Implementing detailed nucleation predictions in the Earth system model EC-Earth3.3.4: sulfuric acid–ammonia nucleation

Representing detailed atmospheric aerosol processes in global Earth system models (ESMs) has proven to be challenging from both a computational and a parameterization perspective. The representation of secondary organic aerosol (SOA) formation and new particle formation (NPF) in large ESMs is generally constructed with low detail to save computational costs. The simplification could result in losing the representation of some processes. In this study, we test and evaluate a new approach for improving the description of NPF processes in the ESM EC-Earth3 (ECE3) without significant additional computational burden. The current NPF scheme in EC-Earth3.3.4 is derived from the nucleation of low-volatility organic vapors and sulfuric acid (H2SO4) together with a homogeneous water–H2SO4 nucleation scheme. We expand the existing schemes and introduce a new lookup table approach that incorporates detailed formation rate predictions through molecular modeling of sulfuric acid–ammonia nucleation (H2SO2–NH3). We apply tables of particle formation rates for H2SO2–NH3 nucleation, including dependence on temperature, atmospheric ion production rate, and molecular cluster scavenging sink. The resulting differences between using the H2SO4–NH3 nucleation in ECE3 and the original default ECE3 scheme are evaluated and compared with a focus on changes in the aerosol composition, cloud properties, and radiation balance. From this new nucleation scheme, EC-Earth3's global average aerosol concentrations in the sub-100 nm sizes increased by 12 %–28 %. Aerosol concentrations above 100 nm and the direct radiative effect (in W m−2) showed only minor differences upon changing of the nucleation scheme. However, the radiative effect from clouds affected by aerosols from the new nucleation scheme resulted in a global decrease (cooling effect) by 0.28–1 W m−2. The modeled aerosol concentrations were compared to observed measurements at various stations. In most cases, the new NPF predictions (H2SO2–NH3) performed better at stations where previous underestimations for aerosol concentrations occurred.</p

Experimental investigation and modelling of the transformation of illicit drugs in a pilot-scale sewer system

In-sewer stability of illicit drug biomarkers has been evaluated by several reactor-based studies but less has been done in sewer pipes. Experiments conducted in sewer pipes have advantages over lab-scale reactors in providing more realistic biomarker stability due to the flow and biological dynamics. This study assessed the transportation and transformation of seven illicit drug biomarker compounds in a pilot-scale rising main and a gravity sewer pipe. Biomarkers presented diverse stability patterns in the pilot sewers, based on which a drug transformation model was calibrated. This model was subsequently validated using transformation datasets from literature, aiming to demonstrate the predictability of the pilot-based transformation coefficients under varying sewer conditions. Furthermore, transformation coefficients for five investigated biomarkers were generated from four studies and their prediction capabilities under the pilot sewer conditions were jointly assessed using performance statistics. The transformation model was successful in simulating the in-sewer stability for most illicit drugs. However, further study is required to delineate the sources and pathways for those compounds with potential formations to be simulated in the transformation model. Overall, the transformation model calibrated using the pilot-sewer data is a credible tool for the application of wastewater-based epidemiology

Systematic evaluation of biomarker stability in pilot scale sewer pipes

Transformation of biomarkers (or their stability) during sewer transport is an important issue for wastewater-based epidemiology (WBE). Most studies so far have been conducted in the laboratory, which usually employed unrealistic conditions. In the present study, we utilized a pilot sewer system including a gravity pipe and a rising main pipe to investigate the fate of 24 pharmaceutical biomarkers. A programmable logic controller was used to control and monitor the system including sewer operational conditions and wastewater properties. Sequential samples were collected that can represent hydraulic retention time (HRT) of up to 8 h in a rising main and 4 h in a gravity sewer. Wastewater parameters and biomarker concentrations were analysed to evaluate the stability and transformation kinetics. The wastewater parameters of the pilot system were close to the conditions of real sewers. The findings of biomarker transformation were also close to real sewer data with seventeen biomarkers reported as stable while buprenorphine, caffeine, ethyl-sulfate, methadone, paracetamol, paraxanthine and salicylic acid degraded to variable extents. Both zero-order and first-order kinetics were used to model the degradation of unstable biomarkers and interestingly the goodness of fit R for the zero-order model was higher than the first-order model for all unstable biomarkers in the rising main. The pilot sewer system simulates more realistic conditions than benchtop laboratory setups and may provide a more accurate approach for assessing the in-sewer transformation kinetics and stability of biomarkers

