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Re: Rising sea levels are going to mess with the internet


From: Rob McEwen <rob () invaluement com>
Date: Thu, 26 Jul 2018 17:45:08 -0400

On 7/26/2018 4:22 PM, valdis.kletnieks () 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: https://insideclimatenews.org/content/average-global-sea-level-rise-1993-2017)

--
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



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