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The external drivers and internal controls of groundwater flow in the thawed “active layer” above permafrost are poorly constrained because they are dynamic and spatially variable. Understanding these controls is critical because groundwater can supply solutes such as dissolved organic matter to surface water bodies. We calculated steady‐state three‐dimensional suprapermafrost groundwater flow through the active layer using measurements of aquifer geometry, saturated thickness, and hydraulic properties collected from two major landscape types over time within a first‐order Arctic watershed. The depth position and thickness of the saturated zone is the dominant control of groundwater flow variability between sites and during different times of year. The effect of water table depth on groundwater flow dwarfs the effect of thaw depth. In landscapes with low land‐surface slopes (2–4%), a combination of higher water tables and thicker, permeable peat deposits cause relatively constant groundwater flows between the early and late thawed seasons. Landscapes with larger land‐surface slopes (4–10%) have both deeper water tables and thinner peat deposits; here the commonly observed permeability decrease with depth is more pronounced than in flatter areas, and groundwater flows decrease significantly between early and late summer as the water table drops. Groundwater flows are also affected by microtopographic features that retain groundwater that could otherwise be released as the active layer deepens. The dominant sources of groundwater, and thus dissolved organic matter, are likely wet, flatter regions with thick organic layers. This finding informs fluid flow and solute transport dynamics for the present and future Arctic. Groundwater flow in permafrost watersheds is potentially a key component of global carbon budgets because permafrost soil stores vast amounts of carbon that could be mobilized due to a warming climate and the corresponding increase in soil thaw. In addition to carrying carbon, groundwater can supply important nutrients and solutes to surface waters. However, we do not yet understand the factors that control groundwater flow in soils above permafrost because saturation changes rapidly and continuously, and soil hydraulic properties are largely unknown. We created measurement‐informed calculations of groundwater flow from areas of permafrost with different characteristics and found that soil types, which vary based on the slope of the land surface, are the most important control. Near‐surface soils were identical in hillslopes and valleys, whereas deeper soils in hillslopes allowed for less groundwater flow than in valleys. In early summer, when only the near‐surface soils were thawed, groundwater flows in the hillslopes and valley were similar. In late summer, when the deeper soil was thawed, groundwater flow in the valley remained high, but flow in the hillslope was negligible. Our observations also showed that small mounds on the land surface caused groundwater to be trapped behind underground ice dams. Detailed measurements of hydraulic head, hydraulic conductivity, and saturated thicknesses in active layers were made over time and spaceThree main soil layers consistently comprise the stratigraphy of the active layer across the studied Arctic watershedGroundwater flow depends most on the depth of the water table and the subsurface stratigraphy, which varies based on landscape type

The article informs that rural school educators are often isolated and have few opportunities to learn and low-performing rural schools faced with implementing significant reform efforts. It is mentioned that professional collaboration for evolving a community of expertise and service among teachers, built on collegial solidarity, feedback and collective responsibility. The article discusses the four B's framework professional learning including before, besides, beyond, and betwixt.

Groundwater flow regimes in the seasonally thawed soils in areas of continuous permafrost are relatively unknown despite their potential role in delivering water, carbon, and nutrients to streams. Using numerical groundwater flow models informed by observations from a headwater catchment in arctic Alaska, United States, we identify several mechanisms that result in substantial surface‐subsurface water exchanges across the land surface during downslope transport and create a primary control on dissolved organic carbon loading to streams and rivers. The models indicate that surface water flowing downslope has a substantial groundwater component due to rapid surface‐subsurface exchanges across a range of hydrologic states, from unsaturated to flooded. Field‐based measurements corroborate the high groundwater contributions, and river dissolved organic carbon concentrations are similar to that of groundwater across large discharge ranges. The persistence of these groundwater contributions in arctic watersheds will influence carbon export to rivers as thaw depth increases in a warmer climate. This paper shows that groundwater processes have a dominant role in controlling carbon export from the land to streams in permafrost terrain. We use hydrologic models to show that microtopography on the land surface drives the rapid exchange of overland flow with shallow groundwater. In other words, the water (porpoises) from just above to just below the land surface and back again as it moves downslope. Combined with the rapid leaching of organic carbon from soils, these findings provide a mechanistic explanation for two decades of measurements showing high concentrations of carbon in soils and streams during high flow conditions for both spring snowmelt and summer storms. During drier time periods, groundwater contributions from the thin thawed layer make up the flow in streams and keep dissolved organic carbon concentrations high. The persistence of these groundwater contributions in arctic watersheds will influence carbon export to rivers as thaw depth increases in a warmer climate. Surface‐subsurface water exchanges across the landscape control solute export from watershedsOverland flow water contains substantial amounts of groundwaterConstant stream DOC over large flow ranges and varied active layer thaw corroborate the role of surface‐subsurface exchanges in DOC export

Purpose: This Commentary is a review and critique of arguments that oppose the desirability and impact of professional collaboration in education. The purpose of this paper is to analyze two recent high-profile reviews of professional development and collaboration. The analysis is informed by a historical typology of five phases of professional collaboration in theory and practice. Design/methodology/approach: The Commentary reviews and summarizes selected key texts that represent different phases in the development of advocacy for and research concerning the emergence of professional collaboration. It then critiques the methodology, findings, and recommendations of two key critiques of professional collaboration and development that have been widely disseminated for educators and policymakers. Findings: Contrary to the views of its opponents, professional collaboration as a whole has a record of indirect, long term, yet clear and positive effects on teachers and students. Particular kinds of professional collaboration can vary a great deal in quality and impact, however. Short-term collaborative interventions, such as data teams, are often dependent for their success on the prior existence of deeper cultures and processes. These processes and cultures characterize high-performing systems globally. Advocacy for competitive alternatives is based on insufficient evidence. Originality/value: Although advocacy for more competition in public school systems is common, high-profile critiques of professional collaboration are relatively new. This paper engages with these critiques from a broader historical perspective, and finds they have serious flaws of reasoning and methodology. Thus far, the critiques provide insufficient warrant for moves toward more competitive systems of schooling and teaching.

Warming and thawing in the Arctic are promoting biogeochemical processing and hydrologic transport in carbon‐rich permafrost and soils that transfer carbon to surface waters or the atmosphere. Hydrologic and biogeochemical impacts of thawing are challenging to predict with sparse information on arctic soil hydraulic and thermal properties. We developed empirical and statistical models of soil properties for three main strata in the shallow, seasonally thawed soils above permafrost in a study area of ~7,500 km2in Alaska. The models show that soil vertical stratification and hydraulic properties are predictable based on vegetation cover and slope. We also show that the distinct hydraulic and thermal properties of each soil stratum can be predicted solely from bulk density. These findings fill the gap for a sparsely mapped region of the Arctic and enable regional interpolation of soil properties critical for determining future hydrologic responses and the fate of carbon in thawing permafrost. Arctic permafrost holds about as much carbon as currently present in the atmosphere. Rapid warming in the Arctic has raised concerns that this stored carbon could thaw and get released into the atmosphere, which would substantially amplify global warming. The rate of this carbon release to the atmosphere depends on the rate of environmental processes such as microbial respiration and heat and groundwater flow. The soil properties controlling these processes are currently unknown across most of the Arctic, making predictions of the processes highly uncertain at larger scales. This study uses hundreds of measurements of soil properties across an area of land larger than Delaware to show that soil properties in the foothills of the Brooks Range in northern Alaska are predictable if the landscape slope, dominant vegetation type, and local topography are known. This study provides a base for calculating transport processes related to soil carbon in the Arctic. Thermal and hydraulic properties of 265 permafrost soil samples from across the Arctic foothills of Alaska were measuredDifferent soil strata (acrotelm, catotelm, and mineral soil) have consistent properties and thickness over hundreds of kilometersThe soil properties are strongly related to vegetation and surface slope and can be independently predicted from soil bulk density