Re:What Climate Change Looks Like: Miami’s $300M Pumps
by DrScump on Friday December 11, 2015 @02:04AM
(#10715809)
"Researchers at the University of Miami have been carefully measuring sea levels at Virginia Key, just south of Miami Beach, for nearly two decades, and say that in that time the sea has risen nearly four inches."
There has been no land subsidence at all, apparently.
Re:What Climate Change Looks Like: Miami’s $300M Pumps
by dalke on Friday December 11, 2015 @03:54AM
(#10716054)
At Virginia Key? It's subsiding at about 0.17±0.09mm/year, says http://www.fsbpa.com/documents/Florida%20Sea%20Level_rev0404... . "This very preliminary value ... with its very large uncertainty ... should be viewed very cautiously, but a sinking Florida is in general agreement with geophysical models of Earth’s changing shape due to post-glacial rebound from the last ice age."
But the relative rise (same reference, and with a longer baseline) for Miami Beach is 2.4mm/year, so more than 10x faster than can be explained by subsidence.
(Also, unlike parts of the US which are sinking due to overpumping from an aquifer, in coastal Florida, seawater will fill in the parts of the freshwater lens which were overpumped. And while the Miami metro area pulls water from the Biscayne aquifer, the relative sea level rise is pretty consistent across Florida, including Cedar Key, which is a relatively isolated location with low population.)
Indeed, that's why the data set for this NYT article and my earlier URL to the report describing a sinking Florida only starts in the late 1990s - that's when the CORS sites (see http://www.ngs.noaa.gov/CORS/ ) were set up to give absolute positions based on satellite positioning.
There has been no land subsidence at all, apparently.
But the relative rise (same reference, and with a longer baseline) for Miami Beach is 2.4mm/year, so more than 10x faster than can be explained by subsidence.
(Also, unlike parts of the US which are sinking due to overpumping from an aquifer, in coastal Florida, seawater will fill in the parts of the freshwater lens which were overpumped. And while the Miami metro area pulls water from the Biscayne aquifer, the relative sea level rise is pretty consistent across Florida, including Cedar Key, which is a relatively isolated location with low population.)
The NYT piece references http://www.rsmas.miami.edu/blog/2014/10/03/sea-level-rise-in... which in turn points to http://tidesandcurrents.noaa.gov/stationhome.html?id=8723214 as the measurement source. That shows that the numbers are given with respect to NAVD88, and not some relative sea level to a survey point on land.
Indeed, that's why the data set for this NYT article and my earlier URL to the report describing a sinking Florida only starts in the late 1990s - that's when the CORS sites (see http://www.ngs.noaa.gov/CORS/ ) were set up to give absolute positions based on satellite positioning.