Friday, April 24, 2015

The Evolution of Models - 7

Fig. 1 (click to enlarge)
You will be glad to hear that this [may be] the last post in this series.

I have now accomplished all I wanted to, conceptionally, with the sea level rise (SLR) calculation software program.

After jettisoning the Potsdam Institute hypothesis (reasons here), I have  settled on Dr. James Hansen's "doubling logic" and implemented it because what he wrote about "doubling time" is just another way of saying "acceleration."

What I am talking about is the dynamics at play with his statement:
The increasing Greenland mass loss ... can be fit just as well by exponentially increasing annual mass loss, a behavior that Hansen (2005, 2007) argues could occur because of multiple amplifying feedbacks as an ice sheet begins to disintegrate. A 10-year doubling time would lead to 1 meter sea level rise by 2067 ... 2045 ... for 5-year doubling time and 2055 ... for a 7-year doubling time.
(Hansen on SLR, emphasis added). Fig. 1 is a graph generated from data set to simulate the 10 year doubling, Fig. 2 is the 7 year doubling, and Fig. 3 is the 5 year doubling:
(5-yr doubling)

Year, Non-Polar, Antarctica, Greenland, Combined
2044, 0.342175, 1.2416, 1.38612, 2.96989
2045, 0.367532, 1.30524, 1.4234, 3.09617
2046, 0.390356, 1.36424, 1.45572, 3.21032
2047, 0.414552, 1.42324, 1.48805, 3.32584

(7-yr doubling)

Year, Non-Polar, Antarctica, Greenland, Combined
2054, 0.415827, 1.31789, 1.20701, 2.94072
2055, 0.435562, 1.36373, 1.22946, 3.02875
2056, 0.456725, 1.41347, 1.25455, 3.12474
2057, 0.47646, 1.4593, 1.27701, 3.21277

(10-yr doubling)

Year, Non-Polar, Antarctica, Greenland, Combined
2066, 0.496188, 1.38763, 1.06151, 2.94533
2067, 0.508463, 1.42316, 1.07847, 3.0101
2068, 0.523848, 1.45869, 1.09543, 3.07797
2069, 0.539233, 1.49422, 1.11239, 3.14585
The software still simulates the delays, lags, the zones, acceleration, and uses the data
Fig. 2 (click to enlarge)
file to determine that performance.

For those who think Dr. Hansen is too conservative with his estimations about when the 1 m / 3 ft. SLR will take place, simple adjustments to acceleration rates in the data will generate a different .csv file and graph.

Likewise, for those like Cato The Wise who are paid to think Dr. Hansen is exaggerating, or exhibiting hubris, simple adjustments to the data will generate a different .csv file and graph that would make even the High Priest of Denial ooze self-righteousness.

Fig. 3 (click to enlarge)
The point is that I reached the flexibility I was initially shooting for, and now I can get back to tracking the Cryosat-2 and GRACE data as it is published.

My bet is that Dr. Hansen will prove to be the most aware of what is going on.

BTW, the Dredd Blog SLR software I have developed in this series is going to be placed under a Creative Commons, or similar licensing grant, so that anyone interested in SLR can use it freely.

All I have to do is write the user manual, and then I can move on back to harassing gummit officials who deny climate change.

Regular reader Tom provided a link to a documentary, which I am embedding below with today's post.

Have a good weekend.

The next post in this series is here, the previous post in this series is here.

Hopium, Inc. does some secular praying, forgetting to mention that the cheap way out is to leave the fossil fuels in the ground:


  1. This project is important Dredd, and you're leading the way man. Here's a story from the edge of your topic.

    Sea-Level Rise Poses Hard Choice for Two Neighborhoods: Rebuild or Retreat?


    1. Yeah.

      I even got Greenland to be represented by the green graph line on the latest graphs. ;)

  2. Tom,

    Very interesting link.

    A subtitle could be "to ground-hog day it or not?" (link