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There is increasing interest in science curricula that engage students in scientific practices to deepen their understanding of the core ideas of the field. There are, however, few examples of their designs or assessments available for use as guides for understanding the strengths and weaknesses of particular designs. We offer a summary of our experience in designing and assessing a skills-based geoscience curriculum contextualized within a recently proposed, generalized framework for curricular designs and assessment. Our novel approach to curriculum assessment, with its emphasis on ensuring that the skills highlighted in different courses align with the objectives of the curriculum, is meant to complement more-direct assessments of student mastery of various skills. Assessment results reveal good alignment of course and curricular objectives, in some cases, whereas other parts of the curriculum require refinement. The most challenging of which is the failure of the introductory-level courses to emphasize the process of science. That result is consistent with recent work demonstrating that current approaches to teaching the nature of science are often ineffective. Thus, some of the most challenging problems with more traditional curricula, such as how to help students develop a more-advanced understanding of the nature of science, are not necessarily solved by focusing curricula on the integration of skills with content.

Uncertainty attribution in water supply forecasting is crucial to improve forecast skill and increase confidence in seasonal water management planning. We develop a framework to quantify fractional forecast uncertainty and partition it between (1) snowpack quantification methods, (2) variability in post‐forecast precipitation, and (3) runoff model errors. We demonstrate the uncertainty framework with statistical runoff models in the upper Tuolumne and Merced River basins (California, USA) using snow observations at two endmember spatial resolutions: a simple snow pillow index and full‐catchment snow water equivalent (SWE) maps at 50 m resolution from the Airborne Snow Observatories. Bayesian forecast simulations demonstrate a nonlinear decrease in the skill of statistical water supply forecasts during warm snow droughts, when a low fraction of winter precipitation remains as SWE. Forecast skill similarly decreases during dry snow droughts, when winter precipitation is low. During a shift away from snow‐dominance, the uncertainty of forecasts using snow pillow data increases about 1.9 times faster than analogous forecasts using full‐catchment SWE maps in the study area. Replacing the snow pillow index with full‐catchment SWE data reduces statistical forecast uncertainty by 39% on average across all tested climate conditions. Attributing water supply forecast uncertainty to reducible error sources reveals opportunities to improve forecast reliability in a warmer future climate. [ABSTRACT FROM AUTHOR]

The Northeast United States exhibits significant spatial heterogeneity in flood seasonality, with spring snowmelt‐driven floods historically dominating northern areas, while other regions show more varied flood seasonality. While it is well documented that since 1996 there has been a marked increase in extreme precipitation across this region, the response of flood seasonality to these changes in extreme precipitation and the spatial distribution of these effects remain uncertain. Here we show that, historically, snowmelt‐dominated northern regions were relatively insensitive to changes in extreme precipitation. However, with climate warming, the dominance of snowmelt floods is decreasing and thus the extreme flood regimes in northern regions are increasingly susceptible to changes in extreme precipitation. While extreme precipitation increased everywhere in the Northeastern United States in 1996, it has since returned to near pre‐1996 levels in the coastal north while remaining elevated in the inland north. Thus, the inland north region has and continues to experience the greatest changes in extreme flooding seasonality, including a substantial rise in floods outside the historical spring flood season, particularly in smaller watersheds. Further analysis reveals that while early winter floods are increasingly common, the magnitude of cold season floods (Nov‐May) have remained unchanged over time. In contrast, warm season floods (June‐Oct), historically less significant, are now increasing in both frequency and magnitude in the inland north. Our results highlight that treating the entire Northeast as a uniform hydroclimatic region conceals significant regional variations in extreme discharge trends and, more generally, climate warming will likely increase the sensitivity of historically snowmelt dominated watersheds to extreme precipitation. Understanding this spatial variability in increased extreme precipitation and increased sensitivity to extreme precipitation is crucial for enhancing disaster preparedness and refining water management strategies in affected regions. [ABSTRACT FROM AUTHOR]

Creating effective computer-based learning exercises requires an understanding of optimal user interface designs for improving higher order cognitive skills. Using an online volcanic crisis simulation previously shown to improve decision making skill, we find that a user interface using a graphical presentation of the volcano monitoring data reduces the effectiveness of the exercise compared to an informationally equivalent text-based data presentation format. Results are consistent with earlier work demonstrating that the over-automation of quantitative analyses in computer-based learning reduces their effectiveness in improving higher order skills. Additional research is critically needed to clarify the conditions under which user interfaces can be optimized for ease of use while not sacrificing the exercises' effectiveness in improving higher order cognitive skills.

Computer-assisted instruction (CAI) has been shown to enhance rote memory skills and improve higher order critical thinking skills. The challenge now is to identify what aspects of CAI improve which specific higher-order skills. This study focuses on the effectiveness of using CAI to teach logarithmic graphing and dimensional analysis. Two groups of ninth graders participated in a one-class period laboratory. Experiment 1 compared a fully automated computer laboratory to an equivalent paper-and-pencil exercise. Experiment 2 compared the same automated computer laboratory in Experiment 1 with a revised, less automated computer version. Both the paper-and-pencil exercise and the less automated computer exercise required students to perform basic mathematical calculations. The results from a post-test revealed that very few students were able to master the complex task of dimensional analysis, but students who took the paper-based and revised, less automated version scored higher overall. These results imply that students required to perform basic calculations had a better understanding of the lab as a whole. These results suggest that until students master basic skills, they do not have the cognitive resources to concentrate on higher-order concepts. This is supported by cognitive load theory.

Describes two studies that assessed decision-making skills using common cognitive errors and evaluated the impact of computer-based role-playing exercises on the development of these skills. Results with high school students, undergraduates, and earth science professionals are discussed which indicate that well-designed computer-based laboratories can positively impact higher-order cognitive skills. Contains 56 references. (LRW)

Spatial complexity impacts the resilience of river ecosystems by mediating processes that control the sources and sinks of sediment and organic material. Using four independent geochemical tracers and three morphometric indices, we show that downstream spatial gradients in stream power (Ω) predict storage of material in the channels and margins and/or floodplains. A field test in a 48 km2 watershed demonstrates that reaches with downstream decreases in Ω coincide with wider floodplains and elevated inventories of 137Cs, 210Pbex (ex--excess), and organic matter in locations of the -3 to 20 yr floodplain. In contrast, reaches with downstream increases in Ω coincide with narrower floodplains and decreased inventories of 137Cs, 210Pbex and organic matter. The occurrence of in-channel bedrock exposures and the activity of short-lived 7Be in within-channel sediments also correlate with downstream Ω gradients, demonstrating a link, over both short and long time scales, between within-channel processes and floodplain-forming processes. The combined geochemical and physical characteristics demonstrate the importance of downstream gradients in sediment transport, characterized by downstream changes in stream power rather than at-a-point stream power, in determining spatial complexity in carbon and sediment storage at intermediate scales (102 to 103 m) in river systems. [ABSTRACT FROM AUTHOR]