Sea level rises: Arguing the nanometre to defocus from the missed meter

摘要

The sea level rates of rise of the worldwide surveys by the Permanent Service on Mean Sea Level (PSMSL) or the United States surveys by the National Oceanic and Atmospheric Administration (NOAA) have shown stable sea level rises, with average values over hundreds of tide gauges very small, and negligible time rates of changes of these values, but eventually negative. To defocus from the only +0.25 mm/year of about constant sea level rises at the more than 100 worldwide tide gauges of length exceeding 60 years (the minimum to clear the trend of the multi decadal oscillations), translating in only 3.75 mm sea level rise after 15 years, an incredible paper has recently argued that the sea level acceleration, rather than being small negative when computed over a significant population of tide gauges as the time rate of change of the sea level rise obtained by linear fitting of all the recorded data, could possibly be small positive changing the way sea level rate of rise and acceleration are computed. I comment as this latest work is only the latest attempt of a long series to make unclear what is otherwise very clear - there is no alarming sea level rise.