The Fire Modeling Intercomparison Project (FireMIP), phase 1: experimental and analytical protocols

The important role of fire in regulating vegetation community composition and contributions to emissions of greenhouse gases and aerosols make it a critical component of dynamic global vegetation models and Earth system models. Over two decades of development, a wide variety of model structures and mechanisms have been designed and incorporated into global fire models, which have been linked to different vegetation models. However, there has not yet been a systematic examination of how these different strategies contribute to model performance. Here we describe the structure of the first phase of the Fire Model Intercomparison Project (FireMIP), which for the first time seeks to systematically compare a number of models. By combining a standardized set of input data and model experiments with a rigorous comparison of model outputs to each other and to observations, we will improve the understanding of what drives vegetation fire, how it can best be simulated, and what new or improved observational data could allow better constraints on model behavior. Here we introduce the fire models used in the first phase of FireMIP, the simulation protocols applied, and the benchmarking system used to evaluate the models

Part-time hospitalisation and stigma experiences: a study in contemporary psychiatric hospitals

Background: Because numerous studies have revealed the negative consequences of stigmatisation, this study explores the determinants of stigma experiences. In particular, it examines whether or not part-time hospitalisation in contemporary psychiatric hospitals is associated with less stigma experiences than full-time hospitalisation. Methods: Survey data on 378 clients of 42 wards from 8 psychiatric hospitals are used to compare full-time clients, part-time clients and clients receiving part-time care as aftercare on three dimensions of stigma experiences, while controlling for symptoms, diagnosis and clients' background characteristics. Results: The results reveal that part-time clients without previous full-time hospitalisation report less social rejection than clients who receive full-time hospitalisation. In contrast, clients receiving part-time treatment as aftercare do not differ significantly from full-time clients concerning social rejection. No significant results for the other stigma dimensions were found. Conclusion: Concerning social rejection, immediate part-time hospitalisation could be recommended as a means of destigmatisation for clients of contemporary psychiatric hospitals

The EC-Earth3 Earth system model for the Coupled Model Intercomparison Project 6

The Earth system model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major model configurations, a methodology for ensuring the simulations are comparable across different high-performance computing (HPC) systems, and with the physical performance of base configurations over the historical period. The variety of possible configurations and sub-models reflects the broad interests in the EC-Earth community. EC-Earth3 key performance metrics demonstrate physical behavior and biases well within the frame known from recent CMIP models. With improved physical and dynamic features, new Earth system model (ESM) components, community tools, and largely improved physical performance compared to the CMIP5 version, EC-Earth3 represents a clear step forward for the only European community ESM. We demonstrate here that EC-Earth3 is suited for a range of tasks in CMIP6 and beyond

Experimental Investigation and Modeling of the Transformation of Illicit Drugs in a Pilot-Scale Sewer System

In-sewer stability of illicit drug biomarkers has been evaluated by several reactor-based studies, but less has beendone in sewer pipes. Experiments conducted in sewer pipes have advantages over lab-scale reactors in providing more realisticbiomarker stability due to theflow and biological dynamics. This study assessed the transportation and transformation of sevenillicit drug biomarker compounds in a pilot-scale rising main and a gravity sewer pipe. Biomarkers presented diverse stabilitypatterns in the pilot sewers, based on which a drug transformation model was calibrated. This model was subsequently validatedusing transformation data sets from the literature, aiming to demonstrate the predictability of the pilot-based transformationcoefficients under varying sewer conditions. Furthermore, transformation coefficients forfive investigated biomarkers weregenerated from four studies, and their prediction capabilities under the pilot-sewer conditions were jointly assessed usingperformance statistics. The transformation model was successful in simulating the in-sewer stability for most illicit drugs.However, further study is required to delineate the sources and pathways for those compounds with potential formations to besimulated in the transformation model. Overall, the transformation model calibrated using the pilot-sewer data is a credible toolfor the application of wastewater-based epidemiology