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作者：Brainard, Jeffrey
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作者：Clark, Peter U.; Shakun, Jeremy D.; Rosenthal, Yair; Koehler, Peter; Bartlein, Patrick J.
作者单位：Oregon State University; Ulster University; Boston College; Rutgers University System; Rutgers University New Brunswick; Rutgers University System; Rutgers University New Brunswick; Helmholtz Association; Alfred Wegener Institute, Helmholtz Centre for Polar & Marine Research; University of Oregon
摘要：Much of our understanding of Cenozoic climate is based on the record of delta 18O measured in benthic foraminifera. However, this measurement reflects a combined signal of global temperature and sea level, thus preventing a clear understanding of the interactions and feedbacks of the climate system in causing global temperature change. Our new reconstruction of temperature change over the past 4.5 million years includes two phases of long-term cooling, with the second phase of accelerated cool...
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作者：Clery, Daniel
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作者：Aimone, James B.; Agarwal, Sapan
作者单位：United States Department of Energy (DOE); Sandia National Laboratories; United States Department of Energy (DOE); Sandia National Laboratories
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作者：Dial, Roman J.; Maher, Colin T.; Hewitt, Rebecca E.; Wockenfuss, Amy M.; Wong, Russell E.; Crawford, Daniel J.; Zietlow, Madeline G.; Sullivan, Patrick F.
作者单位：Alaska Pacific University; University of Alaska System; University of Alaska Anchorage; Northern Arizona University; United States Department of Agriculture (USDA); United States Forest Service; Amherst College; University of Alaska System; University of Alaska Anchorage
摘要：Climate-induced northward advance of boreal forest is expected to lessen albedo, alter carbon stocks, and replace tundra, but where and when this advance will occur remains largely unknown. Using data from 19 sites across 22 degrees of longitude along the tree line of northern Alaska, we show a stronger temporal correlation of tree ring growth with open water uncovered by retreating Arctic sea ice than with air temperature. Spatially, our results suggest that tree growth, recruitment, and rang...
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作者：Thorp, H. Holden
摘要：University of Pennsylvania climate scientist Michael Mann was awarded more than $1 million in a lawsuit against bloggers who accused him of scientific misconduct in inflammatory terms, likening his treatment of data to what a noted child molester did to children. The verdict suggests that there are limits to which scientists working on politically sensitive topics can be falsely attacked. But the case also says something profound about the difference between matters of opinion and scientific i...
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作者：Alexander, Brandon W.; Bartfield, Noah M.; Gupta, Vaani; Mercado, Brandon Q.; Del Campo, Mark; Herzon, Seth B.
作者单位：Yale University; Yale University; Rigaku Corporation; Yale University; Yale University
摘要：Securines and securamines are cytotoxic alkaloids that contain reactive alkene and heterocyclic residues embedded in skeletons comprising four to six oxidized rings. This structural complexity imparts a rich chemistry to the isolates but has impeded synthetic access to the structures in the nearly three decades since their isolation. We present a flexible route to eight isolates that exemplify the three skeletal classes of metabolites. The route proceeds by the modular assembly of the advanced...
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作者：Falahatkar, Bahram
作者单位：University of Guilan
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作者：Weber, James; King, James A.; Abraham, Nathan Luke; Grosvenor, Daniel P.; Smith, Christopher J.; Shin, Youngsub Matthew; Lawrence, Peter; Roe, Stephanie; Beerling, David J.; Martin, Maria Val
作者单位：University of Sheffield; University of Cambridge; University of Cambridge; UK Research & Innovation (UKRI); Natural Environment Research Council (NERC); NERC National Centre for Atmospheric Science; University of Leeds; Met Office - UK; Hadley Centre; University of Leeds; International Institute for Applied Systems Analysis (IIASA); National Center Atmospheric Research (NCAR) - USA; World Wildlife Fund
摘要：Forestation is widely proposed for carbon dioxide (CO2) removal, but its impact on climate through changes to atmospheric composition and surface albedo remains relatively unexplored. We assessed these responses using two Earth system models by comparing a scenario with extensive global forest expansion in suitable regions to other plausible futures. We found that forestation increased aerosol scattering and the greenhouse gases methane and ozone following increased biogenic organic emissions....
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作者：Al-Aly, Ziyad; Topol, Eric
作者单位：Washington University (WUSTL); Scripps Research Institute
