (applying five-year running mean). The 30-year period of 1961 to 1990 is averaged to produce a mean for the anomaly. Full article ">Figure 2
Radiosonde temperature data availability for every date at each pressure layer from the CWB (a) Taipei and (b) Hualien sounding stations. Black is marked for the date when the data are available. Full article ">Figure 3
Climatological annual cycle of vertical temperature profile over the (a) Taipei sounding station and (b) Hualien sounding station, unit: °C. (c,d) are same as (a,b) but for the anomaly relative to the annual mean. The black lines on 1 May and 1 November denote the transitions of the winter half (from November through next April) and the summer half (from May through October). Full article ">Figure 4
Decadal trend of the (a,b) annual mean temperature at each pressure layer, (c) each group of pressure layers (subtracting the trend value of the first observation year) over the Taipei sounding station, unit: °C. (d–f) are the same as (a–c) but for the Hualien sounding station. The colors indicate the grouped pressure layers (black: the surface to 1000 hPa; blue: 850 hPa to 500 hPa; green: 400 hPa to 250 hPa; red: 200 hPa to 150 hPa). The thin line at each pressure layer denotes the corresponding trend of the variations. Full article ">Figure 5
Same as <a href="#atmosphere-12-01070-f004" class="html-fig">Figure 4</a> but for the winter mean temperature from November to next April. Full article ">Figure 6
Same as <a href="#atmosphere-12-01070-f005" class="html-fig">Figure 5</a> but for the mean temperature from December to next March (DJFM) defined by [<a href="#B17-atmosphere-12-01070" class="html-bibr">17</a>]. Full article ">Figure 7
Decadal trend of the (a,b) mean temperature from December to next March (DJFM) at each pressure layer, (c) each group of pressure layers (subtracting the trend value of the first observation year) through the ERA5 data, unit: °C. The colors indicate the grouped pressure layers (black: 1000 hPa; blue: 850 hPa to 500 hPa; green: 400 hPa to 250 hPa; red: 200 hPa to 150 hPa). The thin line at each pressure layer denotes the corresponding trend of the variations. Full article ">

12 pages, 693 KiB

Open AccessArticle

Bioaerosol Emissions during Organic Waste Treatment for Biopolymer Production: A Case Study

by Erica Pascale, Elena Franchitti, Chiara Caredda, Stefania Fornasero, Giulia Carletto, Biancamaria Pietrangeli, Francesco Valentino, Paolo Pavan, Giorgio Gilli, Elisa Anedda and Deborah Traversi

Atmosphere 2021, 12(8), 1069; https://doi.org/10.3390/atmos12081069 - 20 Aug 2021

Cited by 1 | Viewed by 2839

Abstract

Environmentally sustainable methods of waste disposal are a strategic priority. For organic waste management and innovative biological treatments present advantageous opportunities, although organic waste treatment also includes environmental drawbacks, such as bioaerosol production. This study aims to evaluate bioaerosol spread during an innovative [...] Read more.

Environmentally sustainable methods of waste disposal are a strategic priority. For organic waste management and innovative biological treatments present advantageous opportunities, although organic waste treatment also includes environmental drawbacks, such as bioaerosol production. This study aims to evaluate bioaerosol spread during an innovative experimental treatment. The process consists of two anaerobic steps: acidogenesis, which includes polyhydroxyalkanoate accumulation, followed by methanogenesis. Bioaerosol, PM10, and endotoxin concentrations were measured at three sampling points during different campaigns to evaluate: (1) the background levels, (2) the contamination produced in the pre-treatment stage, and (3) the residual contamination of the outgoing digested sludge. Environmental PM10 seemed to be generally quite contained, while the endotoxin determination was close to 90 EU/m³. Significant microbial concentrations were detected during the loading of the organic fraction of municipal solid waste (fungi > 1300 CFU/m³, Bacillus genus (≈10³ CFU/m³), higher Clostridium spp. and opportunistic human pathogens such as Pseudomonas aeruginosa and Klebsiella pneumoniae), suggesting a significant contamination level. Such results are useful for hazard identification in the risk assessment of innovative processes, as they reveal contaminants potentially harmful to both workers’ health and the environment. Full article

