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ABSTRACTUsing a high-resolution, 1.33 km by 1.33 km coupled Weather Research and Forecasting-Community Multi-scale Air Quality Model (WRF-CMAQ), we quantify the impact of emissions of nitrogen oxides (NOx) from high energy demand day (HEDD) electricity generating units (EGU) and onroad vehicles on ambient ozone air quality in the Long Island Sound Tropospheric Ozone Study (LISTOS) region covering New York City (NYC); Long Island, NY; coastal Connecticut; and neighboring areas. We test sensitivity scenarios to quantify HEDD EGU NOx contributions to ozone: (1) zero out HEDD EGU emissions, (2) dispatch HEDD EGUs starting with the lowest NOx emitting units first, (3) reduce onroad emissions by 90%, (4) combine zero out HEDD EGU emissions and reducing onroad emissions by 90%, and (5) dispatch HEDD EGUs starting with the lowest emitting units coupled with a reduction in onroad emissions by 90%. Results determine that HEDD EGUs lead to highly localized impacts on ambient concentrations of ozone while onroad emission reductions lead to large-scale regional concentration impacts. Further, reducing onroad emissions by 90% leads to spatially smaller VOC-limited regions and spatially larger transitional and NOX-limited regions around NYC. Despite the limited scale at which the EGU emission reductions occur, modifying HEDD EGU NOXemissions still provides substantial benefits in reducing ozone concentrations in the region, particularly at elevated ozone concentrations above 70 ppb.Implications:High-resolution coupled meteorology-chemistry modeling was used to quantify the impacts of high energy demand day (HEDD) electricity generating units (EGUs) and onroad transportation emissions changes on ozone air quality in the LISTOS region. Despite being highly localized and variable, HEDD EGUs NOXemissions sensitivity tests led to quantifiable changes in ozone. Further, reducing onroad emissions by 90% produced large decreases in ozone concentrations and led to a more NOX-sensitive ozone photochemical regime. With a transition to greater NOX-sensitivity, urban NOX-titration weakens and ozone is more likely to decline with the removal of additional NOXfrom sources like HEDD EGUs.

As cities strive for ambitious increases in tree canopy cover and reductions in anthropogenic volatile organic compound (AVOC) emissions, accurate assessments of the impacts of biogenic VOCs (BVOCs) on air quality become more important. In this study, we aim to quantify the impact of future urban greening on ozone production. BVOC emissions in dense urban areas are often coarsely represented in regional models. We set up a high-resolution (30 m) MEGAN (The Model of Emissions of Gases and Aerosols from Nature version 3.2) to estimate summertime biogenic isoprene emissions in the New York City metro area (NYC-MEGAN). Coupling an observation-constrained box model with NYC-MEGAN isoprene emissions successfully reproduced the observed isoprene concentrations in the city core. We then estimated future isoprene emissions from likely urban greening scenarios and evaluated the potential impact on future ozone production. NYC-MEGAN predicts up to twice as much isoprene emissions in NYC as the coarse-resolution (1.33 km) Biogenic Emission Inventory System version 3.61 (BEIS) on hot summer days. We find that BVOCs drive ozone production on hot summer days, even in the city core, despite large AVOC emissions. If high isoprene emitting species (e.g., oak trees) are planted, future isoprene emissions could increase by 1.4–2.2 times in the city core, which would result in 8–19 ppbv increases in peak ozone on ozone exceedance days with current NOxconcentrations. We recommend planting non- or low-isoprene emitting trees in cities with high NOxconcentrations to avoid an increase in the frequency and severity of future ozone exceedance events.

Administrative Law Judge (ALJ) David Shaw of the International Trade Commission (ITC or Commission) recently issued his final initial determination (ID) in Certain Portable Electronic Devices and Components Thereof. (1) [...]

Understanding the local-scale spatial and temporal variability of ozone formation is crucial for effective mitigation. We combine tropospheric vertical column densities (VCDTrop) of formaldehyde (HCHO) and nitrogen dioxide (NO2), referred to as HCHO-VCDTropand NO2-VCDTrop, retrieved from airborne remote sensing and the TROPOspheric Monitoring Instrument (TROPOMI) with ground-based measurements to investigate changes in ozone precursors and the inferred chemical production regime on high-ozone days in May–August 2018 over two Northeast urban domains. Over New York City (NYC) and Baltimore/Washington D.C. (BAL/DC), HCHO-VCDTropincreases across the domain, but higher NO2-VCDTropoccurs mainly in urban centers on ozone exceedance days (when maximum daily 8 h average (MDA8) ozone exceeds 70 ppb at any monitor in the region). The ratio of HCHO-VCDTropto NO2-VCDTrop, proposed as an indicator of the sensitivity of local surface ozone production rates to its precursors, generally increases on ozone exceedance days, implying a transition toward a more NOx-sensitive ozone production regime that should lead to higher efficacy of NOxcontrols on the highest ozone days in NYC and BAL/DC. Warmer temperatures and enhanced influence from emissions in the local boundary layer on the high-ozone days are accompanied by slower wind speeds in BAL/DC but stronger, southwesterly winds in NYC.

