GPS vertical coordinate time series noise model in Malay Peninsula based on environmental loading

This study investigates the geodetic response of the Malay Peninsula to environmental mass loading using vertical GPS coordinate time series from 39 continuous stations (2008–2011). Within the adopted GNSS processing strategy, reference-frame realisation, and the three global non-tidal loading products evaluated (GFZ, EOST and IMLS), we show that non-tidal ocean loading (NTOL) – rather than hydrological or atmospheric loads – is the dominant contributor to seasonal vertical deformation, yielding RMS reductions at all stations with a network-mean improvement of ∼6.4%, and reducing the mean annual amplitude from ∼2.6 to ∼1.4 mm (∼46%). Noise analysis indicates that the stochastic noise model of the time series is best represented by white noise plus flicker noise (WN+FN) at 37 of the 39 stations. Applying NTOL corrections results in generally modest changes in vertical velocities and their uncertainties (mean absolute differences of ∼0.04 mm/a and ∼0.10 mm/a, respectively), but these effects remain non-negligible for millimetre-per-year deformation studies, supporting more robust high-precision geodetic monitoring in this tropical coastal region.