The challenges of modeling depth-integrated marine primary productivity over multiple decades: A case study at BATS and HOT
MetadataShow full item record
The performance of 36 models (22 ocean color models and 14 biogeochemical ocean circulation models (BOGCMs)) that estimate depth-integrated marine net primary productivity (NPP) was assessed by comparing their output to in situ 14C data at the Bermuda Atlantic Time series Study (BATS) and the Hawaii Ocean Time series (HOT)over nearly two decades. Specifically, skill was assessed based on the models’ ability to estimate the observed mean, variability, and trends of NPP. At both sites, more than 90%of the models underestimated mean NPP, with the average bias of the BOGCMs being nearly twice that of the ocean color models. However, the difference in overall skill between the best BOGCM and the best ocean color model at each site was not significant. Between 1989 and 2007, in situ NPP at BATS and HOT increased by an average of nearly 2% per year and was positively correlated to the North Pacific Gyre Oscillation index. The majority of ocean color models produced in situ NPP trends that were closer to the observed trends when chlorophyll-a was derived from high-performance liquid chromatography (HPLC), rather than fluorometric or SeaWiFS data. However, this was a function of time such that average trend magnitude was more accurately estimated over longer time periods. Among BOGCMs, only two individual models successfully produced an increasing NPP trend (one model at each site). We caution against the use of models to assess multiannual changes in NPP over short time periods. Ocean color model estimates of NPP trends could improve if more high quality HPLC chlorophyll-a time series were available.
Showing items related by title, author, creator and subject.
Antoine, David; Taillandier, V.; D'Ortenzio, F. (2010)The air-sea CO2 flux, the carbon export to the deep layers, and more generally the carbon budgets are presently poorly characterized in the Mediterranean Sea. A first estimation of these fluxes at the scale of the ...
Detection of linear trends in multi-sensor time series in the presence of autocorrelated noise: Application to the chlorophyll-a SeaWiFS and MERIS datasets and extrapolation to the incoming Sentinel 3-OLCI missionSaulquin, B.; Fablet, R.; Mangin, A.; Mercier, G.; Antoine, David; Fanton d'Andon, O. (2013)The detection of long-term trends in geophysical time series is a key issue in climate change studies. This detection is affected by many factors: the size of the trend to be detected, the length of the available data ...
An evaluation of ocean color model estimates of marine primary productivity in coastal and pelagic regions across the globeSaba, V.; Friedrichs, M.; Antoine, David; Armstrong, R.; Asanuma, I.; Behrenfeld, M.; Ciotti, A.; Dowell, M.; Hoepffner, N.; Hyde, K.; Ishizaka, J.; Kameda, T.; Marra, J.; Mélin, F.; Morel, A.; O’Reilly, J.; Scardi, M.; Smith, W.; Smyth, T.; Tang, S.; Uitz, J.; Waters, K.; Westberry, T. (2011)Abstract. Nearly half of the earth’s photosynthetically fixed carbon derives from the oceans. To determine global and region specific rates, we rely on models that estimate marine net primary productivity (NPP) thus it ...