33 research outputs found

    The DOE E3SM Coupled Model Version 1: Overview and Evaluation at Standard Resolution

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    This work documents the first version of the U.S. Department of Energy (DOE) new Energy Exascale Earth System Model (E3SMv1). We focus on the standard resolution of the fully coupled physical model designed to address DOE mission-relevant water cycle questions. Its components include atmosphere and land (110-km grid spacing), ocean and sea ice (60 km in the midlatitudes and 30 km at the equator and poles), and river transport (55 km) models. This base configuration will also serve as a foundation for additional configurations exploring higher horizontal resolution as well as augmented capabilities in the form of biogeochemistry and cryosphere configurations. The performance of E3SMv1 is evaluated by means of a standard set of Coupled Model Intercomparison Project Phase 6 (CMIP6) Diagnosis, Evaluation, and Characterization of Klima simulations consisting of a long preindustrial control, historical simulations (ensembles of fully coupled and prescribed SSTs) as well as idealized CO2 forcing simulations. The model performs well overall with biases typical of other CMIP-class models, although the simulated Atlantic Meridional Overturning Circulation is weaker than many CMIP-class models. While the E3SMv1 historical ensemble captures the bulk of the observed warming between preindustrial (1850) and present day, the trajectory of the warming diverges from observations in the second half of the twentieth century with a period of delayed warming followed by an excessive warming trend. Using a two-layer energy balance model, we attribute this divergence to the model’s strong aerosol-related effective radiative forcing (ERFari+aci = -1.65 W/m2) and high equilibrium climate sensitivity (ECS = 5.3 K).Plain Language SummaryThe U.S. Department of Energy funded the development of a new state-of-the-art Earth system model for research and applications relevant to its mission. The Energy Exascale Earth System Model version 1 (E3SMv1) consists of five interacting components for the global atmosphere, land surface, ocean, sea ice, and rivers. Three of these components (ocean, sea ice, and river) are new and have not been coupled into an Earth system model previously. The atmosphere and land surface components were created by extending existing components part of the Community Earth System Model, Version 1. E3SMv1’s capabilities are demonstrated by performing a set of standardized simulation experiments described by the Coupled Model Intercomparison Project Phase 6 (CMIP6) Diagnosis, Evaluation, and Characterization of Klima protocol at standard horizontal spatial resolution of approximately 1° latitude and longitude. The model reproduces global and regional climate features well compared to observations. Simulated warming between 1850 and 2015 matches observations, but the model is too cold by about 0.5 °C between 1960 and 1990 and later warms at a rate greater than observed. A thermodynamic analysis of the model’s response to greenhouse gas and aerosol radiative affects may explain the reasons for the discrepancy.Key PointsThis work documents E3SMv1, the first version of the U.S. DOE Energy Exascale Earth System ModelThe performance of E3SMv1 is documented with a set of standard CMIP6 DECK and historical simulations comprising nearly 3,000 yearsE3SMv1 has a high equilibrium climate sensitivity (5.3 K) and strong aerosol-related effective radiative forcing (-1.65 W/m2)Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151288/1/jame20860_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151288/2/jame20860.pd

    Environmental variability supports chimpanzee behavioural diversity.

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    Funder: Max-Planck-Gesellschaft (Max Planck Society); doi: https://doi.org/10.13039/501100004189Funder: Heinz L. Krekeler FoundationLarge brains and behavioural innovation are positively correlated, species-specific traits, associated with the behavioural flexibility animals need for adapting to seasonal and unpredictable habitats. Similar ecological challenges would have been important drivers throughout human evolution. However, studies examining the influence of environmental variability on within-species behavioural diversity are lacking despite the critical assumption that population diversification precedes genetic divergence and speciation. Here, using a dataset of 144 wild chimpanzee (Pan troglodytes) communities, we show that chimpanzees exhibit greater behavioural diversity in environments with more variability - in both recent and historical timescales. Notably, distance from Pleistocene forest refugia is associated with the presence of a larger number of behavioural traits, including both tool and non-tool use behaviours. Since more than half of the behaviours investigated are also likely to be cultural, we suggest that environmental variability was a critical evolutionary force promoting the behavioural, as well as cultural diversification of great apes

    The Fox/Forkhead transcription factor family of the hemichordate Saccoglossus kowalevskii

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    Outcome-Reporting Bias in Education Research

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    Outcome reporting bias occurs when primary studies do not include information about all outcomes measured in a study. When studies omit findings on important measures, efforts to synthesize the research using systematic review techniques will be biased and interpretations of individual studies will be incomplete. Outcome reporting bias has been well-documented in medicine, and has been shown to lead to inaccurate assessments of the effects of medical treatments and, in some cases, to omission of reports of harms. This study examines outcome reporting bias in educational research by comparing the reports of educational interventions from dissertations to their published versions. We find that non-significant outcomes were 30% more likely to be omitted from a published study than statistically significant ones

    An Architectural Overview of Hydroshare, A Next-Generation Hydrologic Information System

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    HydroShare is an online, open-source, collaborative system being developed for sharing hydrologic data and models as part of the NSF’s Software Infrastructure for Sustained Innovation (SI2) program. The goal of HydroShare is to enable scientists to easily discover and access hydrologic data and models, retrieve them to their desktop, or perform analyses in a distributed computing environment that may include grid, cloud, or high performance computing. Scientists may also publish outcomes (data, results or models) into HydroShare, using the system as a collaboration platform for sharing data, models, and analyses. HydroShare involves a large distributed software development effort requiring collaboration between domain scientists, software engineers, and software developers across eight U.S. universities, RENCI, and CUAHSI. HydroShare expands the data sharing capabilities of the Hydrologic Information System of the Consortium of Universities for the Advancement of Hydrologic Sciences, Inc. (CUAHSI): It broadens the classes of data accommodated, enables sharing of models and model components, and leverages social media functionality to enhance collaboration around hydrologic data and models. The HydroShare architecture is a stack of storage and computation, web services, and user applications. A content management system, Django+Mezzanine, provides user interface, search, social media functions, and services. A geospatial visualization and analysis component enables searching, visualizing, and analyzing geographic datasets. The integrated Rule-Oriented Data System (iRODS) is used to manage federated data content and perform rule-based background actions on data and model resources, including parsing to generate metadata catalog information and the distributed execution of models and workflows. A web browser is the main interface to HydroShare, however a web services applications programming interface (API) supports access through HydroDesktop and other hydrologic modeling systems, and the architecture separates the interface layer and services layer exposing all functionality through these web services. This presentation will describe key components of HydroShare and discuss how HydroShare is designedto enable better hydrologic science concomitant with sustainable open-source software practices
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