GLOBAL INFLUENCE OF THE AD1600 ERUPTION OF HUAYNAPUTINA, PERU

It has long been estabished that gas and fine ash from large equatoria l explosive eruptions can spread globally, and that the sulphuric acid that is consequently produced in the stratosphere can cause a small, but statistically significant, cooling of global temperatures(1,2). Ce ntral to revealing the ancient volcano-climate connection have been st udies linking single eruptions to features of climate-proxy records su ch as found in ice-core(3-5) and tree-ring(6-8) chronologies. Such rec ords also suggest that the known inventory of eruptions is incomplete, and that the climatic significance of unreported or poorly understood eruptions remains to be revealed, The AD1600 eruption of Huaynaputina , in southern Peru, has been speculated to be one of the largest erupt ions of the past 500 years; acidity spikes from Greenland and Antarcti ca ice(3-5), tree-ring chronologies(6-8), along with records of atmosp heric perturbations in early seventeenth-century Europe and China(9,10 ), implicate an eruption of similar or greater magnitude than that of Krakatau in 1883. Here we use tephra deposits to estimate the volume o f the AD1600 Huaynaputina eruption, revealing that it was indeed one o f the largest eruptions in historic times. The chemical characteristic s of the glass from juvenile tephra allow a firm cause-effect link to be established with glass from the Antarctic ice, and thus improve on estimates of the stratospheric loading of the eruption.