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The call to improve undergraduate science, technology, engineering, and mathematics (STEM) education can be answered by undergraduate faculty modifying their course content and teaching methods to generate better student outcomes. The National Geoscience Faculty Survey--administered in 2004, 2009, 2012, and 2016--provides evidence that the vast majority of geoscience faculty recently modified their course content in a variety of ways, and about half recently adjusted their teaching methods toward more student-centered approaches. Respondents from across many different subgroups (e.g., institution type, position, and class type) are equally likely to modify content, perhaps reflecting the importance of current events, societal issues, and recent research findings to undergraduate geoscience education. In contrast, whether a respondent modified his or her teaching methods in the last two years varies strongly across subgroups. Two predictors of whether respondents modified their teaching methods is whether they also modified content, with respondents who changed their course content almost twice as likely to have also changed their teaching methods and how frequently they speak to colleagues about teaching, with more frequent discussion correlated with a higher percentage of faculty changing teaching methods. A major inhibitor to making course modifications is time constraints, and the promotion and tenure process may play a role in inhibiting change. The results indicate that the geoscience community approach of embedding discussions of teaching methods within workshops, webinars, and modules that primarily focus on teaching specific content may be an effective means of improving STEM education more broadly.

Late Cenozoic stream incision and basin excavation have strongly influenced the modern Rocky Mountain landscape, but constraints on the timing and rates of erosion are limited. The geology of the Powder River basin provides an unusually good opportunity to address spatial and temporal patterns of stream incision. Numerous coal seams in the Paleocene Fort Union and Eocene Wasatch Formations within the basin have burned during late Cenozoic incision, as coal was exposed to dry and oxygen-rich near-surface conditions. The topography of this region is dominated by hills capped with clinker, sedimentary rocks metamorphosed by burning of underlying coal beds. We use (U-Th)/He ages of clinker to determine times of relatively rapid erosion, with the assumption that coal must be near Earth's surface to burn. Ages of 55 in situ samples range from 0.007 to 1.1 Ma. Clinker preferentially formed during times in which eccentricity of the Earth's orbit was high, times that typically but not always correlate with interglacial periods. Our data therefore suggest that rates of landscape evolution in this region are affected by climate fluctuations. Because the clinker ages correlate better with eccentricity time series than with an oxygen isotope record of global ice volume, we hypothesize that variations in solar insolation modulated by eccentricity have a larger impact on rates of landscape evolution in this region than do glacial-interglacial cycles.

Abstract: Glaciated alpine landscapes are sensitive to changes in climate. Shifts in temperature and precipitation can cause significant changes to glacier size and terminus position, the production and delivery of organic mass, and in the hydrologic energy related to the transport of water and sediment through proglacial environments. A sediment core representing a 12,900-yr record collected from Swiftcurrent Lake, located on the eastern side of Glacier National Park, Montana, was analyzed to assess variability in Holocene and latest Pleistocene environment. The spectral signature of total organic carbon content (%TOC) since ~7.6ka matches that of solar forcing over 70–500yr timescales. Periodic inputs of dolomite to the lake reflect an increased footprint of Grinnell Glacier, and occur during periods when sediment sinks are reduced, glacial erosion is increased, and hydrologic energy is increased. Grain size, carbon/nitrogen (C/N) ratios, and %TOC broadly define the termination of the Younger Dryas chronozone at Swiftcurrent Lake, as well as major Holocene climate transitions. Variability in core parameters is linked to other records of temperature and aridity in the northern Rocky Mountains over the late Pleistocene and Holocene. [ABSTRACT FROM AUTHOR]