Previous Issue
Volume 11, June

Table of Contents

Atmosphere, Volume 11, Issue 7 (July 2020) – 53 articles

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Order results
Result details
Select all
Export citation of selected articles as:
Open AccessArticle
Fast Warming Has Accelerated Snow Cover Loss during Spring and Summer across the Northern Hemisphere over the Past 52 Years (1967–2018)
Atmosphere 2020, 11(7), 728; https://doi.org/10.3390/atmos11070728 (registering DOI) - 08 Jul 2020
Abstract
With snow cover changing worldwide in several worrisome ways, it is imperative to determine both the variability in snow cover in greater detail and its relationship with ongoing climate change. Here, we used the satellite-based snow cover extent (SCE) dataset of National Oceanic [...] Read more.
With snow cover changing worldwide in several worrisome ways, it is imperative to determine both the variability in snow cover in greater detail and its relationship with ongoing climate change. Here, we used the satellite-based snow cover extent (SCE) dataset of National Oceanic and Atmospheric Administration (NOAA) to detect SCE variability and its linkages to climate over the 1967–2018 periods across the Northern Hemisphere (NH). Interannually, the time series of SCE across the NH reveal a substantial decline in both spring and summer (−0.54 and −0.71 million km2/decade, respectively), and this decreasing trend corresponded with rising spring and summer temperatures over high-latitude NH regions. Among the four seasons, the temperature rise over the NH was the highest in winter (0.39 °C/decade, p < 0.01). More precipitation in winter was closely related to an increase of winter SCE in mid-latitude areas of NH. Summer precipitation over the NH increased at a significant rate (1.1 mm/decade, p < 0.01), which likely contribute to the accelerated reduction of summer’s SCE across the NH. However, seasonal sensitivity of SCE to temperature changes differed between the Eurasian and North American continents. Thus, this study provides a better understanding of seasonal SCE variability and climatic changes that occurred at regional and hemispheric spatial scales in the past 52 years. Full article
(This article belongs to the Section Climatology)
Show Figures

Figure 1

Open AccessArticle
UV-Index Climatology for Europe Based on Satellite Data
Atmosphere 2020, 11(7), 727; https://doi.org/10.3390/atmos11070727 (registering DOI) - 08 Jul 2020
Abstract
The UV-Index (UVI) is aimed at the prevention of skin cancer as well as other negative implications of ultraviolet radiation exposure. In order to support health related applications, assessments and planning that rely on long term data in high spatial resolution and as [...] Read more.
The UV-Index (UVI) is aimed at the prevention of skin cancer as well as other negative implications of ultraviolet radiation exposure. In order to support health related applications, assessments and planning that rely on long term data in high spatial resolution and as there exist only limited ground-based measurements, satellite products from reliable atmospheric monitoring services are used as sustainable data sources to create a climatology of the UVI at the local noon. In this study, the (all-sky) UVI as well as the hypothetically clear-sky UVI were analysed for the European region from 30° North to 65° North and from 25° West to 35° East in a spatial resolution of 0.05° for the time period 1983 to 2015. Maps of the monthly mean UVI provide an overview of the distribution of UVI for Europe as well as the spatial and temporal differences and regional variability at local solar noon. Additionally, eight selected locations provide insight into the effects of latitude and altitude on UVI in Europe. Monthly boxplots for each location provide information about regional differences in the variability of UVI, showing maximum variability in Northern and Central Europe in summer, where in Southern Europe this basically occurs in spring. The frequency of the World Health Organization exposure categories moderate, high and very high UVI is provided based on ten-day means for each month. The maximum difference between mean values per decade of 2006–2015 compared to 1983–1992 ranges from −1.2 to +1.2 for UVI and from −0.4 to +0.6 for UVI c l e a r s k y . All locations, except the Northern European site, show an increase of UVI during spring and early summer months. A statistically significant increase in the annual mean all-sky UVI has been found for four sites, which ranges from +1.2% to +3.6% per decade. The latest eleven-year period of the UVI climatology (2005–2015) has been validated with UVI measured in five sites. The sites that are located north of the Alps show an underestimation of the UVI, likely due to the cloud modification. In the south, the UVI climatology provides values that are on average overestimated, possibly related to the use of climatological aerosol information. For the site within the Alps, a switch between underestimation and overestimation during the course of the year has been found. 7% to 9% of the UVI values of the climatology differ from the measured UVI by more than one unit. Full article
(This article belongs to the Special Issue Challenges in Applied Human Biometeorology)
Show Figures

Figure 1

Open AccessArticle
Influence of Novaya Zemlya Bora on Sea Waves: Satellite Measurements and Numerical Modeling
Atmosphere 2020, 11(7), 726; https://doi.org/10.3390/atmos11070726 - 07 Jul 2020
Viewed by 107
Abstract
This paper investigates for the first time sea waves during Novaya Zemlya bora—a downslope windstorm on the western coast of the archipelago during eastern winds—using a statistical and case-study approach. Statistical analysis of altimeter data off the western coast of Novaya Zemlya during [...] Read more.
This paper investigates for the first time sea waves during Novaya Zemlya bora—a downslope windstorm on the western coast of the archipelago during eastern winds—using a statistical and case-study approach. Statistical analysis of altimeter data off the western coast of Novaya Zemlya during bora shows that, despite strong wind forcing, the frequency of hazard wave heights was low due to the limited fetch. This result was confirmed by the high-resolution numerical simulations of two severe bora episodes. However, the influence of bora on sea waves in some cases was significant: bora increased wave height at a distance from shore greater than 200 km and wave height anomaly was up to 2–3 m. The influence of the wind input parametrization choice during bora is great in the coastal region; however, parametrizations with fetch-limited modifications and strong-wind adopted aerodynamic drag coefficient do not improve the modeling results in the open sea where altimeter data are available. Full article
(This article belongs to the Special Issue Atmospheric Processes Shaping Polar Climate)
Open AccessArticle
Coastal Resilience Against Storm Surge from Tropical Cyclones
Atmosphere 2020, 11(7), 725; https://doi.org/10.3390/atmos11070725 - 07 Jul 2020
Viewed by 103
Abstract
It is well known that seawalls are effective at stopping common storm surges in urban areas. This paper examines whether seawalls should be built to withstand the storm surge from a major tropical cyclone. We estimate the extra cost of building the wall [...] Read more.
It is well known that seawalls are effective at stopping common storm surges in urban areas. This paper examines whether seawalls should be built to withstand the storm surge from a major tropical cyclone. We estimate the extra cost of building the wall tall enough to stop such surges and the extra flood benefit of this additional height. We estimate the surge probability distribution from six tidal stations spread along the Atlantic seaboard of the United States. We then measure how valuable the vulnerable buildings behind a 100 m wall must be to justify such a tall wall at each site. Combining information about the probability distribution of storm surge, the average elevation of protected buildings, and the damage rate at each building, we find that the value of protected buildings behind this 100 m wall must be in the hundreds of millions to justify the wall. We also examine the additional flood benefit and cost of protecting a km2 of land in nearby cities at each site. The density of buildings in coastal cities in the United States are generally more than an order of magnitude too low to justify seawalls this high. Seawalls are effective, but not at stopping the surge damage from major tropical cyclones. Full article
(This article belongs to the Special Issue Modeling and Data Assimilation for Tropical Cyclone Forecasts)
Open AccessArticle
Investigation of the Weather Conditions During the Collapse of the Morandi Bridge in Genoa on 14 August 2018 Using Field Observations and WRF Model
Atmosphere 2020, 11(7), 724; https://doi.org/10.3390/atmos11070724 - 07 Jul 2020
Viewed by 177
Abstract
On 14 August 2018, Morandi Bridge in Genoa, Italy, collapsed to the ground that was 40 m below. This tragedy killed 43 people. Preliminary investigations indicated poor design, questionable building practices, and insufficient maintenance—or a combination of these factors—as a possible cause of [...] Read more.
On 14 August 2018, Morandi Bridge in Genoa, Italy, collapsed to the ground that was 40 m below. This tragedy killed 43 people. Preliminary investigations indicated poor design, questionable building practices, and insufficient maintenance—or a combination of these factors—as a possible cause of the collapse. However, around the collapse time, a thunderstorm associated with strong winds, lightning, and rain also developed over the city. While it is unclear if this thunderstorm played a role in the collapse, the present study examines the weather conditions before and during the bridge collapse. The study particularly focuses on the analysis of a downburst that was observed around the collapse time and a few kilometers away from the bridge. Direct and remote sensing measurements are used to describe the evolution of the thunderstorm during its approached from the sea to the city. The Doppler lidar measurements allowed the reconstruction of the gust front shape and the evaluation of its displacement velocity of 6.6 m s−1 towards the lidar. The Weather Research and Forecasting simulations highlighted that it is still challenging to forecast localized thunderstorms with operational setups. The study has shown that assimilation of radar reflectivity improves the timing and reconstruction of the gust front observed by local measurements. Full article
(This article belongs to the Section Meteorology)
Show Figures

