Federico Pistono

This is a post in response to Jodi's and Vitezslav's articles.

Jodi makes a valid point, that is, generally speaking. But I feel like she is missing something in the picture. While it is true that "continually re-examining the evidence can only ever strengthen our understanding of what we're dealing with", the reasons for being an outcast or a sceptic 30 years ago had profound scientific reasons.

The amount of data that we had was absolutely inadequate for the kind of research that we were trying to pursue. As more data comes in, you are more likely to reach a conclusion that is more likely to be true, or close enough. The kind of general relativism "We can all be wrong, you never know" and so on is partially true, but it fails to consider the actual evidence in face of a scientific and cultural revolution.

Consider the birth of quantum mechanics. When Werner Heisenberg proposed the "uncertainty principle", that is, it's impossible to measure simultaneously both position and velocity of a microscopic particle with any degree of accuracy or certainty, it had profound implications for such fundamental notions as causality and the determination of the future behaviour of an atomic particle.

Werner Heisenberg formulated the uncertainty principle in, ironically, the Niels Bohr's institute at Copenhagen, while working on the mathematical foundations of quantum mechanics.

This seemingly harmless sounding statement had even more profound scientific and philosophical implications. Albert Einstein was repelled by the idea that the universe was non deterministic, and he spent much of his late years trying to disprove quantum theory. He firmly stood by the idea that randomness is a reflection of our ignorance of some fundamental property of reality, while Niels Bohr's posistion was that the probability distributions are fundamental and irreducible, and depend on which measurements we choose to perform. Einstein and Bohr debated the uncertainty principle for many years.

Today, most physicists accept the laws of quantum mechanics as an accurate description of the subatomic world. And certainly it was a thorough understanding of these new laws which helped Bardeen, Brattain, and Shockley invent the transistor.

In short, Einstein and all the other sceptics were wrong, and all the observational evidence that we collected points to the direction of quantum theory. There may be a few sceptics, but nobody would dream of going back to Newtonian mechanics, they would most likely formulate a third theory, a new idea. Progress, not regress.

Science evolves, it ameliorates its tools for measuring and its knowledge of the physical world. The amount of data that was collected in the 70's regarding our climate, the models and the simulations were extremely poor. Now we have a multitude of data coming from multiple sources, including satellites, powerful computers and complex algorithms that can predict with a certain degree of accuracy the near future.

In other words, we held a position like a religious belief when we were completely ignorant, now we have a little more knowledge and we can discard old dogmas and opinions in favour of observational science and probabilistic predictions.

If you don't have to time/will to read the extensive scientific research in support of the current climate change theory, I suggest you watch this wonderful series of documentaries by Iain Simpson Stewart, a Scottish geologist, Professor of Geoscience Communication at the University of Plymouth, and produced by the BBC entitled "Earth: The Climate Wars" (thanks to TDF for the following description).

Episode 1 – The Battle Begins

In the 1970s the world seemed to be falling apart. From acid rain to overpopulation, ecological concerns were at the fore. And it was at this time that climate change first became a hot political issue. But it wasn’t global warming that frightened scientists, it was the complete opposite; a new ice age.Dr Iain Stewart traces the history of climate change from its very beginning and examines just how the scientific community managed to get it so very wrong back in the Seventies. Along the way he uncovers some of the great unsung heroes of climate change science, and introduces us to a secret organisation of American government scientists, known as Jason, who wrote the first official report on global warming as far back as 1979.He shows how – by the late 1980s – global warming had already become a serious political issue. It looked as if the world was uniting to take action. But it turned out to be a false dawn. Because in the 1990s global warming would be transformed into one of the biggest scientific controversies of our age.

Episode 2 – Fightback

Dr Iain Stewart investigates the counter attack that was launched by the global warming sceptics in the 1990s. At the start of the 1990s it seemed the world was united. At the Rio Earth summit the world signed up to a programme of action to start tackling climate change. Even George Bush was there. But the consensus didn’t last.Iain examines the scientific arguments that developed as the global warming sceptics took on the climate change consensus. The sceptics attacked almost everything that scientists held to be true. They argued that the planet wasn’t warming up, that even if it was it was nothing unusual, and certainly whatever was happening to the climate was nothing to do with human emissions of greenhouse gases.Iain interviews some of the key global warming sceptics, and discovers how their positions have changed over time.

