Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface
The mean sea surface has an important role both in the calculation of the mean dynamic topography and in the area of sea level change as a reference surface. This paper presents a new approach to estimate a continuous spatio-temporal mean sea surface from along-track altimetric sea surface height me...
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Institute of Geodesy and Geoinformation, Theoretical Geodesy Group, University of Bonn
2022
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ftunivbonn:oai:bonndoc.ulb.uni-bonn.de:20.500.11811/9592 2023-05-15T17:36:46+02:00 Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface Borlinghaus, Moritz Neyers, Christian Brockmann, Jan Martin 2022 31 application/pdf https://hdl.handle.net/20.500.11811/9592 eng eng Institute of Geodesy and Geoinformation, Theoretical Geodesy Group, University of Bonn https://hdl.handle.net/20.500.11811/9592 In Copyright openAccess Mean sea surface Finite elements Satellite altimetry Sea level variations Ocean variability C1-smoothness ddc:526.1 doc-type:workingPaper 2022 ftunivbonn https://doi.org/20.500.11811/9592 2023-02-13T19:27:25Z The mean sea surface has an important role both in the calculation of the mean dynamic topography and in the area of sea level change as a reference surface. This paper presents a new approach to estimate a continuous spatio-temporal mean sea surface from along-track altimetric sea surface height measurements. A parametric function continuously defined in the spatial as well as temporal domain is constructed from a C 1 -smooth finite element space to represent the mean sea surface. Least-squares observation equations are set up, to estimate the unknown scaling coefficients from the sea surface height measurements as collected by altimetric exact repeat missions and geodetic missions. An advantage of the proposed method is that the surface is represented by an analytic model and the unknown parameters can be physically interpreted. Whereas the static component of the function represents the mean sea surface, the temporal component is used to absorb the ocean variability. Within a proof-of-concept study 10 years of satellite altimetry from CryoSat–2 and Jason 1–3 over the period 2010 to 2019 are used and analyzed in two study regions with different spatial resolutions. Besides the static mean sea surface, the temporal component which is estimated covers a linear trend and the annual period. The comparison of the static component to the global CNES_CLS15 MSS shows a reasonable agreement with a root mean square error below 10 cm over the entire North Atlantic. But still, systematic differences occur especially in regions with a high temporal variability. Comparisons of the temporal component with gridded sea level anomaly products show a good agreement in areas of low ocean variability, but highlights that in regions of large ocean variability the temporal basis function chosen in this initial study must be further investigated. In general, it is demonstrated that the proposed approach can be an alternative to the well established mean sea surface estimation procedures. Report North Atlantic bonndoc - The Repository of the University of Bonn |
institution |
Open Polar |
collection |
bonndoc - The Repository of the University of Bonn |
op_collection_id |
ftunivbonn |
language |
English |
topic |
Mean sea surface Finite elements Satellite altimetry Sea level variations Ocean variability C1-smoothness ddc:526.1 |
spellingShingle |
Mean sea surface Finite elements Satellite altimetry Sea level variations Ocean variability C1-smoothness ddc:526.1 Borlinghaus, Moritz Neyers, Christian Brockmann, Jan Martin Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
topic_facet |
Mean sea surface Finite elements Satellite altimetry Sea level variations Ocean variability C1-smoothness ddc:526.1 |
description |
The mean sea surface has an important role both in the calculation of the mean dynamic topography and in the area of sea level change as a reference surface. This paper presents a new approach to estimate a continuous spatio-temporal mean sea surface from along-track altimetric sea surface height measurements. A parametric function continuously defined in the spatial as well as temporal domain is constructed from a C 1 -smooth finite element space to represent the mean sea surface. Least-squares observation equations are set up, to estimate the unknown scaling coefficients from the sea surface height measurements as collected by altimetric exact repeat missions and geodetic missions. An advantage of the proposed method is that the surface is represented by an analytic model and the unknown parameters can be physically interpreted. Whereas the static component of the function represents the mean sea surface, the temporal component is used to absorb the ocean variability. Within a proof-of-concept study 10 years of satellite altimetry from CryoSat–2 and Jason 1–3 over the period 2010 to 2019 are used and analyzed in two study regions with different spatial resolutions. Besides the static mean sea surface, the temporal component which is estimated covers a linear trend and the annual period. The comparison of the static component to the global CNES_CLS15 MSS shows a reasonable agreement with a root mean square error below 10 cm over the entire North Atlantic. But still, systematic differences occur especially in regions with a high temporal variability. Comparisons of the temporal component with gridded sea level anomaly products show a good agreement in areas of low ocean variability, but highlights that in regions of large ocean variability the temporal basis function chosen in this initial study must be further investigated. In general, it is demonstrated that the proposed approach can be an alternative to the well established mean sea surface estimation procedures. |
format |
Report |
author |
Borlinghaus, Moritz Neyers, Christian Brockmann, Jan Martin |
author_facet |
Borlinghaus, Moritz Neyers, Christian Brockmann, Jan Martin |
author_sort |
Borlinghaus, Moritz |
title |
Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
title_short |
Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
title_full |
Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
title_fullStr |
Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
title_full_unstemmed |
Towards the Development of a Continuous Spatio-Temporal Finite Element Based Representation of the Mean Sea Surface |
title_sort |
towards the development of a continuous spatio-temporal finite element based representation of the mean sea surface |
publisher |
Institute of Geodesy and Geoinformation, Theoretical Geodesy Group, University of Bonn |
publishDate |
2022 |
url |
https://hdl.handle.net/20.500.11811/9592 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
https://hdl.handle.net/20.500.11811/9592 |
op_rights |
In Copyright openAccess |
op_doi |
https://doi.org/20.500.11811/9592 |
_version_ |
1766136351719161856 |