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A comprehensive database of paleoclimate records is needed to place recent warming into the longer-term context of natural climate variability. We present a global compilation of quality-controlled, published, temperature-sensitive proxy records extending back 12,000 years through the Holocene. Data were compiled from 679 sites where time series cover at least 4000 years, are resolved at sub-millennial scale (median spacing of 400 years or finer) and have at least one age control point every 3000 years, with cut-off values slackened in data-sparse regions. The data derive from lake sediment (51%), marine sediment (31%), peat (11%), glacier ice (3%), and other natural archives. The database contains 1319 records, including 157 from the Southern Hemisphere. The multi-proxy database comprises paleotemperature time series based on ecological assemblages, as well as biophysical and geochemical indicators that reflect mean annual or seasonal temperatures, as encoded in the database. This database can be used to reconstruct the spatiotemporal evolution of Holocene temperature at global to regional scales, and is publicly available in Linked Paleo Data (LiPD) format., Measurement(s)climateTechnology Type(s)digital curationFactor Type(s)temporal interval • geographic location • proxy typeSample Characteristic - Environmentclimate systemSample Characteristic - LocationEarth (planet) Machine-accessible metadata file describing the reported data: https://www.ncdc.noaa.gov/paleo/study/27330

The geochemistry of lake sediments was used to identify anthropogenic factors influencing aquatic ecosystems of sub-alpine lakes in the western United States during the past century. Sediment cores were recovered from six high-elevation lakes in the central Great Basin of the United States. The proxies utilized to examine the degree of recent anthropogenic environmental change include spheroidal carbonaceous particle (SCP), mercury (Hg), and sediment organic content estimated using loss-on-ignition. Chronologies for the sediment cores, developed using 210Pb, indicate the cores span the twentieth century. Mercury flux varied between lakes but all exhibited increasing fluxes during the mid-twentieth century. The mean ratio of modern (post-A.D. 1985) to preindustrial (pre-A.D. 1880) Hg flux was 5.2, which is comparable to the results from previous studies conducted in western North America. Peak SCP flux for all lakes occurred between approximately A.D. 1940 and A.D. 1970, after which time the SCP flux was greatly reduced. The reduction in SCP input is likely due to better controls on combustion sources. Measured Hg concentrations and calculated sedimentation rates suggest atmospheric Hg flux increased in the early 1900s, from A.D. 1920 to A.D. 1990, and at present. Atmospheric deposition is the primary source of the anthropogenic inputs of Hg and SCPs to these high elevation lakes. The input of SCPs, which is largely driven by regional sources, has declined with the implementation of national pollution control regulations. Mercury deposition in the Great Basin has most likely been influenced more by regional inputs.