(This article belongs to the Special Issue Occupational Exposure Biological Agents: Focus on a Growing Concern)

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12 pages, 563 KiB

Open AccessEditor’s ChoiceReview

Effects of PM_2.5 on Chronic Airway Diseases: A Review of Research Progress

by Xin Li and Xiaoju Liu

Atmosphere 2021, 12(8), 1068; https://doi.org/10.3390/atmos12081068 - 20 Aug 2021

Cited by 19 | Viewed by 5433

Abstract

The adverse effects of polluted air on human health have been increasingly appreciated worldwide. It is estimated that outdoor air pollution is associated with the death of 4.2 million people globally each year. Accumulating epidemiological studies indicate that exposure to ambient fine particulate [...] Read more.

The adverse effects of polluted air on human health have been increasingly appreciated worldwide. It is estimated that outdoor air pollution is associated with the death of 4.2 million people globally each year. Accumulating epidemiological studies indicate that exposure to ambient fine particulate matter (PM_2.5), one of the important air pollutants, significantly contributes to respiratory mortality and morbidity. PM_2.5 causes lung damage mainly by inducing inflammatory response and oxidative stress. In this paper, we reviewed the research results of our group on the effects of PM_2.5 on chronic obstructive pulmonary disease, asthma, and lung cancer. And recent research progress on epidemiological studies and potential mechanisms were also discussed. Reducing air pollution, although remaining a major challenge, is the best and most effective way to prevent the onset and progression of respiratory diseases. Full article

(This article belongs to the Special Issue Outdoor Air Pollution and Human Health)

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12 pages, 911 KiB

Open AccessArticle

Assessment of Air Pollution Tolerance and Particulate Matter Accumulation of 11 Woody Plant Species

by Huong-Thi Bui, Uuriintuya Odsuren, Kei-Jung Kwon, Sang-Yong Kim, Jong-Cheol Yang, Na-Ra Jeong and Bong-Ju Park

Atmosphere 2021, 12(8), 1067; https://doi.org/10.3390/atmos12081067 - 20 Aug 2021

Cited by 24 | Viewed by 4793

Abstract

High concentration of particulate matter (PM) threatens public health and the environment. Increasing traffic in the city is one of the main factors for increased PM in the air. Urban green spaces play an important role in reducing PM. In this study, the [...] Read more.

High concentration of particulate matter (PM) threatens public health and the environment. Increasing traffic in the city is one of the main factors for increased PM in the air. Urban green spaces play an important role in reducing PM. In this study, the leaf surface and in-wax PM (sPM and wPM) accumulation were compared for 11 plant species widely used for landscaping in South Korea. In addition, biochemical characteristics of leaves (ascorbic acid chlorophyll content, leaf pH, and relative water content) were analyzed to determine air pollution tolerance. Plant species suitable for air quality improvement were selected based on their air pollution tolerance index (APTI) and anticipated performance index (API). Results showed a significant difference according to the accumulation of sPM and wPM and the plant species. PM accumulation and APTI showed a positive correlation. Pinus strobus showed the highest PM accumulation and APTI values, while Cercis chinensis showed the lowest. In 11 plants, API was divided into five groups. Pinus densiflora was classified as the best group, while Cornus officinalis and Ligustrum obtusifolium were classified as not recommended. Full article

(This article belongs to the Section Biosphere/Hydrosphere/Land–Atmosphere Interactions)

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15 pages, 2499 KiB

Open AccessArticle

Copula-Based Drought Monitoring and Assessment According to Zonal and Meridional Temperature Gradients

by Abudureymjang Otkur, Dian Wu, Yin Zheng, Jong-Suk Kim and Joo-Heon Lee

Atmosphere 2021, 12(8), 1066; https://doi.org/10.3390/atmos12081066 - 20 Aug 2021

Cited by 2 | Viewed by 2159

Abstract

Drought is one of the most severe natural disasters. However, many of its characteristic variables have complex nonlinear relationships. Therefore, it is difficult to construct effective drought assessment models. In this study, we analyzed regional drought characteristics in China to identify their relationship [...] Read more.

Drought is one of the most severe natural disasters. However, many of its characteristic variables have complex nonlinear relationships. Therefore, it is difficult to construct effective drought assessment models. In this study, we analyzed regional drought characteristics in China to identify their relationship with changes in meridional and zonal temperature gradients. Drought duration and severity were extracted according to standardized precipitation evapotranspiration index (SPEI) drought grades. Trends in drought duration and severity were detected by the Mann-Kendall test for the period of 1979–2019; they showed that both parameters had been steadily increasing during that time. Nevertheless, the increasing trend in drought severity was particularly significant for northwest and southwest China. A composite analysis confirmed the relationships between drought characteristics and temperature gradients. The northwest areas were relatively less affected by temperature gradients, as they are landlocked, remote from the ocean, and only slightly influenced by the land–ocean thermal contrast (LOC) and the meridional temperature gradient (MTG). The impacts of LOC and MTG on drought duration and severity were positive in the southwest region of China but negative in the northeast. As there was a strong correlation between drought duration and severity, we constructed a 2D copula function model of these parameters. The Gaussian, HuslerReiss, and Frank copula functions were the most appropriate distributions for the northeast, northwest, and southwest regions, respectively. As drought processes are highly complex, the present study explored the internal connections between drought duration and severity and their responses to meteorological conditions. In this manner, an accurate method of predicting future drought events was developed. Full article

(This article belongs to the Special Issue Hydrometeorological Extremes and Its Local Impacts on Human-Environmental Systems)

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Study framework for copula-based drought monitoring and assessment using zonal and meridional circulations. Full article ">Figure 2
Study area comprising the northeastern, northwestern, and southwestern parts of China. Full article ">Figure 3
Definition of drought events used in the present study. Full article ">Figure 4
Time series of global temperature gradients. (a) LOC index. (b) MTG index during the period from 1979 to 2019. Green dotted line represents the linear trend of the indices. Gray dashed line indicates the +1 σ and −1 σ. For each gradient, red dots indicate significant positive events while blue dots indicate significant negative events. Full article ">Figure 5
Composite analysis of drought characteristics with temperature gradients. Full article ">Figure 6
Long-term trend in drought components in China between 1979 and 2019. (a) Drought duration. (b) Drought severity. Full article ">Figure 7
Relationship between drought duration and severity in the (a) southwest, (b) northeast, and (c) southwest. Full article ">Figure 8
Copula distributions of drought duration and severity in positive (negative) LOC/MTG years. Full article ">

18 pages, 21744 KiB

Open AccessArticle

Low-Cost Air Quality Stations’ Capability to Integrate Reference Stations in Particulate Matter Dynamics Assessment

by Lorenzo Brilli, Federico Carotenuto, Bianca Patrizia Andreini, Alice Cavaliere, Andrea Esposito, Beniamino Gioli, Francesca Martelli, Marco Stefanelli, Carolina Vagnoli, Stefania Venturi, Alessandro Zaldei and Giovanni Gualtieri

Atmosphere 2021, 12(8), 1065; https://doi.org/10.3390/atmos12081065 - 19 Aug 2021

Cited by 8 | Viewed by 2735

Abstract

Low-cost air quality stations can provide useful data that can offer a complete picture of urban air quality dynamics, especially when integrated with daily measurements from reference air quality stations. However, the success of such deployment depends on the measurement accuracy and the [...] Read more.

Low-cost air quality stations can provide useful data that can offer a complete picture of urban air quality dynamics, especially when integrated with daily measurements from reference air quality stations. However, the success of such deployment depends on the measurement accuracy and the capability of resolving spatial and temporal gradients within a spatial domain. In this work, an ensemble of three low-cost stations named “AirQino” was deployed to monitor particulate matter (PM) concentrations over three different sites in an area affected by poor air quality conditions. Data of PM_2.5 and PM₁₀ concentrations were collected for about two years following a protocol based on field calibration and validation with a reference station. Results indicated that: (i) AirQino station measurements were accurate and stable during co-location periods over time (R² = 0.5–0.83 and RMSE = 6.4–11.2 μg m⁻³; valid data: 87.7–95.7%), resolving current spatial and temporal gradients; (ii) spatial variability of anthropogenic emissions was mainly due to extensive use of wood for household heating; (iii) the high temporal resolution made it possible to detect time occurrence and strength of PM₁₀ concentration peaks; (iv) the number of episodes above the 1-h threshold of 90 μg m⁻³ and their persistence were higher under urban and industrial sites compared to the rural area. Full article

