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The paleogeosciences are becoming more and more interdisciplinary, and studies increasingly rely on large collections of data derived from multiple data repositories. Integrating diverse datasets from multiple sources into complex workflows increases the challenge of creating reproducible and open science, as data formats and tools are often noninteroperable, requiring manual manipulation of data into standardized formats, resulting in a disconnect in data provenance and confounding reproducibility. Here we present a notebook that demonstrates how the Linked PaleoData (LiPD) framework is used as an interchange format to allow data from multiple data sources to be integrated in a complex workflow using emerging packages in R for geochronological uncertainty quantification and abrupt change detection. Specifically, in this notebook, we use the neotoma2 and lipdR packages to access paleoecological data from the Neotoma Database, and paleoclimate data from compilations hosted on Lipdverse. Age uncertainties for datasets from both sources are then quantified using the geoChronR package, and those data, and their associated age uncertainties, are then investigated for abrupt changes using the actR package, with accompanying visualizations. The result is an integrated, reproducible workflow in R that demonstrates how this complex series of multisource data integration, analysis and visualization can be integrated into an efficient, open scientific narrative. 

Abstract. In 2013, the Intergovernmental Panel on Climate Changeconcluded that Northern Hemisphere temperatures had reached levelsunprecedented in at least 1400 years. The 2021 report now sees global meantemperatures rising to levels unprecedented in over 100 000 years. ThisTechnical Note briefly explains the reasons behind this major change.Namely, the new assessment reflects additional global warming that occurredbetween the two reports and improved paleotemperature reconstructions thatextend further back in time. In addition to past and recent warming, theconclusion also considers multi-century future warming, which therebyenables a direct comparison with paleotemperature reconstructions onmulti-century time scales. 

Global vegetation over the past 18,000 years has been transformed first by the climate changes that accompanied the last deglaciation and again by increasing human pressures; however, the magnitude and patterns of rates of vegetation change are poorly understood globally. Using a compilation of 1181 fossil pollen sequences and newly developed statistical methods, we detect a worldwide acceleration in the rates of vegetation compositional change beginning between 4.6 and 2.9 thousand years ago that is globally unprecedented over the past 18,000 years in both magnitude and extent. Late Holocene rates of change equal or exceed the deglacial rates for all continents, which suggests that the scale of human effects on terrestrial ecosystems exceeds even the climate-driven transformations of the last deglaciation. The acceleration of biodiversity change demonstrated in ecological datasets from the past century began millennia ago.