Most people over the age of 35 years old will probably be able to agree with the statement that “you learn a lot of things in life, and you also forget a lot too”.
Things get replaced in your active memory as you move from phase to phase of your life, meet and lose people, as you change careers, take up new hobbies and interests.
For instance, I used to be able to speak German passably well, but this got replaced by Dutch, and now I don’t practice speaking Dutch at all, it’s faded from my skillset.
A lot of experiences cast shadows and are best totally forgotten. Others, which we consider valuable, we tend to summarise for ourselves and retain at least the outline of what we have known.
So it is, that although I used to know a fair bit about the study of Physics, or “Natural Philosophy”, these days I would struggle to do the Mathematics, or remember all the terms in the Maxwell equations for Electromagnetism.
However, I still retain a few “internal animations” about particle Physics, about how waves are particles and particles are waves and how light and other electromagnetic radiation interacts with matter.
These insights into sub-atomic scale effects are important in the study of Quantum Physics. For example, a very useful working model for an average atom includes the presence of a “shell” of electrons, that stop behaving like mere particles when surrounding a proton-neutron nucleus, but start to have a smeared impact over the whole interface area of the atom.
Any matter or light interacting with this atom would act as if the negatively charged electrons were more or less equally distributed over a whole sphere.
When they interact, the electric fields of the electron shell and the electric field of the light cause the “energy level” of the shell to change.
If you can picture it, it’s like a balloon being given an extra puff to expand slightly. This increases the pressure inside the balloon, with the tendency for the extra puff to be re-emitted and the balloon to go back to its “normal” size.
I’m a bit of a philosopher naturally, and I see in this picture something fractal, something tiny that says something similar about the state of the whole Earth.
The Earth acts as one. It has an average spectrum of emissions of electromagnetic radiation, and this is being shifted by the recent phase of enhanced Global Warming – as more Greenhouse Gas gets pumped into the air above us, the Earth is warming up inside this envelope, and this changes the colours of light and other electromagnetic radiation detectable by satellites monitoring the Atmosphere.
The Earth acts almost like the tiny atom that has had its electron shell puffed out – the Atmosphere is reacting to the general warming – parts of this envelope are being pushed out. It’s one of the fingerprints of Global Warming :-
“Some of Santer’s more recent work, for instance, addresses changes in the height of the tropopause — the boundary between the troposphere, the more turbulent lower layer of Earth’s atmosphere, and the more stable stratosphere above. (Between 5 and 10 miles above the Earth’s surface, evidence of the tropopause can be seen in the flat, anvil-like top of a thundercloud.) Measurements over the course of several recent decades have shown that the tropopause has risen markedly. By studying tropopause changes in computer climate models, then comparing model output with actual observations, Santer was able to show that both the warming of the lower atmosphere and cooling of the stratosphere led to a rise in the height of the tropopause — and that the observed rise matched the fingerprint of an increase in heat-trapping gases. “Nobody had looked at it before,” Santer says. “But the data showed clearly that natural causes alone simply could not provide a convincing explanation for the observed change.” All the climate fingerprinting research to date, has arrived at the same conclusion, says Santer; namely, that “natural causes cannot provide a convincing explanation for the particular patterns of climate change we see.” That, he says, is why scientists “have come to have such confidence in our understanding of what is happening — not because of the claims of any one individual, but because of the breadth of scientific work and reproducibility of the results.”…”
“While early fingerprint work dealt almost exclusively with changes in nearsurface or atmospheric temperature, more recent studies have applied fingerprint methods to a range of different variables, such as ocean heat content, Atlantic salinity changes, sea-level pressure, tropopause height, zonal-mean rainfall, surface humidity, atmospheric moisture, and Arctic sea ice extent. The general conclusion is that for each of these variables, natural causes alone cannot explain the observed climate changes over the second half of the 20th century. The best statistical explanation of the observed climate changes invariably involves a large human contribution…Over the last century, we have observed large and coherent changes in many different aspects of Earth’s climate. The oceans and land surface have warmed. Atmospheric moisture has increased. Glaciers have retreated over most of the globe. Sea level has risen. Snow and sea-ice extent have decreased in the Northern Hemisphere. The stratosphere has cooled, and there are now reliable indications that the troposphere has warmed. The height of the tropopause has increased. Individually, all of these changes are consistent with our scientific understanding of how the climate system should be responding to anthropogenic forcing. Collectively, this behavior is inconsistent with the changes that we would expect to occur due to natural variability alone.”