David R. Greenwood
Brandon University
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Publications 116
#1Kristen M. Schlanser (UC: University of Cincinnati)
#2Aaron F. Diefendorf (UC: University of Cincinnati)H-Index: 16
Last. Daniel J. Peppe (Baylor University)H-Index: 17
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Abstract Leaf carbon isotope fractionation (Δleaf) is sensitive to environmental conditions and can provide insights into the state and evolution of leaf gas-exchange in response to climate and environment factors. In modern plants, water availability is the strongest environmental predictor of Δleaf across sites that experience relatively uniform and low concentrations of CO2 in the atmosphere (pCO2). Growth chamber experiments show Δleaf of modern plants can also be sensitive to changing pCO2....
Premise of research. Fossil fan palm fronds are well known from Eocene sites in the United States; however, although they are also known from the Paleogene Huntingdon Formation of British Columbia for over 100 years, these are poorly studied. There are early anecdotal reports of Eocene “Sabal” or Sabalites leaves from the Vancouver area, pollen from Vancouver and the interior of British Columbia, and a single megafossil palm described from the Princeton Chert, indicating past warm climates in th...
1 CitationsSource
#1Rolf W. Mathewes (SFU: Simon Fraser University)H-Index: 42
#2David R. Greenwood (Brandon University)H-Index: 29
Last. Renee Love (UIdaho: University of Idaho)
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Paleogene sediments of the Huntingdon Formation, a correlative to the Chuckanut Formation of neighboring Washington State, USA, are exposed in the greater Vancouver area, British Columbia, Canada. ...
#1Debra A. Willard (USGS: United States Geological Survey)H-Index: 29
#2Timme H. Donders (UU: Utrecht University)H-Index: 16
Last. Appy Sluijs (UU: Utrecht University)H-Index: 46
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Early Eocene global climate was warmer than much of the Cenozoic and was punctuated by a series of transient warming events or ‘hyperthermals’ associated with carbon isotope excursions when temperature increased by 4–8 °C. The Paleocene-Eocene Thermal Maximum (PETM, ~55 Ma) and Eocene Thermal Maximum 2 (ETM2, 53.5 Ma) hyperthermals were of short duration (<200 kyr) and dramatically restructured terrestrial vegetation and mammalian faunas at mid-latitudes. Data on the character and magnitude of c...
2 CitationsSource
#3David R. GreenwoodH-Index: 29
Last. Ellen D. CurranoH-Index: 13
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Last. James F. BasingerH-Index: 22
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#3Aaron F. DiefendorfH-Index: 16
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#1Markus SudermannH-Index: 1
Last. Lutz ReinhardtH-Index: 11
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#1Tammo Reichgelt (LDEO: Lamont–Doherty Earth Observatory)H-Index: 8
#2Christopher K. West (U of S: University of Saskatchewan)H-Index: 3
Last. David R. Greenwood (Brandon University)H-Index: 29
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Fossil palms provide qualitative evidence of (sub-) tropical conditions and frost-free winters in the geological past, including modern cold climate regions (e.g., boreal, or polar climates). The freeze intolerance of palms varies across different organs and life stages, with seedlings in particular less tolerant of sub-zero temperatures than adult plants, limiting successful establishment of populations while permitting adult palms to survive in cultivation outside their natural ranges. Quantit...
7 CitationsSource