“There Are No Facts About the Future”

This wonderful quote comes from Don Swanson, scientist emeritus at the United States Geological Survey’s Hawaiian Volcano Observatory as he speculates about the future of the lava lake which has just disappeared from Hawaii’s Kilauea Volcano. This post is about science, however, not volcanoes.

“The Science is Settled.” We hear that all the time. However, the science of the future can never be settled until the future has become the past. Let’s look at some examples,

The Science of the MMR Vaccine

We can say that “the science is settled” about the effectiveness of the MMR (measles, mumps, and rubella) vaccine because it has a history. From the website of the Centers for Disease Control:

“Before the measles vaccination program started in 1963, an estimated 3 to 4 million people got measles each year in the United States. Of these, approximately 500,000 cases were reported each year to CDC; of these, 400 to 500 died, 48,000 were hospitalized, and 1,000 developed encephalitis (brain swelling) from measles. Since then, widespread use of measles virus-containing vaccine has led to a greater than 99% reduction in measles cases compared with the pre-vaccine era.”

What about safety? There is a concern that the MMR vaccine causes autism; this could’ve started because the first signs of autism usually happen at about the same age as vaccine is administered. Facts from the past to the rescue: the vaccine has been in use for a long time; there are probably more studies of its link to autism than were needed. There is no link. The science is settled. I think this vaccine along with several others should be mandatory.

However, extravagant claims set off the BS alarms even in reasonable people. No vaccine is perfectly safe. Some people are allergic to every vaccine. People with compromised immune systems should not usually be vaccinated. A septic needle can cause disease no matter what its payload.  History tells us that the risk of NOT taking the MMR vaccine is much worse than the risk of taking it, unless you are trying to freeload on the fact that everyone else is vaccinated. We must make the vaccine mandatory to avoid freeloaders putting other people at risk. Our claims must be credible to convince the public to agree to make something as intrusive as a shot mandatory. If we misuse the phrase “the science is settled”, we reduce faith in scientific evidence.

The Science of Planetary Motion and Relativity

Isaac Newton published his Philosophiæ Naturalis Principia Mathematica in 1687. It was a compendium of theories about motion and gravity. It upset the “settled science” of its time. Edmond Halley used Newton’s theory to predict the comet later named after him would reappear in 1758. He wasn’t alive to see it, but the accuracy of this prediction helped to make Newton’s laws of gravity “settled science”. Theories usually can’t actually be proven although they can be disproven. If the comet had come back on a different schedule, it would have cast severe doubt on Newton’s theories. Many predictions are made with Newton’s laws and they work – except when they don’t.

Newton’s Laws are based on observations of the universe as we usually see it. They are useful for describing that universe and predicting its behavior. In 1916 Albert Einstein published his theory of general relativity which asserted that the universe is not as Newton saw it. This theory wasn’t accepted until a spectacular prediction he made that light rays are bent by gravity was verified during the solar eclipse of 1919 (and many times afterwards). The verification made Einstein a cultural phenomenon because he not only predicted that the light waves would curve but by how much. General relativity became settled science by making a series of predictions and having none of them falsified.  It is useful in astronomy, electronics, navigation – lots of stuff we do.

Except, to Einstein’s dismay, relativity doesn’t work at the quantum level. The settled science of one era becomes just an approximation (or a mistake) as we make finer observations.

The Science of Evolution

Darwin’s theory of the evolution of species was anything but settled science when he first published it. Supporting it was very bad for your ecclesiastical or academic career. Implicitly, the theory predicts that the fossil record (facts from the past) will show a progression of species. A species in this context are generally defined as a population of animals which cannot interbreed with members of a different species. The fact that selective breeding can produce variations within a species was already well known and did not demonstrate that new species could arise without divine intervention.

In general the fossil record does include old species which have since disappeared and new species similar to them which have appeared later. What the fossil record does not show clearly are the transitional creatures. Darwin imagined evolution as steady continuous process. But then why do there appear to be clean breaks between species in the fossils we’ve found? This questioning was good for the theory of evolution. It led to a new hypothesis that evolution consists of periods of relative stability followed by a very fast evolution to a new stasis. This is called punctuated equilibrium and is consistent with the geological finding that catastrophes are often abrupt – including climate change. In populations which are well adapted to their current environment, a random mutation is much less likely to be helpful than in an environment which has suddenly changed. If species change is abrupt in response to environmental change, then we’d expect to find very few transitional creatures. Only a tiny part of any population survives as a fossil. Questioning Darwin’s view of evolution led to an improved theory that better comported with the facts of the past.

