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Sea surface temperature (SST) is characterized by abundant warm and cold structures that influence the overlying atmospheric boundary layer dynamics through two different mechanisms. First, turbulence and large eddies in the lower troposphere are affected by atmospheric stability, which can be modified by local SST, resulting in enhanced vertical mixing and larger surface winds over warmer waters. Second, the thermodynamic adjustment of air density to the underlying SST structures and the subsequent changes in atmospheric pressure drive secondary circulations. This paper aims to disentangle the effects of these processes and explore the environmental conditions that favor them. Two main environmental variables are considered: the large-scale air–sea temperature difference (proxy for stability) and wind speed. Using 5 years of daily reanalyses data, we investigate the 10-m wind response to SST structures. Based on linear regression between wind divergence and SST derivatives, we show that both mechanisms operate over a large spectrum of conditions. Ten-meter wind divergence is strongly impacted by the local SST via its effect on vertical mixing for midwind regimes in slightly unstable to near-neutral conditions, whereas the secondary circulation is important in two distinct regimes: low wind speed with a slightly unstable air column and high background wind speed with a very unstable air column. The first regime is explained by the prolonged Lagrangian time that the air parcel stays over an SST structure while the second one is related to strong heat fluxes at the air–sea interface, which greatly modify the marine atmospheric boundary layer properties. Location and frequency of the environmentally favorable conditions are discussed, as well as the response in low-cloud cover and rainfall. Significance Statement The main objective of this study is to explore the wind response to thermal structures at the sea surface under different environmental conditions using the latest atmospheric reanalysis. Recent literature suggests that fine-scale air–sea interactions affect a large spectrum of atmospheric dynamics, from seasonal to weather-type regimes. It is thus important to characterize the atmospheric response to ocean surface variability. Our findings describe the environmental conditions for which the two main physical processes through which the atmosphere responds to sea surface temperature structures are active the most and can guide the development of high-resolution observing missions and campaigns in specific geographical locations and seasons to retrieve data that can be used to improve parameterization in models.

Wind Induced Surface Heat Exchange (WISHE) mechanism is considered very important for tropical cyclone intensification in a large part of the scientific literature([1], [2], [3] ): heat flux from the ocean increase with increasing wind speed, building up a positive feedback on the intensification.Simple WISHE-based models of tropical intensification predict that tropical cyclones intensify up to a steady state at the Potential Intensity (PI), obtained from the balance of heat supply rate from the ocean and dissipation rate in the boundary layer and dependent on boundary conditions only ([1]). The main problem of such models is the fact that they typically drastically simplify the convective motion within the cyclone, assuming a troposphere neutral to moist convection. ([4]).In our work we tested these predictions in idealized numerical experiments performed using the non-hydrostatic, high-resolution model System for Atmospheric Modelling (SAM). The results showed a significantly different intensity evolution, with the cyclone undergoing a oscillation in surface wind speed with peak intensity significantly lower than the PI. This intensity evolution was related to that of the environmental conditions along the whole air column: convective heating exports latent and sensible heat in the middle-upper troposphere, increasing environmental air buoyancy and so reducing CAPE. Radiative heating from the clouds further stabilizes the upper troposphere, weakening convection and thus cyclone intensity. After the intensity decay phase the upper level air surrounding the cyclone cools down through radiation emission: entrainment of cold air by the cyclone itself rebuilts CAPE and triggers a new intensification. Despite this work showed some limits in the predictivity of WISHE theory, WISHE feedback itself was proved to be fundamental for tropical cyclone intensification with a sensitivity numerical experiment. [1] K. Emanuel et al., “Tropical cyclones,” Annual review of earth and planetary sciences, vol. 31,no. 1, pp. 75–104, 2003[2] K. A. Emanuel, “An Air-Sea Interaction Theory for Tropical Cyclones. Part I: Steady-StateMaintenance.,” Journal of Atmospheric Sciences, vol. 43, pp. 585–605, Mar. 1986.[3] C. J. Muller and D. M. Romps, “Acceleration of tropical cyclogenesis by self-aggregationfeedbacks,” Proceedings of the National Academy of Sciences, vol. 115, no. 12, pp. 2930–2935, 2018.[4] K. A. Emanuel, “The behavior of a simple hurricane model using a convective scheme basedon subcloud-layer entropy equilibrium,” Journal of Atmospheric Sciences, vol. 52, no. 22,pp. 3960 – 3968, 1995.

