September 2023 – Notes from Dad

Evan’s school has been fortunate enough to have excellent science teachers. Recently he was assigned a paper and asked to understand it, and then present the information to the class. The paper is at https://pubs.usgs.gov/fs/fs-0095-00/fs-0095-00.pdf and is titled “The Sun and Climate” and is five pages of closely formatted text with several graphs. The required 25-35 references follow on page 6. The article, unlike an article in a scientific journal, does not list any authors. So I will credit Walter E. Dean of the USGS whose name appears at the end as a contact for more information.

I didn’t set my eyes on a scientific paper till I was in graduate school. Yes – not even undergraduate college. We were given study materials, typically in textbooks, and if you mastered what was between those covers, you were golden. I am excited the this is what is expected of Evan at the beginning of 8th grade. So I took more interest in this than I normally would. Evan created his set of notes. It took him hours and hours. The text is written in a form that makes it harder to understand than what an 8th grader is used to (“The most prominent cycle in the Castile is a salinity cycle with an average period of about 2,500 years in which the cycle begins, in the extreme, as a laminated limestone with thin calcite and anhydrite laminae. The anhydrite laminae then become thicker, and the cycle ends, in the extreme, with anhydrite and halite varves.”). I asked Evan to email me his notes from the paper.

In seemingly unrelated news, yesterday Vivian sent me a text from school saying that her teacher asked her to download an app called DigiExam on to her personal laptop. She wanted to know if she could wait and come home and chat with me about it. A quick look at their website and reviews shows that DigiExam is a Swedish app that helps teachers and institutions administer exams with less or no supervision. Your laptop on which you take the exam is your proctor. It takes periodic snapshots of your screen. It turns on your laptop camera and records you (and anything else in it’s view). It analyses your eye movements to see if you perhaps have another source of content close by like another computer screen that you are consulting frequently. It does not allow other tabs to be opened in your browser and records what tabs you do try to open. Same with other apps on your computer desktop. The idea is for instance to discourage you from opening another tab to ChapGPT and copying and pasting your questions and the AI’s responses. Very good. Can it be turned on and off remotely, and who will be able to do that? Or even worse, is it on all the time? Here’s a question I expect at a future congressional hearing once DigiExam becomes required everywhere, from a concerned congressman: “If my daughter sits in her underwear and takes an English exam at home, is that camera recording her? Who has access to that recording and for how long? Is there a room full of low-paid remote nannies somewhere offshore sifting through videos of kids that the software flagged for one reason or another?”

Why did Vivian’s school take the draconian step of ask students to download and install surveillance software on their personal computers (which she didn’t)? The rise of AI is causing panic. While policy makers ask abstract but important questions (“is critical writing worth teaching any more?”, “is the college essay dead?”), the poor English teacher does still need to grade that pile of 11th grade homeworks comparing Whitman to Dickinson. If half the class used ChatGPT it wouldn’t be fair.

Back to Evan. I sat him down this morning and opened a tab to ChatGPT.

ME: You are a science journalist

AI: Certainly! I can act as a science journalist and provide you with information on various scientific topics or write articles on specific subjects of interest. Feel free to ask me any questions or provide a topic you’d like me to cover, and I’ll do my best to provide you with accurate and engaging information.

ME: Please read the following text and categorize it according to the school english grade level that it would be appropriate for. The text is:

[I copied and pasted the first two paragraphs of the USGS paper]

Many geologic records of climatic and environmental change based on various proxy variables exhibit distinct cyclicities that have been attributed to extraterrestrial forcing. The best known of these are the changes in Earth’s orbital geometry called Milankovitch Cycles, with periodicities of tens to hundreds of thousands of years. However, many cycles seem to have subMilankovitch periodicities, commonly on decadal and centennial scales, similar to those of known solar cycles. A direct connection between solar irradiance (solar constant) and weather and climate has been suggested for more than 100 years but generally rejected by most scientists, who assume that the effect of solar variations would be small. However, recent satellite radiometer measurements and modeling studies indicate that small changes in total solar irradiance could produce global temperature changes of the magnitude suggested for climatic events such as the Little Ice Age (A.D. 1550–1700). The best known and documented solar cycle is the 11-year sunspot cycle (Schwabe Cycle; fig. 1), during which the number of dark blotches (sunspots) on the sun’s surface increases from a minimum to a maximum then back to a minimum over a period of about 11 years. The origin of sunspots is not fully understood, but thanks to satellites such as the Solar and Heliospheric Observatory (SOHO), scientists are learning rapidly. What is known is that during the period from A.D. 1645 to 1715 very few sunspots were observed. This period is called the Maunder Minimum (fig. 1) after E.W. Maunder, superintendent of the Solar Department of the Greenwich Observatory in England, who continued the observations of the German astronomer, Gustav Spörer (Eddy, 1976). Spörer noted a dearth of sunspots during a 70-year period beginning about A.D. 1645, and during an earlier 90-year period beginning about A.D. 1460 (now called the Spörer Minimum). An early association between sunspots and terrestrial phenomena was the observation that the number and intensity of aurora borealis sightings were greatest during sunspot maxima when the sun was most active (active sun), and lowest during sunspot minima (quiet sun). Another terrestrial observation was that the Maunder Minimum coincided with the coldest part of the Little Ice Age.

