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Large-eddy simulations (LESs) are conducted for each day of the intensive observation periods (IOPs) of the Green Ocean Amazon (GoAmazon) field campaign to characterize the updrafts and microphysics within deep convective cores while contrasting those properties between Amazon wet and dry seasons. Mean Doppler velocity (Vdop) values simulated using LESs are compared with 2-year measurements from a radar wind profiler (RWP) as viewed by statistical composites separated according to wet- and dry-season conditions. In the observed RWP and simulated LES Vdop composites, we find more intense low-level updraft velocity, vigorous graupel generation, and intense surface rain during the dry periods compared with the wet periods. To investigate coupled updraft–microphysical processes further, single-day golden cases are selected from the wet and dry periods to conduct detailed cumulus thermal tracking analysis. Tracking analysis reveals that simulated dry-season environments generate more droplet-loaded low-level thermals than wet-season environments. This tendency correlates with seasonal contrasts in buoyancy and vertical moisture advection profiles in large-scale forcing. Employing a normalized time series of mean thermal microphysics, the simulated cumulus thermals appear to be the primary generator of cloud droplets. When subsequent thermals penetrate the ice crystal layer, droplets within the thermals interact with entrained ice crystals, which enhances riming in the thermals. This appears to be a production pathway of graupel/hail particles within simulated deep convective cores. In addition, less-diluted dry-case thermals tend to be elevated higher, and graupel grows further during sedimentation after spilling out from thermals. Therefore, greater concentrations of low-level moist thermals likely result in more graupel/hail production and associated dry-season convective vigor.

Intro: Detecting and responding to acute public health threats is one of the World Health Organization's (WHO) most important activities. Therefore, WHO established a unique approach for the global detection and verification of events of potential international public health concern and adopted an all-hazards approach as part of the International Health Regulations (2005), moving beyond a focus on infectious diseases only. Here, we analysed 20-year trends of acute public health events globally. Methods: We extracted data on acute public health events reported between 2002 and 2021 from the Event Management System (EMS). EMS is an internal WHO web-based platform used for tracking health threats globally. We examined the designation, source and hazard of events by WHO Region and over time by calculating descriptive statistics and trends using R. Findings: Between 2002 and 2021, 7572 events were recorded globally in EMS, ranging from 231 to 576 per year. Of these, 5466 (76%) were designated as substantiated, deemed true acute public health events, and only a small proportion (379, 5%) were unverifiable or had no designation. During the 20-year period, substantiated events were greatest in the WHO African Region (1684 events, 31%) and the WHO Region of the Americas (1312 events, 24%) and, similarly, by year, the burden was highest in those WHO regions. Globally, over time, two-thirds (3536, 65%) of substantiated events were initially reported by WHO and infectious diseases (4298, 79%) were the predominant cause of public health events. However, other causes, including animal origin or zoonoses were also important and disaster related events were on the rise in recent years, particularly in some WHO Regions. Conclusion: WHO has a robust system for global disease detection but health threats are continuously evolving. The impact of climate change and zoonoses is becoming more pronounced, emphasizing the importance of a One Health approach for disease detection.

Demand-side water management in developing countries should ideally involve controlling the use of piped water supply and securing water sources that complement it to ensure sustainable use. To investigate the feasibility of incorporating these factors, we conducted a survey in Galle, Sri Lanka. First, an end-use survey was conducted to understand current and near future water use. The results indicated that the toilet, kitchen, clothes washing, and bathing related per capita water consumption in Galle was significantly lower than that in Colombo. The results also suggested that increases in indoor water needs cannot be supplemented via piped water supply only; it is necessary to consider alternative water sources, such as rainwater. Second, the residents' acceptance of rainwater usage for each indoor use was surveyed and it was found that acceptance depended on knowledge levels regarding rainwater harvesting. HIGHLIGHTS Residential water end-use in some places in Sri Lanka was investigated.; People in the capital city use more water than those in the regional city.; Toilet, kitchen, clothes washing, and bathing water usage varied based on region.; Tap water supply alone may not be sufficient to meet increasing water demand.; Rainwater acceptance was influenced by the knowledge level about its specific use.;

