Scientists at the University of Queensland, with colleagues in British universities, said sea levels in Tasmania remained relatively stable for much of the past 6,000 years but around 1880 they started rising drastically, increasing almost 8 inches in the last century.
Between 1900 and 1950, relative sea levels rose at an average rate of 0.16 inches per year, Queensland researcher Patrick Moss said in a university release.
The highest rates of sea level rise occurred in the 1910s with a second peak in the 1990s, he reported.
"The rise in 1910 probably reflects the end of the little ice age, when temperatures were about 1 to 2 degrees cooler in the Northern Hemisphere than today," Moss said.
"The 1990s peak is most likely indicative of human-induced climate change."
Sediment cores from Tasmania's salt marshes were studied to reconstruct a record of past sea levels, the researchers said.
"The surface of the marshes builds up over time in response to tidal inundation, providing an accurate record for sea level change," Moss said.
Past sea levels have significant implications for understanding sea level rise under a changing climate, he said.
"Any drastic changes from the norm, which persist for several decades and over a wide area, represent important climate signals," Moss said.