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THIS POST IS A STUDY OF THE ATTRIBUTION OF OBSERVED LUNAR WARMING TO HUMAN ACTIVITY AND OF ITS IMPLICATIONS FOR FEAR OF HUMAN ACTIVITY AND THE INTERPRETATION OF THE THE THEORY OF ANTHROPOGENIC GLOBAL WARMING IN THOSE TERMS. WITH THANKS TO ZOE PHIN AT  PHZOE.COM [LINK] 

PART-1: WHAT THE SOURCE DOCUMENT SAYS 

The various articles in the popular press and on the internet on the subject of anthropogenic lunar warming cite the same research paper but with somewhat different interpretations. The source document is the research paper by Nagihara etal published in 2018. The citation, abstract, and link to the full text of the paper appear below. It says that the when inserting the temperature sensors into the moon, the astronauts had caused darker underlying regolith up to the surface. (The word regolith implies mostly loose rocks and pebbles and not the kind of soil we have on earth.) The darker material that was brought to the surface then absorbed more solar energy and made that spot warmer meaning that this was a localized warming and not a warming of the whole of the moon. A possible flaw in this conclusion is that the dark matter would be lightened by sunshine and the intense heat of insolation when the sun shines. The other complication in tracking and identifying localized moon warming is that the the localized spot in question goes through an intense 56-day temperature cycle from +100C when the sun shines to -173C when it is dark. The bigger confusion in this issue is the way the findings were reported in the popular press with some interpreting the localized warming as a warming of the whole of the lunar surface. A third complication, pointed out by Zoe Phin, is that the role of significant heat sources in the moon’s core and mantle have not been considered in the interpretation of long term changes in surface and subsurface temperature.

Nagihara, S., et al. “Examination of the Long‐Term Subsurface Warming Observed at the Apollo 15 and 17 Sites Utilizing the Newly Restored Heat Flow Experiment Data From 1975 to 1977.” Journal of Geophysical Research: Planets 123.5 (2018): 1125-1139.  ABSTRACT:  The Apollo heat flow experiment (HFE) was conducted at landing sites 15 and 17. On Apollo 15, surface and subsurface temperatures were monitored from July 1971 to January 1977. On Apollo 17, monitoring took place from December 1972 to September 1977. The investigators involved in the HFE examined and archived only data from the time of deployment to December 1974. The present authors recovered and restored major portions of the previously unarchived HFE data from January 1975 through September 1977. The HFE investigators noted that temperature of the regolith well below the reach of insolation cycles (~1 m) rose gradually through December 1974 at both sites. The restored data showed that the subsurface warming continued until the end of observations in 1977. Simultaneously, the thermal gradient decreased, because the warming was more pronounced at shallower depths. The present study has examined potential causes for the warming. Recently acquired images of the Lunar Reconnaissance Orbiter Camera over the two landing sites show that the regolith on the paths of the astronauts turned darker, lowering the albedo. We suggest that, as a result of the astronauts’ activities, solar heat intake by the regolith increased slightly on average, and that resulted in the observed warming. Simple analytical heat conduction models with constant regolith thermal properties can show that an abrupt increase in surface temperature of 1.6 to 3.5 K at the time of probe deployment best duplicates the magnitude and the timing of the observed subsurface warmings at both Apollo sites. [FULL TEXT] .

PART-2: WHAT THE THE POPULAR PRESS SAYS

(1) THE SPACE.COM ARTICLE JUNE 14, 2018. AN EXAMPLE OF A FAIRLY ACCURATE REPORT OF THE NAGIHARA FINDINGS: “Astronauts caused the mysterious warming detected by the Apollo moon missions in the 1970s, a new study suggests. When astronauts walked or drove their moon rover near buried heat-flow probes, the activity disturbed and displaced surface soil, exposing the darker dirt below. This newly unearthed material absorbed more sunlight, causing the soil to heat up, according to the study. The new results not only help solve a decades-old mystery but also provide a lesson for the architects of future missions to Earth’s nearest neighbors, study team members said. In the process of installing the instruments, you may actually end up disturbing the surface thermal environment of the place where you want to make some measurements. That kind of consideration certainly goes into the designing of the next generation of instruments that will be someday deployed on the moon. Astronauts deployed the heat-flow probes during the Apollo 15 and Apollo 17 missions, in 1971 and 1972. The goal was to determine how much heat moves from the lunar interior to the surface, which in turn would yield insights about the moon’s structure and composition. The probes operated through 1977, beaming data home to NASA. Apollo 17 was the last crewed lunar mission; nobody has set foot on the moon since then. JSC preserved these data on magnetic tapes, some of which which were later archived. The rest have apparently been lost. The measurements made through 1974 showed a slight uptick in temperatures in the lunar near-surface over the previous few years. This trend puzzled researchers at the time. In their research, Nagihara etal unearthed hundreds of weekly logs that recorded heat-probe observations that extended the data record several additional years and showed subsurface warming at the heat-probe sites with the temperature rise greater closer to the surface suggesting that the warming started at the surface and worked its way down. The warming was a localized phenomenon. Astronaut activity had darkened the soil in these areas, which absorbed more solar energy and warmed the soil. The surface temperature rise  was 1.6C to 3.5C . Source(Journal of Geophysical Research: Planets, April 25 2018).