One fundamental question about atmospheric moist convection processes that remains debated is whether, or under which conditions, a relevant variability in background aerosol concentrations may have a significant dynamical impact on convective clouds and their associated precipitation. Furthermore, current climate models must parameterize both the microphysical and the cumulus convection processes, but this is usually implemented separately, whereas in nature there is a strong coupling between them. As a first step to improve our understanding of these two problems, we investigate how aerosol concentrations modify key properties of updrafts in eight large-eddy-permitting regional simulations of a case study of scattered convection over Houston, Texas, in which convection is explicitly simulated and microphysical processes are parameterized. Dynamical and liquid-phase microphysical responses are investigated using the following two different reference frames: static cloudy updraft grid cells versus tracked cumulus thermals. In both frameworks, we observe the expected microphysical responses to higher aerosol concentrations, such as higher cloud number concentrations and lower rain number concentrations. In terms of the dynamical responses, both frameworks indicate weak impacts of varying aerosol concentrations relative to the noise between simulations over the observationally derived range of aerosol variability for this case study. On the other hand, results suggest that thermals are more selective than cloudy updraft grid cells in terms of sampling the most active convective air masses. For instance, vertical velocity from thermals is significantly higher at upper levels than when sampled from cloudy updraft grid points, and several microphysical variables have higher average values in the cumulus thermal framework than in the cloudy updraft framework. In addition, the thermal analysis is seen to add rich quantitative information about the rates and covariability of microphysical processes spatially and throughout tracked thermal lifecycles, which can serve as a stronger foundation for improving subgrid-scale parameterizations.

To probe the potential value of a radar-driven field campaign to constrain simulation of isolated convection subject to a strong aerosol perturbation, convective cells observed by the operational KHGX weather radar in the vicinity of Houston, Texas, are examined individually and statistically. Cells observed in a single case study of onshore flow conditions during July 2013 are first examined and compared with cells in a regional model simulation. Observed and simulated cells are objectively identified and tracked from observed or calculated positive specific differential phase (KDP) above the melting level, which is related to the presence of supercooled liquid water. Several observed and simulated cells are subjectively selected for further examination. Below the melting level, we compare sequential cross sections of retrieved and simulated raindrop size distribution parameters. Above the melting level, we examine time series of KDP and radar differential reflectivity (ZDR) statistics from observations and calculated from simulated supercooled rain properties, alongside simulated vertical wind and supercooled rain mixing ratio statistics. Results indicate that the operational weather radar measurements offer multiple constraints on the properties of simulated convective cells, with substantial value added from derived KDP and retrieved rain properties. The value of collocated three-dimensional lightning mapping array measurements, which are relatively rare in the continental US, supports the choice of Houston as a suitable location for future field studies to improve the simulation and understanding of convective updraft physics. However, rapid evolution of cells between routine volume scans motivates consideration of adaptive scan strategies or radar imaging technologies to amend operational weather radar capabilities. A 3-year climatology of isolated cell tracks, prepared using a more efficient algorithm, yields additional relevant information. Isolated cells are found within the KHGX domain on roughly 40 % of days year-round, with greatest concentration in the northwest quadrant, but roughly 5-fold more cells occur during June through September. During this enhanced occurrence period, the cells initiate following a strong diurnal cycle that peaks in the early afternoon, typically follow a south-to-north flow, and dissipate within 1 h, consistent with the case study examples. Statistics indicate that ∼ 150 isolated cells initiate and dissipate within 70 km of the KHGX radar during the enhanced occurrence period annually, and roughly 10 times as many within 200 km, suitable for multi-instrument Lagrangian observation strategies. In addition to ancillary meteorological and aerosol measurements, robust vertical wind speed retrievals would add substantial value to a radar-driven field campaign.

Multi-Doppler-radar network observations have been used in different configurations over the last several decades to conduct three-dimensional wind retrievals in mesoscale convective systems. Here, the impacts of the selected radar volume coverage pattern (VCP), the sampling time for the VCP, the number of radars used, and the added value of advection correction on the retrieval of the vertical air motion in the upper part of convective clouds are examined using the Weather Research and Forecasting (WRF) model simulation, the Cloud Resolving Model Radar SIMulator (CR-SIM), and a three-dimensional variational multi-Doppler-radar retrieval technique. Comparisons between the model truth (i.e., WRF kinematic fields) and updraft properties (updraft fraction, updraft magnitude, and mass flux) retrieved from the CR-SIM-generated multi-Doppler-radar field are used to investigate these impacts. The findings are that (1) the VCP elevation strategy and sampling time have a significant effect on the retrieved updraft properties above 6 km in altitude; (2) 2 min or shorter VCPs have small impacts on the retrievals, and the errors are comparable to retrievals using a snapshot cloud field; (3) increasing the density of elevation angles in the VCP appears to be more effective to reduce the uncertainty than an addition of data from one more radar, if the VCP is performed in 2 min; and (4) the use of dense elevation angles combined with an advection correction applied to the 2 min VCPs can effectively improve the updraft retrievals, but for longer VCP sampling periods (5 min) the value of advection correction is challenging. This study highlights several limiting factors in the retrieval of upper-level vertical velocity from multi-Doppler-radar networks and suggests that the use of rapid-scan radars can substantially improve the quality of wind retrievals if conducted in a limited spatial domain.

