Better Use of High-Latitude Data in Assimilative Ocean Modeling

Using an Observing System Simulation Experiment framework, we demonstrate that SSH measurements at high latitudes are being under-utilized. SSH observations are used to create synthetic temperature and salinity profiles, which are then assimilated. In some cases, observations are discarded due to low thermal stratification, but it can be shown that even in these cases, especially when co-located SST observations are present, synthetic profiles can be used to properly reflect changes and adjust the product toward reality. One caveat is that changes in Arctic climatology mean that in some cases, the data may be nudging an assimilative product toward an outdated climatology; thus it is possible that a modified or updated climatology is necessary to reflect recent and ongoing Arctic warming. The overall conclusion is that there are data available that could improve our operational product, if we are careful in our use of the products and systems already available to us.