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The long-term comparison between simulated and observed spectrally resolved radiances can represent a stringent test for the direct verification and improvement of General Circulation Models (GCMs). From the mid of 2000s, stable hyperspectral observations of the Mid-Infrared region (667 to 2750 cm-1) the Earth emission spectrum have been provided by different sensors (e.g., AIRS, IASI and CrIS). In addition, the FORUM mission, selected to be the ninth ESA Earth Explorer mission, will measure, starting from 2027, the terrestrial radiation emitted to space at the top of the atmosphere (TOA) from 100 to 1600 cm-1 filling the observational gap in the far-infrared (FIR) region, from 100 to 667 cm-1. In this work, in anticipation of FORUM measurements, we compare existing IASI observations to radiances simulated on the basis of the atmospheric fields predicted by the EC-Earth GCM (version 3.3.3) in clear-sky conditions. In order to simulate spectra based on the atmospheric and surface state provided by the climate model, the radiative transfer model σ -IASI has been implemented in the Cloud Feedback Model Intercomparison Project (COSP) package. Therefore, on-line simulations provided by EC-Earth model equipped with the new COSP + σ -IASI module have been performed in clear-sky conditions with prescribed sea surface temperature and sea-ice cover, every 6 hours, over a timeframe consistent with the availability of IASI data. Systematic comparisons between observed IASI MetOp-A L1C data and model outputs have been performed in 10 cm-1 spectral intervals, on global and regional scales, by distinguishing the surface type (land, sea). The long term analysis shows a warm bias of the climate model in the roto-vibrational water vapour bands and in the CO2 absorption band. These biases represent a strong evidence of a temperature bias of the model in the upper-troposphere and in the stratosphere, while a cold bias occurs over land. [ABSTRACT FROM AUTHOR]

Climate warming in mountain regions is resulting in glacier shrinking, seasonal snow cover reduction, changes in the amount and seasonality of meltwater runoff, with consequences on water availability. Droughts are expected to become more severe in the future with economical and environmental losses both locally and downstream. Effective adaptation strategies involve multiple time scales, and seasonal forecasts can help in the optimization of the available snow/water resources with lead times of several months. We developed a prototype to generate seasonal forecasts of snow depth and snow water equivalent with starting date November 1st and lead times of 7 months, so up to May 31st of the following year. The prototype has been codesigned with end users in the field of water management, hydropower production and of mountain ski tourism, meeting their needs in terms of indicators, time resolution of the forecasts, visualization of the forecast outputs. In this paper we present the modelling chain, based on the seasonal forecasts of ECMWF and Météo-France seasonal prediction systems, made available through the Copernicus Climate Change Service (C3S) Climate Data Store. Seasonal forecasts of precipitation, near-surface air temperature, radiative fluxes, wind and relative humidity are bias-corrected and downscaled to three sites in the Western Italian Alps, and finally used as input for the physically-based multi-layer snow model SNOWPACK. The RainFARM stochastic downscaling procedure is applied to precipitation data in order to allow an estimate of uncertainties due to the downscaling method. The skill of the prototype in predicting the monthly snow depth evolution from November to May in each season of the hindcast period 1995-2015 are demonstrated using both deterministic and probabilistic metrics. Forecast skills are determined with respect to a simple forecasting method based on the climatology, and station measurements are used as reference data. The prototype shows very good skills at predicting the tercile category, i.e. snow depth below- and above-normal, in the winter (lead time 2-3-4 months) and spring (lead times 5-6-7 months) ahead: snow depth is predicted with higher accuracy (Brier Skill Score) and higher discrimination (Area Under the ROC Curve Skill Score) with respect to a simple forecasting method based on the climatology. Ensemble mean monthly snow depth forecasts are significantly correlated with observations not only at short lead time 1 and 2 months (November and December) but also at lead time 5 and 6 months (March and April) when employing the ECMWFS5 forcing. Moreover the prototype shows skill at predicting extremely dry seasons, i.e. seasons with snow depth below the 10th percentile, while skills at predicting snow depth above the 90th percentile are model-, station- and score-dependent. No remarkable differences are found among the skill scores when the precipitation input is bias-corrected, downscaled or bias-corrected and downscaled compared to the case in which raw data are employed, suggesting that skill scores are weakly sensitive to the treatment of the precipitation input. [ABSTRACT FROM AUTHOR]

