Southern Hood Canal Dissolved Oxygen Concentrations at Historically Low Values during Winter 2003-2004 Dec 2003 data are 25% lower than the mean of past Dec’s. Jan 2004 data are lowest ever in Lynch Cove, among lowest at Great Bend. drought year El Nino year These two plots show the average oxygen for the area covered by stations P11-P15 These two plots show the minimum oxygen at two Ecology monitoring station sites in South Hood Canal Compiled by Jan Newton (Ecology/UW), Mark Warner (UW) and Renee Rose (HCSEG) using Ecology, PSAMP, PRISM, and HCDOP Citizen Monitoring data. UW O2 HCDOP

Southern Hood Canal Dissolved Oxygen Inventory at Historically Low Values during 2003-2004 Mar. 2004 data are 25-50% lower than the other Mar. data. Oxygen inventory was calculated as the total amount of oxygen below 20 m to the sea bed, in the area spanning south of Dabob Bay to the Great Bend (P11-P15). 10 x 105 mol/m is equivalent to an average concentration of 5.9 mg/l. Note also that June 2003, Dec 2003, and Mar 2004 inventories have not changed, which is not typical. Compiled by Mark Warner (UW), using PRISM, S. Kassakian (Mar. 04), and Collias et al., 1974 data. UW O2 HCDOP