Tag: black body

The proper way to estimate climate change by observing how the earth as a black body responds to impulses.

The Earth can be described as a black body with energy coming in, mostly from the sun and an equivalent amount of energy being emitted. This follows the the Stefan–Boltzmann law, which states that the total energy radiated per unit surface area of a black body across all wavelengths per unit time j ⋆ j^{\star} (also known as the black-body radiant emittance) is directly proportional to the fourth power of the black body’s thermodynamic temperature T: j^{\star} = \sigma T^{4}. The average temperature on earth is 14 C or 287.15 degree Kelvin. This means that for every degree the earth gets warmer it emits 1.4% more energy. The sun’s incoming energy is nearly constant, well within +- 0,5%, so if the earth warms up more than one degree Celsius, it must come from changes on earth.

The best way to find out how the earth reacts to changes is to provide an impulse and see what happens. One such impulse was the open air atomic tests in the early 1960s.

Cosmic radiation in the form of iron nuclei is the major source of the generation of Carbon 14. When fossil fuel is burned there is very little C14 in the CO2 generated, but if it is burned by digestion of food, by fermentation, by burning wood or by wildfire, it contains the same concentration of C14 as was in the air at the time of the generation of the biomass. Since C14 has a half life of  5700 +- 40 years, we could find out the age of that biomass -or could we?

This is one of my very favorite slides. The best way of finding out how a black body responds is by introducing an impulse and see what happens. In this case the impulse was open air nuclear bomb tests, performed mostly by United States and the Soviet Union, but all occurred in the Northern Hemisphere. Test stations to see the amount of C14 in the air were set up in Austria and New Zealand. What did we learn? We learnt that the air mixes between the Northern and the Southern Hemisphere in about 2 years, and because the half-life of C14 shown here is 12.5 years, not 5700 years, it shows the absorption rate in the oceans and into new biomass. These values would have been difficult if not impossible to find out without open air Nuclear tests, Were the tests bad? You bet, but since they happened, you glean what you can from it. What else did we learn? You can no longer use carbon dating if there is any chance of contamination with newer biomass, or if it is newer than 1955 A.D.

In examining a black body, in this case the Earth for distinguishing properties it is very useful to observe how it reacts to impulses. We want to see which impulse response lead to climate change and which are just weather changes. All impulses lead to a response with a time delay.

There are those that say that climate change the worst threat to the world as we know it, worse than all out nuclear war. This is false.

Before we tackle the impulse change that everybody are worried about, the onset and growth of the industrial age and its outputs, let us examine few other impulses first.

The steady state of the earth is an ice age, and in the next segment we will examine how the earth ended the Ice age.

COVID-19 response, shut down all nonessential functions for 15days. What is the “black body” reaction of America?

When engineers and scientists want to study an object, the first step is often to study it as a “black body”, apply an impulse to it and study how the body reacts. One such “opportunity” is just now happening, the Coronavirus COVID-19 and how we, as a people react to it.

The flu season started innocently enough, but there was an increase in the number of healthcare visits for flue like symptoms, already when the flu season started in week 39 (October). At this time nobody had even heard of COVID-19 

The healthcare workers expected a higher flu season than average, but nobody expected this. On Dec 31 the Chinese government officially acknowledged that this virus could spread from human to human, but was still insisting it was largely contained to the live animal market in Wuhan. But Wuhan is a large regional hub, with lots of people, even international visitors were coming and going. No tests had been developed yet for the Coronavirus, so who is to say when the outbreak started. Certainly not the Chinese, they had successfully silenced a whistleblower, and he later died of the disease. We may never know the onset, and how many had spread the virus internationally before December 31. The silence of the Chinese government was a medical malpractice of worldwide importance. After Christmas the flu symptoms seem to have abated, but after President Trump issued the travel ban for foreigners who have recently been in China, people got nervous and the healthcare visits took off again. The question is, how much did the increased healthcare visits help or hurt? This chart shows the pneumonia cases, since this is usually how people die, not from the flu but from the following pneumonia.

Yes, there seems to be a negative correlation between health care visits and pneumonia deaths. More early attention to flu like symptoms and early intervention leads to fewer pneumonia deaths. Not really surprising, but earlier intervention seems even more important than I thought.

But what was really stunning is the effect the intervention to “flatten the curve”,  that is to slow the spread of the virus by 6 feet of separation “better six feet apart than six feet under“, telling everybody in the country to stay home if they do not have an absolutely essential job, don’t cough into open air, wash your hands with soap and don’t touch your face, had. Enough people seem to have obeyed. Did it make a difference? Check out the total deaths per week:

The number of deaths in the whole country shrank by twenty thousand per Week! This is remarkable. Will it continue, will changing hygiene and social separation continue, or will we return back to where we were before?

Time will tell, but there is much hope.

The reverse is just as good: