Alexander P Wolfe
Dados Biográficos
| ID | 1542697 |
|---|---|
| NOME | Alexander P Wolfe |
| PRENOMES | Alexander P |
| SOBRENOME | Wolfe |
| ASSINATURA | WOLFE A P |
| AFILIAÇÕES | University of Alberta |
| VERIFICADO | Não |
| TOTAL DE OBRAS | 17 |
| TOTAL DE CITAÇÕES | 486 |
| TOTAL COMO AUTOR | 17 |
| TOTAL COMO EDITOR | 0 |
| PRIMEIRO ANO DE PUBLICAÇÃO | 1996 |
| ANO MAIS RECENTE DE PUBLICAÇÃO | 2017 |
| ÍNDICE H | 7 |
The Working Group on the Anthropocene
Scale and diversity of the physical technosphere
We assess the scale and extent of the physical technosphere, defined here as the summed material output of the contemporary human enterprise. It includes active urban, agricultural and marine components, used to sustain energy and material flow for current human life, and a growing residue layer, currently only in small part recycled back into the active component. Preliminary estimates suggest a technosphere mass of approximately 30 trillion ton…
The Anthropocene is functionally and stratigraphically distinct from the Holocene
Evidence of an Anthropocene epoch Humans are undoubtedly altering many geological processes on Earth—and have been for some time. But what is the stratigraphic evidence for officially distinguishing this new human-dominated time period, termed the “Anthropocene,” from the preceding Holocene epoch? Waters et al. review climatic, biological, and geochemical signatures of human activity in sediments and ice cores. Combined with deposits of new mater…
Re-conceptualizing the Anthropocene
Since it was first proposed in 2000, the concept of the Anthropocene has evolved in breadth and diversely. The concept encapsulates the new and unprecedented planetary-scale changes resulting from societal transformations and has brought to the fore the social drivers of global change. The concept has revealed tensions between generalized interpretations of humanity's contribution to global change, and interpretations that are historically, polit…
The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene
When did the Anthropocene begin? A mid-twentieth century boundary level is stratigraphically optimal
Colonization of the Americas, 'Little Ice Age' climate, and bomb-produced carbon
A recently published analysis by Lewis and Maslin (Lewis SL and Maslin MA (2015) Defining the Anthropocene. Nature 519: 171-180) has identified two new potential horizons for the Holocene−Anthropocene boundary: 1610 (associated with European colonization of the Americas), or 1964 (the peak of the excess radiocarbon signal arising from atom bomb tests). We discuss both of these novel suggestions, and consider that there is insufficient stratigraph…
Pre-Colombian Mercury Pollution Associated with the Smelting of Argentiferous Ores in the Bolivian Andes
Late-Holocene atmospheric lead deposition in the Peruvian and Bolivian Andes
The analysis of lead (Pb) in lake-sediment cores is a useful method to reconstruct local histories of Pb pollution. Here, we use Pb concentration profiles from lake sediments to reconstruct local trajectories of pre-Colonial smelting from three metallurgical centres in the South American Andes: the Morococha mining district, Peru; the Bolivian Altiplano around Lake Titicaca; and the silver-mining centre of Potosí, Bolivia. The earliest evidence f…
Heightened sensitivity of a poorly buffered high arctic lake to late-Holocene climatic change
A diatom-based paleolimnological investigation was conducted on late Holocene sediments from a poorly buffered lake, informally named “Rock Basin Lake”, on Ellesmere Island, Arctic Canada. The fossil diatom record is unlike any other obtained thus far from high arctic regions, exhibiting dynamic assemblage shifts over the entire ∼3300 yr sedimentary record. Multiple proxies (i.e., diatoms, pH reconstructions, biogenic silica, C / N ratios, total …
A multi-proxy lacustrine record of Holocene climate change on northeastern Baffin Island, Arctic Canada
Reconstructions of past environmental changes are critical for understanding the natural variability of Earth's climate system and for providing a context for present and future global change. Radiocarbon-dated lake sediments from Lake CF3, northeastern Baffin Island, Arctic Canada, are used to reconstruct past environmental conditions over the last 11,200 years. Numerous proxies, including chironomid-inferred July air temperatures, diatom-inferr…
Spatial and temporal variability of Holocene temperature in the North Atlantic region
The early Holocene climate of the North Atlantic region was influenced by two boundary conditions that were fundamentally different from the present: the presence of the decaying Laurentide Ice Sheet (LIS) and higher than present summer solar insolation. In order to assess spatial and temporal patterns of Holocene climate evolution across this region, we collated quantitative paleotemperature records at sub-millennial resolution and synthesized t…
Yr Pollen Record of Vegetation change in the High Altitude Tropical Andes at Laguna Verde Alta, Venezuela
