The Sea-Level Changes in Hong Kong From Tide-Gauge Records and Remote Sensing Observations Over the Last Seven Decades

The Sea-Level Changes in Hong Kong From Tide-Gauge Records and Remote Sensing Observations Over the Last Seven Decades

Blog Article

The importance of studying the sea-level change (SLC) in Hong Kong (HK) is emphasized by factors related to high population density, intensive urban, and industrial development, particularly along the coast that involves a considerable landreclamation.To address this issue, we investigate the spatiotemporal characteristics of SLC in the HK territories by analyzing tide-gauge (TG) records collected from 1954 to 2019 and satellite-altimetry (SA) data from 1993 to 2019.The application of the ocean-tide and inverted barometer corrections to TG data substantially decreased uncertaintie by achieving a submillimeter accuracy.

The SLC rates detected at six TG stations vary significantly even within this relatively small Horse Stretch Rugs coastline.According to our estimates, the annual rates vary between 0.32 ± 0.

51 and 4.19 ± 0.46 mm/yr from 1997 to 2019.

These large differences are related to different patterns of ocean currents and the freshwater discharge in the Pearl River Estuary.The empirical orthogonal function Plein air - Homme - Chaussures - Bottes analysis confirms the expected increasing rising in SLC with two anomalous periods during 2002–2003 and 2015–2016 that are likely attributed to the El Niño-Southern Oscillation (ENSO).SLCs are positively correlated with the ENSO index and ENSO precedes several months (normally 5 months) the interannual SLC.

The analysis of the GPS trends reveals a prevailing subsidence in the HK territories, which aggravates the relative SLC estimates.Between 1997 and 2019, the absolute sea level raised at the annual rate of 3.17 ± 1.

56 mm/yr (when using the GPS+TG) and 2.88 ± 0.59 mm/yr (when using SA observations).