Global Temperature Responses to Large Tropical Volcanic Eruptions in Paleo Data Assimilation Products and Climate Model Simulations Over the Last Millennium
Global Temperature Responses to Large Tropical Volcanic Eruptions in Paleo Data Assimilation Products and Climate Model Simulations Over the Last Millennium
复制标题
DOI：
10.1029/2020pa004128
复制
发表时间：
2021-03
影响因子：
3.5
通讯作者：
E. Tejedor;N. Steiger;J. Smerdon;R. Serrano‐Notivoli;M. Vuille
中科院分区：
文献类型：
--
作者：
E. Tejedor;N. Steiger;J. Smerdon;R. Serrano‐Notivoli;M. Vuille
大规模火山喷发是在数年到数十年时间尺度上对全球和区域大气温度的主要扰动之一。然而，由火山喷发导致的地表温度冷却的估计幅度和持续时间方面仍然存在差异，这通过古气候代用指标和气候模型得以体现。我们利用两种最先进的数据同化产品——古水动力数据同化产品（PHYDA）和过去千年再分析（LMR），以及美国国家大气研究中心地球系统模式过去千年集合（NCAR CESM - LME）的模拟，在过去千年大规模热带火山喷发的背景下研究这些差异。我们发现，一旦去除短时间内连续发生的火山喷发的影响，PHYDA和LMR估计的全球和半球平均冷却在幅度和持续时间上是相似的。这些估计值也与仅基于或部分基于树木年轮密度的北半球重建结果吻合良好，树木年轮密度已被提议作为火山活动导致地表冷却的最准确的代用指标估计。所有基于代用指标的估计也与CESM - LME模拟的平均冷却幅度非常吻合。然而，PHYDA、LMR和CESM - LME中温度响应的空间模式仍然存在差异。与CESM - LME相比，PHYDA和LMR中冷却异常的持续时间也会延长数年。我们的研究结果表明，在解决基于代用指标和基于模型的火山活动温度响应估计之间的差异方面取得了进展，但也表明必须进一步协调这些估计，以便更好地描述未来火山喷发的风险。
Large volcanic eruptions are one of the dominant perturbations to global and regional atmospheric temperatures on timescales of years to decades. Discrepancies remain, however, in the estimated magnitude and persistence of the surface temperature cooling caused by volcanic eruptions, as characterized by paleoclimatic proxies and climate models. We investigate these discrepancies in the context of large tropical eruptions over the Last Millennium using two state‐of‐the‐art data assimilation products, the Paleo Hydrodynamics Data Assimilation product (PHYDA) and the Last Millennium Reanalysis (LMR), and simulations from the National Center for Atmospheric Research Community Earth System Model‐Last Millennium Ensemble (NCAR CESM‐LME). We find that PHYDA and LMR estimate mean global and hemispheric cooling that is similar in magnitude and persistence once effects from eruptions occurring in short succession are removed. The estimates also compare well to Northern‐Hemisphere reconstructions based solely or partially on tree‐ring density, which have been proposed as the most accurate proxy estimates of surface cooling due to volcanism. All proxy‐based estimates also agree well with the magnitude of the mean cooling simulated by the CESM‐LME. Differences remain, however, in the spatial patterns of the temperature responses in the PHYDA, LMR, and the CESM‐LME. The duration of cooling anomalies also persists for several years longer in the PHYDA and LMR relative to the CESM‐LME. Our results demonstrate progress in resolving discrepancies between proxy‐ and model‐based estimates of temperature responses to volcanism, but also indicate these estimates must be further reconciled to better characterize the risks of future volcanic eruptions.