Pollen analysis of sediments from a high-altitude (4215 m), Neotropical (9°N) Andean lake was conducted in order to reconstruct local and regional vegetation dynamics since deglaciation. Although deglaciation commenced ∼15,500 cal yr B.P., the area around the Laguna Verde Alta (LVA) remained a periglacial desert, practically unvegetated, until about 11,000 cal yr B.P. At this time, a lycopod assemblage bearing no modern analog colonized the super…
Diatom community responses to late-Holocene climatic variability, Baffin Island, Canada
Holocene Environmental Variability in Southern Greenland Inferred from Lake Sediments
Sediments from Qipisarqo Lake provide a continuous Holocene paleoenvironmental record from southern Greenland. Following deglaciation and glacio-isostatic emergence of the basin from the sea ∼9100 cal yr B.P., proxies of lake paleoproductivity, including biogenic silica and organic matter, increased markedly until 6000 cal yr B.P. and thereafter remained stable over the ensuing warm three millennia. Subsequent decreases in these proxies, most dra…
The Last Interglacial to Glacial Transition, Togiak Bay, Southwestern Alaska
An 18-m-high coastal bluff at Togiak Bay (northwestern Bristol Bay, southwestern Alaska) exposes marine, lacustrine, fluvial, glacial, volcanic, and organic deposits that record the ∼50,000-year-long transition from the peak of the last interglaciation to the early Wisconsin glaciation. The base of the section is dominated by stratified sand and silt extending up to 4.3 m above sea level; marine diatoms are present, and pollen assemblages are cha…
Canadian Landform Examples ‐ 32
When did the Anthropocene begin? A mid-twentieth century boundary level is stratigraphically optimal
The Working Group on the Anthropocene
Re-conceptualizing the Anthropocene
Since it was first proposed in 2000, the concept of the Anthropocene has evolved in breadth and diversely. The concept encapsulates the new and unprecedented planetary-scale changes resulting from societal transformations and has brought to the fore the social drivers of global change. The concept has revealed tensions between generalized interpretations of humanity's contribution to global change, and interpretations that are historically, polit…
The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene
Scale and diversity of the physical technosphere
We assess the scale and extent of the physical technosphere, defined here as the summed material output of the contemporary human enterprise. It includes active urban, agricultural and marine components, used to sustain energy and material flow for current human life, and a growing residue layer, currently only in small part recycled back into the active component. Preliminary estimates suggest a technosphere mass of approximately 30 trillion ton…
Colonization of the Americas, 'Little Ice Age' climate, and bomb-produced carbon
A recently published analysis by Lewis and Maslin (Lewis SL and Maslin MA (2015) Defining the Anthropocene. Nature 519: 171-180) has identified two new potential horizons for the Holocene−Anthropocene boundary: 1610 (associated with European colonization of the Americas), or 1964 (the peak of the excess radiocarbon signal arising from atom bomb tests). We discuss both of these novel suggestions, and consider that there is insufficient stratigraph…
Late-Holocene atmospheric lead deposition in the Peruvian and Bolivian Andes
The analysis of lead (Pb) in lake-sediment cores is a useful method to reconstruct local histories of Pb pollution. Here, we use Pb concentration profiles from lake sediments to reconstruct local trajectories of pre-Colonial smelting from three metallurgical centres in the South American Andes: the Morococha mining district, Peru; the Bolivian Altiplano around Lake Titicaca; and the silver-mining centre of Potosí, Bolivia. The earliest evidence f…
Pre-Colombian Mercury Pollution Associated with the Smelting of Argentiferous Ores in the Bolivian Andes
Canadian Landform Examples ‐ 32
Canadian Landform Examples ‐ 32
The Last Interglacial to Glacial Transition, Togiak Bay, Southwestern Alaska
An 18-m-high coastal bluff at Togiak Bay (northwestern Bristol Bay, southwestern Alaska) exposes marine, lacustrine, fluvial, glacial, volcanic, and organic deposits that record the ∼50,000-year-long transition from the peak of the last interglaciation to the early Wisconsin glaciation. The base of the section is dominated by stratified sand and silt extending up to 4.3 m above sea level; marine diatoms are present, and pollen assemblages are cha…
Holocene Environmental Variability in Southern Greenland Inferred from Lake Sediments
Sediments from Qipisarqo Lake provide a continuous Holocene paleoenvironmental record from southern Greenland. Following deglaciation and glacio-isostatic emergence of the basin from the sea ∼9100 cal yr B.P., proxies of lake paleoproductivity, including biogenic silica and organic matter, increased markedly until 6000 cal yr B.P. and thereafter remained stable over the ensuing warm three millennia. Subsequent decreases in these proxies, most dra…
Diatom community responses to late-Holocene climatic variability, Baffin Island, Canada
Yr Pollen Record of Vegetation change in the High Altitude Tropical Andes at Laguna Verde Alta, Venezuela
