According to the study, 1993 was the turning point: until that year, sea level rose significantly slower
Over the last 25 years, sea-level rise worldwide has doubled than expected, according to an international study published in the Proceedings of the National Academy of Sciences (PNAS).
The work, which has involved the researcher of the Mediterranean Institute of Advanced Studies Marta Marcos, has contrasted estimates of sea level rise with actual measurements provided by satellites and has found that sea level rise almost doubles The expected values.
For the research, scientists have analyzed the historical data of tide gauges, the instruments used to measure coastal changes until 1992, when the first satellites were launched capable of monitoring sea levels.
After selecting the longest and highest quality records, scientists have corrected the estimates taking into account processes not directly related to the oceans, such as earth’s crust movements or changes in Earth’s shape.
The researchers have combined all these data and have corrected them with a new methodology more coherent with the marine dynamics, which has allowed redefining the available information.
“It is important to accurately determine the rate of sea level rise in the past decades to know what the processes involved and how each respond to global warming, ” explains Marta Marcos.
” The trend would have changed and polar ice sheets would have contributed more to sea level rise, according to the study. “It implies that the difference between the pre-1993 data and the precise satellites observations is greater and, therefore, we almost doubled the acceleration in the rise of sea level with respect to the values that had been adopted until now”, concludes Marcos