A5064915275- Geology and Paleoclimatology Research
- Climate change and permafrost
- Tree-ring climate responses
- Particle accelerators and beam dynamics
- Pleistocene-Era Hominins and Archaeology
- Archaeology and ancient environmental studies
- Superconducting Materials and Applications
- Particle Accelerators and Free-Electron Lasers
- Isotope Analysis in Ecology
- Geological Studies and Exploration
- Lichen and fungal ecology
- Geological formations and processes
- Cryospheric studies and observations
- Fire effects on ecosystems
- Peatlands and Wetlands Ecology
- Nuclear Physics and Applications
- Indigenous Studies and Ecology
- Spacecraft and Cryogenic Technologies
- Ecology and Vegetation Dynamics Studies
- Gyrotron and Vacuum Electronics Research
- Methane Hydrates and Related Phenomena
- Species Distribution and Climate Change
- Climate variability and models
- Diatoms and Algae Research
- Landslides and related hazards
University of Ottawa
2015-2024
Uppsala University
1990-2021
Master's College
2021
University of Toronto
2021
Toronto Metropolitan University
2021
Applied Mathematics (United States)
2021
Rzeszów University of Technology
2019
Ecological Society of America
2018
Wilfrid Laurier University
2018
Carleton University
2002-2016
A compilation of paleoclimate records from lake sediments, trees, glaciers, and marine sediments provides a view circum-Arctic environmental variability over the last 400 years. From 1840 to mid-20th century, Arctic warmed highest temperatures in four centuries. This warming ended Little Ice Age has caused retreats melting permafrost sea ice, alteration terrestrial ecosystems. Although warming, particularly after 1920, was likely by increases atmospheric trace gases, initiation mid-19th...
Subfossil pollen and plant macrofossil data derived from 14C-dated sediment profiles can provide quantitative information on glacial interglacial climates. The allow climate variables related to growing-season warmth, winter cold, plant-available moisture be reconstructed. Continental-scale reconstructions have been made for the mid-Holocene (MH, around 6 ka) Last Glacial Maximum (LGM, 21 ka), allowing comparison with palaeoclimate simulations currently being carried out as part of fifth...
The temperature history of the first millennium C.E. is sparsely documented, especially in Arctic. We present a synthesis decadally resolved proxy records from poleward 60 degrees N covering past 2000 years, which indicates that pervasive cooling progress years ago continued through Middle Ages and into Little Ice Age. A 2000-year transient climate simulation with Community Climate System Model shows same sensitivity to changes insolation as does our reconstruction, supporting inference this...
Abstract Reproducible climate reconstructions of the Common Era (1 CE to present) are key placing industrial-era warming into context natural climatic variability. Here we present a community-sourced database temperature-sensitive proxy records from PAGES2k initiative. The gathers 692 648 locations, including all continental regions and major ocean basins. trees, ice, sediment, corals, speleothems, documentary evidence, other archives. They range in length 50 2000 years, with median 547...
Fossil pollen records are well-established indicators of past vegetation changes. The prevalence across environmental settings including lakes, wetlands, and marine sediments, has made palynology one the most ubiquitous valuable tools for studying climatic change globally decades. A complementary research focus been development statistical techniques to derive quantitative estimates conditions from assemblages. This paper reviews commonly used their rationale seeks provide a resource...
A comprehensive database of paleoclimate records is needed to place recent warming into the longer-term context natural climate variability. We present a global compilation quality-controlled, published, temperature-sensitive proxy extending back 12,000 years through Holocene. Data were compiled from 679 sites where time series cover at least 4000 years, are resolved sub-millennial scale (median spacing 400 or finer) and have one age control point every 3000 with cut-off values slackened in...
A unified scheme to assign pollen samples vegetation types was used reconstruct patterns north of 55°N at the last glacial maximum (LGM) and mid‐Holocene (6000 years B.P.). The data set assembled for this purpose represents a comprehensive compilation based on work many projects research groups. Five tundra (cushion forb tundra, graminoid prostrate dwarf‐shrub erect low‐ high‐shrub tundra) were distinguished mapped basis modern surface samples. tundra‐forest boundary distributions boreal...
A mean continental July temperature reconstruction based on pollen records from across North America quantifies variations of several timescales for the past 14,000 cal yr BP. In America, temperatures increased nearly 4°C during late glacial, reaching maximum values between 6000 and 3000 BP, after which decreased. Superimposed this orbital‐scale trend are millennial‐scale that appear coherent in structure frequency with high‐resolution ice, marine other terrestrial paleoclimate Holocene....
Abstract Regional paleoclimate reconstructions for northern Canada quantify Holocene climate variability on orbital and millennial time scales provide a context to better understand the current global warming. The are based available pollen diagrams from boreal low Arctic zones of use modern analog technique (MAT). Four regional document space–time evolution during Holocene. Highest summer winter temperatures anomalies found in central early Eastern was relatively cool Holocene, whereas...
Climatic changes during the late Quaternary have resulted in substantial, often abrupt, rearrangements of terrestrial ecosystems, but relationship between these environmental and prehistoric human culture population size remains unclear. Using a database archaeological radiocarbon dates alongside network paleoecological records (sedimentary pollen charcoal) paleoclimatic reconstructions, we show that periods cultural demographic change northeastern United States occurred at same times as...
This article provides a review and synthesis of scholarly knowledge Depression-era droughts on the North American Great Plains, time place known colloquially as Dust Bowl era or Dirty Thirties. Recent events, including 2008 financial crisis, severe in US corn belt, release popular documentary film, have spawned resurgence public interest Bowl. Events also proven recent years to be considerable scholars researching phenomena related global environmental change, atmospheric circulation,...
Well-dated pollen profiles from six sites Maine to Minnesota record vegetation changes indicative of summer temperature and annual precipitation variations over the past 2000 yr. Laminations in sediment provide accurate time control. Multiple regression techniques were used calculate calibration functions a spatial network modern climate data. When applied diagrams, these yielded estimates that show long-term trend toward lower temperature. Superimposed on this are short-term fluctuations...
Holocene temperature variations were reconstructed for the Canadian Arctic Archipelago and coastal Greenland using pollen data from 39 radiocarbon-dated lake sediment cores. Using modern analog technique, mean July temperatures estimated past 10.2 ka, regional averages computed. In western central Arctic, maximum found before 7 ka. eastern north east Greenland, between 8 5 in southern after 4 When combined with previously published reconstructions boreal Canada Beringia, climate history of...
Abstract. Reanalysis data show an increasing trend in Arctic precipitation over the 20th century, but changes are not homogenous across seasons or space. The observed hydroclimate expected to continue and possibly accelerate coming only affecting pan-Arctic natural ecosystems human activities, also lower latitudes through atmospheric ocean circulations. However, a lack of spatiotemporal observational makes reliable quantification change difficult, especially long-term context. To understand...
The distribution and abundance of Sphagnum spores in North America Eurasia are mapped for the past 21 ka. present‐day abundant corresponds closely to areas with peatland development, maximum between 630 1300 mm annual precipitation −2° 6°C mean air temperature. During Wisconsin glaciation, there were apparently not large America, except Alaska. High spore percentages found eastern during deglaciation. Major development occurred boreal after 9 ka was a southward movement high 5 western Great...