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While the ERA5 reanalysis is commonly utilized in climate studies on extratropical cyclones (ETCs), only a few studies have quantified its ability in the representation of ETCs over land. To address this gap, this study evaluates ERA5's skill in representing the ETC‐associated 10‐m wind speed and the precipitation in central and eastern North America during 2005–2019. Hourly data collected from ~3000 stations, amounting to around 420 million reports stored in the Integrated Surface Database, is used as reference. For the spatial‐averaged ETC properties, ERA5 shows a good skill for wind speed with normalized mean bias (NMB) of −0.7% and normalized root‐mean‐square error (NRMSE) of 14.3%, despite a tendency to overestimate low winds and underestimate high winds. The ERA5 skill is worse for precipitation than for wind speed with NMB of −10.4% and NRMSE of 56.5% and a strong tendency to underestimate high values. For both variables, the best and worst performance is found in DJF and JJA, respectively. Negative biases are often identified over regions with stronger precipitation/wind speeds, and a systematic underestimation of wind speed is found over the Rockies with complex topography. Compared to the averaged ETCs, ERA5's performance deteriorates for the top 5% extreme ETCs with a stronger tendency to underestimate both wind speed and precipitation (NMB of −10.2% and −22.6%, respectively). Furthermore, ERA5's skill is worse for local extreme values within ETCs than for spatial averages. Our results highlight some important limitations of the ERA5 reanalysis products for studies looking at the possible impacts of ETCs. [ABSTRACT FROM AUTHOR]

This study investigates the seasonality of near‐surface wind speeds associated with extratropical cyclones (ETCs) over northeastern North America using a global reanalysis data set during 1979–2020. As opposed to most studies that emphasize winter storms, ETCs during the fall exhibit significantly stronger 10‐m winds over this region due to the slightly stronger continental cyclones and significantly weaker low‐level stability during that time of the year. Also, ETCs favor inland lakes and Hudson Bay during the low‐ice‐content fall season, leading to lower surface roughness. Combining these results, we derive simple linear regressions to predict the 10‐m wind speed given three variables: 850‐hPa wind speed, low‐level Richardson number, and surface roughness length. This formula captures the observed seasonality and serves as a valuable tool for cyclone near‐surface wind risk assessment. Plain Language Summary: Extratropical cyclones can bring powerful winds that can cause severe damage to infrastructure. We find that cyclones with severe winds are the most frequent in the fall season over continental northeastern North America. Three reasons are found responsible: stronger continental cyclones, weaker low‐level atmospheric stability, and the lower surface roughness over lakes and Hudson Bay, where cyclones frequently occur in fall. A simple formula that can effectively assess the near‐surface wind speeds associated with cyclones is derived based on these results. Key Points: Extratropical‐cyclone‐associated 10‐m wind speeds are the strongest in the fall season over northeastern North AmericaBesides stronger continental cyclones and 850‐hPa winds, weaker low‐level stability in fall favors stronger 10‐m wind speeds in this regionLinear regression using 850‐hPa wind, Richardson number, and surface roughness well predicts cyclones' 10‐m wind speeds and seasonality [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) in geological formations play a key role in mitigating anthropogenic CO 2 emissions and achieving the aggressive goal of net-zero greenhouse gas emissions. Risk and uncertainty assessment is crucial for ensuring the safety and reliability of geologic carbon storage (GCS) by evaluating CO 2 migration in subsurface, forecasting potential leakage and induced seismicity risks, and optimizing operational and monitoring plans. In this review, the use and progress of risk assessment for GCS over the last few decades are examined. We use the Southwest Regional Partnership on Carbon Sequestration (SWP), which is one of the seven regional partnerships supported by the United States Department of Energy (U.S. DOE), as an example of large-scale CCUS projects in North America. Additionally, future trends and requirements for risk assessment in GCS are discussed. The information provided in this review can help readers understand the significance of risk and uncertainty assessment and apply it effectively in large-scale GCS projects. [Display omitted] • Risk assessment application and progress for geologic CO 2 storage are examined. • Advanced methods and operational/monitoring optimization are discussed. • A 10-year large-scale CCUS project in North America is presented as a case study. • Future trends and requirements for risk assessment are highlighted. [ABSTRACT FROM AUTHOR]

Purpose: Conflicting evidence indicates that HIV seropositivity may influence the outcome of patients with hepatocellular carcinoma (HCC), a leading cause of mortality in people with HIV. We aimed to verify whether HIV affected the overall survival (OS) of patients with HCC, independent of treatment and geographic origin., Patients and Methods: We designed an international multicohort study of patients with HCC accrued from four continents who did not receive any anticancer treatment. We estimated the effect of HIV seropositivity on patients' OS while accounting for common prognostic factors and demographic characteristics in uni- and multivariable models., Results: A total of 1,588 patients were recruited, 132 of whom were HIV positive. Most patients clustered within Barcelona Clinic Liver Cancer (BCLC) C or D criteria (n = 1,168 [74%]) and Child-Turcotte-Pugh (CTP) class B (median score, 7; interquartile range [IQR], 3). At HCC diagnosis, the majority of patients who were HIV-positive (n = 65 [64%]) had been on antiretrovirals for a median duration of 8.3 years (IQR, 8.59 years) and had median CD4 + cell counts of 256 (IQR, 284) with undetectable HIV RNA (n = 68 [52%]). OS decreased significantly throughout BCLC stages 0 to D (16, 12, 7.5, 3.1, and 3 months, respectively; P < .001). Median OS of patients who were HIV-positive was one half that of their HIV-uninfected counterparts (2.2 months [bootstrap 95% CI, 1.2 to 3.1 months] v 4.1 months [95% CI, 3.6 to 4.4 months]). In adjusted analyses, HIV seropositivity increased the hazard of death by 24% ( P = .0333) independent of BCLC ( P < .0001), CTP ( P < .0001), α-fetoprotein ( P < .0001), geographical origin ( P < .0001), and male sex ( P = .0016). Predictors of worse OS in patients who were HIV-positive included CTP ( P = .0071) and α-fetoprotein ( P < .0001)., Conclusion: Despite adequate antiretroviral treatment, HIV seropositivity is associated with decreased survival in HCC, independent of stage, anticancer treatment, and geographical origin. Mechanistic studies investigating the immunobiology of HIV-associated HCC are urgently required.