  We have computed 3-D displacements induced by atmospheric pressure loading
from 6-hourly surface pressure field from NCEP (National Center for
Environmental Predictions) Reanalysis data for all Very Long Baseline
Interferometry) and SLR (Satellite Laser Ranging) stations. We have
quantitatively estimated the error budget our time series of pressure loading
and found that the errors are below 15%. We validated our loading series by
comparing them with a dataset of 3.5 million VLBI observations for the period
of 1980--2003. We have shown that the amount of power which is present in the
loading time series, but does not present in the VLBI data is, on average, only
5%. We have also succeeded, for the first time, to detect horizontal
displacements caused by atmospheric loading. The correction of atmospheric
loading in VLBI data allows a significant reduction of baseline repeatability,
except for the annual component.