(This article belongs to the Special Issue PM Sensors for the Measurement of Air Quality)

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Integrated composition of the monitoring area showing: (a) location of the municipality of Capannori within the Tuscany region; (b) location of the three AirQino stations (S15, S16 and S19) and ARPAT station (co-located with S19); (c) air pollution areas identified within the study area. The pictures of each AirQino station and the area of deployment are also shown. Full article ">Figure 2
Boxplot of daily averaged PM10 and PM2.5 concentrations measured by the AirQino stations as compared to ARPAT daily observations during the periods of field calibration for (a) PM10 and (c) PM2.5; field validation for (b) PM10 and (d) PM2.5. Full article ">Figure 3
Annual and seasonal daily cycles observed by the S15-IND, S16-RB, and S19-UB stations across the whole study period: (a,b) yearly cycle of PM10 and PM2.5 concentrations; (c–f) seasonal cycle of PM10 concentrations. Full article ">Figure 4
PM10 daily concentrations observed by ARPAT, S15-IND, S16-RB, and S19-UB stations during the 2018–2019 and 2019–2020 winter periods. The dashed purple line represents the PM10 daily limit value (50 µg m−3). The blue shaded area denotes the co-location period of AirQino stations during the field validation (25 January–20 February 2020). Full article ">Figure 5
Examples of (a) summer and (b) winter daily patterns at high-frequency (10-min) scale of PM10 concentrations observed by S15-IND, S16-RB, and S19-UB stations as compared to those observed at low-frequency (24-h) scale by the ARPAT reference station. The dotted purple line denotes the PM10 daily limit value. Full article ">Figure 6
Detection of PM10 concentration peaks at high-frequency (10-min) scale by the S15-IND, S16-RB, S19-UB stations as compared to the daily values observed by the ARPAT reference station. Examples of further insights by the AirQino stations with respect to the ARPAT station may be observed during both (a,b) no co-location period and (c) co-location period. Full article ">Figure 7
Number of critical episodes and their persistence (i.e., number of consecutive 1-h PM10 concentrations > 90 µg m−3) for S15-IND, S16-RB, S19-UB stations for the period 28 June 2018–15 April 2020. Full article ">

23 pages, 9201 KiB

Open AccessArticle

A Study of Traffic Emissions Based on Floating Car Data for Urban Scale Air Quality Applications

by Felicita Russo, Maria Gabriella Villani, Ilaria D’Elia, Massimo D’Isidoro, Carlo Liberto, Antonio Piersanti, Gianni Tinarelli, Gaetano Valenti and Luisella Ciancarella

Atmosphere 2021, 12(8), 1064; https://doi.org/10.3390/atmos12081064 - 19 Aug 2021

Cited by 5 | Viewed by 2821

Abstract

Urban air quality in cities is strongly influenced by road traffic emissions. Micro-scale models have often been used to evaluate the pollutant concentrations at the scale of the order of meters for estimating citizen exposure. Nonetheless, retrieving emissions information with the required spatial [...] Read more.

Urban air quality in cities is strongly influenced by road traffic emissions. Micro-scale models have often been used to evaluate the pollutant concentrations at the scale of the order of meters for estimating citizen exposure. Nonetheless, retrieving emissions information with the required spatial and temporal details is still not an easy task. In this work, we use our modelling system PMSS (Parallel Micro Swift Spray) with an emission dataset based on Floating Car Data (FCD), containing hourly data for a large number of road links within a 1 × 1 km² domain in the city of Rome for the month of May 2013. The procedures to obtain both the emission database and the PMSS simulations are hosted on CRESCO (Computational Centre for Research on Complex Systems)/ENEAGRID HPC facilities managed by ENEA. The possibility of using such detailed emissions, coupled with HPC performance, represents a desirable goal for microscale modeling that can allow such modeling systems to be employed in quasi-real time and nowcasting applications. We compute NOx concentrations obtained by: (i) emissions coming from prescribed hourly modulations of three types of roads, based on vehicle flux data in the FCD dataset, and (ii) emissions from the FCD dataset integrated into our modelling chain. The results of the simulations are then compared to concentrations measured at an urban traffic station. Full article