Figure 1

Open AccessArticle
Evaluation of Historical CMIP5 GCM Simulation Results Based on Detected Atmospheric Teleconnections
Atmosphere 2020, 11(7), 723; https://doi.org/10.3390/atmos11070723 - 07 Jul 2020
Viewed by 104
Abstract
Atmospheric teleconnections are characteristic to the climate system and exert major impacts on the global and regional climate. Accurate representation of teleconnections by general circulation models (GCMs) is indispensable given their fundamental role in the large scale circulation patterns. In this study a [...] Read more.
Atmospheric teleconnections are characteristic to the climate system and exert major impacts on the global and regional climate. Accurate representation of teleconnections by general circulation models (GCMs) is indispensable given their fundamental role in the large scale circulation patterns. In this study a statistical method is introduced to evaluate historical GCM outputs of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) with respect to teleconnection patterns. The introduced method is based on the calculation of correlations between gridded time series of the 500 hPa geopotential height fields in the Northern Hemisphere. GCMs are quantified by a simple diversity index. Additionally, potential action centers of the teleconnection patterns are identified on which the local polynomial regression model is fitted. Diversity fields and regression curves obtained from the GCMs are compared against the NCEP/NCAR Reanalysis 1 and the ERA-20C reanalysis datasets. The introduced method is objective, reproducible, and reduces the number of arbitrary decisions during the analysis. We conclude that major teleconnection patterns are positioned in the GCMs and in the reanalysis datasets similarly, however, spatial differences in their intensities can be severe in some cases that could hamper the applicability of the GCM results for some regions. Based on the evaluation method, best-performing GCMs can be clearly distinguished. Evaluation of the GCMs based on the introduced method might help the modeling community to choose GCMs that are the most applicable for impact studies and for regional downscaling exercises. Full article
Show Figures

Figure 1

Open AccessArticle
Atmospheric Aerosol Distribution in 2016–2017 over the Eastern European Region Based on the GEOS-Chem Model
Atmosphere 2020, 11(7), 722; https://doi.org/10.3390/atmos11070722 - 07 Jul 2020
Viewed by 206
Abstract
The spatial and temporal distributions of atmospheric aerosols have been simulated using the GEOS-Chem model over the sparsely investigated Eastern European region. The spatial distribution of the particulate matter (PM2.5) concentration, mineral dust, black carbon, organic aerosols, sea salt, as well [...] Read more.
The spatial and temporal distributions of atmospheric aerosols have been simulated using the GEOS-Chem model over the sparsely investigated Eastern European region. The spatial distribution of the particulate matter (PM2.5) concentration, mineral dust, black carbon, organic aerosols, sea salt, as well as nitrate, sulfate, and ammonium aerosols during 2016–2017 were considered. The aerosols’ concentration, seasonality and spatial features were determined for the region. Particulate matter (PM2.5) contamination prevails in Poland in late autumn and winter. The monthly mean PM2.5 concentration reached 55 µg m−3 over the Moscow region in the early spring of both years. The mineral dust concentration varied significantly, reaching 40 µg m−3 over the southwestern part of Eastern Europe in March 2016. The areas most polluted by black carbon aerosols were the central and southern parts of Poland in the winter. The organic aerosols’ concentration was the largest in March and April, reaching 10 µg m−3 over East Belarus. The sea salt aerosol concentration increased in the coastal regions in winter due to the wind strength. Mineral dust aerosols in Eastern Europe are mainly composed of dust, partially transported from the Ukrainian steppe and partially from the Saharan Desert. Full article
(This article belongs to the Section Aerosols)
Show Figures

Figure 1

Open AccessArticle
A Combined Citizen Science—Modelling Approach for NO2 Assessment in Torino Urban Agglomeration
Atmosphere 2020, 11(7), 721; https://doi.org/10.3390/atmos11070721 - 06 Jul 2020
Viewed by 244
Abstract
The #CHEARIATIRA citizen science campaign was developed in February 2019 in Torino (western part of the Po Valley megacity region). The aim of the campaign was public engagement with measuring NO2 concentrations in an urban area that often exceeds air quality standards. [...] Read more.
The #CHEARIATIRA citizen science campaign was developed in February 2019 in Torino (western part of the Po Valley megacity region). The aim of the campaign was public engagement with measuring NO2 concentrations in an urban area that often exceeds air quality standards. NO2 diffusion tubes were employed by citizens under our supervision. In this paper, we present the main outcomes of a combined approach between the #CHEARIATIRA campaign and the urban dispersion model SIRANE. The results were validated against the available public Air Quality Monitoring Stations (AQMS). The citizens’ passive samplers and the modelled data show a good response in central districts both during the campaign interval and by annual projection. Traffic hotspots and sensitive receptors (schools, hospital) have high concentrations of NO2. Most of the study area (83% of the tubes) is subject to an increased risk of premature death according to epidemiological literature. Full article
Show Figures

Graphical abstract

Open AccessArticle
Characterization and Source Apportionment of Fine Particles during a Heavy Pollution Episode over the Yangtze River Delta, China
Atmosphere 2020, 11(7), 720; https://doi.org/10.3390/atmos11070720 - 06 Jul 2020
Viewed by 144
Abstract
Regional-scale field observations of fine particles (PM2.5) were carried out at urban, suburban and regional background sites across the Yangtze River Delta (YRD) from 15–30 January 2015. The coefficients of divergence (CD) values reveal the similarity of dataset at the three [...] Read more.
Regional-scale field observations of fine particles (PM2.5) were carried out at urban, suburban and regional background sites across the Yangtze River Delta (YRD) from 15–30 January 2015. The coefficients of divergence (CD) values reveal the similarity of dataset at the three sites. The PM2.5 concentrations and meteorological data exhibit temporal synchronization. From January 15 to 26, the YRD experienced severe PM2.5 pollution resulting from a cold front moving through and high-pressure control. Then, a 4-day intermittent rain event from 27–30 January significantly scavenged PM2.5. For the chemical components in PM2.5, secondary inorganic ions were dominant, and they accounted for larger proportions at the urban and suburban sites than at the regional background site. The OC/EC ratios were higher in daytime than at night, and were lower on polluted days than on clean (rainy) days. The principal sources of PM2.5 were secondary nitrate (38%) and sulfate (23%) formation, biomass burning (14%), and marine source (8%). Marine (16%) and sulfate (30%) sources were enhanced on clean (rainy) days, indicating the notable effect of marine air masses on PM2.5 chemical components. The open burning source contribution at the regional site was the largest during the polluted period because more air masses arrived from combustion zones. Full article
(This article belongs to the Section Aerosols)
Show Figures

Graphical abstract

Open AccessCommunication
A Collaborative Training Program to Assess Mercury Pollution from Gold Shops in Guyana’s Artisanal and Small-Scale Gold Mining Sector
Atmosphere 2020, 11(7), 719; https://doi.org/10.3390/atmos11070719 - 06 Jul 2020
Viewed by 172
Abstract
A three-phase, 11-day training program designed to monitor elemental mercury (Hg0) emissions originating from gold shops was conducted in Georgetown and Bartica, Guyana, during May of 2019. The first phase consisted of interactive lectures and discussions on mercury use in artisanal [...] Read more.
A three-phase, 11-day training program designed to monitor elemental mercury (Hg0) emissions originating from gold shops was conducted in Georgetown and Bartica, Guyana, during May of 2019. The first phase consisted of interactive lectures and discussions on mercury use in artisanal and small-scale gold mining throughout Guyana, the region, and the world. In addition, specific training in the theory and use of analytical instrumentation to quantify Hg0 pollution associated with the processing of amalgams and sponge gold occurred. Trainees participated in the mapping of smelting facilities in Georgetown where, outside of one gold shop, Hg0 concentrations exceeded 100,000 ng/m3. During the second phase of training, a subset of trainees traveled to Bartica, where they mapped the town center to identify point sources of Hg0 pollution, all of which corresponded to the location of shops where amalgams and sponge gold were heated and purchased. Once mapped, Hg0 concentrations were measured during the smelting of gold inside the Guyana Gold Board (GGB) facility and two privately-owned gold shops. Maximum Hg0 concentrations at the GGB facility did not exceed 98,700 ng/m3 during the measurement period, while maximum concentrations at the two privately owned shops were measured as 527,500 ng/m3 and 302,200 ng/m3. With guidance from the training team, trainees were responsible for the collection and interpretation of all data. The third phase of the training involved the collaborative production of a report summarizing the findings from the training. This work represents the first formal training opportunity for the assessment of Hg0 concentrations in and around gold shops in Guyana, and provides baseline data to assist the government of Guyana to generate air quality standards for Hg0 emissions. Full article
Show Figures

Graphical abstract

Open AccessArticle
Exposure to Indoor Volatile Organic Compounds and Hypertension among Thin Film Transistor Liquid Crystal Display Workers
Atmosphere 2020, 11(7), 718; https://doi.org/10.3390/atmos11070718 - 06 Jul 2020
Viewed by 161
Abstract
This cross-sectional study aimed to determine the concentration of indoor volatile organic compounds (VOCs) and to investigate the association between indoor VOCs exposure and the prevalence of hypertension among thin film transistor liquid crystal display (TFT-LCD) workers. A total of 20 canisters were [...] Read more.
This cross-sectional study aimed to determine the concentration of indoor volatile organic compounds (VOCs) and to investigate the association between indoor VOCs exposure and the prevalence of hypertension among thin film transistor liquid crystal display (TFT-LCD) workers. A total of 20 canisters were used to collect VOCs samples in the array, cell and module areas over 12 hours and VOCs concentrations were analyzed by the gas chromatography with mass spectrum. Individual information of health examination and lifestyles by self-administrated questionnaire were provided by 155 volunteers. The multivariate regression models were used to evaluate the associations between VOCs exposure, blood pressure and the prevalence of hypertension. The four dominant VOCs were ethanol (1870.8 ± 1754.0 ppb), acetone (689.9 ± 587.4 ppb), isopropyl alcohol (177.1 ± 202.3 ppb) and propylene glycol monomethyl ether acetate (98.2 ± 100.8 ppb), which were identified with the highest level in the module area for ethanol and acetone and in the array area for the others. Subjects exposed to a total level of ethanol, cyclohexanone and toluene ≥ 2500 ppb had an increased systolic blood pressure of 5.95 mmHg (95% confidence interval: 0.20–11.71; p = 0.043) compared with those exposed to <2500 ppb. Exposure to mixed VOCs in the indoor environment might be associated with elevated blood pressure among TFT-LCD workers. Full article
(This article belongs to the Special Issue Impacts of Indoor Air Pollution on Cardiopulmonary System)
Open AccessArticle
Summer Monsoon Season Streamflow Variations in the Middle Yellow River since 1570 CE Inferred from Tree Rings of Pinus tabulaeformis
Atmosphere 2020, 11(7), 717; https://doi.org/10.3390/atmos11070717 - 06 Jul 2020
Viewed by 323
Abstract
This study investigates the potential reconstruction of summer monsoon season streamflow variations in the middle reaches of the Yellow River from tree rings in the Qinling Mountains. The regional chronology is significantly positively correlated with the July–October streamflow of the middle Yellow River [...] Read more.
This study investigates the potential reconstruction of summer monsoon season streamflow variations in the middle reaches of the Yellow River from tree rings in the Qinling Mountains. The regional chronology is significantly positively correlated with the July–October streamflow of the middle Yellow River from 1919 to 1949, and the derived reconstruction explains 36.4% of the actual streamflow variance during this period. High streamflows occurred during 1644–1757, 1795–1806, 1818–1833, 1882–1900, 1909–1920 and 1933–1963. Low streamflows occurred during 1570–1643, 1758–1794, 1807–1817, 1834–1868, 1921–1932 and 1964–2012. High and low streamflow intervals also correspond well to the East Asian summer monsoon (EASM) intensity. Some negative correlations of our streamflow reconstruction with Indo-Pacific sea surface temperature (SST) also suggest the linkage of regional streamflow changes to the Asian summer monsoon circulation. Although climate change has some important effects on the variation in streamflow, anthropogenic activities are the primary factors mediating the flow cessation of the Yellow River, based on streamflow reconstruction. Full article
(This article belongs to the Special Issue Past Climate Reconstructed from Tree Rings)
Show Figures

