Sometime, some things, just make you want to go “hmmmmmm”….
I was looking for any record of the lunar surface temperature. Figured if we could show it was warming / cooling in sync with the Earth, we could finger something other than CO2 as causal. If they did NOT warm together, then it would strength the case for something ‘special’ about the earth. If the moon was cooling while the earth warmed, well, something is warming and it’s not the sun…
So I find this paper. It has WAY too short a data series (as it is from a surface instrument left by Apollo 12 on the lunar surface and we have not gone back to do maintenance…) yet it still has something very interesting; even if not what I’d expected. The moon warms while the earth COOLS. What? Backwards from CO2?
This allowed him to uncover a lunar night-time warming trend from mid-1972 to late 1975, which was consistent with a global dimming of Earth that occurred over the same period and was due to a general decrease of sunlight over land surfaces. (Widespread ground-based radiation records from that period show that solar radiation reaching Earth’s surface during that period decreased significantly, for reasons that are not completely understood.)
OK, so we know it got cold in the ’70s (that whole ‘new ice age’ thing was popular then, and it snowed in my home town. Something only known from a half dozen or less times in history). WHY was it cooling? Some “global dimming” as the sunlight decreased.
What happened to the Earth energy budget, per the study? MORE heat signature was visible on the moon as more heat left the planet…
Gee, solar energy drops (sunspot proxy see below), Earth dumps MORE IR to space. Later sun brightens (as the ‘global dimming’ ended and we entered a new more active sunspot phase) and the Earth warms… Don’t suppose it might be due to LESS IR leaving? Driven by a solar process? (CO2 was rising nicely in the ’70s. I know as I was driving an old Chevy Impala that got about 10 mpg and Dad had a Dodge Charger that got about 7 mpg when you stepped on it. It got much better when cruising, but with a big old 440 4-barrel carb and hemi engine, who could EVER not step on it ;-)
OK, the actual paper is here:
It mostly just goes on about how important Global Warming is and how ideal the moon would be to measure it, slips in the ‘upside down’ heating as earth cools, and then laments the lack of more instrumentation there. Still, it has its moments. The temperature series looks to run from 1971 to just into 1976 January.
The accidentally obtained Apollo 15 lunar surface temperature time series reveal distinct characteristics in the lunar daytime and nighttime surface temperatures. Superimposed on the diurnal and seasonal variations was an inter-annual daytime cooling trend over the observation period. In contrast, there was an upward trend in the lunar nighttime temperature which supposedly is controlled by the radiation from Earth.
OK, daytime temps dropping as the sun goes a bit quiet. Got it…
More importantly, there is a warming trend in the nighttime temperature over the entire observation period. The fluctuation of the nighttime temperature did not follow the same pattern of the daytime temperature. The peaks and troughs are offset in the day-time and nighttime temperatures.
So the moon night side has consistent warming trend over the observation period, and that shows the Earth IR flux delta is inverse with surface temperature; but varies with solar changes. Quiet sun, more IR flux out.
The reproducible daytime temperature trends of the Apollo 15 time series provide an independent confirmation of a stable radiation incoming from the Sun. In contrast to the lunar daytime maximum temperature variation, there is an upward trend in the nighttime minimum temperature.
So, solar side is more or less stable, but with a slight cooling trend.
More intriguingly, the fluctuation in the lunar nighttime temperature does not have the same rhythm as the fluctuation in the daytime temperature. To a great extent, the night-time temperature variation is independent of daytime temperature. This is evidence that daytime and nighttime temperatures at the lunar surface are governed by two different radiation processes, namely the solar radiation and terrestrial radiation.
The observed lunar nighttime warming from mid 1972 to the end of 1975 appears to be consistent with the global dimming of Earth prior to the late 1980s (Stanhill and Cohen, 2001; Pinker et al., 2005; Wild et al., 2005). Global dimming is resulted from a general decrease of sunlight over land surfaces. Widespread ground-based radiation records show that the solar radiation reaching the Earth’s surface decreased by about 5% between 1960 and 1990 (Stanhill and Cohen, 2001). Given a constant total solar irradiance, the less sunlight reaches the Earth’s ground surface, the more solar radiation is reflected to the deep space, and the higher lunar nighttime temperature would be. To what an extent the observed nighttime lunar warming in the early 1970s can be explained by the reported global dimming on Earth remains yet to be investigated.
OK, so what caused the “Global Dimming” and why, just why, was it able to overrule the very great increase in CO2 post W.W.II and during the heyday of the US Automobile as Living Room?
Whatever it was, how does it modulate IR flows off planet such that as the planet cools, more leaves? Exactly the opposite of the radiation budget guys and their models…
Think maybe it had anything to do with clouds and the water cycle? Maybe that whole sunspot thing?
(from the sunspot wiki)
So gee, looks like we had a runt for a cycle in #20, right on top of 1970, then it drops down to a minimum at about 1975-1976. Just like now, TSI holds up pretty well. Even has added radiation down in the lower bands (so maybe why the moon continues to warm, better absorption of those bands closer to IR?), rather like now. Yet the Earth gets cold.
Houston, I think we have a ‘climate science’ problem…
The giant “Dig Here” on this one is pretty simple. Try to find a 1970s history of cloud cover. Try to find a history of UV and EUV. Maybe add in some cosmic ray counts. Connect all the dots.
Looks to me like we have a small ‘test case’ here, just waiting to be worked into a masters thesis… I don’t have time to pursue it all right now, but if folks know of appropriate sources, please put up some links. If Vukcevic can match this to his formula or if the gas giant planet orbital mapping can be shown to match too, all the better.
What we do have here, pretty clearly, is a direct comparison of a ‘black body’ like object and one with clouds and convection. A radiation model vs a convecting model. And the convecting model ran ‘backwards’ compared to the radiative one…
(Sidebar: This posting was composed entirely while running from a CD with no disk activity at all…)