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This is an Accepted Manuscript of an article published by Taylor & Francis in Lake and Reservoir Management on 02 Jun 2023, available at https:// doi.org/10.1080/10402381.2023.2204061 Paleolimnological analyses of 3 lakes within the Trent-Severn Waterway (TSW) were analyzed 19 to evaluate the role of regional land-use practices (forestry and agriculture), climate change, and 20 landscape position on cultural eutrophication and lake response over the past ~200 years. Kawartha Lakes Stewards Association. Faculty yes

Supplemental material, sj-docx-1-anr-10.1177_20530196221149281 for The varved succession of Crawford Lake, Milton, Ontario, Canada as a candidate Global boundary Stratotype Section and Point for the Anthropocene series by Francine MG McCarthy, Timothy Patterson, Martin J Head, Nicholas L Riddick, Brian F Cumming, Paul B Hamilton, Michael FJ Pisaric, Cale Gushulak, Peter R Leavitt, Krysten M Lafond, Brendan Llew-Williams, Matthew Marshall, Autumn Heyde, Paul M Pilkington, Joshua Moraal, Joseph I Boyce, Nawaf A Nasser, Carling Walsh, Monica Garvie, Sarah Roberts, Neil L Rose, Andy B Cundy, Pawel Gaca, Andy Milton, Irka Hajdas, Carley A Crann, Arnoud Boom, Sarah A Finkelstein and John H McAndrews in The Anthropocene Review

© The Author(s) 2021. This article is distributed under the terms of the Creative Commons Attribution 4.0 Lficense (https://creativecommons.org/licenses/by/4.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage). Descriptions of regional climate expression require data from multiple lakes, yet little is known of how variation in records within morphometrically complex lakes may affect interpretations. In northeast Ontario (Canada), this issue was addressed using records of pollen, pigments, and diatoms in three sediment cores from two small boreal lakes spanning the last ~6000 years. Pollen analysis suggested warm conditions between ~6000 and ~4000 cal yr BP, coherent with previous assessments from boreal eastern Ontario and western Quebec. Analysis of phototrophic communities from fossil pigments and diatom valves suggested relatively eutrophic conditions with lower lake-levels during this interval. Generalized additive model trends identified significant regional changes in pollen assemblages and declines in pigment concentrations after ~4000 cal yr BP consistent with cooler and wetter climate conditions that resulted in regional lake oligotrophication and increased lake levels during the late-Holocene. Despite contemporaneous changes in pollen and pigment biomarkers across lakes, cores collected from adjacent basins of the same lake (Green Lake) did not show similar trends in fossil pigments likely reflecting preferential deposition of clay-rich allochthonous material in the deeper central basin and suggesting that regional signals in climate may be complicated by lake- or basin-specific catchment processes. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This project was funded by NSERC Discovery grants to PRL and BFC, an NSERC PGS-D scholarship to CACG, and with support from The W. Garfield Weston Foundation Fellowship Program, a program of the Wildlife Conservation Society Canada funded by The W. Garfield Weston Foundation. Pigment analysis was supported by the Canada Foundation for Innovation and Province of Saskatchewan. Faculty yes

Holocene climate reconstructions are useful for understanding the diverse features and spatial heterogeneity of past and future climate change. Here we present a database of western North American Holocene paleoclimate records. The database gathers paleoclimate time series from 184 terrestrial and marine sites, including 381 individual proxy records. The records span at least 4000 of the last 12 000 years (median duration of 10 725 years) and have been screened for resolution, chronologic control, and climate sensitivity. Records were included that reflect temperature, hydroclimate, or circulation features. The database is shared in the machine readable Linked Paleo Data (LiPD) format and includes geochronologic data for generating site-level time-uncertain ensembles. This publicly accessible and curated collection of proxy paleoclimate records will have wide research applications, including, for example, investigations of the primary features of ocean–atmospheric circulation along the eastern margin of the North Pacific and the latitudinal response of climate to orbital changes. The database is available for download at https://doi.org/10.6084/m9.figshare.12863843.v1 (Routson and McKay, 2020).

Supplemental material, sj-pdf-2-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, sj-docx-1-anr-10.1177_20530196211046036 for Siliceous algae response to the “Great Acceleration” of the mid-20th century in Crawford Lake (Ontario, Canada): A potential candidate for the Anthropocene GSSP by Cale AC Gushulak, Matthew Marshall, Brian F Cumming, Brendan Llew-Williams, R Timothy Patterson and Francine MG McCarthy in The Anthropocene Review

Supplemental material, sj-pdf-2-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, sj-pdf-3-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, sj-pdf-3-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, sj-pdf-1-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, sj-pdf-1-hol-10.1177_09596836211025972 for Basin-specific records of lake oligotrophication during the middle-to-late Holocene in boreal northeast Ontario, Canada by Cale AC Gushulak, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, SFigure_3_Pollen_Concentration for Complex responses of phototrophic communities to climate warming during the Holocene of northeastern Ontario, Canada by Brett G Elmslie, Cale AC Gushulak, Maxime P Boreux, Scott F Lamoureux, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, SFigure_1_Gamma_dating_curves for Complex responses of phototrophic communities to climate warming during the Holocene of northeastern Ontario, Canada by Brett G Elmslie, Cale AC Gushulak, Maxime P Boreux, Scott F Lamoureux, Peter R Leavitt and Brian F Cumming in The Holocene

Supplemental material, SFigure_2_Bstick_model for Complex responses of phototrophic communities to climate warming during the Holocene of northeastern Ontario, Canada by Brett G Elmslie, Cale AC Gushulak, Maxime P Boreux, Scott F Lamoureux, Peter R Leavitt and Brian F Cumming in The Holocene

In the version of this Review Article originally published, ref. 10 was mistakenly cited instead of ref. 107 at the end of the sentence: “This complexity of residual ice cover makes it likely that HTM warming was regional, rather than global, and its peak warmth thus had different timing in different locations.” In addition, for ref. 108, Scientific Reports was incorrectly given as the publication name; it should have been Scientific Data. These errors have now been corrected in the online versions.

In the version of this Review Article originally published, ref. 10 was mistakenly cited instead of ref. 107 at the end of the sentence: “This complexity of residual ice cover makes it likely that HTM warming was regional, rather than global, and its peak warmth thus had different timing in different locations.” In addition, for ref. 108, Scientific Reports was incorrectly given as the publication name; it should have been Scientific Data. These errors have now been corrected in the online versions.

Over the past 3.5 million years, there have been several intervals when climate conditions were warmer than during the pre-industrial Holocene. Although past intervals of warming were forced differently than future anthropogenic change, such periods can provide insights into potential future climate impacts and ecosystem feedbacks, especially over centennial-to-millennial timescales that are often not covered by climate model simulations. Our observation-based synthesis of the understanding of past intervals with temperatures within the range of projected future warming suggests that there is a low risk of runaway greenhouse gas feedbacks for global warming of no more than 2 °C. However, substantial regional environmental impacts can occur. A global average warming of 1–2 °C with strong polar amplification has, in the past, been accompanied by significant shifts in climate zones and the spatial distribution of land and ocean ecosystems. Sustained warming at this level has also led to substantial reductions of the Greenland and Antarctic ice sheets, with sea-level increases of at least several metres on millennial timescales. Comparison of palaeo observations with climate model results suggests that, due to the lack of certain feedback processes, model-based climate projections may underestimate long-term warming in response to future radiative forcing by as much as a factor of two, and thus may also underestimate centennial-to-millennial-scale sea-level rise.