Author:

Jürgen Kusche - (Institut für Geodäsie und Geoinformation, IGG, Bonn University)

Co-Investigator(s):

Roelof Rietbroek (University of Bonn)
Luciana Fenoglio (University of Bonn)
Bernd Uebbing (University of Bonn)
Matthias Becker (Technical University Darmstadt)

Abstract:

Towards consistent regional sea level budgets
Regional sea level trend contributions in mm/yr from a GRACE-Altimetry inversion (from Rietbroek et al. 2016).

The proposed research addresses the use of radar altimetry data from the missions Jason-2 and 3, Envisat, SARAL/AltiKa, CryoSat-2, and Sentinel-3 for establishing regional sea level budgets, while respecting global mean sea level budgets. The project will improve both Conventional Altimeter (CA) and Delay Doppler Altimeter (DDA) data especially in the coastal zone of selected regions and combine these data with space gravimetry data from the GRACE and from the future GRACE-FO mission. It will also contribute to the preparation to future missions such as Sentinel-6/Jason-CS. The project will address specific research topics (1), (3), (5) and (8) as outlined in the Research Announcement. Target regions are (a) the global ocean and (b) selected coastal regions such as the high latitude regions in the north-east of Greenland, the North Sea and the Bay of Bengal. Addressing the global ocean in combination with the proposed regional refinements is necessary in order to guarantee the closure of the global sea level budget while allowing a consistent transition into the regions of interest.

North Sea area
The North Sea area is marked by green stripes, while different regions physically important for the sea level in the North Sea are specifically marked in green. Furthermore.

Sea level trends
Sea level trends as determined from satellite altimetry over the period 1993-2012 (left color-coded scale). Altimeter ground-tracks are from Jason-2 (blue) and Envisat (black) satellites. Also shown are tide gauge locations from the PSMSL (inverse triangle) data base with more than 70% of monthly data in 1993-2014 (green). Vertical land motion rates from GPS at the BfG tide gauge stations (circles) and from altimetry and tide gauge sea level at some PSMSL stations (square) is color-coded (right color-coded scale).