Climate modeling, the E-6B, Hidden Figures, and Teraflops

Math, yuk! But making science discoveries, thus making sense of nature, is wed to our ability to describe what we observe in mathematical equations. In 1896, the Godfather of climate science Svante Arrhenius, gave us our first global warming equation. It took him a whole year of meticulous math equating.

Computers now reign supreme, but this is a recent phenomenon.  The movie “Hidden Figures” is based on the fact that our mercury astronauts depended on female human computers for the successful completion of their flights. This was while, in 1961, electronic computers were literally making human computers obsolete.  Science, flying, and the fairer sex…. what more could one want in a great movie?

Now, I am going to digress to criticism of “Hidden Figures”.  In my time, in fact in 1961, math computations depended on the slide rule. Hollywood probably could not find enough slide rules today to use them in Hidden Figures, and the producers probably would not have recognized them anyway. But, I guarantee you, we went to the moon on the backs of men and women who knew how to use a slide rule.

When I entered the USAF Academy in 1969 I was introduced to a buzz haircut, twenty push-ups just for existing, more that a few derisive terms, one mile runs in combat boots with an M1 rifle, plus a slide rule. Given that introduction, I thought the slide rule was a simply another instrument of terror and banished it to my closet. Later, talented, patient instructors taught me how to use it.

In flight school, we were introduced to the E-6B. This is a circular slide rule that, if you are good with it, you can figure out any mathematical equation known in aeronautics…with one hand!  It is still used and goes by the name “whiz wheel”. When running low on fuel while drilling into a headwind it is also called a, “prayer wheel”.

I think it is important to note that Spock, in the Star Trek episode “The Naked Time”, uses an E-6B to compute the time of impact as the Enterprise was on course to auger into a planet.

Ok, back to climate science.  We know we are rapidly warming the climate simply because our meteorologists, world-wide, have been taking temperature measurements for a long time. That is “global warming”.  Trying to predict the weather we can expect in the future, is “Climate Change” and is much more complicated.  But, thanks to the computer revolution, the scientists are on it.

Briefly, our weather is caused by the uneven heating of the earth. The equator, especially the equatorial oceans absorb the bulk of the sun’s energy.  This heat is moved towards the poles by ocean currents, air currents, and dynamic weather circulation patterns with names like the, “Hadley Cell”.  Weather systems are spun around by the Coriolis effect caused by the rotation of the earth. Land masses, especially mountains, throw up barriers. It is complicated. At the National Climate and Atmospheric Research labs, scientists are continually working to fine tune their understanding of all these factors. Here is a chronological listing showing the progression of their scientific understanding. Year by year they add the mathematical impact of each factor into their climate models:

1960s - Simply the atmosphere as then known.

1970s + Ocean currents and Major Land forms (topography).

1980s +Sea Ice and Snow (Loss of reflectivity of sunlight or albedo due to melting).

1990s +Sulfate Aerosols (both Human Pollution and Volcanic Eruptions) plus

                Ocean Currents, and Land Vegetation.

2000s +Carbon Aerosols, Dust, the Nitrogen Cycle, Sea Spray, Precipitation, Land use, Ice Sheets, plus

             Marine Life.

These factors are entered into grids on a map. The factors above are rendered down to mathematical equations that change with the seasons. The smaller the grid, the more precise the computer results.  But, each step up in detail requires a mega-leap in computing ability. It was not long ago that 10-mile square grids were normal. Today NCAR uses 1.5-mile squares grids. (4km).

To ensure accuracy, scientists “back-cast”. Back-casting is simply taking the data they have from the past and loading it into the computer. Then, they turn on the computer and watch to see if, when it reaches the present, it mirrors present day climate. If it does, the model and computer are accurate.

The effort to use all contributing factors in a precise way takes a powerful computer. The term “FLOPS” which is short for, “floating point operation per second” is used to measure computational power. The higher the FLOPS the stronger and faster the computer.  To give you an idea of how fast computers work today a handheld calculator is functional at 10 FLOPS.  Our climate computers work in the category of “TERAFLOPS” or 10,000,000,000,000 computations per second. That is ten thousand-million computations per second!

What does this mean to me?

First, if Svante had one of these computers in 1896, he could have turned it on when he got out of bed and he would have had his equation before he finished his first cup of coffee.

Second, it means brilliant scientists work with observational tools, computers, and laboratories that I will never be able to fully understand.  But, I and Spock can read abstracts of studies written in English. Both Spock and I, with or without our trusty E-6Bs, know that there is a climate impact point for planet earth and we, you and I, need to show a little enterprise if we are to safely navigate our way to safety.