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There is a growing understanding of the role that bedrock weathering can play as a source of nitrogen (N) to soils, groundwater and river systems. The significance is particularly apparent in mountainous environments where weathering fluxes can be large. However, our understanding of the relative contributions of rock-derived, or geogenic, N to the total N supply of mountainous watersheds remains poorly understood. In this study, we develop the High-Altitude Nitrogen Suite of Models (HAN-SoMo), a watershed-scale ensemble of process-based models to quantify the relative sources, transformations, and sinks of geogenic and atmospheric N through a mountain watershed. Our study is based in the East River Watershed (ERW) in the Upper Colorado River Basin. The East River is a near-pristine headwater watershed underlain primarily by an N-rich Mancos Shale bedrock, enabling the timing and magnitude of geogenic and atmospheric contributions to watershed scale dissolved N-exports to be quantified. Several calibration scenarios were developed to explore equifinality using >1600 N concentration measurements from streams, groundwater, and vadose zone samples collected over the course of four years across the watershed. When accounting for recycling of N through plant litter turnover, rock weathering accounts for approximately 12% of the annual dissolved N sources to the watershed in the most probable calibration scenario (0-31% in other scenarios), and 21% (0-44% in other scenarios) when considering only "new" N sources (i.e. geogenic and atmospheric). On an annual scale, instream dissolved N elimination, plant turnover (including cattle grazing) and atmospheric deposition are the most important controls on N cycling.

The goal of the two Power of Data (POD) projects was to increase science, technology and math skills through the implementation of project-based learning modules that teach students how to solve problems through data collection and analysis utilizing geospatial technologies. Professional development institutes in two formats were offered to encourage teachers to implement the modules. We compared teacher learning, teacher implementation, and student learning from the two different professional development formats to examine how each format supported teachers to implement the modules, and, ultimately, improve student understanding. Teacher surveys, content and technology assessments, classroom observations, student assessments, and student work samples were analyzed for comparison between a two-week summer institute and monthly meetings held throughout the academic year. Teachers and students from both formats showed improvement in all areas assessed, yet there was not a large effect on student outcomes based on the delivery format between the professional development sessions.

Rising organic charge in northern freshwaters is attributed to increasing levels of dissolved natural organic matter (DNOM) and changes in water chemistry. Organic charge concentration may be determined through charge balance calculations (Org.−) or modelled (OAN−) using the Oliver and Hruška conceptual models, which are based on the density of weak acid functional sites (SD) present in DNOM. The charge density (CD) is governed by SD as well as protonation and complexation reactions on the functional groups. These models use SD as a key parameter to empirically fit the model to Org.−. Utilizing extensive water chemistry datasets, this study shows that spatial and temporal differences in SD and CD are influenced by variations in the humic-to-fulvic ratio of DNOM, organic aluminum (Al) complexation, and the mole fraction of CD to SD, which is governed by acidity. The median SD values obtained for 44 long-term monitored acid-sensitive lakes were 11.1 and 13.9 µEq/mg C for the Oliver and Hruška models, respectively. Over 34 years of monitoring, the CD increased by 70%, likely due to rising pH and declining Al complexation with DNOM. Present-day median SD values for the Oliver and Hruška models in 16 low-order streams are 13.8 and 15.8 µEq/mg C, respectively, and 10.8 and 12.5 µEq/mg C, respectively, in 10 high-order rivers. [ABSTRACT FROM AUTHOR]

The article delves into the systemic shortcomings within the realm of Supreme Court judicial ethics, underscoring the necessity for a comprehensive code of conduct complemented by robust enforcement measures. It elucidates how the erosion of public trust and the legitimacy of the Court stem from these deficiencies. It emphasizes the imperative of preserving the perception of impartiality, the discussion transcends partisan divides.

Despite high potential benefits, the development of seasonal forecasting tools in the water sector has been slower than in other sectors. Here we assess the skill of seasonal forecasting tools for lake and reservoir set up at four sites in Australia and Europe. These tools, as previously presented, consist of coupled hydrological catchment and lake models forced with seasonal climate forecast ensembles to provide probabilistic predictions of seasonal anomalies in water discharge, temperature and ice-off. Successful implementation requires a rigorous assessment of the tools' predictive skill and an apportionment of the predictability between legacy effects and input data. To this end, models were forced with two meteorological datasets from the European Centre for Medium Range Weather Forecasts (ECMWF), the seasonal forecasts SEAS5 and the ERA5 reanalysis. Historical skill was assessed by comparing both model outputs, i.e., seasonal lake hindcasts (forced with SEAS5) and pseudo-observations (forced with ERA5). The skill of the seasonal lake hindcasts was generally low, but higher than SEAS5 climate hindcasts. Nevertheless, lake and SEAS5 windows of opportunity were identified, although they were not always synchronous, raising questions on the source of the predictability. A set of sensitivity analyses showed that most of the forecasting skill originates from legacy effects, although during winter and spring in Norway some skill was coming from SEAS5 over the target season. When SEAS5 hindcasts were skillful, additional predictability originates from the interaction between legacy and SEAS5 skill. We conclude that a climatology driven forecast is currently likely to yield higher quality forecasts. [ABSTRACT FROM AUTHOR]

It took nearly 100 years after the United States gained its independence for African American men to secure the right to vote, and almost 150 years for African American women. A right perceived—though not de facto honored—as fundamental for all Americans today was fought for in a war less than two centuries ago, costing 620,000 lives. The country quite literally divided over the idea that African Americans should be afforded basic human rights. Today, resistance to the franchise—to what the mythology of America “stands for”—is not remotely erased, but rather, newly emboldened, even if it masquerades under more obfuscating terminology. Acknowledgement of contemporary racism in the motivation and passage of voting legislation remains highly controversial. The current U.S. Supreme Court majority interprets gradual increases in voter registration as conclusive evidence that historical discrimination in voting has been eradicated. Ostensible judicial minimalists in the Court majority have effectively usurped congressional fact-finding as to the ongoing necessity of antidiscriminatory measures. [ABSTRACT FROM AUTHOR]