Tuesday, July 22, 2014

Global Warming Links #2

Second up, a set of articles concerning the ENSO and global warming
El Niño Southern Oscillation, or ENSO, refers to the effects of a band of sea surface temperatures which are anomalously warm or cold for long periods of time that develops off the western coast of South America and causes climatic changes across the tropics and subtropics. The Walker Circulation was discovered by Gilbert Walker at the turn of the 20th century. The 'Southern Oscillation' refers to variations in the temperature of the surface of the tropical eastern Pacific Ocean (warming and cooling known as El Niño and La Niña, respectively) and in air surface pressure in the tropical western Pacific. The two variations are coupled: the warm oceanic phase, El Niño, accompanies high air surface pressure in the western Pacific, while the cold phase, La Niña, accompanies low air surface pressure in the western Pacific. Mechanisms that cause the oscillation remain under study.
"Under study" means that no one know what causes them.

Article: Recent slowdown in atmospheric warming thanks to La Niña

There appears to be correlation between el Nino events and warming, and la Nina events and cooling (or, at least, a pause in warming). The hottest year in modern record keeping (if you discount the 1930's) coincided with a major el Nino event.

Climate modeling. Some problems with this research.They took a standard climate model that failed to predict the current hiatus, then modified it and compared the results. "The [modified] version used these same inputs but also forced the model to use the actual sea surface temperatures in the equatorial Pacific rather than letting the model itself generate them."

In other words, they put in cooler sea surface temperatures for the equatorial Pacific and found that the model "predicted" cooler surface temperatures on earth. If you force your model to run on low temperatures, of course it is going to predict lower temperatures.

Now, they do make a testable prediction: that when we have a run of el Nino events in the future, global warming will return.

However, this is still a "correlation does not equal causation" logical fallacy. Just because the events are coincidental is not proof of causation.
It adds up to a pretty coherent picture pointing to a cluster of La Niñas as the cause of the slowdown in atmospheric warming. But why all the La Niñas? The researchers chalk it up to natural variability....
Except the Wikipedia article referenced above (with its accompanying graph) makes it clear that it is the el Nino events that are increasing in size and frequency.
Also in accordance with reality, energy trapped by greenhouse gases continued to increase in the model, with ocean heat content rising apace. The modeled climate system didn’t cease warming; it just didn’t show up strongly in the atmosphere.
Except it did not end up in the ocean. See the posting below.

Article: Lewandowsky and Oreskes Are Co-Authors of a Paper about ENSO, Climate Models and Sea Surface Temperature Trends (Go Figure!)

The author of this article rips into the Lewandowsky article for "a number of curiosities."

The first one is that the authors cherry-pick climate models that match the hypothesis (that is, selecting the results to prove the hypothesis). As Arthur Canon Doyle has Sherlock Holmes say, "It is a capital mistake to theorize before one has data.  Insensibly one begins to twist facts to suit theories, instead of theories to suit facts."

Another "curiosity" is that after choosing the "best" and "worst" models, the authors do not actually say whose models. So that not only do they chose models that best fit their conclusions, but refuse to tell whose models they chose so that they cannot be tested independently.

This lack of transparency is means that their research cannot be checked, cannot be reproduced, and can neither be confirmed or refuted.

Additionally, THE ACTUAL AUTHORS OF THE MODELS can not comment on how their own models are being used.

It is not science to make statements that cannot be tested.

It is the classic "appeal to authority" logical fallacy. "We are scientists; what we say must be taken as true on the basis of our authority."

A third curiosity is that the four "best" models fit 15 years of the hiatus and simulate ENSO. However, out of dozens of models, they found 4 that "work" and they work for a 15-year period. There is not mention of whether or not they work for longer periods of time (and all models have much longer than 15 years of running time.)

In other words, it is another appearance of the "correlation is not causation" logical fallacy. Just because four (out of dozens) work for 15 years does not actually show causation.

There are several other curiosities. However, I am going to end here

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