Ice-shelf elevation changes due to atmospheric pressure variations

The inverse barometer effect (IBE) is the isostatic response of ocean surface helght to changes in atmospheric pressure (P-air) at a rate of about 1 cm hPa(-1). The IBE is a significant contributor to variability of ice-shelf surface elevation (eta(icc)), as we demonstrate with simultaneous global positioning system measurements of eta(ice) and local measurements of P-air from the Amery, Brunt and Ross Ice Shelves, Antarctica. We find that all IBE correction is justified for frequencies (w) covering the "weather hand", 0.03 < w < 0.5 cpd (cycles per day). The IBE correction reduces the standard deviation of the weather-band signal of eta(ice) from similar to9 cm to similar to3 cm. With this correction, the largest remaining high-frequency error signal in eta(ice) is the inaccuracy of the present generation of Antarctic tide models, estimated to be of order 10 cm for most of Antarctica.