Giant dust particles at Nevado Illimani: a proxy of summertime deep convection over the Bolivian Altiplano

Abstract. A deeper understanding of past atmospheric circulation variability in the Central Andes is a high-priority topic paleoclimatology mainly because necessity to validate climate models used predict future precipitation trends and develop mitigation and/or adaptation strategies for change scenarios this region. Within context, we here investigate an 18-year firn core drilled at Nevado Illimani order interpret its mineral dust record relation seasonal processes, particular deep convection. The was dated by annual layer counting based on oscillations dust, calcium, stable isotopes. Geochemical mineralogical data show that regionally sourced winter summer. During austral summer (wet season), increase relative proportion giant particles (?>20 µm) observed, association with isotope records (?D, ?18O). It seems both deposition isotopic signature are influenced convection, which also related total amount area. This hypothesis corroborated regional meteorological data. interpretation particle suggests downdrafts due convective activity promote turbulent conditions capable suspending vicinity Illimani. Giant isotopes, when considered together, can be therefore as new proxy obtaining information about past.