Can this AGW hypothesis be falsified?

Part 1: “Human actions, most specifically our burning of fossil fuels, is leading to significant climate alterations, including but not limited to a significant rise in the average temperatures of the atmosphere, near surface, and oceans.”

This can not be falsified as it’s governed by fundamental laws of science, notably quantum mechanics and thermodynamics. Some people might not like this, they may not even accept it, but the inalienable fact of the matter is that it’s a universal and invariable certainty. Any attempt to dismiss it would mean dispensing with the laws that govern the structure and characteristics of the universe.

The use of the word ‘significant’ is of course open to interpretation. Some may feel that an increase of say 3°C in the average global temperature is significant whereas others may see this as only being a small increase. It depends on the larger context. If you’re talking in terms of timeframes of a few hundred years then it’s very significant, primarily because it represents the fastest ever change in global temperatures in the known history of the planet.

On the other hand, if you’re referencing such a temperature change in the context of say a full ice-age cycle then it’s a comparatively small change, representing as it does, about one tenth of the full cyclical temperature swing.

Part 2: “Further, this rise (I believe somewhere between 2 and 5 degrees a century, at present estimates) will cause significant disruptions to both natural systems and human social organizations if unchecked”

Again, we have the problem of quantification due to the inclusion of the term “significant disruption”. Only a fool would deny that there has already been some disruption consequent to a changing climate, whether this is construed as being beneficial, detrimental, significant or otherwise is perhaps more down to individual interpretation and exposure to consequence than anything else.

Due to a combination of atmospheric residence periods, global warming potentials, radiative forcings and volumetric concentrations of greenhouse gases coupled with more thermodynamics and QM, it is an unassailable fact that the underlying and running mean global temperature has to increase. Only the introduction or unforeseen enhancement of an opposing mechanism or consequence could negate this.

On the basis that such an event, whist having a very low probability, can’t be categorically ruled out, then there is potential for falsification of the claim but only insomuch as it would require the introduction of a concept alien to the original discussion.

The referencing to a rise of “between 2 and 5 degrees a century” can not be falsified because the statement has been qualified by stating “at present estimates” and is therefore factually correct. Given that these estimates may change in time and that real world observations in the future may be outwith these parameters, it may therefore transpire that the figures are indeed shown to be erroneous, but not in the context in which they are used here.

Given the nature and content of the text you quoted and that it isn’t well bounded or contextualised then provision for partial falsification exists.

Yes. In science a properly constructed hypothesis can be falsified if experimental evidence does not agree with its predictions. The hypothesis gives several predictions:

1. A significant rise in average temperature means a rise in temperature that is statistically discernible from the baseline with a confidence > .95. The hypothesis is not falsified by the temperature data.

2. Human use of fossil fuels is casually related to climate change. This part is easily tested by measuring the isotopic composition of atmospheric carbon dioxide. The hypothesis is not falsified by the isotopic data.

3. The temperature should rise between 2 and 5 degrees (K) per century. The observed rate of increase is consistent with the hypothesis. If the rate of increase were significantly lower in the next 3 decades, the hypothesis could be falsified.

3. The hypothesis can be falsified by showing that there are not significant disruptions to natural systems. If it can be shown that a majority of the earth's ecosystems have the same types of species in the same abundance as a pre-industrial reference period then there is no effect and the hypothesis is falsified. The evidence is that significant changes to ecosystems have already happened. The hypothesis is not falsified.

The AGW hypothesis does not make any predictions that cannot be tested and therefore is a good hypothesis.

It's a very large hypothesis, with quite a bit of conjecture, falling a bit outside of "science" as it's usually understood, and falling outside of any *one* particular field of science. Science is better at more plain hypotheses: an increase of x CO2 will cause y warming. And even then it's going to give you statistical averages, very hard to do with one planet -- we certainly could get hit with an asteroid or nuclear war that changes the climate and in reality falsifies an otherwise likely hypothesis, so with a sample size of 1, science can inform but can't prove/falsify a hypothesis.

There are limits to what science can tell us, which isn't going to mean that the warming is or isn't going to happen.

Each piece of that hypothesis seems supported by the underlying science from different fields... very basic physics of global warming that apply here or on Venus, to climate models that are very difficult but seem to be pulling in better predictions and much better predictions than any alternative (and there is no natural "null" hypothesis, neither "it is going to be bad" nor "it is not going to be bad" can be falsified till they happen -- your hypothesis is not working-science, the realm of working-science is to compare/falsify models based on what is currently happening); to wildly varied sciences trying to predict what will happen to us, our economy and the planet if warming does happen piece by piece.

You can see some of this reflected in which scientists agree with global warming theory in more overwhelming numbers: physicists have long thought it a threat where their science is very clear at the small scale of what is happening, climate models were toys in 1985 but now consistently the best models at predicting what is happening today (the currently falsifiable arena) also predict a hot future and so climatologists have been pouring over into agreement with the AGW predictions, and geologists who study the earth's history don't have a science that can easily work in falsifiable theories here -- this is the first example of CO2-led warming -- and thus people who approach science from this angle are among the most skeptical of scientists.

Sure, we're doing the definitive experiment right now. If we keep on doing nothing about our CO2 output and the climate stops warming the hypothesis will be falsified. It is, of course, a very expensive experiment, and every professional scientific society on earth is betting against falsification.

Yes and no because it depends on if we make the right decisions for the future or just look dully at the question it all depends on all the people in the world if we can make changes to what we do it can be proven wrong but that obviously isnt going to happen because of population growth and more cars sources of transportation more houses more electronics being made really and needed

First, it is a cumbersome and poorly defined hypothesis that contains a couple primary and several secondary questions (which all should be separate hypotheses).

If you mean does it meet the requirement of falsification, the answer is yes for some.

It is false if any of the following is false.

1) there is no increasing temperature trend;

2) there is no relationship between human activity and atmospheric CO2; or

3) there is no relationship between atmospheric CO2 and temperature.

The other major component, "...will cause significant disruptions to both natural systems and human social organizations if unchecked” although too broadly stated are areas of investigation derived from - and may be explained by - AGW Theory.

In fact, it is a no-brainer (there is ample evidence from paleoclimatology, paleontology, and archaeology of the effects of major climatic changes on environments and human adaptations) and is the primary reason people care about global warming.

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MIKE L --

And your answer looks like an arrogant response from someone who is scientifically illiterate - and is too intellectually lazy to care.

Yes , It looks like a arrogant guess from the silly IPCC.