Monday, November 23, 2015

The Evolution of Models - 17

Fig. 1

I finally found an insidious bug and squished it, because it had been squishing my brain for several days.

I pointed out some of the exercises involved in this project in the last post of this series (The Evolution of Models - 16).

I had been doing a thing using global mean sea level (GMSL) as calculated by the Commonwealth Scientific and Industrial Research Organisation (CSIRO).

They keep GMSL records going back to 1880.

Add to that the global mean surface temperature (GMST) as calculated by the Goddard Institute for Space Studies (GISS).

They keep GMST records going back to 1880.

Fig. 2
The task I was working on was to combine all that within a meaningful relation to the records of a single Permanent Service for Mean Sea Level (PSMSL) tide gauge station.

Meaning, displaying the GMSL, the GMST, and one local tide gauge station history in a single graph (e.g. Fig. 1) in terms of a pattern relation between each and every one them.

The difficulty is doing it with the high Hansen projection, as well as the low The Intergovernmental Panel on Climate Change (IPCC) projection, in the same graph.

I did the low IPCC projection part of it (Fig. 1), but I am not yet satisfied with the outcome of the larger scale projection.

Fig. 3
The problem is that the IPCC and Hansen projection numbers are so far apart (e.g. ~15 ft. or more by 2100, compared to ~3 ft. by 2100).

It will take a bit longer, but it will eventually work out and be better than just one tide gauge station display by itself (e.g. Fig. 3).

BTW, the Hansen model (Fig. 2) is looking to be the one to watch IMO, because lately the months and years are breaking global heat records one after the other in a big way.

Something has to give.

My bet is that "the give" will be the collapse of ice shelves that are now holding back the ice streams of the ice sheets in Greenland and Antarctica.

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


  1. Good work, Dredd. i agree with your analysis too - all that heat is only going to increase ice melt and add water to the ocean (while expanding the ocean thermally at the same time) leading to SLR "faster than expected."


    1. Right on Tom.

      It is not how much square area the ice shelves cover, it is how thick they are in terms of being able to hold back the ice streams of the ice sheet.

      They are getting thinner even if they are covering more square footage of surface.