Satellite Data Potentialities in Solid Waste Landfill Monitoring: Review and Case Studies.

Remote sensing can represent an important instrument for monitoring landfills and their evolution over time. In general, remote sensing can offer a global and rapid view of the Earth's surface. Thanks to a wide variety of heterogeneous sensors, it can provide high-level information, making it a useful technology for many applications. The main purpose of this paper is to provide a review of relevant methods based on remote sensing for landfill identification and monitoring. The methods found in the literature make use of measurements acquired from both multi-spectral and radar sensors and exploit vegetation indexes, land surface temperature, and backscatter information, either separately or in combination. Moreover, additional information can be provided by atmospheric sounders able to detect gas emissions (e.g., methane) and hyperspectral sensors. In order to provide a comprehensive overview of the full potential of Earth observation data for landfill monitoring, this article also provides applications of the main procedures presented to selected test sites. These applications highlight the potentialities of satellite-borne sensors for improving the detection and delimitation of landfills and enhancing the evaluation of waste disposal effects on environmental health. The results revealed that a single-sensor-based analysis can provide significant information on the landfill evolution. However, a data fusion approach that incorporates data acquired from heterogeneous sensors, including visible/near infrared, thermal infrared, and synthetic aperture radar (SAR), can result in a more effective instrument to fully support the monitoring of landfills and their effect on the surrounding area. In particular, the results show that a synergistic use of multispectral indexes, land surface temperature, and the backscatter coefficient retrieved from SAR sensors can improve the sensitivity to changes in the spatial geometry of the considered site.

Particulate matter and COVID-19 excess deaths: Decomposing long-term exposure and short-term effects.

We investigate the time-varying effect of particulate matter (PM) on COVID-19 deaths in Italian municipalities. We find that the lagged moving averages of PM2.5 and PM10 are significantly related to higher excess deceases during the first wave of the disease, after controlling, among other factors, for time-varying mobility, regional and municipality fixed effects, the nonlinear contagion trend, and lockdown effects. Our findings are confirmed after accounting for potential endogeneity, heterogeneous pandemic dynamics, and spatial correlation through pooled and fixed-effect instrumental variable estimates using municipal and provincial data. In addition, we decompose the overall PM effect and find that both pre-COVID long-term exposure and short-term variation during the pandemic matter. In terms of magnitude, we observe that a 1 µg/m3 increase in PM2.5 can lead to up to 20% more deaths in Italian municipalities, which is equivalent to a 5.9% increase in mortality rate.

Insights into the Porretta Terme (northern Apennines, Italy) hydrothermal system revealed by geochemical data on presently discharging thermal waters and paleofluids.

This study focuses on the geochemical features of the presently discharging thermal and cold springs and on paleofluids from the upstream portion of the Reno river basin (Alto Reno; central-northern Italy). The aim is investigating the primary sources of the modern and fossil fluids and the interactions between deep and shallow aquifers. Paleofluids are from fluid inclusions hosted within euhedral and hopper quartz crystals and consist of a two-phase, liquid-vapor aqueous fluid and a unary CH4 fluid. The aqueous inclusions have constant phase ratios and a calculated salinity of ~ 1.5 wt% NaCleq. They homogenize by bubble disappearance at 100-200 °C, whereas the estimated entrapment depth is ~ 3-5.5 km. The paleofluids likely represent the vestiges of the deep and hot, CH4-rich, Na+-Cl- fluids produced by the interaction between meteoric waters and Triassic and Miocene formations. The modern Na+-Cl-(HCO3-) thermal waters originate from meteoric waters infiltrating SW of the study area, at elevation > 800 m a.s.l., circulating within both the Triassic evaporites and the overlying Miocene turbiditic formations, where salt dissolution/precipitation, sulfate reduction, and production of thermogenic CH4 occur. The equilibrium temperature of the deep fluid source is ~ 170 °C, corresponding to > 5 km depth. Cold springs are Ca2+-HCO3- type and show low amounts of biogenic CO2 and CH4 with no inputs of deep-originated fluids excepting in the immediate surroundings of the thermal area, confirming the lack of significant hydraulic connection between shallow and deep aquifers. We propose a genetic link between the quartz-hosted paleofluid and the thermal waters present in the area.

Air quality and COVID-19 adverse outcomes: Divergent views and experimental findings.

BACKGROUND: The questioned link between air pollution and coronavirus disease 2019 (COVID-19) spreading or related mortality represents a hot topic that has immediately been regarded in the light of divergent views. A first "school of thought" advocates that what matters are only standard epidemiological variables (i.e. frequency of interactions in proportion of the viral charge). A second school of thought argues that co-factors such as quality of air play an important role too. METHODS: We analyzed available literature concerning the link between air quality, as measured by different pollutants and a number of COVID-19 outcomes, such as number of positive cases, deaths, and excess mortality rates. We reviewed several studies conducted worldwide and discussing many different methodological approaches aimed at investigating causality associations. RESULTS: Our paper reviewed the most recent empirical researches documenting the existence of a huge evidence produced worldwide concerning the role played by air pollution on health in general and on COVID-19 outcomes in particular. These results support both research hypotheses, i.e. long-term exposure effects and short-term consequences (including the hypothesis of particulate matter acting as viral "carrier") according to the two schools of thought, respectively. CONCLUSIONS: The link between air pollution and COVID-19 outcomes is strong and robust as resulting from many different research methodologies. Policy implications should be drawn from a "rational" assessment of these findings as "not taking any action" represents an action itself.