(This article belongs to the Special Issue High Performance Computing Serving Atmospheric Transport & Dispersion Modelling)

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28 pages, 7948 KiB

Open AccessEditor’s ChoiceArticle

Fine-Resolution WRF Simulation of Stably Stratified Flows in Shallow Pre-Alpine Valleys: A Case Study of the KASCADE-2017 Campaign

by Michiel de Bode, Thierry Hedde, Pierre Roubin and Pierre Durand

Atmosphere 2021, 12(8), 1063; https://doi.org/10.3390/atmos12081063 - 19 Aug 2021

Cited by 12 | Viewed by 2791

Abstract

In an overall approach aiming at the development and qualification of various tools designed to diagnose and/or forecast the flows at the local scale in complex terrain, we qualified a numerical model based on the WRF platform and operated in a two-way nested [...] Read more.

In an overall approach aiming at the development and qualification of various tools designed to diagnose and/or forecast the flows at the local scale in complex terrain, we qualified a numerical model based on the WRF platform and operated in a two-way nested domain mode, down to a horizontal resolution of 111 m for the smallest domain. The area in question is the Cadarache valley (CV), in southeast France, which is surrounded by hills and valleys of various sizes. The CV dimensions (1 km wide and 100 m deep) favor the development of local flows greatly influenced by the diurnal cycle and are prone to thermal stratification, especially during stable conditions. This cycle was well documented due to permanent observations and dedicated field campaigns. These observations were used to evaluate the performance of the model on a specific day among the intensive observation periods carried out during the KASCADE-2017 campaign. The model reproduced the wind flow and its diurnal cycle well, notably at the local CV scale, which constitutes considerable progress with respect to the performances of previous WRF simulations conducted in this area with kilometric resolution, be it operational weather forecasts or dedicated studies conducted on specific days. The diurnal temperature range is underestimated however, together with the stratification intensity of the cold pool observed at night. Consequently, the slope drainage flows along the CV sidewalls are higher in the simulation than in the observations, and the resulting scalar fields (such as specific humidity) are less heterogeneous in the model than in the observations. Full article

(This article belongs to the Special Issue The Stable Boundary Layer: Observations and Modeling)

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15 pages, 4958 KiB

Open AccessArticle

Evaluation and Projection of Near-Surface Wind Speed over China Based on CMIP6 Models

by Hao Deng, Wei Hua and Guangzhou Fan

Atmosphere 2021, 12(8), 1062; https://doi.org/10.3390/atmos12081062 - 18 Aug 2021

Cited by 20 | Viewed by 3482

Abstract

The characteristics of near-surface wind speed (NWS) are important to the study of dust storms, evapotranspiration, heavy rainfall, air pollution, and wind energy development. This study evaluated the performance of 30 models of the Coupled Model Intercomparison Project Phase 6 (CMIP6) through comparison [...] Read more.

The characteristics of near-surface wind speed (NWS) are important to the study of dust storms, evapotranspiration, heavy rainfall, air pollution, and wind energy development. This study evaluated the performance of 30 models of the Coupled Model Intercomparison Project Phase 6 (CMIP6) through comparison with observational NWS data acquired in China during a historical period (1975–2014), and projected future changes in NWS under three scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5) based on an optimal multi-model ensemble. Results showed that most models reproduced the spatial pattern of NWS for all seasons and the annual mean, although the models generally overestimated NWS magnitude. All models tended to underestimate the trends of decline of NWS for all seasons and the annual mean. On the basis of a comprehensive ranking index, the KIOST-ESM, CNRM-ESM2-1, HadGEM3-GC31-LL, CMCC-CM2-SR5, and KACE-1-0-G models were ranked as the five best-performing models. In the projections of future change, nationally averaged NWS for all months was weaker than in the historical period, and the trends decreased markedly under all the different scenarios except the winter time series under SSP2-4.5. Additionally, the projected NWS over most regions of China weakened in both the early period (2021–2060) and the later period (2061–2100). Full article