This paper documents the global climate model EC-Earth3-AerChem, one of the members of the EC-Earth3 family of models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6). EC-Earth3-AerChem has interactive aerosols and atmospheric chemistry and contributes to the Aerosols and Chemistry Model Intercomparison Project (AerChemMIP). In this paper, we give an overview of the model and describe in detail how it differs from the other EC-Earth3 configurations, and what the new features are compared to the previously documented version of the model (EC-Earth 2.4). We explain how the model was tuned and spun up under pre-industrial conditions and characterize the model's general performance on the basis of a selection of coupled simulations conducted for CMIP6. The mean energy imbalance at the top of the atmosphere in the pre-industrial control simulation is -0.10 ± 0.25 W m-2 and shows no significant drift. The corresponding mean global surface air temperature is 14.05 ± 0.16 °C, with a small drift of -0.075 ± 0.009 °C per century. The model's effective equilibrium climate sensitivity is estimated at 3.9 °C and its transient climate response at 2.1 °C. The CMIP6 historical simulation displays spurious interdecadal variability in Northern Hemisphere temperatures, resulting in a large spread among ensemble members and a tendency to underestimate observed annual surface temperature anomalies from the early 20th century onwards. The observed warming of the Southern Hemisphere is well reproduced by the model. Compared to the ERA5 reanalysis of the European Centre for Medium-Range Weather Forecasts, the ensemble mean surface air temperature climatology for 1995-2014 has an average bias of -0.86 ± 0.35 °C in the Northern Hemisphere and 1.29 ± 0.05 °C in the Southern Hemisphere. The Southern Hemisphere warm bias is largely caused by errors in shortwave cloud radiative effects over the Southern Ocean, a deficiency of many climate models. Changes in the emissions of near-term climate forcers (NTCFs) have significant climate effects from the 20th century onwards. For the SSP3-7.0 shared socio-economic pathway, the model gives a global warming at the end of the 21st century (2091-2100) of 4.9 °C above the pre-industrial mean. A 0.5 °C stronger warming is obtained for the AerChemMIP scenario with reduced emissions of NTCFs. With concurrent reductions of future methane concentrations, the warming is projected to be reduced by 0.5 °C. [ABSTRACT FROM AUTHOR]

Before about 500 million years ago, most probably our planet experienced temporary snowball conditions, with continental and sea ices covering a large fraction of its surface. This points to a potential bistability of Earth's climate that can have at least two different (statistical) equilibrium states for the same external forcing (i.e. solar radiation). Here, we explore the probability of finding bistable climates in Earth-like exoplanets and consider the properties of planetary climates obtained by varying the semimajor orbital axis (thus, received stellar radiation), eccentricity and obliquity, and atmospheric pressure. To this goal, we use the Earth-like planet surface temperature model (ESTM), an extension of one-dimensional Energy Balance Models developed to provide a numerically efficient climate estimator for parameter sensitivity studies and long climatic simulations. After verifying that the ESTM is able to reproduce Earth climate bistability, we identify the range of parameter space where climate bistability is detected. An intriguing result of this work is that the planetary conditions that support climate bistability are remarkably similar to those required for the sustenance of complex, multicellular life on the planetary surface. The interpretation of this result deserves further investigation, given its relevance for the potential distribution of life in exoplanetary systems. [ABSTRACT FROM AUTHOR]

We numerically explore the dynamics of an incompressible fluid heated from below, boundedby free-slip horizontal plates and periodic lateral boundary conditions, subject to rapidrotation about a distant axis that is tilted with respect to the gravity vector (supposed vertical).The angle φ between the rotation axis and the horizontal plane measures the tilting of therotation axis and it can be taken as a proxy for latitude, if we think of a local Cartesianrepresentation of the convective dynamics in a rotating fluid shell. The results of thesimulations indicate the existence of three different convective regimes, depending on thevalue of φ: (1) sheared, intermittent large-scale winds in the direction perpendicular to theplane defined by the gravity and rotation vectors, when rotation is "horizontal" (φ = 0); (2) alarge-scale cyclonic vortex tilted along the rotation axis, when the angle between the rotationaxis and the gravity vector is relatively small (φ between about 45∘ and 90∘); (3)a new intermediate regime characterized by vertically sheared large-scale windsperpendicular to both gravity and rotation. In this regime, the winds are organized inbands that are tilted along the rotation axis, with unit horizontal wavenumber inthe plane defined by gravity and rotation, at values of φ less than about 60∘. Thisintermediate solution, studied for the first time in this work, is characterized by weakervertical heat transport than the cases with large-scale vortices. For intermediatevalues of φ (between about 45∘ and 60∘) the banded, sheared solution coexistswith the large-scale vortex solution, and different initial conditions lead to one orthe other dynamical behavior. A discussion of the possible implications of theseresults for the dynamics of rapidly-rotating planetary atmospheres is provided. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs) are shed by many different cell types. Their nucleic acids content offers new opportunities for biomarker research in different solid tumors. The role of EV RNA in prostate cancer (PCa) is still largely unknown. EVs were isolated from different benign and malignant prostate cell lines and blood plasma from patients with PCa ( n = 18) and controls with benign prostatic hyperplasia (BPH) ( n = 7). Nanoparticle tracking analysis (NTA), Western blot, electron microscopy, and flow cytometry analysis were used for the characterization of EVs. Non-coding RNA expression profiling of PC3 metastatic PCa cells and their EVs was performed by next generation sequencing (NGS). miRNAs differentially expressed in PC3 EVs were validated with qRT-PCR in EVs derived from additional cell lines and patient plasma and from matched tissue samples. 92 miRNAs were enriched and 48 miRNAs were depleted in PC3 EVs compared to PC3 cells, which could be confirmed by qRT-PCR. miR-99b-5p was significantly higher expressed in malignant compared to benign EVs. Furthermore, expression profiling showed miR-10a-5p ( p = 0.018) and miR-29b-3p ( p = 0.002), but not miR-99b-5p, to be overexpressed in plasma-derived EVs from patients with PCa compared with controls. In the corresponding tissue samples, no significant differences in the miRNA expression could be observed. We thus propose that EV-associated miR-10a-5p and miR-29b-3p could serve as potential new PCa detection markers., Competing Interests: The authors declare no conflicts of interest.