Canadian High Research Articles

Steady march toward greatness? Tracing the evolution of Canada’s international position

The Fathers of Confederation believed their creation would go on to one day stand at the front rank of international powers. Using cross-national economic data we can evaluate the extent to which such ambition was realized. This article finds that while Canada’s ascent up the global league tables has been rapid, so too has there been a ceiling as to just how high Canada can rise. Even more, with per-capita wealth now growing so rapidly in parts of the world previously consigned to penury, Canada’s international rank is likely to fall if only modestly so.

Response to Comment on Climate Change and Mercury Accumulation in Canadian High and Subarctic Lakes

ADVERTISEMENT RETURN TO ISSUEPREVCorrespondence/Rebut...Correspondence/RebuttalNEXTResponse to Comment on Climate Change and Mercury Accumulation in Canadian High and Subarctic LakesJane L. Kirk*†, Derek C. G. Muir†, Dermot Antoniades‡, Marianne S. V. Douglas§, Marlene S. Evans∥, Togwell A. Jackson†, Hedy Kling⊥, Scott Lamoureux#, Darlene S. S. Lim▽, Reinhard Pienitz‡, John P. Smol○, Kailey Stewart#, Xiaowa Wang†, and Fan Yang†View Author Information† Aquatic Ecosystem Protection Research Division, Environment Canada, Burlington, ON, Canada L7R 4A6‡ Centre d'études nordiques, Université Laval, Quebec, QC, Canada GIV 0A6§ Canadian Circumpolar Institute, University of Alberta, Edmonton, AB, Canada T6G 1K8∥ Aquatic Ecosystem Protection Research Division, Environment Canada, Saskatoon, SK, Canada S7N 3H5⊥ Algal Taxonomy and Ecology, Winnipeg, MB, Canada R3T 2 × 8# Department of Geography, Queen’s University, Kingston, ON, Canada K7L 3N6▽ SETI Institute, Mountain View, CA, United States 94043-2172○ Department of Biology, Queen’s University, Kingston, ON, Canada K7L 3N6Phone: (905) 336-4712; fax: (905) 336-6430; e-mail: [email protected]Cite this: Environ. Sci. Technol. 2011, 45, 15, 6705–6706Publication Date (Web):July 8, 2011Publication History Published online8 July 2011Published inissue 1 August 2011https://doi.org/10.1021/es202053cCopyright © 2011 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views576Altmetric-Citations9LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (659 KB) Get e-AlertsSUBJECTS:Calibration,Deposition,Geological materials,Mercury,Plants Get e-Alerts

Comment on Climate Change and Mercury Accumulation in Canadian High and Subarctic Lakes

Comment on Climate Change and Mercury Accumulation in Canadian High and Subarctic Lakes

Climate Change and Mercury Accumulation in Canadian High and Subarctic Lakes

Mercury (Hg) profiles were compared to profiles of climate indicators including microfossil remains and algal-derived or S2 carbon (C) in dated sediment cores from 14 lakes spanning latitudinal and longitudinal gradients across the Canadian high and subarctic. Hg fluxes increased postindustrialization (post-∼1850) in 11 of these lakes (postindustrialization Hg fluxes (ΔHgF(F)) = 2-24 μg m(-2) y(-1)). Correction of HgF(F) for catchment contributions demonstrated that Hg deposition originating from catchment-independent factors, such as atmospheric deposition, increased since industrialization in all 14 lakes. Several of these lakes also showed postindustrial shifts in algal assemblages consistent with climate-induced changes. Eleven lakes showed post-1850s increases in S2F(F), suggesting that lake primary productivity has recently increased in the majority of our sites (ΔS2F(F) = 0.1-4 g m(-2) y(-1)). Other studies have interpreted significant relationships between Hg:S2 concentrations in Arctic sediment as support for the algal scavenging hypothesis, which postulates that Hg fluxes to Arctic sediments are largely driven by S2. However, in six of our lakes we observed no Hg:S2 relationship, and in one lake a significant negative Hg:S2 relationship was observed due to increased Hg and decreased S2 C deposition during the postindustrialization period. In six of the seven lakes where a significant positive Hg:S2 relationship was observed, algal assemblages either did not change through time or the timing of the shifts did not correspond to changes in Hg deposition. Our results demonstrate that, although Arctic lakes are experiencing a myriad of changes, including increased Hg and S2 deposition or changing algal assemblages, increased lake primary productivity does not appear to be driving changes in Hg fluxes to sediments.

