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Full-Text Articles in Other Oceanography and Atmospheric Sciences and Meteorology

Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide Oct 2015

Aulacoseira Stevensiae Sp. Nov. (Coscinodiscophyceae, Bacillariophyta), A New Diatom From Ho Ba Bê, Bac Kan Province, Northern Viêt Nam, D. Marie Weide

Department of Earth and Atmospheric Sciences: Faculty Publications

A new species of Aulacoseira Thwaites is described from piston core samples from Ho Ba Bê in the karst region of northern Viêt Nam. Although it closely resembles Aulacoaseira subborealis (Nygaard) Denys, Muylaert & Krammer, A. stevensiae Weide sp. nov. is designated a new species based mainly on morphological differences in the spines, including invariably inclined spines that are rounded, differences in the Ringleiste, areola pattern and overall size. Aulacoseira stevensiae is present throughout a core that spans the last 500 years. It was a major component of the diatom community, but the populations have recently decreased, possibly being outcompeted …


Early Miocene Antarctic Glacial History: New Insights From Heavy Mineral Analysis From Andrill And–2a Drill Core Sediments, Francesco Iacoviello, Giovanna Giorgetti, Isabella Turbanti Memmi, Sandra Passchier Apr 2015

Early Miocene Antarctic Glacial History: New Insights From Heavy Mineral Analysis From Andrill And–2a Drill Core Sediments, Francesco Iacoviello, Giovanna Giorgetti, Isabella Turbanti Memmi, Sandra Passchier

ANDRILL Research and Publications

The present study deals with heavy mineral analysis of late Early Miocene marine sediments recovered in the McMurdo Sound region (Ross Sea, Antarctica) during the ANDRILL— SMS Project in 2007. The main objective is to investigate how heavy mineral assemblages reflect different source rocks and hence different provenance areas. These data contribute to a better understanding of East Antarctica ice dynamics in the Ross Sea sector during the Early Miocene (17.6–20.2 Ma), a time of long-term global warming and sea level rise. The AND-2A drill core recovered several stratigraphic intervals that span from Early Miocene to Pleistocene and it collected …


Multi-Scale Evaluation Of Light Use Efficiency In Modis Gross Primary Productivity For Croplands In The Midwestern United States, Qinchuan Xin, Mark Broich, Andrew E. Suyker, Le Yu, Peng Gong Jan 2015

Multi-Scale Evaluation Of Light Use Efficiency In Modis Gross Primary Productivity For Croplands In The Midwestern United States, Qinchuan Xin, Mark Broich, Andrew E. Suyker, Le Yu, Peng Gong

School of Natural Resources: Faculty Publications

Satellite remote sensing provides continuous observations of land surfaces, thereby offering opportunities for large-scale monitoring of terrestrial productivity. Production Efficiency Models (PEMs) have been widely used in satellite-based studies to simulate carbon exchanges between the atmosphere and ecosystems. However, model parameterization of the maximum light use efficiency (ε*GPP) varies considerably for croplands in agricultural studies at different scales. In this study, we evaluate cropland ε*GPP in the MODIS Gross Primary Productivity (GPP) model (MOD17) using in situ measurements and inventory datasets across the Midwestern US. The site-scale calibration using 28 site-years tower measurements derives ε*GPP values …


On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell Jan 2015

On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell

United States Geological Survey: Staff Publications

Patterns, mechanisms, projections, and consequences of tree mortality and associated broadscale forest die-off due to drought accompanied by warmer temperatures—‘‘hotter drought’’, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortalityrelevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases …