On the Recent Ambiguity of the North Atlantic Subpolar Gyre Index

The gyre index constructed here from satellite altimetry is related to core aspects of the North Atlantic subpolar gyre, meridional overturning circulation, hydrographic properties in the Atlantic inflows toward the Arctic, and in marine ecosystems in the northeast Atlantic Ocean. The data series spans the period January 1993 to September 2018. Data description: Monthly gyre index from January 1993 until September 2018. The data is provided in one comma separated value (csv) file with the following entries on each row: year, month, index value. The index is normalized, i.e. it has a zero mean and unit standard deviation. Positive (negative) gyre index reflects stronger (weaker) than average surface circulation of the North Atlantic subpolar gyre.