Since Darwin we have discovered genes as the mechanism of evolution (he didn’t know about genes). We know how genes mutate. We can even force them to mutate ourselves. We can create new species (scary thought). The general theory of how species evolve is considered “settled science”. We don’t need divine intervention to get new species (although we can’t prove divine intervention didn’t happen). But there are exceptions to evolution as Darwin saw it besides its punctuated nature. Turns out genes can be swapped between species outside a laboratory, for example. Even though I am convinced that species evolve for natural reasons and will continue to evolve, I know that evolutionary theory will continual to evolve as well. The science of complex events is never quite settled. Which brings us to…

The Science of Climate Change

What’s “settled”? Climate changes; always has and would be surprising if it stopped – even if every well-intended high schooler in the US goes on strike. It’s gotten a lot warmer since the glaciers began to melt and the sea has risen as the ice melted. You can’t walk from Siberia to Alaska or Norway to Scotland any more. This warming actually peaked about 7000 years ago and started a gentle decline which reached its minimum about 200 years ago (see Marcott et al). Temperatures have been generally rising since then and we are near but not at the 7000-year-old peak. These are facts about the past that are reasonably well established, although there is some room for dispute around exact interpretation of the circumstantial evidence and whether there has been warming in the last decade or so.

What is not known, no matter how inconvenient our lack of knowledge, is what is going to happen next with the climate. Since we don’t fully understand what made climate change in the past, it is hubris to say we know how it will change in the future. For example, we do know (fact from the past), that rising temperatures were accompanied by rising atmospheric CO₂ levels. We also know that rising temperatures cause CO₂ to be released from formerly frozen soil AND that, all things being equal (which they never are) more CO₂ in the atmosphere will cause the earth to retain more solar heat. Did the increased CO₂ levels cause the warming? Did the warming increase the CO₂ levels? Or are both true, which is certainly possible. If both are true, there would be a feedback loop in which the earth would continue to heat up. This is the nightmare that many fear from current climate change. It’s not an impossible scenario.

There is a wealth of computer models which predict this nightmare; the UN predictions are based on them. But, unless there are bugs in the computer code, models written with the same assumptions will produce the same results; so having computers vote is not science. We won’t know if the assumptions are correct until the predictions they make, like Einstein’s predictions from relativity, actually come true (and even then it could be coincidence or only partly cause and effect). If we wait to see if the predictions are falsified, many say, it may be too late for us to act to reduce anthropogenic (man-made) emissions of greenhouse gasses, particularly if there is a tipping point after which the heating cycle is runaway.

According to “The Holocene temperature conundrum”  published in the Proceedings of the National Academy of Sciences which has been peer-reviewed and written by properly credentialed scientists, the most cited models predict that temperatures would have continued increasing 7000 years ago because of increasing greenhouse gasses and other feedback loops; but temperatures decreased. Why? Maybe there’s a good reason which doesn’t apply any more for the divergence between prediction and fact. Maybe the models are wrong.

There is a recent article in Nature in which respectable scientists say that variations in solar activity account for most climate change on earth and they cite correlations between solar magnetic cycles and earthly temperatures. Are they right? We don’t know. They also make predictions, but fortunately their predictions are for the very near-term future. They say a short-term cooling trend should start in 2020 and continue until 2035. We’ll see very quickly if they are right. But, even if they’re right, it’s not reassuring. They then predict that temperatures will keep rising, with small respites, until 2600. The difference between their prediction and the politically correct consensus that climate is mainly forced by anthropogenic activity is that, if the solar-cycle people are right, we’re not going to change the temperature no matter how many Teslas we buy; we’ll have to start mitigating the damage by moving out of flood zones and farming newly-thawed soil.

Since the threat of climate change, whether preventable or not, is existential, we need to understand climate much better than we do. Understanding is not reached by propagandizing, name-calling, and sensationalism. Fortunately modern technology CAN give us much better understanding of whether and how the earth is warming and the feedback loops involved. One thing we need is a fleet of mini-satellites measuring how much radiation is reaching the earth from the sun and how much is leaving. This data won’t tell us exactly how the earth’s complex systems will react to more or less net solar radiation retained but it will help us much better understand the effect of greenhouse gasses and how action we might take will affect the energy budget. It will indicate whether the earth quickly radiates extra heat away and how much it is retaining. Prototypes of these satellites exist.  Why we don’t have a moonshot program to perfect and launch them is beyond me. We can gather facts about the present.

Perhaps politicians on both sides of the climate issue (as if it had sides in anything but the political realm) are afraid of answers from anywhere but twitter. Perhaps we’d rather just argue with each other and call each other names like alarmist and skeptic. We need facts. Claims that “the science is settled” are not helpful. If the science of climate is “settled”, no more study is needed. There is nothing that needs further study more than climatology.

More on evolution at https://blog.tomevslin.com/evolution/

More on climate at https://blog.tomevslin.com/global_warming/