To support the assessments of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), the IPBES Expert Group on Scenarios and Models is carrying out an intercomparison of biodiversity and ecosystem services models using harmonized scenarios (BES-SIM). The goals of BES-SIM are (1) to project the global impacts of land-use and climate change on biodiversity and ecosystem services (i.e., nature's contributions to people) over the coming decades, compared to the 20th century, using a set of common metrics at multiple scales, and (2) to identify model uncertainties and research gaps through the comparisons of projected biodiversity and ecosystem services across models. BES-SIM uses three scenarios combining specific Shared Socio-economic Pathways (SSPs) and Representative Concentration Pathways (RCPs) – SSP1xRCP2.6, SSP3xRCP6.0, SSP5xRCP8.6 – to explore a wide range of land-use change and climate change futures. This paper describes the rationale for scenario selection, the process of harmonizing input data for land use, based on the second phase of the Land Use Harmonization Project (LUH2), and climate, the biodiversity and ecosystem services models used, the core simulations carried out, the harmonization of the model output metrics, and the treatment of uncertainty. The results of this collaborative modeling project will support the ongoing global assessment of IPBES, strengthen ties between IPBES and the Intergovernmental Panel on Climate Change (IPCC) scenarios and modeling processes, advise the Convention on Biological Diversity (CBD) on its development of a post-2020 strategic plans and conservation goals, and inform the development of a new generation of nature-centred scenarios.

Domestic animals, including ruminants, can synthesize vitamin C (VC) in their liver; as such, the dietary requirement for VC has not been confirmed in these animals. The adequacy of VC has been evaluated by quantifying VC levels in plasma, but the reported values in bovine plasma have been widely variable. Plasma VC concentration is decreased by heat stress, hepatic lesions, fattening, and infectious diseases such as mastitis in cattle. Therefore, VC supplementation is potentially beneficial for cattle with low plasma VC concentration. This review discusses the methods for determination of plasma VC concentration in cattle, VC nutrition, and the efficacy of VC supplementation in calves, dairy cattle, and beef cattle. Additionally I propose a reference range for plasma VC concentration in Japanese Black cattle.

Using the 15N2 tracer method and high-sensitivity δ15N analytical systems, we determined N2 fixation rates for ocean samples by dividing them into particulate (>0.7 μm) and filtrate (2 fixation in the filtrate fraction had been ignored in previous studies, we found a significant N2 fixation rates in the filtrate fraction in our study. The areal N2 fixation rates in the western North Pacific Ocean estimated from the particulate fraction varied from -2 d−1, and those rates estimated from the filtrate fraction ranged from -2 d−1. Thus, N2 fixation in the filtrate fraction accounts for on average 50% (ranging from 2 fixation rates. If these results are confirmed generally in the ocean, the new total N2 fixation flux, which includes fixation in the filtrate fraction, possibly doubles the original estimates; therefore, the revised influx may reduce the imbalance in the global oceanic fixed nitrogen budget.

Recently, a multi-scale modeling system with unified physics was developed at NASA Goddard. It consists of (1) a cloud-resolving model (CRM), (2) a regional-scale model, the NASA unified Weather Research and Forecasting Model (WRF), and (3) a coupled CRM-GCM (general circulation model, known as the Goddard Multi-scale Modeling Framework or MMF). The same cloud-microphysical processes, long- and short-wave radiative transfer and land-surface processes are applied in all of the models to study explicit cloud-radiation and cloud-surface interactive processes in this multi-scale modeling system. This modeling system has been coupled with a multi-satellite simulator for comparison and validation with NASA high-resolution satellite data. This paper reviews the development and presents some applications of the multi-scale modeling system, including results from using the multi-scale modeling system to study the interactions between clouds, precipitation, and aerosols. In addition, use of the multi-satellite simulator to identify the strengths and weaknesses of the model-simulated precipitation processes will be discussed as well as future model developments and applications.

The genome of Mycobacterium tuberculosis H37Rv contains three contiguous genes (plc-a, plc-b and plc-c) which are similar to the Pseudomonas aeruginosa phospholipase C (PLC) genes. Expression of mycobacterial PLC-a and PLC-b in E. coli and M. smegmatis has been reported, whereas expression of the native proteins in M. tuberculosis H37Rv has not been demonstrated. The objective of the present study was to demonstrate that native PLC-a is expressed in M. tuberculosis H37Rv. Sera from mice immunized with recombinant PLC-a expressed in E. coli were used in immunoblots to evaluate PLC-a expression. The immune serum recognized a 49-kDa protein in immunoblots against M. tuberculosis extracts. No bands were visible in M. tuberculosis culture supernatants or extracts from M. avium, M. bovis and M. smegmatis. A 550-bp DNA fragment upstream of plc-a was cloned in the pJEM12 vector and the existence of a functional promoter was evaluated by detection of ß-galactosidase activity. ß-Galactosidase activity was detected in M. smegmatis transformed with recombinant pJEM12 grown in vitro and inside macrophages. The putative promoter was active both in vitro and in vivo, suggesting that expression is constitutive. In conclusion, expression of non-secreted native PLC-a was demonstrated in M. tuberculosis.

No abstract available. doi:10.2204/iodp.sd.6.09.2008