Temperature trends during the Present and Last Interglacial periods - a multi-model-data comparison
Temperature trends during the Present and Last Interglacial periods - a multi-model-data comparison
复制标题
DOI：
10.1016/j.quascirev.2014.06.031
复制
发表时间：
2014-09-01
影响因子：
4
通讯作者：
Varma, V.
中科院分区：
文献类型：
--
作者：
Bakker, P.;Masson-Delmotte, V.;Varma, V.
尽管主要由与地球天文参数的众所周知的变化相关的日照变化所驱动，但间冰期期间气候系统的响应包括涉及大气、海洋、海冰、植被和陆地冰的多种反馈。全面的多模式 - 数据比较对于评估气候模式解析间冰期温度趋势的能力以及帮助理解所记录的气候信号和潜在的气候动力学至关重要。我们首次对当前间冰期（PIG；8 - 1.2千年）和末次间冰期（LIG；123 - 116.2千年）两个时段的千年尺度瞬态温度变化进行了多模式 - 数据比较。我们纳入了由9种不同气候模式模拟的温度趋势、来自全球117个分布地点（其中约45%位于LIG内）基于烯酮的温度重建数据以及来自格陵兰岛和南极洲的12个基于冰芯的温度趋势（其中50%位于LIG内）。这些特定间冰期时段的定义使得能够对这两个时段进行一致的相互比较，因为两者的特征都是大气温室气体浓度变化较小，更重要的是日照趋势显示出明显的相似性。我们的分析表明，一般而言，重建的PIG和LIG北半球中高纬度降温与多模式最暖月平均温度趋势吻合良好，并且这些降温趋势反映了对间冰期时段最暖月日照减少的线性响应。最显著的例外是从格陵兰岛冰芯重建的强烈的LIG降温趋势，没有任何一个模式模拟出这一趋势。在南半球中高纬度的大部分地区，PIG和LIG都发现了显著的模式 - 数据不匹配，数据显示的负温度趋势与模拟中的接近零的趋势不一致。在该地区，气候模式中当地夏季日照的正趋势被南大洋夏季海冰覆盖的增加和/或南大洋上升流的增强所抵消。如果从重建中得出的总体情况是现实的，那么南半球中高纬度的模式 - 数据不匹配意味着没有一个模式能够解析这些反馈的正确平衡，或者，间冰期南半球温度趋势是由未包含在瞬态模拟中的机制所驱动，例如南极冰盖的变化或融水引起的翻转环流的变化。（C）2014爱思唯尔有限公司。保留所有权利。
Though primarily driven by insolation changes associated with well-known variations in Earth's astronomical parameters, the response of the climate system during interglacials includes a diversity of feedbacks involving the atmosphere, ocean, sea ice, vegetation and land ice. A thorough multi-model-data comparison is essential to assess the ability of climate models to resolve interglacial temperature trends and to help in understanding the recorded climatic signal and the underlying climate dynamics. We present the first multi-model-data comparison of transient millennial-scale temperature changes through two intervals of the Present Interglacial (PIG; 8-1.2 ka) and the Last Interglacial (LIG; 123-116.2 ka) periods. We include temperature trends simulated by 9 different climate models, alkenone-based temperature reconstructions from 117 globally distributed locations (about 45% of them within the LIG) and 12 ice-core-based temperature trends from Greenland and Antarctica (50% of them within the LIG). The definitions of these specific interglacial intervals enable a consistent inter-comparison of the two intervals because both are characterised by minor changes in atmospheric greenhouse gas concentrations and more importantly by insolation trends that show clear similarities.Our analysis shows that in general the reconstructed PIG and LIG Northern Hemisphere mid-to-high latitude cooling compares well with multi-model, mean-temperature trends for the warmest months and that these cooling trends reflect a linear response to the warmest-month insolation decrease over the interglacial intervals. The most notable exception is the strong LIG cooling trend reconstructed from Greenland ice cores that is not simulated by any of the models. A striking model-data mismatch is found for both the PIG and the LIG over large parts of the mid-to-high latitudes of the Southern Hemisphere where the data depicts negative temperature trends that are not in agreement with near zero trends in the simulations. In this area, the positive local summer insolation trend is counteracted in climate models by an enhancement of the Southern Ocean summer sea-ice cover and/or an increase in Southern Ocean upwelling. If the general picture emerging from reconstructions is realistic, then the model-data mismatch in mid and high Southern Hemisphere latitudes implies that none of the models is able to resolve the correct balance of these feedbacks, or, alternatively, that interglacial Southern Hemisphere temperature trends are driven by mechanisms which are not included in the transient simulations, such as changes in the Antarctic ice sheet or meltwater-induced changes in the overturning circulation. (C) 2014 Elsevier Ltd. All rights reserved.