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Contribution: In this work-in-progress paper we describe the process of creating and validating a conceptual assessment in the field of sedimentology for undergraduate geoscience courses. The mechanism can aid future geoscience educators and researchers in the process of academic assessment development aligned with learning objectives in these courses. Background: Prior literature review supports the benefits of using active learning tools in STEM (Science, Technology, Engineering, and Mathematics) courses. This paper is part of a larger project to develop and incorporate research-based active learning software in sedimentology and other geoscience courses to improve grade point average (GPA) and time to graduation for Hispanic students at Texas A&M University. To evaluate the novel tool, we designed and validated the conceptual assessment instrument presented in this work. Research Question: What is the process to develop and validate a conceptual assessment for sedimentology? Methodology: This paper follows quantitative analysis and the assessment triangle approach and focuses on cognition, observation, and interpretation to design and evaluate the conceptual assessment. In the cognition element of the triangle, we explain the mechanism for creating the assessment instrument using students' learning objectives. The observation element explains the mechanism of data collection and the instrument revision. The interpretation element explains the results of the validation process using item response theory and reliability measures. We collected the conceptual assessment data from 17 participants enrolled in two courses where sedimentology topics are taught. Participants were geology majors in one of the courses and engineering majors in the other. Findings: The team developed a conceptual assessment that included eight multiple-choice (MCQ) and four open-ended response questions. The results of the design process described the conceptualization of questions and their validation. Also, the validity of created rubrics was established using inter-rater reliability measures, which showed good agreement between raters. Additionally, the results of the validation process indicated that the conceptual assessment was designed for students with average abilities. 

Hispanic student performance indicators are markedly different from students of other ethnicities, with Hispanic students consistently having lower GPAs at graduation. SedimentSketch application will be a visual, personalized, and dual language tool that will combine new curricular materials and sketch recognition algorithms to improve student learning through sketching exercises and automatic, instantaneous feedback. We are currently working on development of SedimentSketch software, and only control group data are being collected. We hypothesize that SedimentSketch can transform the higher-education geoscience curriculum for Hispanic Serving Institutions (HSI) by enabling geoscience students to interact with the material and receive helpful feedback outside of class and by cultivating a more inclusive learning environment. The goal of this project is to use SedimentSketch application to help close the gap between Hispanic and non-Hispanic students’ GPAs, situational interest in geoscience courses, and STEM career trajectories. 

The Antarctic Circumpolar Current (ACC) represents the world’s largest ocean-current system and affects global ocean circulation, climate and Antarctic ice-sheet stability^1–3. Today, ACC dynamics are controlled by atmospheric forcing, oceanic density gradients and eddy activity⁴. Whereas palaeoceanographic reconstructions exhibit regional heterogeneity in ACC position and strength over Pleistocene glacial–interglacial cycles^5–8, the long-term evolution of the ACC is poorly known. Here we document changes in ACC strength from sediment cores in the Pacific Southern Ocean. We find no linear long-term trend in ACC flow since 5.3 million years ago (Ma), in contrast to global cooling⁹and increasing global ice volume¹⁰. Instead, we observe a reversal on a million-year timescale, from increasing ACC strength during Pliocene global cooling to a subsequent decrease with further Early Pleistocene cooling. This shift in the ACC regime coincided with a Southern Ocean reconfiguration that altered the sensitivity of the ACC to atmospheric and oceanic forcings^11–13. We find ACC strength changes to be closely linked to 400,000-year eccentricity cycles, probably originating from modulation of precessional changes in the South Pacific jet stream linked to tropical Pacific temperature variability¹⁴. A persistent link between weaker ACC flow, equatorward-shifted opal deposition and reduced atmospheric CO₂during glacial periods first emerged during the Mid-Pleistocene Transition (MPT). The strongest ACC flow occurred during warmer-than-present intervals of the Plio-Pleistocene, providing evidence of potentially increasing ACC flow with future climate warming.