Pollen analysis of sediments from a high-altitude (4215 m), Neotropical (9°N) Andean lake was conducted in order to reconstruct local and regional vegetation dynamics since deglaciation. Although deglaciation commenced ∼15,500 cal yr B.P., the area around the Laguna Verde Alta (LVA) remained a periglacial desert, practically unvegetated, until about 11,000 cal yr B.P. At this time, a lycopod assemblage bearing no modern analog colonized the super…
Heightened sensitivity of a poorly buffered high arctic lake to late-Holocene climatic change
A diatom-based paleolimnological investigation was conducted on late Holocene sediments from a poorly buffered lake, informally named “Rock Basin Lake”, on Ellesmere Island, Arctic Canada. The fossil diatom record is unlike any other obtained thus far from high arctic regions, exhibiting dynamic assemblage shifts over the entire ∼3300 yr sedimentary record. Multiple proxies (i.e., diatoms, pH reconstructions, biogenic silica, C / N ratios, total …
A multi-proxy lacustrine record of Holocene climate change on northeastern Baffin Island, Arctic Canada
Reconstructions of past environmental changes are critical for understanding the natural variability of Earth's climate system and for providing a context for present and future global change. Radiocarbon-dated lake sediments from Lake CF3, northeastern Baffin Island, Arctic Canada, are used to reconstruct past environmental conditions over the last 11,200 years. Numerous proxies, including chironomid-inferred July air temperatures, diatom-inferr…
Spatial and temporal variability of Holocene temperature in the North Atlantic region
The early Holocene climate of the North Atlantic region was influenced by two boundary conditions that were fundamentally different from the present: the presence of the decaying Laurentide Ice Sheet (LIS) and higher than present summer solar insolation. In order to assess spatial and temporal patterns of Holocene climate evolution across this region, we collated quantitative paleotemperature records at sub-millennial resolution and synthesized t…
Late-Holocene atmospheric lead deposition in the Peruvian and Bolivian Andes
The analysis of lead (Pb) in lake-sediment cores is a useful method to reconstruct local histories of Pb pollution. Here, we use Pb concentration profiles from lake sediments to reconstruct local trajectories of pre-Colonial smelting from three metallurgical centres in the South American Andes: the Morococha mining district, Peru; the Bolivian Altiplano around Lake Titicaca; and the silver-mining centre of Potosí, Bolivia. The earliest evidence f…
Pre-Colombian Mercury Pollution Associated with the Smelting of Argentiferous Ores in the Bolivian Andes
When did the Anthropocene begin? A mid-twentieth century boundary level is stratigraphically optimal
Colonization of the Americas, 'Little Ice Age' climate, and bomb-produced carbon
A recently published analysis by Lewis and Maslin (Lewis SL and Maslin MA (2015) Defining the Anthropocene. Nature 519: 171-180) has identified two new potential horizons for the Holocene−Anthropocene boundary: 1610 (associated with European colonization of the Americas), or 1964 (the peak of the excess radiocarbon signal arising from atom bomb tests). We discuss both of these novel suggestions, and consider that there is insufficient stratigraph…
The Anthropocene is functionally and stratigraphically distinct from the Holocene
Evidence of an Anthropocene epoch Humans are undoubtedly altering many geological processes on Earth—and have been for some time. But what is the stratigraphic evidence for officially distinguishing this new human-dominated time period, termed the “Anthropocene,” from the preceding Holocene epoch? Waters et al. review climatic, biological, and geochemical signatures of human activity in sediments and ice cores. Combined with deposits of new mater…
Re-conceptualizing the Anthropocene
Since it was first proposed in 2000, the concept of the Anthropocene has evolved in breadth and diversely. The concept encapsulates the new and unprecedented planetary-scale changes resulting from societal transformations and has brought to the fore the social drivers of global change. The concept has revealed tensions between generalized interpretations of humanity's contribution to global change, and interpretations that are historically, polit…
The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene
The Working Group on the Anthropocene
Scale and diversity of the physical technosphere
We assess the scale and extent of the physical technosphere, defined here as the summed material output of the contemporary human enterprise. It includes active urban, agricultural and marine components, used to sustain energy and material flow for current human life, and a growing residue layer, currently only in small part recycled back into the active component. Preliminary estimates suggest a technosphere mass of approximately 30 trillion ton…
Geology and Paleoclimatology Research (10 obras) · Geography (9 obras) · Holocene (9 obras) · Geology (8 obras) · Geology (7 obras) · Anthropocene (6 obras) · Oceanography (6 obras) · Paleontology (6 obras) · Physical geography (6 obras) · Archaeology and ancient environmental studies (5 obras)