Explorers' logs from the 19th century provide a source for verifying proxy records

The failure of 19th century expeditions to find and transit the Northwest Passage in the Canadian Arctic is often attributed to extraordinary cold climatic conditions associated with the 'Little Ice Age' evident in proxy records. However, an examination of a combination of historical temperature measurements and physical observations from explorers' logs reveals that observations of climate indicators, such as the distribution and thickness of annual sea ice, monthly surface air temperature and the onset of melt and freeze, were within the present range of variability for this region.