Figure 1

Open AccessArticle
Gathering Pipeline Methane Emissions in Utica Shale Using an Unmanned Aerial Vehicle and Ground-Based Mobile Sampling
Atmosphere 2020, 11(7), 716; https://doi.org/10.3390/atmos11070716 - 05 Jul 2020
Viewed by 217
Abstract
The United States Environmental Protection Agency Greenhouse Gas Inventory only recently updated the emission factors of natural gas gathering pipelines in April 2019 from the previous estimates based on a 1990s study of distribution pipelines. Additional measurements are needed from different basins for [...] Read more.
The United States Environmental Protection Agency Greenhouse Gas Inventory only recently updated the emission factors of natural gas gathering pipelines in April 2019 from the previous estimates based on a 1990s study of distribution pipelines. Additional measurements are needed from different basins for more accurate assessments of methane emissions from natural gas midstream industries and hence the overall climate implications of natural gas as the interim major energy source for the next decade. We conducted an unmanned aerial vehicle (UAV) survey and a ground-based vehicle sampling campaign targeting gathering pipeline systems in the Utica Shale from March to April in 2019. Out of 73 km of pipeline systems surveyed, we found no leaks on pipelines and two leaks on an accessory block valve with leak rates of 3.8 ± 0.4 and 7.6 ± 0.8 mg/s. The low leak frequency phenomenon was also observed in the only existing gathering pipeline study in Fayetteville Shale. The UAV sampling system facilitated ease of access, broadened the availability of pipelines for leak detection, and was estimated to detect methane leaks down to 0.07 g/s using Gaussian dispersion modeling. For future UAV surveys adopting similar instrument setup and dispersion models, we recommend arranging controlled release experiments first to understand the system’s detection limit and choosing sampling days with steady and low wind speeds (2 m/s). Full article
Show Figures

Graphical abstract

Open AccessArticle
Gas-Phase Reaction of trans-2-Methyl-2-butenal with Cl: Kinetics, Gaseous Products, and SOA Formation
Atmosphere 2020, 11(7), 715; https://doi.org/10.3390/atmos11070715 - 05 Jul 2020
Viewed by 175
Abstract
The gas-phase reaction between trans-2-methyl-2-butenal and chlorine (Cl) atoms has been studied in a simulation chamber at 298 ± 2 K and 760 ± 5 Torr of air under free-NOx conditions. The rate coefficient of this reaction was determined as k [...] Read more.
The gas-phase reaction between trans-2-methyl-2-butenal and chlorine (Cl) atoms has been studied in a simulation chamber at 298 ± 2 K and 760 ± 5 Torr of air under free-NOx conditions. The rate coefficient of this reaction was determined as k = (2.45 ± 0.32) × 10−10 cm3 molecule−1 s−1 by using a relative method and Fourier transform infrared spectroscopy. In addition to this technique, gas chromatography coupled to mass spectrometry and proton transfer time-of-flight mass spectrometry were used to detect and monitor the time evolution of the gas-phase reaction products. The major primary reaction product from the addition of Cl to the C-3 of trans-2-methyl-2-butenal was 3-chloro-2-butanone, with a molar yield (YProd) of (52.5 ± 7.3)%. Acetaldehyde (Y = (40.8 ± 0.6)%) and HCl were also identified, indicating that the H-abstraction by Cl from the aldehyde group is a reaction pathway as well. Secondary organic aerosol (SOA) formation was investigated by using a fast mobility particle sizer spectrometer. The SOA yield in the Cl + trans-2-methyl-2-butenal reaction is reported to be lower than 2.4%, thus its impact can be considered negligible. The atmospheric importance of the titled reaction is similar to the corresponding OH reaction in areas with high Cl concentration. Full article
Show Figures

Figure 1

Open AccessArticle
Investigation of Aerosol Climatology, Optical Characteristics and Variability over Egypt Based on Satellite Observations and In-Situ Measurements
Atmosphere 2020, 11(7), 714; https://doi.org/10.3390/atmos11070714 - 03 Jul 2020
Viewed by 230
Abstract
Egypt experiences high rates of air pollution, which is a major threat to human health and the eco-environment and therefore needs to be tackled by defining major causes to hinder or mitigate their impacts. The major driving forces of air pollution are either [...] Read more.
Egypt experiences high rates of air pollution, which is a major threat to human health and the eco-environment and therefore needs to be tackled by defining major causes to hinder or mitigate their impacts. The major driving forces of air pollution are either of local and/or regional origin. In addition, seasonal aerosols may be natural, such as dust particles transported from the western desert, or anthropogenic aerosols which are transported from industrial areas and smoke particles from seasonal biomass burning. Monitoring the optical properties of aerosols and their pattern in the atmosphere on a daily basis requires a robust source of information and professional analytical tools. This research explored the potential of using time series of Moderate Resolution Imaging Spectroradiometer (MODIS) and Aerosol Robotic Network (AERONET) data to comprehensively investigate the aerosol optical depth (AOD) and variability for the period 2012–2018 on a daily basis. The data show that spring, summer and autumn seasons experienced the highest anomaly originating from regional and national sources. The high AOD in spring associated with a low Ångström exponent (AE) indicates the presence of coarse particles which naturally originate from desert dust or sea spray. In contrast, the high AE in summer and autumn demonstrated the dominance of fine anthropogenic aerosols such as smoke particles from local biomass burning. The observation of a high number of fire incidents over Egypt in October and November 2018, during the months of rice crop harvesting, showed that these incidents contribute to the presence of autumn aerosols across the country. In-situ measurements of Particulate Matter (PM10) from local stations from an environmental based network as well as the AERONET AOD were used to validate the MODIS AOD, providing a high correlation coefficient of r = 0.73. Full article
(This article belongs to the Section Aerosols)
Show Figures