(This article belongs to the Special Issue Advances in Understanding, Simulating and Predicting Extreme Climates in Northern Hemisphere)

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12 pages, 4100 KiB

Open AccessArticle

Effect of Mid-Latitude Jet Stream on the Intensity of Tropical Cyclones Affecting Korea: Observational Analysis and Implication from the Numerical Model Experiments of Typhoon Chaba (2016)

by Gunwoo Do and Hyeong-Seog Kim

Atmosphere 2021, 12(8), 1061; https://doi.org/10.3390/atmos12081061 - 18 Aug 2021

Cited by 2 | Viewed by 3438

Abstract

The effect of the jet stream on the changes in the intensity of tropical cyclones (TC) affecting Korea is discussed. We classified the TCs into three categories based on the decreasing rate of TC intensity in 24 h after TC passed 30° N. [...] Read more.

The effect of the jet stream on the changes in the intensity of tropical cyclones (TC) affecting Korea is discussed. We classified the TCs into three categories based on the decreasing rate of TC intensity in 24 h after TC passed 30° N. The TCs with a large intensity decrease had a more vigorous intensity when the TCs approached the mid-latitudes. The analysis of observational fields showed that the strong jet stream over Korea and Japan may intensify TCs by the secondary circulations of jet entrance but induces a large decrease in TC intensity in the mid-latitudes by the strong vertical wind shear. We also performed the numerical simulation for the effect of the jet stream on the intensity changes of Typhoon Chaba (2016). As a result, the stronger jet stream induced more low-level moisture convergence at the south of the jet stream entrance, enhancing the intensity when the TC approached Korea. Furthermore, it induced a rapid reduction in intensity when TC approached in the strong jet stream area. The results suggest that the upper-level jet stream is one of the critical factors modulating the intensity of TC affecting Korea in the vicinity of the mid-latitudes. Full article

(This article belongs to the Section Meteorology)

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10 pages, 1638 KiB

Open AccessArticle

The Effects of Air Quality on Hospital Admissions for Chronic Respiratory Diseases in Petaling Jaya, Malaysia, 2013–2015

by Karyn Morrissey, Ivy Chung, Andrew Morse, Suhanya Parthasarath, Margaret M. Roebuck, Maw Pin Tan, Amanda Wood, Pooi-Fong Wong and Simon P. Frostick

Atmosphere 2021, 12(8), 1060; https://doi.org/10.3390/atmos12081060 - 18 Aug 2021

Cited by 7 | Viewed by 3195

Abstract

This study assesses the impact of a decrease in air quality and the risk of hospital admissions to a public hospital for chronic respiratory diseases for residents of Petaling Jaya, a city in the Greater Kuala Lumpur area in Malaysia. Data on hospital [...] Read more.

This study assesses the impact of a decrease in air quality and the risk of hospital admissions to a public hospital for chronic respiratory diseases for residents of Petaling Jaya, a city in the Greater Kuala Lumpur area in Malaysia. Data on hospital admissions for asthma, bronchitis, emphysema and other chronic obstructive pulmonary disease, weather conditions and the Malaysian Air Pollution Index, a composite indicator of air quality, were collated. An unconstrained distributed lag model to obtain risk of hospitalization for a 10 μg/m³ increase in the API. The lag cumulative effect for a 10 μg/m³ increase in the API was calculated to test for harvesting in the short term. Findings indicate that after an initial decrease in admissions (days 3 and 4), admissions increased again at day 7 and 8 and this relationship was significant. We therefore conclude that a 10 μg/m³ increase has a greater effect on admissions for respiratory health in the short term than a harvesting effect alone would suggest. These results suggest that while air quality is improving in the Greater Kuala Lumpur area, no level of air pollution can be deemed safe. Full article

(This article belongs to the Special Issue Air Pollution and Public Health Effects)