Climate Change and Mercury Accumulation in Canadian High and Subarctic Lakes

Mercury (Hg) profiles were compared to profiles of climate indicators including microfossil remains and algal-derived or S2 carbon (C) in dated sediment cores from 14 lakes spanning latitudinal and longitudinal gradients across the Canadian high and subarctic. Hg fluxes increased postindustrialization (post-∼1850) in 11 of these lakes (postindustrialization Hg fluxes (ΔHgF(F)) = 2-24 μg m(-2) y(-1)). Correction of HgF(F) for catchment contributions demonstrated that Hg deposition originating from catchment-independent factors, such as atmospheric deposition, increased since industrialization in all 14 lakes. Several of these lakes also showed postindustrial shifts in algal assemblages consistent with climate-induced changes. Eleven lakes showed post-1850s increases in S2F(F), suggesting that lake primary productivity has recently increased in the majority of our sites (ΔS2F(F) = 0.1-4 g m(-2) y(-1)). Other studies have interpreted significant relationships between Hg:S2 concentrations in Arctic sediment as support for the algal scavenging hypothesis, which postulates that Hg fluxes to Arctic sediments are largely driven by S2. However, in six of our lakes we observed no Hg:S2 relationship, and in one lake a significant negative Hg:S2 relationship was observed due to increased Hg and decreased S2 C deposition during the postindustrialization period. In six of the seven lakes where a significant positive Hg:S2 relationship was observed, algal assemblages either did not change through time or the timing of the shifts did not correspond to changes in Hg deposition. Our results demonstrate that, although Arctic lakes are experiencing a myriad of changes, including increased Hg and S2 deposition or changing algal assemblages, increased lake primary productivity does not appear to be driving changes in Hg fluxes to sediments.

Manual synoptic climate classification for the east coast of New England (USA) with an application to PM2.5 concentration

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 28:143-153 (2005) - doi:10.3354/cr028143 Manual synoptic climate classification for the east coast of New England (USA) with an application to PM2.5 concentration Barry D. Keim1,*, Loren David Meeker2, John F. Slater3 1Department of Geography and Anthropology, Louisiana State University, 327E Howe-Russell Science Complex, Baton Rouge, Louisiana 70803, USA2Climate Change Research Center, University of New Hampshire, 56 College Road, Durham, New Hampshire 03824, USA3Division of Engineering, Math, and Science, Daniel Webster College, 20 University Drive, Nashua, New Hampshire 03063, USA *Email: keim@lsu.edu ABSTRACT: This study presents a manual synoptic climate classification for the East Coast of New England with an application to regional pollution. New England weather was classified into 9 all-inclusive weather types: Canadian High, Modified High, Gulf of Maine Return, New England High, Atlantic Return, Frontal Atlantic Return, Frontal Overrunning–Continental, Frontal Overrunning–Marine, and Tropical Disturbance. Canadian High and Modified High weather are the dominant weather patterns at Boston, Massachusetts, while Tropical Disturbance, Gulf of Maine Return, and New England High weather types are the least frequent. Properties of the weather types were determined at 07:00 h Local Standard Time (LST) each day in Boston. The coldest and driest weather type is the Canadian High, while the hottest, most humid weather is generated by Frontal Atlantic Return. The synoptic weather classification system, applied to airborne fine particle mass concentrations with an aerodynamic diameter ≤2.5 µm (PM2.5), showed significant differences in concentrations between weather types: transport from the north and northwest had low PM2.5, while transport from the south and southwest had high PM2.5 concentrations. This climate classification system also has potential applications ranging from studies of insect migration to analyses of climate change. KEY WORDS: synoptic climatology · New England · USA · Boston · weather types · applied climatology · PM2.5 Full article in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 28, No. 2. Online publication date: March 16, 2005 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2005 Inter-Research.