Figure 1

Open AccessArticle
Effects of Treated Manure Conditions on Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn Equipped with Semicontinuous Pit Recharge System in Summer
Atmosphere 2020, 11(7), 713; https://doi.org/10.3390/atmos11070713 - 03 Jul 2020
Viewed by 215
Abstract
Gaseous emissions from animal production systems affect the local and regional air quality. Proven farm-scale mitigation technologies are needed to lower these emissions and to provide management practices that are feasible and sustainable. In this research, we evaluate the performance of a unique [...] Read more.
Gaseous emissions from animal production systems affect the local and regional air quality. Proven farm-scale mitigation technologies are needed to lower these emissions and to provide management practices that are feasible and sustainable. In this research, we evaluate the performance of a unique approach that simultaneously mitigates emissions and improves air quality inside a barn equipped with a manure pit recharge system. Specifically, we tested the effects of summertime feeding rations (used by farmers to cope with animal heat stress) and manure management. To date, the pit recharge system has been proven to be effective in mitigating both ammonia (NH3; approximately 53%) and hydrogen sulfide (H2S; approximately 84%) emissions during mild climate conditions. However, its performance during the hot season with a high crude protein diet and high nitrogen loading into the pit manure recharge system is unknown. Therefore, we compared the emissions and indoor air quality of the rooms (240 pigs, ~80 kg each) equipped with a conventional slurry and pit recharge system. The main findings highlight the importance and impact of seasonal variation and diet and manure management practices. We observed 31% greater NH3 emissions from the pit recharge system (33.7 ± 1.4 g·head−1·day−1) compared with a conventional slurry system (25.9 ± 2.4 g·head−1·day−1). Additionally, the NH3 concentration inside the barn was higher (by 24%) in the pit recharge system compared with the control. On the other hand, H2S emissions were 55% lower in the pit recharge system (628 ± 47 mg·head−1·day−1) compared with a conventional slurry pit (1400 ± 132 mg·head−1·day−1). Additionally, the H2S concentration inside the barn was lower (by 54%) in the pit recharge system compared with the control. The characteristics of the pit recharge liquid (i.e., aerobically treated manure), such as the total nitrogen (TN) and ammonium N (NH4-N) contents, contributed to the higher NH3 emissions from the pit recharge system in summer. However, their influence on H2S emissions had a relatively low impact, i.e., emissions were still reduced, similarly as they were in mild climate conditions. Overall, it is necessary to consider a seasonal diet and manure management practices when evaluating emissions and indoor air quality. Further research on minimizing the seasonal nitrogen loading and optimizing pit recharge manure characteristics is warranted. Full article
(This article belongs to the collection Livestock Odor and Air Quality)
Show Figures

Graphical abstract

Open AccessArticle
Heatwaves in the Future Warmer Climate of South Africa
Atmosphere 2020, 11(7), 712; https://doi.org/10.3390/atmos11070712 - 03 Jul 2020
Viewed by 284
Abstract
Weather and climate extremes, such as heat waves (HWs), have become more frequent due to climate change, resulting in negative environmental and socioeconomic impacts in many regions of the world. The high vulnerability of South African society to the impacts of warm extreme [...] Read more.
Weather and climate extremes, such as heat waves (HWs), have become more frequent due to climate change, resulting in negative environmental and socioeconomic impacts in many regions of the world. The high vulnerability of South African society to the impacts of warm extreme temperatures makes the study of the effect of climate change on future HWs necessary across the country. We investigated the projected effect of climate change on future of South Africa with a focus on HWs using an ensemble of regional climate model downscalings obtained from the Conformal Cubic Atmospheric Model (CCAM) for the periods 2010–2039, 2040–2069, and 2070–2099, with 1983–2012 as the historical baseline. Simulations were performed under the Representative Concentration Pathway (RCP) 4.5 (moderate greenhouse gas (GHG) concentration) and 8.5 (high GHG concentration) greenhouse gas emission scenarios. We found that the 30-year period average maximum temperatures may rise by up to 6 °C across much of the interior of South Africa by 2070–2099 with respect to 1983–2012, under a high GHG concentration. Simulated HW thresholds for all ensemble members were similar and spatially consistent with observed HW thresholds. Under a high GHG concentration, short lasting HWs (average of 3–4 days) along the coastal areas are expected to increase in frequency in the future climate, however the coasts will continue to experience HWs of relatively shorter duration compared to the interior regions. HWs lasting for shorter duration are expected to be more frequent when compared to HWs of longer durations (over two weeks). The north-western part of South Africa is expected to have the most drastic increase in HWs occurrences across the country. Whilst the central interior is not projected to experience pronounced increases in HW frequency, HWs across this region are expected to last longer under future climate change. Consistent patterns of change are projected for HWs under moderate GHG concentrations, but the changes are smaller in amplitude. Increases in HW frequency and duration across South Africa may have significant impacts on human health, economic activities, and livelihoods in vulnerable communities. Full article
(This article belongs to the Special Issue Climate Events and Extreme Weather)
Show Figures

Figure 1

Open AccessArticle
The Impact of MJO, Kelvin, and Equatorial Rossby Waves on the Diurnal Cycle over the Maritime Continent
Atmosphere 2020, 11(7), 711; https://doi.org/10.3390/atmos11070711 - 03 Jul 2020
Viewed by 237
Abstract
The impacts of the Madden–Julian Oscillation (MJO), Kelvin waves, and Equatorial Rossby (ER) waves on the diurnal cycle of rainfall and types of deep convection over the Maritime Continent are investigated using rainfall from the Tropical Rainfall Measurement Mission Multisatellite Precipitation Analysis and [...] Read more.
The impacts of the Madden–Julian Oscillation (MJO), Kelvin waves, and Equatorial Rossby (ER) waves on the diurnal cycle of rainfall and types of deep convection over the Maritime Continent are investigated using rainfall from the Tropical Rainfall Measurement Mission Multisatellite Precipitation Analysis and Infrared Weather States (IR–WS) data from the International Satellite Cloud Climatology Project. In an absolute sense, the MJO produced its strongest modulations of rainfall and organized deep convection over the islands, when and where convection is already strongest. The MJO actually has a greater percentage modulation over the coasts and seas, but it does not affect weaker diurnal cycle there. Isolated deep convection was also more prevalent over land during the suppressed phase, while organized deep convection dominated the enhanced phase, consistent with past work. This study uniquely examined the effects of Kelvin and ER waves on rainfall, convection, and their diurnal cycles over the Maritime Continent. The modulation of convection by Kelvin waves closely mirrored that by the MJO, although the Kelvin wave convection continued farther into the decreasing phase. The signals for ER waves were also similar but less distinct. An improved understanding of how these waves interact with convection could lead to improved subseasonal forecast skill. Full article
(This article belongs to the Section Meteorology)
Show Figures

