Deglacial Hydroclimate of Midcontinental North America
Deglacial Hydroclimate of Midcontinental North America
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北美洲中部大陆冰消期水文气候
DOI：
10.1016/j.yqres.2015.01.001
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发表时间：
2015
影响因子：
2.3
通讯作者：
Shuman, Bryan
中科院分区：
文献类型：
--
作者：
Voelker, Steven L.;Stambaugh, Michael C.;Guyette, Richard P.;Feng, Xiahong;Grimley, David A.;Leavitt, Steven W.;Panyushkina, Irina;Grimm, Eric C.;Marsicek, Jeremiah P.;Shuman, Bryan
在最后一次冰消期，北美大陆中部的气温在博林-阿勒罗德河期间急剧变暖，经历了一个与新仙女木有关的凉爽时期，然后在全新世早期恢复到接近现代的温暖温度。然而，这一时期的水文气候的古代用记录提出了不同的证据。我们重建夏季相对湿度（RH）在末次冰消期的纤维素和叶水δ 18 O和δD结合花粉为基础的温度代理解释稳定同位素的亚化石木材的机械模型。中大陆相对湿度在末次盛冰期与现代条件相似，在Bølling-Allerød期间逐渐增加，在新仙女木期达到峰值，并在全新世早期急剧下降。这个相对湿度记录表明，冰消期的夏天更凉爽，其特点是更大的平流的水分载空气质量从墨西哥湾和随后夹带在大陆中部的高压系统在劳伦特冰盖。这些模式有助于解释在许多大平原古土壤序列中形成的深色堆积层，以及在最后一次冰消期中西部常见的非相似植被类型的发展。同样，减少早全新世RH和降水对应于减少冰川高压系统在后期阶段的冰盖崩溃。
During the last deglaciation temperatures over midcontinental North America warmed dramatically through the Bølling-Allerød, underwent a cool period associated with the Younger-Dryas and then reverted to warmer, near modern temperatures during the early Holocene. However, paleo proxy records of the hydroclimate of this period have presented divergent evidence. We reconstruct summer relative humidity (RH) across the last deglacial period using a mechanistic model of cellulose and leaf water δ18O and δD combined with a pollen-based temperature proxy to interpret stable isotopes of sub-fossil wood. Midcontinental RH was similar to modern conditions during the Last Glacial Maximum, progressively increased during the Bølling-Allerød, peaked during the Younger-Dryas, and declined sharply during the early Holocene. This RH record suggests deglacial summers were cooler and characterized by greater advection of moisture-laden air-masses from the Gulf of Mexico and subsequent entrainment over the mid-continent by a high-pressure system over the Laurentide ice sheet. These patterns help explain the formation of dark-colored cumulic horizons in many Great Plains paleosol sequences and the development of no-analog vegetation types common to the Midwest during the last deglacial period. Likewise, reduced early Holocene RH and precipitation correspond with a diminished glacial high-pressure system during the latter stages of ice-sheet collapse.
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北美中部大陆新仙女木期干旱的同位素证据
影响因子：
5.8
作者：
J. A. Dorale;L. Woźniak;E. Bettis;S. J. Carpenter;R. Mandel;E. Hajic;N. H. Lopinot;Jack H. Ray
通讯作者：
Jack H. Ray
根据纽约卡尤加湖盆地泥灰岩地层推断的全新世湖水位和气候变化
影响因子：
2
作者：
H. T. Mullins
通讯作者：
H. T. Mullins
密歇根州南部更新世晚期-全新世中期稀有气体和稳定同位素气候和冰下记录
影响因子：
5.2
作者：
M. Castro;R. Warrier;C. Hall;K. C. Lohmann
通讯作者：
K. C. Lohmann
影响因子：
4
作者：
Marsicek, Jeremiah P.;Shuman, Bryan;Oswald, W. Wyatt
通讯作者：
Oswald, W. Wyatt
DOI：
10.1073/pnas.0800560105
发表时间：
2008-05-06
影响因子：
11.1
作者：
Haynes, C. Vance, Jr.
通讯作者：
Haynes, C. Vance, Jr.