Abstract Details
Session title: JG06 - Posters - Monitoring Sea Level Changes by Satellite and In-Situ Measurements (IAG, IAPSO)
Session type: Poster Session Symposium: JG06
Presentation number: JG06 p-104
Evaluation of the Closure of Global Mean Sea Level Rise Budget over January 2005 to August 2016
Abstract title:
, M. Bagherbandi , L. E. Sjöberg .
University of Gavle, Department of Computer and Geospatial Sciences, Gavle, Sweden.
Royal Institute of Technology KTH, Division of Geodesy and Satellite Positioning, Stockholm, Sweden.
H. Amin1 1 2
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Sea level changes over time because of water mass exchange among the oceans and continents, ice sheets, and atmosphere. It fluctuates also due to variations of seawater salinity and temperature as the steric contributor. GRACE-based Stokes coefficients provide a valuable source of information, about the water mass exchange as the main contributor to the Earth’s gravity field changes, within decadal scales. Moreover, measuring seawater temperature and salinity at different layers of ocean depth, Argo floats help to model the steric component of Global Mean Sea Level. In this study, we evaluate the Global Mean Sea Level (GMSL) budget closure using satellite altimetry, GRACE, and Argo products. Hereof, considering the most recent released GRACE monthly products (RL06), we examine an iterative remove-restore method to minimize the effect of artifact leaked large signal from ice sheets and land hydrology. In addition, the effect of errors and biases in geophysical model corrections, such as GIA, on the GMSL budget closure is estimated. Moreover, we quantify the influence of spatial and decorrelation filtering of GRACE data on the GMSL budget closure. In terms of the monthly fluctuations of sea level, our results confirm that closing the GMSL budget is highly dependent on the choice of the spatial averaging filter. In addition, comparing the trends and variations for both the global mean sea level time series and those estimated for mass and steric components, we find that spatial averaging functions play a significant role in the sea level budget closure.