Figure 1

Open AccessReview
Covid-19 Airborne Transmission and Its Prevention: Waiting for Evidence or Applying the Precautionary Principle?
Atmosphere 2020, 11(7), 710; https://doi.org/10.3390/atmos11070710 - 03 Jul 2020
Viewed by 408
Abstract
Besides the predominant ways of transmission of SARS-CoV-2 (namely, contacts and large droplets) the airborne one is increasingly taken into consideration as a result of latest research findings. Nevertheless, this possibility has been already suggested by previous studies on other coronaviruses including SARS-CoV [...] Read more.
Besides the predominant ways of transmission of SARS-CoV-2 (namely, contacts and large droplets) the airborne one is increasingly taken into consideration as a result of latest research findings. Nevertheless, this possibility has been already suggested by previous studies on other coronaviruses including SARS-CoV and MERS-CoV. To describe the state of the art of coronaviruses and airborne transmission, a systematic review was carried out using the PRISMA methodology. Overall, 64 papers were selected and classified into three main groups: laboratory experiments (12 papers), air monitoring (22) and epidemiological and airflow model studies (30). The airborne transmission of SARS-CoV-2 is suggested by the studies of the three groups, but none has yet obtained complete evidence. The sampling and detection methods have not been validated, therefore monitoring results are affected by a possible underestimation. Then, epidemiological investigations only hypothesize the airborne transmission as a possible explanation for some illness cases, but without estimating its attributable risk. Nevertheless, while waiting for more evidence, it is urgent to base advice on preventive measures, such as the use of masks, safe distancing and air ventilation, on the precautionary principle. Full article
(This article belongs to the Special Issue Bioaerosol Exposure and Risk Assessment)
Show Figures

Figure 1

Open AccessEditorial
Preface: Ozone Evolution in the Past and Future
Atmosphere 2020, 11(7), 709; https://doi.org/10.3390/atmos11070709 - 03 Jul 2020
Viewed by 214
Abstract
The stratospheric ozone plays an important role in the protection of the biosphere from the dangerous ultraviolet radiation of the sun [...] Full article
(This article belongs to the Special Issue Ozone Evolution in the Past and Future)
Open AccessArticle
Air Quality Degradation by Mineral Dust over Beijing, Chengdu and Shanghai Chinese Megacities
Atmosphere 2020, 11(7), 708; https://doi.org/10.3390/atmos11070708 - 02 Jul 2020
Viewed by 230
Abstract
Air pollution in Chinese megacities has reached extremely hazardous levels, and human activities are responsible for the emission or production of large amounts of particulate matter (PM). In addition to PM from anthropogenic sources, natural phenomena, such as dust storms over Asian deserts, [...] Read more.
Air pollution in Chinese megacities has reached extremely hazardous levels, and human activities are responsible for the emission or production of large amounts of particulate matter (PM). In addition to PM from anthropogenic sources, natural phenomena, such as dust storms over Asian deserts, may also emit large amounts of PM, which lead episodically to poor air quality over Chinese megacities. In this paper, we quantify the degradation of air quality by dust over Beijing, Chengdu and Shanghai megacities using the three dimensions (3D) chemistry transport model CHIMERE, which simulates dust emission and transport online. In the first part of our work, we evaluate dust emissions using Moderate Resolution Imaging Spectroradiometer (MODIS) and Infrared Atmospheric Sounding Interferometer (IASI) satellite observations of aerosol optical depth, respectively, in the visible and the thermal infrared over source areas. PM simulations were also evaluated compared to surface monitoring stations. Then, mineral dust emissions and their impacts on particle composition of several Chinese megacities were analyzed. Dust emissions and transport over China were simulated during three years (2011, 2013 and 2015). Annual dust contributions to the PM 10 budget over Beijing, Chengdu and Shanghai were evaluated respectively as 6.6%, 9.5% and 9.3%. Dust outbreaks largely contribute to poor air quality events during springtime. Indeed it was found that dust significantly contribute for 22%, 52% and 43% of spring PM 10 events (for Beijing, Chengdu and Shanghai respectively). Full article
(This article belongs to the Special Issue Sources and Composition of Ambient Particulate Matter)
Open AccessArticle
Idealized Simulations of City-Storm Interactions in a Two-Dimensional Framework
Atmosphere 2020, 11(7), 707; https://doi.org/10.3390/atmos11070707 - 02 Jul 2020
Viewed by 190
Abstract
Numerous studies have identified spatial variability in convective parameters such as rainfall totals and lightning flashes in the vicinity of large urban areas, yet many questions remain regarding the storm-scale processes that are altered during interaction with a city as well as which [...] Read more.
Numerous studies have identified spatial variability in convective parameters such as rainfall totals and lightning flashes in the vicinity of large urban areas, yet many questions remain regarding the storm-scale processes that are altered during interaction with a city as well as which urban features are most responsible for storm modification. This study uses an idealized, two-dimensional cloud model to investigate structural and evolutionary changes in a squall line as it passes over a simplified representation of a large city. A parameter space exploration is done in which the parameters of the city—surface temperature and surface roughness length—are systemically increased relative to the region surrounding the idealized city. The resultant suite of simulations demonstrates that storm parameters such as vertical velocity, hydrometeor mass, upward mass flux, and buoyant accelerations are enhanced when the storm passes over the idealized city. No such enhancement occurs in the control simulation without an idealized city. Full article
Show Figures

Figure 1

Open AccessArticle
Importance Evaluation Based on Random Forest Algorithms: Insights into the Relationship between Negative Air Ions Variability and Environmental Factors in Urban Green Spaces
Atmosphere 2020, 11(7), 706; https://doi.org/10.3390/atmos11070706 - 02 Jul 2020
Viewed by 282
Abstract
Negative air ions (NAIs) exert positive effects on human health. Urban green spaces produce NAIs and perform valuable ecological functions; this phenomenon has attracted much attention. However, NAIs in urban green spaces are influenced by many factors, leading to extremely large variability in [...] Read more.
Negative air ions (NAIs) exert positive effects on human health. Urban green spaces produce NAIs and perform valuable ecological functions; this phenomenon has attracted much attention. However, NAIs in urban green spaces are influenced by many factors, leading to extremely large variability in their concentrations and complicating their measurement. Therefore, we collected observational data on NAI concentrations (NAICs), as well as on other environmental factors for one year in Shanghai City Park. We then used this data to construct an indicator of NAI variability (NAIV); we understand NAIV to be dependent upon NAIC, and study of the derivative can better reflect the driving force and dominant factors of the original function. Based on a preliminary investigation of correlation, and on a multiple linear regression analysis, we used a random forest algorithm to evaluate the influence of various factors that affect the variability of NAIs. The results show that “water factors,” whose main contribution is humidity, exert the most influence, followed by “phenology factors,” whose main contribution is temperature, and “particulate factors,” whose main contribution is PM2.5. High humidity, high temperature, and low PM2.5 concentration enrich NAI generation and extend their lifetimes, thus helping to maintain them within a relatively stable range. In this study, the main driving forces that govern NAI changes were shown to be humidity, temperature and particulate matter. Our results may help to deepen our understanding of NAI characteristics and applications in urban green spaces. Full article
(This article belongs to the Special Issue Challenges in Applied Human Biometeorology)
Show Figures

