Modeling regional sea level rise using local tide gauge data

Currently regional mean sea level trends and variations are inferred from the analysis of several individual local tide gauge data that span only a long period of time at a given region. In this study, we propose using amodel to merge various tide gauge data, regardless of their time span, in a single solution, to estimate parameters representative of regional mean sea level trends. The proposedmodel can account for the geographical correlations among the local tide gauge stations as well as serial correlations, if needed, for individual stations’ data. Such a vigorous regional solution enables statistically optimal uncertainties for estimated andprojected trends. Theproposed formulation also uni es all the local reference levels by modeling their offsets from a prede ned station’s reference level. To test its effectiveness, the proposedmodelwas used to investigate the regionalmean sea level variations for the coastal areas of the Florida Panhandle using 26 local tide gauge stations that span approximately 830 years ofmonthly averages from the Permanent Service forMean Sea Level repository. The new estimate for the regional trend is 2.14 mm/yr with a±0.03 mm/yr standard error, which is an order of magnitude improvement over the most recent mean sea level trend estimates and projections for the Florida region obtained from simple averages of local solutions.