Geoscience Reference
In-Depth Information
Fig. 2
Spatial variations of surface pressure anomaly and modeled vertical displacements at 00
UTC on January 1, 2010
Complex interactions between the Earth and the atmosphere lead these global
atmospheric pressure variations to produce several geodynamic effects as e.g. sur-
face load deformations (Farrell
1972
; Rabbel and Zschau
1985
; van Dam and Wahr
1987
), changes of the gravity potential (Farrell
1972
; Boy and Chao
2009
), and vari-
ations in the Earth's rotational motion (Wahr
1983
). In the context of surface load
deformations, global variations in surface pressure can displace the Earth's surface by
more than 1 cm both vertically and horizontally on annual to sub-diurnal timescales.
Figure
2
shows spatial variations of land surface pressure and modeled vertical dis-
placements over the globe with an obvious negative correlation. A large (positive)
pressure anomaly of about 30hPa over Siberia deforms the Earth's surface by about
10mm. On the other side, a negative pressure anomaly (
≈−
20 hPa) over Europe
uplifts the region. The magnitude of atmospheric pressure loading (APL) effects for
