Upwelling Indices Time Series over the four Major Eastern Boundary Upwelling Systems from the 1981-2019 European Space Agency Sea Surface Temperature Climate Change Initiative (ESA SST CCI) Analysis Product.

Upwelling ecosystems located on the eastern side of the Atlantic and Pacific oceans are known for their high biological productivity that supports large marine populations and for their major contribution to the world marine fish catches. Ocean acidification, algal blooms and low oxygen events over these continental shelves are tightly linked to the dynamics of the upwelling process and these regional-scale dynamics are not well represented in climate models. As a part of the ESA Satellite Oceanographic Datasets for Acidification (OceanSODA) project, a new SST-based upwelling indices (UI) time series is proposed. Index calculations are based on the ESA SST CCI product providing daily global gap-free SST fields at a 0.05° horizontal grid resolution and covering the period 1st September 1981 onwards. The method used to derive the UI is based on a segmentation algorithm using Gaussian mixture models (GMM). The methodology to derive the SST-based UI and the ability of the new data set to monitor the spatial and temporal variability of the upwelling systems will be presented.