Diverse anthropogenic activities are changing our natural environment, with important implications for human health. Successfully managing their impacts requires an understanding of the compounding hazards resulting from multi-faceted environmental changes. Here, we propose a human-environment systems lens comprising public health, climate, air quality, and agricultural land-use land management to characterize the combined health risks of anthropogenic environmental changes. Interactions within this system can amplify, diminish, or generate additional hazards associated with changes in any individual element. Using South Asia as an example—where rapid industrialization and the Green Revolution aided economic development and food production but inadvertently compromised multiple human health dimensions—we synthesize the influence of human-environment system interactions on environment-sensitive health outcomes. We further demonstrate the utility of this lens for evaluating the health outcomes of existing and planned regional policies and interventions to identify unintended negative consequences and solutions that realize co-benefits and minimize trade-offs.

The article discusess the history of First Amendment to the U.S. Constitution. Topics discussed include philosophical justification and a practical means of freedoms in the First Amendment; book "Areopagitica" by John Milton on right to freedom of speech and expression; and protection to civil rights under the same.

Ambient fine particulate matter (PM2.5) concentrations in India frequently exceed 100 μg/m3during fall and winter pollution episodes. We use the GEOS‐Chem chemical transport model with the TwO‐Moment Aerosol Sectional microphysics scheme with 15 size bins (TOMAS15) to assess PM2.5composition and impacts on radiation and cloud condensation nuclei (CCN) during pollution episodes as compared to the seasonal (October‐December) average. We conduct high resolution (0.25° × 0.3125°) nested‐domain simulations over India for short‐duration, high‐PM2.5episodes in the fall of 2015 and 2017. The simulations capture the magnitude and spatial patterns of pollution episodes measured by surface monitors (r2PM2.5= 0.69) although aerosol optical depth is underestimated. During the episodes, near‐surface organic matter (OM), black carbon (BC), and secondary inorganic aerosol concentrations increase from seasonal averages by up to 36, 7, and 7 μg/m3, respectively. Episodic aerosol increases enhance cooling by lowering the top‐of‐atmosphere clear‐sky direct radiative effect (DRETOA) during the 2015 episode (−6 W/m2), with a smaller impact during the 2017 episode (−1 W/m2). Differences in DRETOAreflect larger increases in scattering aerosols in the column during the 2015 episode (+17 mg/m2) than in 2017 (+13 mg/m2), while absorbing aerosol column enhancements are smaller (+3 mg/m2) in both years. Changes in shortwave radiation at the surface (SWsfc) are spatially similar to DRETOAand mostly negative during both episodes. CCN enhancements (0.2% supersaturation) during these episodes occur across the western Indo‐Gangetic Plain, coincident with higher PM2.5concentrations. Changes in DRETOA, SWsfc, and CCN during high‐PM2.5episodes may have implications for crops, the hydrologic cycle, and surface temperature. We establish a new high‐resolution India domain nested within a global chemistry model with an option for detailed aerosol microphysicsPM2.5pollution episodes over India vary spatially but are commonly dominated by carbonaceous aerosolsIncreased scattering by aerosols reduces top‐of‐atmosphere direct radiative effect and surface shortwave radiation, enhancing cooling We establish a new high‐resolution India domain nested within a global chemistry model with an option for detailed aerosol microphysics PM2.5pollution episodes over India vary spatially but are commonly dominated by carbonaceous aerosols Increased scattering by aerosols reduces top‐of‐atmosphere direct radiative effect and surface shortwave radiation, enhancing cooling

Aneuploidy is found in most solid tumours, but it remains unclear whether it is the cause or the consequence of tumorigenesis. Using Plk4 overexpression (PLK4OE) during epidermal development, we assess the impact of centrosome amplification and aneuploidy on skin development and tumorigenesis. PLK4OE in the developing epidermis induced centrosome amplification and multipolar divisions, leading to p53 stabilization and apoptosis of epidermal progenitors. The resulting delayed epidermal stratification led to skin barrier defects. Plk4 transgene expression was shut down postnatally in the surviving mice and PLK4OE mice never developed skin tumours. Concomitant PLK4OE and p53 deletion (PLK4OE/p53cKO) rescued the differentiation defects, but did not prevent the apoptosis of PLK4OE cells. Remarkably, the short-term presence of cells with supernumerary centrosomes in PLK4OE/p53cKO mice was sufficient to generate aneuploidy in the adult epidermis and triggered spontaneous skin cancers with complete penetrance. These results reveal that aneuploidy induced by transient centrosome amplification can accelerate tumorigenesis in p53-deficient cells.

Bandwidth has been mentioned by the media a lot recently, but just what is it and what can it do? Bandwidth often is referred to as the speed at which [...]