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Common Era temperature variability has been a prominent component in Intergovernmental Panel on Climate Change reports over the last several decades and was twice featured in their Summary for Policymakers. A single reconstruction of mean Northern Hemisphere temperature variability was first highlighted in the 2001 Summary for Policymakers, despite other estimates that existed at the time. Subsequent reports assessed many large-scale temperature reconstructions, but the entirety of Common Era temperature history in the most recent Sixth Assessment Report of the Intergovernmental Panel on Climate Change was restricted to a single estimate of mean annual global temperatures. We argue that this focus on a single reconstruction is an insufficient summary of our understanding of temperature variability over the Common Era. We provide a complementary perspective by offering an alternative assessment of the state of our understanding in high-resolution paleoclimatology for the Common Era and call for future reports to present a more accurate and comprehensive assessment of our knowledge about this important period of human and climate history. 

Abstract. The mid-17th century is characterized by a clusterof explosive volcanic eruptions in the 1630s and 1640s, climatic conditionsculminating in the Maunder Minimum, and political instability andfamine in regions of western and northern Europe as well as China and Japan. This contribution investigates the sources of the eruptions of the 1630s and 1640s and their possible impact on contemporary climate using ice core, tree-ring, and historical evidence but will also look into thesocio-political context in which they occurred and the human responses theymay have triggered. Three distinct sulfur peaks are found in the Greenlandice core record in 1637, 1641–1642, and 1646. In Antarctica, only oneunambiguous sulfate spike is recorded, peaking in 1642. The resultingbipolar sulfur peak in 1641–1642 can likely be ascribed to the eruption ofMount Parker (6∘ N, Philippines) on 26 December 1640, but sulfateemitted from Komaga-take (42∘ N, Japan) volcano on 31 July 1641has potentially also contributed to the sulfate concentrations observed inGreenland at this time. The smaller peaks in 1637 and 1646 can bepotentially attributed to the eruptions of Hekla (63∘ N, Iceland)and Shiveluch (56∘ N, Russia), respectively. To date, however,none of the candidate volcanoes for the mid-17th century sulfate peakshave been confirmed with tephra preserved in ice cores. Tree-ring andwritten sources point to cold conditions in the late 1630s and early 1640sin various parts of Europe and to poor harvests. Yet the early 17thcentury was also characterized by widespread warfare across Europe – and in particular the Thirty Years' War (1618–1648) – rendering any attribution of socio-economic crisis to volcanism challenging. In China and Japan, historical sources point to extreme droughts and famines starting in 1638 (China) and 1640 (Japan), thereby preceding the eruptions of Komaga-take (31 July 1640) and Mount Parker (4 January 1641). The case of the eruptioncluster between 1637 and 1646 and the climatic and societal conditionsrecorded in its aftermath thus offer a textbook example of difficulties in(i) unambiguously distinguishing volcanically induced cooling, wetting, ordrying from natural climate variability and (ii) attributing politicalinstability, harvest failure, and famines solely to volcanic climaticimpacts. This example shows that while the impacts of past volcanism mustalways be studied within the contemporary socio-economic contexts, it isalso time to move past reductive framings and sometimes reactionaryoppositional stances in which climate (and environment more broadly) eitheris or is not deemed an important contributor to major historical events.