Observations of gravity field variations from ground and satellite data
The Earth's gravity field consists of several constituents of geophysical nature. By using geodetic observations techniques to observe gravity field variations, it is possible to monitor these geophysical processes. This thesis tries to analyse how Earth's gravity field varies on a global...
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Norwegian University of Life Sciences, Ås
2014
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ftunivmob:oai:nmbu.brage.unit.no:11250/218741 2023-05-15T13:48:23+02:00 Observations of gravity field variations from ground and satellite data Observasjoner av tyngdefeltvariasjoner fra terrestriske og satellittbaserte data Helland, Alexander 2014 application/pdf http://hdl.handle.net/11250/218741 eng eng Norwegian University of Life Sciences, Ås http://hdl.handle.net/11250/218741 118 Geomatics Physical Geodesy Absolute gravimetry GRACE VDP::Mathematics and natural science: 400::Mathematics: 410::Topology/geometry: 415 VDP::Technology: 500::Information and communication technology: 550::Geographical information systems: 555 Master thesis 2014 ftunivmob 2021-09-23T20:15:04Z The Earth's gravity field consists of several constituents of geophysical nature. By using geodetic observations techniques to observe gravity field variations, it is possible to monitor these geophysical processes. This thesis tries to analyse how Earth's gravity field varies on a global and on a local scale. In addition, attempts have been made to offer geophysical explanations to the variations observed. Observational material gathered through terrestrial gravimetry from three different locations in Norway, as well as satellite data from GRACE, has been used to study Earth's gravity field. Performing an analysis covering several years using terrestrial gravimetry data, shows how Norway is influenced by glacial isostatic adjustment (GIA). The GIA induced vertical displacement was estimated to be 8.7 mm for \AA s and 8.0 mm for Trysil. The Trysil observations also reveal severe amounts of seasonal gravity variations, ranging from $\pm$ 4 microgals to $\pm$ 8 microgals. These seasonal gravity variations are correlated with the local hydrology cycle. Using monthly GRACE solutions, this thesis shows how GIA influence Fennoscandia, northern parts of North America and Antarctica by increasing the regional mass distribution. Seasonal hydrology variations in the Amazon and southern parts of Africa can be detected by GRACE as well. Finally, this thesis shows how GRACE and terrestrial data can detect some of the same gravity field variations. However, due to some methodology differences, the different gravity field signals behave differently. M-GEOM Master Thesis Antarc* Antarctica Fennoscandia Open archive Norwegian University of Life Sciences: Brage NMBU Norway |
institution |
Open Polar |
collection |
Open archive Norwegian University of Life Sciences: Brage NMBU |
op_collection_id |
ftunivmob |
language |
English |
topic |
Geomatics Physical Geodesy Absolute gravimetry GRACE VDP::Mathematics and natural science: 400::Mathematics: 410::Topology/geometry: 415 VDP::Technology: 500::Information and communication technology: 550::Geographical information systems: 555 |
spellingShingle |
Geomatics Physical Geodesy Absolute gravimetry GRACE VDP::Mathematics and natural science: 400::Mathematics: 410::Topology/geometry: 415 VDP::Technology: 500::Information and communication technology: 550::Geographical information systems: 555 Helland, Alexander Observations of gravity field variations from ground and satellite data |
topic_facet |
Geomatics Physical Geodesy Absolute gravimetry GRACE VDP::Mathematics and natural science: 400::Mathematics: 410::Topology/geometry: 415 VDP::Technology: 500::Information and communication technology: 550::Geographical information systems: 555 |
description |
The Earth's gravity field consists of several constituents of geophysical nature. By using geodetic observations techniques to observe gravity field variations, it is possible to monitor these geophysical processes. This thesis tries to analyse how Earth's gravity field varies on a global and on a local scale. In addition, attempts have been made to offer geophysical explanations to the variations observed. Observational material gathered through terrestrial gravimetry from three different locations in Norway, as well as satellite data from GRACE, has been used to study Earth's gravity field. Performing an analysis covering several years using terrestrial gravimetry data, shows how Norway is influenced by glacial isostatic adjustment (GIA). The GIA induced vertical displacement was estimated to be 8.7 mm for \AA s and 8.0 mm for Trysil. The Trysil observations also reveal severe amounts of seasonal gravity variations, ranging from $\pm$ 4 microgals to $\pm$ 8 microgals. These seasonal gravity variations are correlated with the local hydrology cycle. Using monthly GRACE solutions, this thesis shows how GIA influence Fennoscandia, northern parts of North America and Antarctica by increasing the regional mass distribution. Seasonal hydrology variations in the Amazon and southern parts of Africa can be detected by GRACE as well. Finally, this thesis shows how GRACE and terrestrial data can detect some of the same gravity field variations. However, due to some methodology differences, the different gravity field signals behave differently. M-GEOM |
format |
Master Thesis |
author |
Helland, Alexander |
author_facet |
Helland, Alexander |
author_sort |
Helland, Alexander |
title |
Observations of gravity field variations from ground and satellite data |
title_short |
Observations of gravity field variations from ground and satellite data |
title_full |
Observations of gravity field variations from ground and satellite data |
title_fullStr |
Observations of gravity field variations from ground and satellite data |
title_full_unstemmed |
Observations of gravity field variations from ground and satellite data |
title_sort |
observations of gravity field variations from ground and satellite data |
publisher |
Norwegian University of Life Sciences, Ås |
publishDate |
2014 |
url |
http://hdl.handle.net/11250/218741 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Antarc* Antarctica Fennoscandia |
genre_facet |
Antarc* Antarctica Fennoscandia |
op_source |
118 |
op_relation |
http://hdl.handle.net/11250/218741 |
_version_ |
1766249199251226624 |