Version number: 2.0. Most recent data included: 2 July 2017. Created on: 7 December 2017. Documentation: Lumpkin (2016) .

On this page, you'll find looper trajectory segments identified from Global Drifter Program data, using the methodology documented in Lumpkin (2016) J. Geophys. Res.

The data is available as a Matlab file loopers.mat which contains the following variables:

**T_L: integral time scale from velocity correlation function (days).**

**drogue: drogue presence (1=drogued, 0=undrogued, .5=uncertain).**

**id: unique identification number.**

**lat: latitude (degrees; negative = south).**

**lon: longitude (degrees; negative = west).**

**omega: spin omega (s^-1)**

**period: period of rotation (days; =2 pi / omega).**

**perFit: period from velocity correlation function (days).**

**persist: persistence of looping (days).**

**radius: orbital radius (m).**

**t: time (days since 1/1/1979).**

**u: zonal velocity (m/s).**

**v: meridional velocity (m/s).**There is also a Matlab file nonloopers.mat which contains the data of non-looping drifters, for those variables which are defined for nonloopers.

If you wish to obtain these data in a different format, contact Rick Lumpkin .