Loopers


Version number: 2.2, released 9 September 2020.


Most recent data included: 05 April 2020. Documentation: Lumpkin (2016).



On this page, you will find looper trajectory segments identified from Global Drifter Program data.



Regional Cyclonic (blue) and Anticyclonic (red) Loopers

[Fig. 4] Lumpkin (2016).


Longest Looper

The longest looper on record (ID 63994870), which looped for over 308 days!


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 that 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.