Graphical abstract

Open AccessArticle
Evaluation of Rainfall Forecasts by Three Mesoscale Models during the Mei-Yu Season of 2008 in Taiwan. Part III: Application of an Object-Oriented Verification Method
Atmosphere 2020, 11(7), 705; https://doi.org/10.3390/atmos11070705 - 02 Jul 2020
Viewed by 176
Abstract
In this study, the performances of Mei-yu (May–June) quantitative precipitation forecasts (QPFs) in Taiwan by three mesoscale models: the Cloud-Resolving Storm Simulator (CReSS), the Central Weather Bureau (CWB) Weather Research and Forecasting (WRF), and the CWB Non-hydrostatic Forecast System (NFS) are explored and [...] Read more.
In this study, the performances of Mei-yu (May–June) quantitative precipitation forecasts (QPFs) in Taiwan by three mesoscale models: the Cloud-Resolving Storm Simulator (CReSS), the Central Weather Bureau (CWB) Weather Research and Forecasting (WRF), and the CWB Non-hydrostatic Forecast System (NFS) are explored and compared using an newly-developed object-oriented verification method, with particular focus on the various properties or attributes of rainfall objects identified. Against a merged dataset from ~400 rain gauges in Taiwan and the Tropical Rainfall Measuring Mission (TRMM) data in the 2008 season, the object-based analysis is carried out to complement the subjective analysis in a parallel study. The Mei-yu QPF skill is seen to vary with different aspects of rainfall objects among the three models. The CReSS model has a total rainfall production closest to the observation but a large number of smaller objects, resulting in more frequent and concentrated rainfall. In contrast, both WRF and NFS tend to under-forecast the number of objects and total rainfall, but with a higher proportion of bigger objects. Location errors inferred from object centroid locations appear in all three models, as CReSS, NFS, and WRF exhibit a tendency to simulate objects slightly south, east, and northwest with respect to the observation. Most rainfall objects are aligned close to an E–W direction in CReSS, in best agreement with the observation, but many towards the NE–SW direction in both WRF and NFS. For each model, the objects are matched with the observed ones, and the results of the matched pairs are also discussed. Overall, though preliminarily, the CReSS model, with a finer grid size, emerges as best performing model for Mei-yu QPFs. Full article
(This article belongs to the Section Meteorology)
Show Figures

Figure 1

Open AccessCommunication
Climatology of Tropospheric Relative Humidity over the Korean Peninsula from Radiosonde and ECMWF Reanalysis
Atmosphere 2020, 11(7), 704; https://doi.org/10.3390/atmos11070704 - 02 Jul 2020
Viewed by 211
Abstract
Conventional radiosondes can be used to measure the relative humidity over liquid (RHL) by assuming a saturated vapor pressure over the liquid. However, this assumption results in significant errors with respect to measurements in the upper troposphere, where the effect of ice is [...] Read more.
Conventional radiosondes can be used to measure the relative humidity over liquid (RHL) by assuming a saturated vapor pressure over the liquid. However, this assumption results in significant errors with respect to measurements in the upper troposphere, where the effect of ice is dominant. Therefore, this study presents a novel method that considers the effects of ice to determine the relative humidity from radiosonde RHL data for the last 40 years (1979–2018) over the upper layers of the Korean peninsula. Even though the relative humidity obtained from the reanalysis data was significantly different from the radiosonde-based RHL, the difference was much reduced when relative humidity was calculated using the novel method proposed in this study. Such improvements in the estimated relative humidity could be attributed to the consideration of the ice effect at temperatures above freezing level. Additionally, the validity of the relative humidity estimated in this study was established based on a two-week case analysis of data from Boseong station. Furthermore, two peak relative humidity modes for the lower and upper layers were clearly identified in the mean climatology profiles, which indirectly suggested the absence of mid-level clouds around the 700-hPa level and 500-hPa level in winter and summer, respectively. This study is meaningful as it is the first study to determine the relative humidity distribution over the Korean peninsula using radiosonde observations. The scientific value obtained can potentially be expanded by applying the proposed method to other radiosonde observation networks, which are widely distributed worldwide. Full article
(This article belongs to the Section Climatology)
Show Figures

Figure 1

Open AccessArticle
Spatiotemporal Distribution of Major Aerosol Types over China Based on MODIS Products between 2008 and 2017
Atmosphere 2020, 11(7), 703; https://doi.org/10.3390/atmos11070703 - 01 Jul 2020
Viewed by 256
Abstract
Knowledge of aerosol-type distribution is critical to the evaluation of aerosol–climate effects. However, research on aerosol-type distribution covering all is limited. This study characterized the spatiotemporal distribution of major aerosol types over China by using MODerate resolution Imaging Spectroradiometer (MODIS) products from 2008 [...] Read more.
Knowledge of aerosol-type distribution is critical to the evaluation of aerosol–climate effects. However, research on aerosol-type distribution covering all is limited. This study characterized the spatiotemporal distribution of major aerosol types over China by using MODerate resolution Imaging Spectroradiometer (MODIS) products from 2008 to 2017. Two aerosol-type classification methods were combined to achieve this goal. One was for relatively high aerosol load (AOD ≥ 0.2) using aerosol optical depth (AOD) and aerosol relative optical depth (AROD) and the other was for low aerosol load (AOD < 0.2) using land use and population density information, which assumed that aerosols are closely related to local emissions. Results showed that the dominant aerosol-type distribution has a distinct spatial and temporal pattern. In western China, background aerosols (mainly dust/desert dust and continent aerosol) dominate with a combined occurrence ratio over 70% and they have slight variations on seasonal scale. While in eastern China, the dominant aerosols show strong seasonal variations. Spatially, mixed aerosols dominate most parts of eastern China in spring due to the influence of long-range transported dust from Taklamakan and Gobi desert and urban/industry aerosols take place in summer due to strong photochemical reactions. Temporally, mixed and urban/industry aerosols co-dominate eastern China. Full article
(This article belongs to the Section Aerosols)
Show Figures

