On the hydrography of Puyuhuapi Channel, Chilean Patagonia

This work describes the hydrographic conditions found in Puyuhuapi Channel (northern Chilean Patagonia) during recent years on a seasonal scale. Puyuhuapi Channel was once a glacial valley, but the retreating ice allowed the inflow of marine waters. Five surveys were conducted between 2008 and 2012; historical data from 1995 to 2007 were included. A meteorological/oceanographic buoy was also installed in the northern section of Puyuhuapi Channel and was operational beginning on April 12th, 2011. Puyuhuapi Channel's surface characteristics highlight a fresher northern part and a more haline southern part except during winter when the pattern can reverse due to the intrusion of oceanic water via Jacaf Channel. The channel exhibits a highly variable meridional and seasonal vertical stratification, especially in its northern part where during spring and summer the water column is highly stratified but partially mixed during winter. Puyuhuapi Channel is the only fjord/channel with severe hypoxic conditions in all of Chilean Patagonia.