Spatial Optimal Interpolation of Aquarius Sea Surface Salinity: Algorithms and Implementation in the North Atlantic*

• DOI: 10.1175/jtech-d-13-00241.1
• Publication Date: 2014-04-09T21:26:58Z
• Authors: Oleg Melnichenko; Peter Hacker; Nikolai Maximenko; Gary Lagerloef; James Potemra
• Keywords: SSS*; Interpolation; Spurious relationship

Abstract A method is presented for mapping sea surface salinity (SSS) from Aquarius level-2 along-track data in order to improve the utility of SSS fields at short length [O(150 km)] and time [O(1 week)] scales. The based on optimal interpolation (OI) derives an estimate a grid point as weighted sum nearby satellite observations. weights are optimized minimize estimation error variance. As initial demonstration, applied North Atlantic. key element that it takes into account so-called long-wavelength errors (by analogy with altimeter applications), referred here interbeam ascending/descending biases, which appear correlate over long distances along tracks. developed technique also includes filtering prior OI use realistic correlation scales mesoscale anomalies. All these features shown result more accurate maps, free spurious structures. trial analysis produced Atlantic uniform 0.25° resolution temporal one week, encompassing period September 2011 through August 2013. brief statistical description, comparison between maps concurrent situ data, used demonstrate potential products document structure ~150-km weekly