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33 pages, 5798 KiB

Open AccessArticle

Pre-Seismic Irregularities during the 2020 Samos (Greece) Earthquake (M = 6.9) as Investigated from Multi-Parameter Approach by Ground and Space-Based Techniques

by Sudipta Sasmal, Swati Chowdhury, Subrata Kundu, Dimitrios Z. Politis, Stelios M. Potirakis, Georgios Balasis, Masashi Hayakawa and Sandip K. Chakrabarti

Atmosphere 2021, 12(8), 1059; https://doi.org/10.3390/atmos12081059 - 18 Aug 2021

Cited by 47 | Viewed by 4796

Abstract

We present a comprehensive analysis of pre-seismic anomalies as computed from the ground and space-based techniques during the recent Samos earthquake in Greece on 30 October 2020, with a magnitude M = 6.9. We proceed with a multi-parametric approach where pre-seismic irregularities are [...] Read more.

We present a comprehensive analysis of pre-seismic anomalies as computed from the ground and space-based techniques during the recent Samos earthquake in Greece on 30 October 2020, with a magnitude M = 6.9. We proceed with a multi-parametric approach where pre-seismic irregularities are investigated in the stratosphere, ionosphere, and magnetosphere. We use the convenient methods of acoustics and electromagnetic channels of the Lithosphere–Atmosphere–Ionosphere-Coupling (LAIC) mechanism by investigating the Atmospheric Gravity Wave (AGW), magnetic field, electron density, Total Electron Content (TEC), and the energetic particle precipitation in the inner radiation belt. We incorporate two ground-based IGS GPS stations DYNG (Greece) and IZMI (Turkey) for computing the TEC and observed a significant enhancement in daily TEC variation around one week before the earthquake. For the space-based observation, we use multiple parameters as recorded from Low Earth Orbit (LEO) satellites. For the AGW, we use the SABER/TIMED satellite data and compute the potential energy of stratospheric AGW by using the atmospheric temperature profile. It is found that the maximum potential energy of such AGW is observed around six days before the earthquake. Similar AGW is also observed by the method of wavelet analysis in the fluctuation in TEC values. We observe significant energetic particle precipitation in the inner radiation belt over the earthquake epicenter due to the conventional concept of an ionospheric-magnetospheric coupling mechanism by using an NOAA satellite. We first eliminate the particle count rate (CR) due to possible geomagnetic storms and South Atlantic Anomaly (SAA) by the proper choice of magnetic field B values. After the removal of the statistical background CRs, we observe a significant enhancement of CR four and ten days before the mainshock. We use Swarm satellite outcomes to check the magnetic field and electron density profile over a region of earthquake preparation. We observe a significant enhancement in electron density one day before the earthquake. The parameters studied here show an overall pre-seismic anomaly from a duration of ten days to one day before the earthquake. Full article

(This article belongs to the Special Issue Lithosphere–Atmosphere–Ionosphere Coupling (LAIC) Models (Vol. 2))

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21 pages, 11480 KiB

Open AccessArticle

Experimental Analysis of the Influence of Urban Morphological Indices on the Urban Thermal Environment of Zhengzhou, China

by Xuefan Zhou and Hong Chen

Atmosphere 2021, 12(8), 1058; https://doi.org/10.3390/atmos12081058 - 18 Aug 2021

Cited by 7 | Viewed by 2850

Abstract

Summer extreme high-temperatures occur frequently in large cities; urban spatial form is the primary factor affecting the urban thermal environment. Thus, planning and arranging urban spaces is a key approach to regulating urban microclimates. Studies into how urban spatial forms influence the formation [...] Read more.