Microalgae are photosynthetic microorganisms that can employ some inorganic pollutant compounds as nutrients, for example nitrates and phosphates. Traditional wastewater treatment comprises oxidation ponds in which the Activated Sludge performs the oxidation of the organic matter. Microalgae may be well applied in these processes. In this work, we tested the potential of remediation of a mixture of a local microalga, Chlorella sp. Pozzillo, and activated sludge and compared it to controls of only microalga and only activated sludge. We found that the mixture of bacteria and microalgae leads to an improvement in nitrogen removal up to the 83,68%, while phosphorous removal is improved when the autochthonous microalgae are used alone. The abatement of the Chemical Oxygen Demand was of 59,17% when using the microalgae and activated sludge consortium, while it was higher (-76,67%±0) when using the only activated sludge. The biomass was also analysed for its content in lipids and carbohydrates. This information may be useful to assess the best industrial application for the biomass obtained from civil wastewaters remediation process, in accordance with principles of circular economy and waste-to-resources view.

The B/Ca ratio in calcareous marine species is informative of past seawater CO32- concentrations, but scarce data exist on B/Ca in coralline algae. Recent studies suggest influences of temperature and growth rates on B/Ca, the effect of which could be critical for the reconstructions of surface ocean pH and atmospheric pCO2. In this paper, we present the first laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of Mg, Sr, Li, and B in the coralline alga Lithothamnion corallioides collected from different geographic settings and depths across the Mediterranean Sea and in the Atlantic Ocean. We produced the first data on putative temperature proxies (Mg/Ca, Li/Ca, Sr/Ca, Mg/Li) and B/Ca in a coralline algal species grown in different basins from across the photic zone (12, 40, 45, and 66 m depth). We tested the B/Ca correlation with temperature proxies and growth rates in order to evaluate their possible effect on B incorporation. Our results suggested a growth rate influence on B/Ca, which was evident in the sample with the lowest growth rate of 0.10 mm yr−1 (Pontian Isl., Italy; 66 m depth) and in Elba (Italy; 45 m depth), where the algal growth rate was the highest (0.14 mm yr−1). At these two sites, the measured B/Ca was the lowest at 462.8 ± 49.2 µmol mol−1 and the highest at 757.7 ± 75.5 µmol mol−1, respectively. A positive correlation between B/Ca and temperature proxies was found only in the shallowest sample from Morlaix (Atlantic coast of France; 12 m depth), where the amplitude of temperature variation (ΔT) was the highest (8.9 ∘C). Still, fluctuations in B/Ca did not mirror yearly seasonal temperature oscillations as for Mg/Ca, Li/Ca, and Sr/Ca. We concluded that growth rates, triggered by the different ΔT and light availability across depth, affect the B incorporation in L. corallioides.

Background: With the emergence of whole slide imaging (WSI) and widespread access to high-speed Internet, pathology labs are now poised to implement digital pathology as a way to access diagnostic pathology expertise. This paper describes a collaborative partnership between a high-volume reference diagnostic laboratory (Labcorp) and an academic pathology department (Mount Sinai Hospital) in the transition from a traditional glass slide service to a digital platform. Using the standard framework of implementation science, we evaluate the consistency and quality of the Philips IntelliSite Pathology Solution (PIPS) in delivering save and efficient diagnostic services. Materials and Methods: Digital and glass slide diagnoses of all consult cases were documented over a 12-month period. The Proctor guideline was used to quantitatively and qualitatively measure (e.g., focus group studies, field notes, and administrative data) implementation success. Lean techniques (e.g., value stream mapping) were applied to measure changes in efficiency with the transition to a digital platform. Results: Our study supports the acceptability, high adoption, appropriateness, feasibility, fidelity, and sustainability of the digital pathology platform. The digital portal also improved the quality of patient care by increasing efficiency, effectiveness, safety, and timeliness. The intraobserver concordance rate was 100%. The digital transition resulted in a reduction in turnaround time from 86 h to an average 35 min and a 20-fold increase in efficiency of the consultation process. Conclusion: As the pathology community contemplates digital pathology as a transformational tool in providing broad access to diagnostic expertise across time and space, our study provides an implementation strategy along with evidence that the digital platform is safe, effective, and efficient.

