Historical records of San Rafael glacier advances (North Patagonian Icefield): another clue to 'Little Ice Age' timing in southern Chile?

Abstract

Past ice lobe behaviour at Laguna San Rafael is described in documents provided by Spanish and then Chilean explorers from the late seventeenth to the early twentieth centuries. These records begin in AD 1675, when temperate conditions, probably similar to those at present, prevailed. At that point, the glacier was confined within its valley, not penetrating the Laguna. The glacier advanced noticeably during the nineteenth century and probably reached a maximum position for the `Little Ice Age' around AD 1875. The historical sources suggest a slight retreat in AD 1904 in relation to the conditions prevailing 29 years earlier. The historical data show that the eighteenth to nineteenth century cooling period at San Rafael glacier was within the temporal window of the European `Little Ice Age'. This work provides independent, direct historical evidence for the occurrence of this event in southern Chile.