Forecast Origin Dates

The J-SCOPE forecast system for Washington and Oregon coastal waters presents preliminary results for the 2017 upwelling season. Much like the rest of the U.S., spring in the PNW is forecast to begin earlier than climatological, or normal, conditions. In general, sea-surface temperature (SST) are forecasted to be slightly warmer than near climatological - but not as extreme as the past few years. Oxygen is forecasted to be higher than the climatology, which is consistent with warmer temperatures and reduced upwelling winds. Chlorophyll is forecasted to be lower, and bottom aragonite saturation state (Ω) is forecasted to become undersaturated (<1) in late summer, with less corrosive conditions found on the majority of the shelf through July.

The system predicts the timing of the spring transition from downwelling to upwelling conditions, the cumulative upwelling index, sea-surface temperature (SST), primary production, chlorophyll stock, dissolved oxygen, and sardine habitat. The forecast for 2017 is composed of three model runs that make up an ensemble. Each model run is initialized at a different time (January 5, January 15, January 25), and has complementary forcing files from the large scale model CFS. The details of the wind forcing for each model run can be found on the California Current Indicators tab. For each of the standard predicted quantities listed above, we report the ensemble average anomaly as well as the relative uncertainty within the ensemble, which is defined as the standard deviation of the ensemble divided by the mean of the ensemble and is reported as a percentage of the mean. All of these fields are reported as monthly averaged anomalies from our new climatology. An anomaly is an indication of how different conditions are to what they have been in the past; in our case, relative to the conditions between 2009 and 2014. For more information about anomalies, please see the NANOOS Climatology App. These predicted quantities are key indicators for the California Current IEA report.

The movie above shows the J-SCOPE forecast for 2017, from ensemble model run #2 initialized on January 15. More information about the three panels on the left can be found by navigating the Chlorophyll, SST, and Oxygen tabs on the left. The panel on the far right depicts the evolution of bottom water pH over the forecast period. The pH field is calculated using an empirical relationship established by Alin et al., in prep. This work is part of a collaboration between Samantha Siedlecki, J-SCOPE, and the Ocean Acidification group at NOAA PMEL. The 8-day upwelling index is calculated using the method described in Austin and Barth (2002) and can also be found under the California Current Indicators tab on the left.