AI: The text you provided contains a high level of scientific terminology and concepts related to geology, climatology, and solar phenomena. It would be most appropriate for students at the high school level or above, typically for students in grades 11 and 12 who have a strong interest in science or are studying advanced science courses. This text would also be suitable for college-level students studying geology, climatology, or astronomy.

The text discusses topics such as Milankovitch Cycles, solar irradiance, sunspot cycles, and their potential effects on climate. It assumes a certain level of prior knowledge in these fields, making it less accessible to younger students or those without a strong science background.

Evan smiled when he read this part. Then I asked the AI to produce the kinds of notes that Evan had be asked to.

ME: Read the following text and extract as brief bullet points the most important concepts discussed. Please do not add new information not contained in the text. The text is: [followed by the same first two paragraphs from the USGS paper]

AI: Important concepts discussed in the text:

Geologic records show cyclic climatic and environmental changes attributed to extraterrestrial forces.
Milankovitch Cycles are well-known Earth’s orbital geometry changes with long periodicities.
Some cycles exhibit shorter periodicities, resembling solar cycles.
There’s a historical debate about the connection between solar irradiance and weather/climate.
Recent measurements suggest small solar irradiance changes can impact global temperatures.
The 11-year sunspot cycle is the best-known solar cycle, with sunspots on the sun’s surface.
The Maunder Minimum was a period with very few sunspots from A.D. 1645 to 1715.
Sunspots were studied by scientists like Gustav Spörer and E.W. Maunder.
Aurora borealis sightings were linked to sunspot activity.
The Maunder Minimum coincided with the coldest part of the Little Ice Age.

As a comparison, here are the notes from Evan’s brain for the same first two paragraphs:

The orbital geometry changes over time and is called the Milankovitch cycles
- Periodicities of tens to hundreds of thousands of years
There are sub-Milankovitch cycles usually on the scale of centuries and decades
- Similar to known solar cycles
A direct connection between solar irradiance, climate, and weather has been suggested for more than 100 years but has been rejected by many scientists who assume the effects of solar variations would be small
Recent satellite radiometer measurements have indicated that small changes in the solar irradiance could cause changes on the scale of the Little Ice Age (A.D. 1550-1700)
Best known and documented solar cycle was the 11 year sunspot cycle (Schwab Cycle, fig.1)
- Number of sunspots increase from minimum to maximum to minimum again over an 11 year period
The origin of sunspots is not fully understood
- We are learning rapidly because of new solar satellites (such as SOHO)
During 1645-1715 the amount of sunspots was very low
- This period is called the Maunder period after E.W. Maunder
  - E.W. maunder carried on the observations of German astronomer, Gustav Spörer
Gustav Spörer noted a dearth of sunspots over a 70 year period beginning a about A.D. 1645 and a 90 year period from A.D. 1460
One of the first connections they noticed was that the number and intensity of aurora borealis were greatest during the sunspot maxima
The sunspot minima coincided with the coldest part of the Little Ice Age

I was duly impressed by both Chat GPT and Evan (I had watched Evan do a large part of this work so I knew he did it the hard way). I don’t think DigiExam is the answer, though that won’t stop many schools from jumping on that bandwagon. But if I were a teacher or a parent (one of which I am) I’d be pretty concerned about the effects of AI on our kids’ education (and their lives). By the way, here’s the rest of Evan’s notes about that paper:

Recent studies have shown that the production of radio production (carbon 14) is related to solar activities
- Radiocarbon is produced by the bombardment of nitrogen 14 in the atmosphere by neutrons from outer space, which are called cosmic rays
An increase in solar activity (more sunspots) is accompanied by an increase in the “solar wind,” which is an outflow of ionized particles, mostly protons and electrons, from the sun
Carbon 14 concentration in the atmosphere is lower during the sunspot maxima and higher during the sunspot minima
Carbon 14 concentration in the atmosphere is recorded in the tree
- A relationship between carbon 14 and age can be made
  - Expressed as 𝚫C¹⁴
    - Represents the radiocarbon levels compared to the levels in the 19th century
They have reconstructed the 𝚫C¹⁴ for the past 11,000 years using decedal and bi-decedal wood samples (fig. 2A)
- Shows that the C¹⁴ production was higher during the mid-holocene era (approx. 7,000 years ago)
- Then steadily decreased until approx. 1,000 years ago
When you remove the long term trend you can see that there are cycles with periods of about 2,000 years
- Called the Hallstadtzeit cycle (fig. 2B)
Looking at the last 1,000 years you can see that the C¹⁴ production was higher during the Maunder and Sporer minima
There were also peaks at A.D. 1300 and 1050 which have been named the Wolf and Oort minima
These cycles in C¹⁴ production last and, by relation solar activity, have periods of about 200 years
The sunspot minima precede the C¹⁴ maxima by about 20-60 years wich is how long it takes for the effect of solar activity on 14C production to cycle through the atmosphere-ocean system
When they perform a spectral analysis on the C¹⁴ cycle there are other peaks in addition to the 2,000 and 200 years (fig. 4)
- Some prominent ones are at 400 and 88 year intervals
  - 88 year is called the gleisberg cycle and is thought to be the result of amplitude modulation of the Schwabe cycle
A 22 year periodicity called the “double sunspot” or Hale cycle may also be because of amplitude modulation of the Schwabe cycle
Satellite radiometry over the last 20 years has shown the the total solar irradiance varies 0.1 percent during the 11-year cycle
A change in total solar irradiance over one 11-year corresponds to about a 0.5 – 1.0 C change in the global tropospheric temperature
Total irradiance is highest during the sunspot maxima and lowest during the sunspot minima
- May seem counterintuitive because the sunspots would make the sun dimmer but the bright area surrounding a sunspot (faculae) cause the sun to brighten at peak activity
It is estimated that during the Maunder Minimum, total solar irradiance was reduced by 0.2 percent relative to a present quiet sun but total UV radiation was reduced by 1.04 percent
- Important because UV radiation modulates the ozone production
  - Ozone production regulates the middle and upper atmosphere
Crowly and Kim estimate that a total warming of 0.8-0.9ºC occurred between the minimum of sunspot activity during the Maunder Minimum and the maximum sunspot activity during the mid-20th century
According to Lean and others the surface temperature of the earth has increased 0.55 C since 1860
- About half of this could be due to the solar warming since the Maunder minimum
  - However 0.36 of the 0.55 has happened since 1970 and only 0.11 of that can be accounted for by solar forcing
  - The rest could be due to greenhouse warming or some other cause
The period of low 14C production between about A.D. 1100 and 1250 is called the Medieval Maximum of sunspot activity (fig. 3)
- Coincides in time with a warm interval called the Medieval Warm Period
The general solar activity was low during the period of 1300-1900
- Two distinct lows, the Sporer and Maunder minima
- Only in the 20th century has the solar activity increased to the levels of during the medieval maximum
There has been an observed connection between solar activity, geomagnetic storms, and the climate
strong solar-geomagnetic disturbances in the troposphere during winter were often followed within a few days by a deepening of subpolar low-pressure systems over the North Pacific
A weaker magnetic field lets more cosmic easy in which results in more C¹⁴
The cosmic ray reflux also affects cloud microphysical processes
Dust records show centennial-scale variations of increased dustiness during periods of reduced solar activity
Cycles of 200 years in the dust records match with the Suess cycles in radiocarbon
The mid-Holocene may have been a time of increased eolian activity for much of North America (particularly in the Great Plains)
A varve-calibrated eolian dust record for the last 1,500 years in Elk Lake shows distinct cycles with dominant periodicities of 400 and 84 years (fig. 6)
The Elk lake record is one of many that show cycles that match up with solar cycles
The dust record in the GISP2 ice core exhibit shows distinct cycles of 11, 22, 90, and 200 years, believed to be associated with the Schwabe, Hale, Gleissberg, and Suess solar cycles, respectively
Suess solar cycles, respectively (Ram and others, 1997; Ram and Stolz, 1999). The physical connection between solar activity and dust is postulated to be variations in precipitation patterns in the Greenland dust-source areas caused by changes in cloud cover and cloud microphysics, which in turn are affected by the cosmic-ray flux
The varve thickness record shows cycles with an average period of about 20 years superimposed on longer cycles with an average period of about 200 years. Could these be related to “double sunspot ” (Hale) cycles and “Suess wiggles”? In fact, could the dominant 2,500-year cycle in the Castile Formation be related to the dominant 2,000-year cycle in the 14C spectrum (Hallstadtzeit Cycle
A modern example is titanium concentration in sediment samples from the gulf of california
- Have a striking cycle over the last 200 years with about 10 year periods
- The average titanium concentration in the record illustrated for core BC6 in figure 10 (0.35 percent) is more than twice the average titanium concentration (0.16 percent) in sediments deposited over the same time interval recovered in core BC50 (fig. 9)
- These cycles match up with the 10-12 year cycles of precipitation observed in tree rings
Could variations in rainfall and river flow on the west slope of the Sierra Madre somehow be connected with the solar sunspot cycle as are changes in precipitation postulated for dust sources in Greenland ice cores?
It can be said that if you look hard enough anything can relate to the solar cycles
- The challenge to geologists and atmospheric scientists is to test these correlations with reasonable models of how solar cycles could affect the atmosphere and geologic processes at the surface of the Earth.

Month: September 2023

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