Figure 1

Open AccessArticle
Performance of Forecasts of Hurricanes with and without Upper-Level Troughs over the Mid-Latitudes
Atmosphere 2020, 11(7), 702; https://doi.org/10.3390/atmos11070702 - 01 Jul 2020
Viewed by 274
Abstract
We investigated the accuracy of operational medium-range ensemble forecasts for 29 Atlantic hurricanes between 2007 and 2019. Upper-level troughs with strong wind promoted northward movement of hurricanes over the mid-latitudes. For hurricanes with upper-level troughs, relatively large errors in the prediction of troughs [...] Read more.
We investigated the accuracy of operational medium-range ensemble forecasts for 29 Atlantic hurricanes between 2007 and 2019. Upper-level troughs with strong wind promoted northward movement of hurricanes over the mid-latitudes. For hurricanes with upper-level troughs, relatively large errors in the prediction of troughs result in large ensemble spreads, which result in failure to forecast hurricane track. In contrast, for hurricanes without upper-level troughs, mean central position errors are relatively small in all operational forecasts because of the absence of upper-level strong wind around troughs over the mid-latitudes. Hurricane Irma in September 2017 was accompanied by upper-level strong wind around a trough; errors and ensemble spreads for the predicted upper-level trough are small, contributing to smaller errors and small ensemble spreads in the predicted tracks of Irma. Our observing system experiment reveals that inclusion of additional Arctic radiosonde observation data obtained from research vessel Mirai in 2017 improves error and ensemble spread in upper-level trough with strong wind at initial time for forecast, increasing the accuracy of the forecast of the track of Irma in 2017. Full article
(This article belongs to the Special Issue Modeling and Data Assimilation for Tropical Cyclone Forecasts)
Show Figures

Figure 1

Open AccessArticle
A Data-Driven Approach for Winter Precipitation Classification Using Weather Radar and NWP Data
Atmosphere 2020, 11(7), 701; https://doi.org/10.3390/atmos11070701 - 01 Jul 2020
Viewed by 212
Abstract
This study describes a framework that provides qualitative weather information on winter precipitation types using a data-driven approach. The framework incorporates the data retrieved from weather radars and the numerical weather prediction (NWP) model to account for relevant precipitation microphysics. To enable multimodel-based [...] Read more.
This study describes a framework that provides qualitative weather information on winter precipitation types using a data-driven approach. The framework incorporates the data retrieved from weather radars and the numerical weather prediction (NWP) model to account for relevant precipitation microphysics. To enable multimodel-based ensemble classification, we selected six supervised machine learning models: k-nearest neighbors, logistic regression, support vector machine, decision tree, random forest, and multi-layer perceptron. Our model training and cross-validation results based on Monte Carlo Simulation (MCS) showed that all the models performed better than our baseline method, which applies two thresholds (surface temperature and atmospheric layer thickness) for binary classification (i.e., rain/snow). Among all six models, random forest presented the best classification results for the basic classes (rain, freezing rain, and snow) and the further refinement of the snow classes (light, moderate, and heavy). Our model evaluation, which uses an independent dataset not associated with model development and learning, led to classification performance consistent with that from the MCS analysis. Based on the visual inspection of the classification maps generated for an individual radar domain, we confirmed the improved classification capability of the developed models (e.g., random forest) compared to the baseline one in representing both spatial variability and continuity. Full article
(This article belongs to the Special Issue Radar Hydrology and QPE Uncertainties)
Show Figures

Figure 1

Open AccessArticle
Risk Mapping for the Sustainable Protection of Cultural Heritage in Extreme Changing Environments
Atmosphere 2020, 11(7), 700; https://doi.org/10.3390/atmos11070700 - 01 Jul 2020
Viewed by 192
Abstract
Cultural heritage is widely recognized to be at risk due to the impact of climate change and associated hazards, such as events of heavy rain, flooding, and drought. User-driven solutions are urgently required for sustainable management and protection of monumental complexes and related [...] Read more.
Cultural heritage is widely recognized to be at risk due to the impact of climate change and associated hazards, such as events of heavy rain, flooding, and drought. User-driven solutions are urgently required for sustainable management and protection of monumental complexes and related collections exposed to changes of extreme climate. With this purpose, maps of risk-prone areas in Europe and in the Mediterranean Basin have been produced by an accurate selection and analysis of climate variables (daily minimum and maximum temperature - Tn and Tx, daily cumulated precipitation - RR) and climate-extreme indices (R20mm, R95pTOT, Rx5 day, CCD, Tx90p) defined by Expert Team on Climate Change Detection Indices (ETCCDI). Maps are available to users via an interactive Web GIS (Geographic Information System) tool, which provides evaluations based on historical observations (high-resolution gridded data set of daily climate over Europe - E-OBS, 25 km) and climate projections (regional climate models - RCM, ~12 km) for the near and far future, under Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. The tool aims to support public authorities and private organizations in the decision making process to safeguard at-risk cultural heritage. In this paper, maps of risk-prone areas of heavy rain in Central Europe (by using R20mm index) are presented and discussed as example of the outputs achievable by using the Web GIS tool. The results show that major future variations are always foreseen for the 30-year period 2071–2100 under the pessimistic scenario (RCP 8.5). In general, the coastal area of the Adriatic Sea, the Northern Italy, and the Alps are foreseen to experience the highest variations in Central Europe. Full article
(This article belongs to the Special Issue Assessing the Impact of Climate Change on Urban Cultural Heritage)
Show Figures

Graphical abstract

Open AccessArticle
Effect of Model Resolution on Intense and Extreme Precipitationinthe Mediterranean Region
Atmosphere 2020, 11(7), 699; https://doi.org/10.3390/atmos11070699 - 01 Jul 2020
Viewed by 176
Abstract
This study explores the role of model resolution on the simulation of precipitation and on the estimate of its future change in the Mediterranean region. It compares the results of two regional climate models (RCMs, with two different horizontal grid resolutions, 0.44 and [...] Read more.
This study explores the role of model resolution on the simulation of precipitation and on the estimate of its future change in the Mediterranean region. It compares the results of two regional climate models (RCMs, with two different horizontal grid resolutions, 0.44 and 0.11 degs, covering the whole Mediterranean region) and of the global climate model (GCM, 0.75 degs) that has provided the boundary conditions for them. The regional climate models include an interactive oceanic component with a resolution of 1/16 degs. The period 1960–2100 and the representative concentration pathways RCP4.5 and RCP8.5 are considered. The results show that, in the present climate, increasing resolution increases total precipitation and its extremes over steep orography, while it has the opposite effect over flat areas and the sea. Considering climate change, in all simulations, total precipitation will decrease over most of the considered domain except at the northern boundary, where it will increase. Extreme precipitation will increase over most of the northern Mediterranean region and decrease over the sea and some southern areas. Further, the overall probability of precipitation (frequency of wet days) significantly decreases over most of the region, but wet days will be characterized with precipitation intensity higher than the present. Our analysis shows that: (1) these projected changes are robust with respect to the considered range of model resolution; (2) increasing the resolution (within the considered resolution range) decreases the magnitude of these climate change effects. However, it is likely that resolution plays a less important role than other factors, such as the different physics of regional and global climate models. It remains to be investigated whether further increasing the resolution (and reaching the scale explicitly permitting convection) would change this conclusion. Full article
Show Figures

Figure 1

Previous Issue
Back to TopTop