Episode 3 – New Challenges

Having explained the science behind global warming, and addressed the arguments of the climate change sceptics earlier in the series, in this third and final part Dr Iain Stewart looks at the biggest challenge now facing climate scientists. Just how can they predict exactly what changes global warming will bring? It’s a journey that takes him from early attempts to model the climate system with dishpans, to supercomputers, and to the frontline of climate research today: Greenland. Most worryingly he discovers that scientists are becoming increasingly concerned that their models are actually underestimating the speed of changes already underway.

As for Vitezslav's remark:

Later, in reply to my question, he also said, that climate sceptic scientists are "flat earthers" and it is a waste of time to have an "open discussion" with madmen.

[...]

So first they invite us, they pay a hotel, airplane and food for us. It costs thousands of EUR. We fly here from all parts of the world. To an event called "Think about it". And then we are told "NOT TO think about it". So now I am not sure what to do. Should I use my head or not? Advise me.

[...]

Maybe most scientists really do believe so (I doubt it), but it is just a belief. They do not have the evidence. Not yet. You may think, that "we must act fast, we cannot wait for the scientific evidence". OK, but then you cannot say it is a "science based policy", can you? And there is no reason to ridicule sceptics as flat earthers and say the matter is "closed".

I'm very much curious of his position. He says that many scientists hold their beliefs on human caused climate change, that there is no clear evidence and that after all, it's just a belief.

It could not be farther away from the truth.

Real scientists do no hold any belief. They observe something, and by following the scientific process they know something is likely to be true, or accurate. That is, until new evidence and/or a new consistent theory emerges, which refines or discards the old theory.

From what I understand he wants to put the emphasis on the effect that solar radiations may have on our climate, specifically to various solar cycles that seem to occur overy few years.

According to the excellent guide: "How to Talk to a Climate Skeptic: Responses to the most common skeptical arguments on global warming" there a five stages of denials, each one of them having several subsections. Vitezslav seems to be at number 1.a.

However, to be fair, he does point out the Suess and Hallstadtzeit cycle, a few of the cyclic changes in behaviour of the Sun. Many possible patterns have been suggested. Interestingly, only the 11 (Schwabe) and 22 year (Hale cycle) cycles are clear in the observations. The Gleissberg, Suess, Hallstatt, and the Xapsos-Burke cycle are still in the realm of what Vitezslav himself would call "belief", since there is no clear observational evidence.

The climate sceptic guide, however, helps us again:

It's true that the earth is warmed, for all practical purposes, entirely by solar radiation, so if the temperature is going up or down, the sun is a reasonable place to seek the cause.

Turns out it's more complicated than one might think to detect and measure changes in the amount or type of sunshine reaching the earth. Detectors on the ground are susceptible to all kinds of interference from the atmosphere -- after all, one cloud passing overhead can cause a shiver on an otherwise warm day, but not because the sun itself changed. The best way to detect changes in the output of the sun -- versus changes in the radiation reaching the earth's surface through clouds, smoke, dust, or pollution -- is by taking readings from space.

This is a job for satellites. According to PMOD at the World Radiation Center there has been no increase in solar irradiance since at least 1978, when satellite observations began. This means that for the last thirty years, while the temperature has been rising fastest, the sun has not changed.

There has been work done reconstructing the solar irradiance record over the last century, before satellites were available. According to the Max Planck Institute, where this work is being done, there has been no increase in solar irradiance since around 1940.

This reconstruction does show an increase in the first part of the 20th century, which coincides with the warming from around 1900 until the 1940s. It's not enough to explain all the warming from those years, but it is responsible for a large portion. See this chart of observed temperature, modelled temperature, and variations in the major forcings that contributed to 20th century climate.

RealClimate has a couple of detailed discussions on what we can conclude about solar forcing and how science reached those conclusions. Read them here and here.

p.s. This article was crossposted on the TH!NK ABOUT IT - Climate Change blogging competition.