We describe the main structure and outcomes of the new probabilistic seismic hazard model for Italy, MPS19 [Modello di Pericolosità Sismica, 2019]. Besides to outline the probabilistic framework adopted, the multitude of new data that have been made available after the preparation of the previous MPS04, and the set of earthquake rate and ground motion models used, we give particular emphasis to the main novelties of the modeling and the MPS19 outcomes. Specifically, we (i) introduce a novel approach to estimate and to visualize the epistemic uncertainty over the whole country; (ii) assign weights to each model components (earthquake rate and ground motion models) according to a quantitative testing phase and structured experts’ elicitation sessions; (iii) test (retrospectively) the MPS19 outcomes with the horizontal peak ground acceleration observed in the last decades, and the macroseismic intensities of the last centuries; (iv) introduce a pioneering approach to build MPS19_cluster, which accounts for the effect of earthquakes that have been removed by declustering. Finally, to make the interpretation of MPS19 outcomes easier for a wide range of possible stakeholders, we represent the final result also in terms of probability to exceed 0.15 g in 50 years., peer-reviewed

Thermal structures at the sea surface are known to affect the overlying atmospheric dynamics over various spatio-temporal scales, from hourly and sub-kilometric to annual and O(1000 km). The releva...

The knowledge of tropospheric water vapor distribution can significantly improve the accuracy of Numerical Weather Prediction (NWP) models. The present work proposes an automatic and fast procedure for generating reliable water vapor products from the synergic use of Sentinel-1 Synthetic Aperture Radar (SAR) imagery and Global Navigation Satellite System (GNSS) observations. Moreover, a compression method able to drastically reduce, without significant accuracy loss, the water vapor dataset dimension has been implemented to facilitate the sharing through cloud services. The activities have been carried in the EU H2020 TWIGA project framework, aimed at providing water vapor maps at Technology Readiness Level 7.

Using 25years of ERA5 reanalysis data, this study shows that wind divergence is partially driven by small-scale sea surface temperature (SST) patterns via their effect on the boundary layer stability. Moreover, strong warm-to-cold fronts (the upper quartile) are associated with a mean increase of cloud cover of 10%±5% and a mean increase in the probability of a rain event of 15%±6%, with respect to the average values. The cloud and rainfall dependence on SST fronts is more pronounced in Fall, probably due to the stronger SST gradients present at the end of the summer season.

Numerical models are operationally used for weather forecasting activities to reduce the risks of several hydro-meteorological disasters. The overarching goal of this work is to evaluate the Weather Research and Forecasting (WRF) model predictive capabilities over the Italian national territory in the year 2018, in two specific cloud resolving configurations. The validation is carried out with a fuzzy logic approach, by comparing the precipitation predicted by the WRF model, and the precipitation observed by the national network. The fuzzy logic technique, by considering different intensity thresholds, allows to identify the reliable spatial scales of the forecasts. The same approach is applied to evaluate the performances of COSMO-2I model, a state-of-the-art numerical model configuration used for operational activities. For the entire year, except for summer, the model predictive capabilities are high, with useful forecasts for structures of medium intensities down to O(10 km) length scales. In summer the skills decrease mainly because of localization errors. The work aims to provide a robust evaluation of the forecast performances of another convection permitting operational meteorological models currently available in Italy.

Sea Surface Temperature (SST) is known to affect the marine atmospheric boundary layer (MABL) at scales smaller than O(1000 km) via different mechanisms. In particular, the oceanic thermal forcing induces modification in the wind speed, its divergence and its curl by the action of the Downward Momentum Mixing (DMM) mechanism and the Pressure Adjustment (PA) one. By analyzing 25 years of observations of surface wind speed and SST in the Mediterranean, it is found that the probability of observing surface wind convergence is significantly higher over a thermal oceanic front crossed from the warm to the cold side, in agreement with the DMM mechanism. Physically, this is due to a deceleration of the surface wind over the cold side of the SST front because of the increased atmospheric stability over the cold water. The strongest response in terms of surface convergence is found when atmospheric fronts (already characterized by strong surface convergence) cross SST gradients from the warm to the cold side.Using 25 years of ERA5 reanalysis data, it is also found that the wind divergence variability within the MABL (until about 925 hPa) is partially driven by mesoscale SST patterns via their effect on the boundary layer stability. This results in a cloud cover and rainfall response: when a wind blows from warm-to-cold (cold-to-warm) ocean patterns, a converging (diverging) cell is enhanced, increasing (decreasing) low-cloud cover and favouring rainfall. Specifically, strong warm-to-cold fronts (the upper 25th percentile) are associated with a mean increase of cloud cover of 10±5% and a mean increase in the probability of a rain event of 15±6%, with respect to the average values. The cloud and rainfall dependence on SST fronts is more pronounced in fall than in the rest of the year, probably due to the stronger SST gradients present at the end of the summer season. The effects on cloud cover, in particular, are a preferential way through which mesoscale SST structures can impact the radiation budget and, thus, the Earth climate.