Rising sea levels are going to mess with the internet

Rob McEwen rob at invaluement.com
Thu Jul 26 21:45:08 UTC 2018

On 7/26/2018 4:22 PM, valdis.kletnieks at vt.edu wrote:
> Let's run the math.  1mm/additional per year. So 1 the first year, 2 aditional
> the second, ... and the century year then adds 100mm or 4 inches*by itself*.
> But we need to add years 1 to 99's contributions too...
> sum(1..100) = 101 * 50 or 5050mm.  Divide by 25.4 and you get 198 inches
> cumula

You misinterpreted what I said. I was merely saying that the current 
yearly increase is about 1 mm more than the yearly increase was from 40 
years ago. (But maybe not even that much!) I was NOT saying that each 
year was increasing by a rate that was mm more than the previous year.

Your calculation is based on year-to-year acceleration of growth. In 
fact, that year-to-year /*acceleration*/ of rising sea levels is 
actually a ~0.025 mm average increase over the previous year. (this is 
HALF the thickness of a single sheet of paper!) So try your calculation 
again - except see how impressive that "compound interest" you talk 
about is when the year-to-year acceleration of growth over the previous 
year is only 0.025 mm.

ALSO - I say "average rate of increase" because the graph is not a 
smooth line. Like almost everything, it is jagged - where some years 
show signs of more rapid acceleration, and other years show a decrease 
in acceleration, or even a lowering of the sea levels. Anytime one of 
the other hits a historical extreme, it raises curiosity that we might 
be in the middle of a fundamental shift to a "new normal". But before 
anyone assumes that we're about to hit a new normal where that .025 mm 
year-to-year increase in the rate of rising - is about to accelerate - 
note that, in fact, the sea levels have actually LOWERED in the past 
couple of years. (not just rising less fast - ACTUALLY LOWERING). (see 
blue line at the end of this graph: 

Rob McEwen
+1 (478) 475-9032

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