Friday, October 16, 2015

The Extinction of Philadelphia

Fig. 1
Regular reader and commenter, Tom, requested a graph or two of Philadelphia related SLC a while back.

He was intrigued that Philly had a sea port, as was I, so today that happens just in case he was feeling left out of the equation (Fig. 1, Fig. 2, Fig. 3, Fig. 4, and Fig. 5).

These "extinction of" type posts focus on records of tide gauges, and therefore sea level change (SLC) that is impacting specific cities.

Cities where sea ports are an endangered species (e.g. The Extinction of Washington, D.C.).

Their sea ports are an endangered species and are going to go extinct (The Extinction of Robust Sea Ports).

Regular readers know about the Dredd Blog software model which uses historical data from relevant tide gauge stations around the world, then appends acceleration-logic-data onto that historical data stream, thus creating a continuum of sorts, going on out into the future.

The term "tide gauge" may be a bit misleading, in the sense of tending to undervalue them:
"The term "tide gauge" is really a bit of a misnomer in current usage,
Fig. 2
since the instruments actually measure changes in sea level rather than just tides, which are only one contributor to sea level fluctuation. Because tides are now well understood their contribution can be accounted for, thereby permitting accurate observation of sea level variability and change attributable to other causes."
(NOAA Ocean Climate Observation Program, emphasis added). Add to that the fact Dredd Blog uses PSMSL data, which is well respected.

Like the "Eugenics Bug" that generated madness within the scientific community, the
Fig. 3
tide gauge bug went through a fantasy science phase, where the imagination was driven by an erroneous assumption, and was driven off the road into the jungle of error upon error.

The published works of Newton (B.C.E.) and Woodward (1888) were forgotten, ignored, or unknown to scientists who diagnosed tide gauges as being some kind of mystical mechanical liars.

Having a grasp of the reality of the impact of gravity of various sorts on SLC would have spared them the embarrassment (The Gravity of Sea Level Change).

To drive that point home, I will link to a study that was conducted without a mention of the impact of gravity of any kind, especially ice sheet gravity (Study, PDF).

Fig. 4
It is linked to so that you can see how even capable scientists can go off on a tangent, and begin to analyze good data thinking it is defective and in need of "data reconstruction" (ibid).

That study tries to be fair, but fairness does not replace acute awareness.

IMO, it demonstrates how "data reconstruction" is to be avoided because, for one thing it is play pretend.

Fig. 5
We know that the rate of SLC, as well as the type of SLC, whether sea level fall (SLF) or sea level rise (SLR), depends on proximity to ice sheets or glaciers.

Gravitational impact on SLC by large ice masses must be factored in, especially as they melt and disintegrate due to global warming (Proof of Concept - 3).

Tide gauge data, when left alone, is useful for many good reasons, so, let's not throw the baby out with the bathwater.

BTW, I have changed my mind on the 2, 3, and 5 year doubling logic in the model because it produces unrealistic projections (e.g. all ice sheets in Greenland and Antarctica melting completely before 2100).

So, I have replaced them with a 15 yr acceleration, so, now the acceleration rates projected will be 7, 10, 15, 20, and 25 yr degrees of acceleration as shown by the Philly graphs today.

Have a good weekend.


  1. Thanks Dredd. Like many other aspects of climate change, SLC can occur "abruptly."
    i appreciate how the various graphs skyrocket after 2055, but long before that i think Philly will cease to be a port, due to being under at least 3 additional feet of water than it is now. Looking at the 15 yr chart, it looks like that could be in the next few years.


    1. I am still calibrating it.

      The historical portion, and its pattern, have an impact that has not completely been worked out yet.

      I expect a 1m / 3ft higher SL, over the 1750 level, all along the East Coast by circa 2031 (~15 yrs).

    2. Philly is an east coast relative low point.

      As of 2014 it registered a 0.326m / 1.07 ft SLR over the 1750 level (in the historical PSMSL database).

      The 7yr graph (Fig. 5) shows SL reaching 1m / 3 ft circa 2038-39.

    3. NY (The Battery), for example, begins @ 0.446m, 1.46 ft.