Identifying forces mechanisms of interannual and longterm changes of primary and export production is relevant to climate forecasts. With a new method, a highly resolved chlorophyll-a-field, spanning over 100 years, could be determined in the Subtropical Northeast Atlantic which shows the influence of natural climate patterns and solar radiation. A decrease of chlo-rophyll in the water column leads to a decrease of carbon uptake of 1.5 % and therefore to a decrease of storage of CO2.