Summer extreme high-temperatures occur frequently in large cities; urban spatial form is the primary factor affecting the urban thermal environment. Thus, planning and arranging urban spaces is a key approach to regulating urban microclimates. Studies into how urban spatial forms influence the formation of urban microclimates have been carried out for multiple cities in warm and hot regions; however, few studies of this kind have been carried out for cities in cold regions. In this study, we analyze Zhengzhou, a city located in a cold region of China, using summer 2017 measurement data to determine why high temperatures develop in cold areas. We investigated how temperature and humidity vary during the morning, at noon, and in the evening given different land use properties (commercial and residential) and different spatial forms (building height, building density, green coverage rate, and plot ratio); we then studied the correlation between urban spatial form and the urban thermal environment. Our research results indicate that the commercial district’s thermal microclimate was related to PR and BH in the afternoon and GCR in the morning and at night. In the residential district, the key urban morphology factors related to its thermal microclimates were BD, PR, and GCR during almost the whole day. Full article

(This article belongs to the Special Issue The Role of Urban Vegetation Management and Planning in Climate Change Adaptation Strategies)

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8 pages, 731 KiB

Open AccessArticle

²²²Rn Exhalation Rates from Some Granite and Marble Used in Korea: Preliminary Study

by Hyewon Lee, Jungsub Lee, Sungwon Yoon and Cheolmin Lee

Atmosphere 2021, 12(8), 1057; https://doi.org/10.3390/atmos12081057 - 18 Aug 2021

Cited by 4 | Viewed by 2738

Abstract

The objective of this study was to establish a test method for assessing radon exhalation rates from building materials considering radon related environmental policy and research in Korea. This method was established in consideration of cost-effectiveness based on the International Standards Organization (ISO) [...] Read more.

The objective of this study was to establish a test method for assessing radon exhalation rates from building materials considering radon related environmental policy and research in Korea. This method was established in consideration of cost-effectiveness based on the International Standards Organization (ISO) method and the closed chamber method, which is an evaluation method for the emission of hazardous chemical substances from building materials in Korea. The assessment of radon exhalation rates from five types each of granite and marble used in the construction industry in Korea gave mean radon exhalation rates of 0.497 ± 0.467 Bq/m²∙h from granite and 0.193 ± 0.113 Bq/m²∙h from marble, indicating higher radon exhalation rates from granite. These results are consistent with those of a previous study, indicating that granites are more likely to show higher radon exhalation rates than marbles. Full article

(This article belongs to the Special Issue Atmospheric Radon Measurements, Control, Mitigation and Management)

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24 pages, 1900 KiB

Open AccessArticle

Forest Management and Adaptation Strategies in Response to Climate Change by the Taiwanese Public

by Wan-Yu Liu, Chien-Chen Wu and Shih-Yu Simon Wang

Atmosphere 2021, 12(8), 1056; https://doi.org/10.3390/atmos12081056 - 17 Aug 2021

Cited by 5 | Viewed by 3166

Abstract

Forests account for 60% of lands in Taiwan. Climate change impacts forests in many aspects and is increasingly likely to undermine the ability of forests to provide basic ecosystem services. To help reduce the impact of climate change on Taiwan’s forests, people must [...] Read more.

Forests account for 60% of lands in Taiwan. Climate change impacts forests in many aspects and is increasingly likely to undermine the ability of forests to provide basic ecosystem services. To help reduce the impact of climate change on Taiwan’s forests, people must be made aware of the relationship between climate change and forests. Based on questionnaires collected from 17 cities in Taiwan, this study applied spatial analysis to assess the respondents’ understanding of climate change and adaptation strategies for forest management. A total of 650 questionnaires were distributed and 488 valid ones were collected. The results show that (1) Most respondents believe that climate change is true and more than half of the respondents have experienced extreme weather events, especially extreme rainfall; (2) Most respondents believe that climate change will affect Taiwan’s forests with the majority recognizing the increasing impact of extreme events being the primary cause, followed by changes in the composition of tree species and the deterioration of forest adaptability due to climate change; (3) Most respondents expressed that forest management should be adjusted for climate change and called for measures being taken to establish mixed forests as well as monitoring forest damage; (4) In order to address the difficulties faced by forest owners on the impact of climate change, the majority of respondents felt that the government should raise forest owners’ understanding on climate change and adaptation policies, while the subsidy incentives must also be adjusted. The results of this study show that the respondents do realize the importance of climate change and forest management so much so their awareness in this matter led to their support for forest adaptation measures and policies. Full article

(This article belongs to the Special Issue Climate Change and Forest Environment)

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