(2)  THE LIVESCIENCE ARTICLE, JUNE 13, 2018: AN EXAMPLE OF AN ALARMISM REPORT IN WHICH THE LOCALIZED SURFACE WARMING REPORTED BY NAGIHARA, IS REPORTED AS A WARMING OF THE ENTIRE LUNAR SURFACE:  Lost’ NASA Tapes Show Humans Sort of Caused Global Warming on the Moon Too. June 13, 2018: Apollo astronauts may be responsible for the moon’s mysterious temperature spike in the ’70s, a new study suggests. There is a decades-old mystery at NASA: Why did the moon’s temperature suddenly rise 2C right after the first astronauts planted their flags there? When scientists first encountered this puzzle in the early 1970s, they knew that lunar regolith could give astronauts a fever; was it possible that astronauts were giving the moon a fever right back? Seiichi Nagihara, a planetary scientist at Texas Tech University, suspected that the key to explaining this mysterious lunar heat wave lurked in temperature readings recorded by Apollo astronauts between 1971 and 1977. The only problem was that hundreds of the reels of magnetic tape holding those records went missing nearly 40 years ago, thanks to an archival blunder. Now, after a grueling eight-year search, Nagihara and his colleagues have tracked down and restored more than 400 reels of those lost NASA tapes. In a new study published April 25 in the Journal of Geophysical Research: Planets, the researchers used these tapes to propose a logical hypothesis to explain the temperature increase: The astronauts, later nicknamed the “dusty dozen,” may have been way too dusty for their own good. You can actually see the astronauts’ tracks, where they walked and we can see where they scuffed dirt up  and what it leaves behind is a darker path. The 12 Apollo astronauts who walked on the moon between 1969 and 1972 kicked aside so much dust that they revealed huge regions of darker, more heat-absorbing soil that may not have seen the light of day in billions of years. Over just six years, this newly exposed soil absorbed enough solar radiation to raise the temperature of the entire moon’s surface by 2C. In other words, the astronauts walking on the moon changed the structure of the regolith. The dark patches of soil uncovered by the Apollo astronauts are clearly visible in overhead photographs. Astronauts first planted temperature probes on the moon’s surface during the Apollo 15 and 17 missions, in 1971 and 1972. While these probes transmitted data back to the NASA ,only the first three years of recordings were ever archived. For their new study, Nagihara etal found 440 of  the missing tapes.  The logs included temperature readings taken from the Apollo probes between 1973 and 1977, meaning the researchers could fill in some of the gaps left by the other missing tapes. Climate change on the moon. The researchers discovered that probes planted near the moon’s surface recorded a greater and faster temperature jump than the probes planted deeper down found. This indicated that the temperature spike was beginning at the surface and not within the moon itself. Photos showed that areas near the Apollo landing sites were crisscrossed with dark streaks where the astronauts had walked or driven about the moon’s surface, apparently kicking a lot of ancient dust aside. In fact, the mere act of installing the temperature probes may have thrown off those probes’ measurements by altering the surface environment around the instruments — and significantly increasing the surface’s temperature.

PART 3: CRITICAL COMMENTARY

(1)  The researchers found that point locations where temperature probes were inserted had warmed and attributed the warming to the insertion of the probes arguing that the insertion must have brought up darker regolith from under and the darker material absorbed more sunshine. Without additional information or computations this evidence in itself does not prove causation. We know that these temperature probe locations had warmed but we don’t know the temperature of non-probe locations in the vicinity of the the probe locations to show that these temperatures are higher than they would have been without the probe. Also, no computation of the differential solar energy absorption by the two different regolith colors is available for a heat balance to determine whether the temperature differential is consistent with the heat balance. Therefore, the attribution of the warming to human activity in the form of inserting temperature probes is one of convenience and a creation of confirmation bias. 

(2)  Even if we accept that the temperature probe insertion had caused the warming, the generic extension of this cause and effect relationship to the impact of human activity is not possible. Human activity on the moon involved much more than inserting a few temperature probes. It involved for example, the landing of a space craft and exploration on foot by the astronauts. The interpretation of the insertion of temperature probes in a generic way as “human activity” appears to be derived from a yearning in research of our times to blame humans or to predict harmful effects of human activity.

(3)  And even if we accept the finding that temperature probe insertion causes the insertion point to warm, the further extension of that finding by the popular press into a warming of the entire surface of the moon should have been corrected by the authors. They did not do that and in fact one of the authors of the research paper was closely involved with the authors of the LiveScience paper but failed to correct their interpretation, apparently in cahoots with LiveScience in their rendering of the inconsequential findings in terms anthropogenic lunar warming.