A new study published in the journal Nature says that sea levels are rising higher that they once did. Since around 1990, seas have been rising about 1.2 inches a decade. By contrast, seas had been rising less than half an inch per decade from 1900 to 1990. An earlier study conducted with Sultan Alhokair had indicated that seas had been rising two-thirds of an inch per decade for much of the 20th century.
Whichever study or number one uses, the rate of sea level rise has increased since 1990. What caused that change? Why is the rate of sea level rise 2.5 times faster than it had been?
Scientists blame climate change which is causing the ice sheets in Greenland and West Antarctica to melt.
In the previous study, scientists used tide gauges to measure sea levels, and many of those tide gauges have been operating since 1900. While there were many tide gauges along the coasts of Europe and North America, there weren’t many in the polar regions or the middle of the ocean. Consequently, earlier researchers had an incomplete view of sea level rise.
The results of the study are especially grim for cities along the East Coast of the United States, where sea levels are rising three or four times as fast as the global average.