PISCO researchers Jack Barth and Francis Chan are reporting low dissolved oxygen (DO) concentrations off the central coast of
Researchers from the Northwest Fisheries Science Center (at HMSC in Newport, OR) report that they are already seeing fairly low oxygen values in June (1.40 ml/L at NH05 on 22 June at 56 m depth = hypoxic) yet upwelling has been very weak this spring (based on the PFEL upwelling index). Local winds have been weak as well although they were blowing pretty strong on June 24th. There has been a huge bloom the past week or two so maybe it has already begun to sink to the bottom and began to decompose. In addition, copepod biomass is twice
ODFW attempted to conduct their pre-season sampling on 5/31-6/1, but were shut out due to very poor underwater visibility on the seafloor. However, the limited video footage that was obtained at Cape Perpetua was indicative of non-hypoxic conditions (e.g., plentiful, active fish, healthy-looking epibenthic macroinvertebrates). Video review and analysis of ROV footage dating to 2000 is ongoing, with results and a report planned for later this year. An analysis of fisheries performance versus hypoxia is also planned for later this year.
The PISCO Offshore team has been working off of Strawberry Hill to service and deploy moorings. These moorings include sensors that measure dissolved oxygen, conductivity, fluorescence, and temperature. ADCPs (Acoustic Doppler Current Profilers) are also deployed and operating as expected. The initial data shows oxygen levels to be hovering between 8.5 and 10.0 ml/L, which are well above hypoxic levels (1.4 ml/L). Wat
Researchers are unsure what hypoxia conditions will look like in 2011. Field researchers will be back in the field starting at the end of April and will be looking for factors that have been important in the past: spring transition, upwelling-favorable winds, wind intensity, and deep water conditions.
AUGUST 12, 2010
The PISCO hypoxia team at Oregon State University started monitoring the coastal ocean off Oregon in early April this year. The spring transition occurred in late April or early May. Spring transition signals a change in coastal wind patterns. Each year, the coastal winds switch from the southerly winds of winter to the northerly winds of summer.