Version: 1

18-year average height-change time series for Antarctic ice shelves.

The complete description of processing steps is described by Paolo et al. (2016).

Time series were derived from 18 years (1994-2012) of continuous satellite radar-altimeter measurements of changes in ice-shelf surface height (European Space Agency (ESA) ERS-1, ERS-2 and Envisat missions). 

Time series are full-ice-shelf average height changes [m] every three months (72 time steps). The time series are referenced to their mean value. 

The time series have been corrected for ocean tides, atmospheric pressure (inverse barometer), regional sea-level trends, and surface scattering variation.

Polynomial-trend time series were estimated using lasso-regularized regression and ten-fold cross-validation (see Paolo et al., 2016).

Error bars [m] in the height time series are two standard errors,
which account for variance, number of observations, and backscatter correction.

Error bars [m] in the polynomial-trend time series are two standard errors, derived from 1000 Bootstrap samples (see Paolo et al., 2016).

Files are (ASCII comma-separated-values):

ice_shelf_dh_mean_v1_height.csv            # Ice-shelf-average height change [m]
ice_shelf_dh_mean_v1_height_err.csv        # Two standard error of height changes [m]
ice_shelf_dh_mean_v1_height_poly.csv       # Polynomial trend fit [m]
ice_shelf_dh_mean_v1_height_poly_err.csv   # Two standard error of polynomial fit [m]
ice_shelf_dh_mean_v1_example.png           # Example average time series of height change

Columns are (CSV header):

Year        # time [year]
ice-shelf   # height change of 'ice-shelf/region' [m]

Notes:

Due to the wide radar altimeter (pulse-limited) footprint (~3-5 km), there is limited coverage near the grounding lines. This can potentially underestimate changes near some of the rapidly-changing grounding lines (e.g. Pine Island); see references for detailed information.

References:

Paolo F.S, H.A. Fricker, L. Padman, Constructing improved decadal records of Antarctic ice-shelf height change from multiple satellite radar altimeters, Remote Sensing of Environment, vol.177, pp.192-205 (2016). doi:10.1016/j.rse.2016.01.026

Paolo F.S., H.A. Fricker, L. Padman, Volume loss from Antarctic ice shelves is accelerating, Science, vol.348, pp.327-331 (2015). doi:10.1126/science.aaa0940


Fernando Paolo <fspaolo@gmail.com>
Jan 26, 2017