Tuesday 22 July 2014

DOES LUNAR SURFACE COOLING RATE REFUTE THEORY OF GREENHOUSE EFFECT?


The temperature at night time on the earth does not fall as rapidly as it would otherwise do if there was no greenhouse effect.The surface of the moon cools rapidly at night fall.

Tuesday 12 07 2014 Alberto Miatello describes in simple terms why he believes that lunar surface cooling rate refutes the theory of the greenhouse effect (GHE). This was published in Principia Scientific where you can read this article. It seems that a few simple yet astonishingly serious errors have been made here playing with data.


Here are two of his main arguments:-

Point 1:-
 “The highest temperature ever recorded (in the Death Valley, California, USA) was just 56°- 57°C, a meager highpoint when compared to the Moon’s equator where the temperature normally reaches 117°C (390K) . That is more than double the value, although – as we know – the quantity of solar irradiance is the same: 1367 W/m² in both places.”

Point2:-
“we have observed that on the Moon it takes 14.75 terrestrial days = 354 hours (!), at the lunar equator, to “cool off” from the highest temperature (117°C = 390K) to reach the lowest i.e.
 -173°C = 100K”

Somehow the writer implies that this information somehow refutes the greenhouse theory as stated in the title. However in support of his claim he focuses on criticizing a comment that apparently appeared in a “skeptical science blog” which he quotes as saying
“when the sun ‘goes down’ on the moon, the temperature drops almost immediately, and plunges in several hours down to minus 110 degrees C (-166F).”

He doesn’t succeed in disproving this either.

Let us look at both of the points above.

It takes 14.75 terrestrial days to cool from maximum temperature?

Really? The moon has the same face towards the Earth as it rotates. This means that a night or day on the moon is 14.75 terrestrial days.

http://www.universetoday.com/20524/how-long-is-a-day-on-the-moon/

How long would it take for a substance to cool from its maximum value to its minimum value? Exactly the time it takes to cool from its maximum value to its minimum value and assuming the moon’s surface heats and cools approximately symmetrically this will be half a moon day.
Has the second point actually said anything? Not really. This second point says nothing about the initial rate of cooling after the sun “goes down” which is more than likely similar to that quoted by the skeptical science blog. This would be greater than the extremely slow rate towards the end of the cooling period.
The writer then works out a meaningless average rate of cooling which to no surprise ends up less than the average rate of cooling on Earth..simply because the Earth has shorter days.
It should now come as no surprise that it takes 14.75 terrestrial days for the surface of the moon to warm from its minimum to its maximum temperature.

How fast does the surface of the moon cool?
In fact most of the cooling takes place not in 14.75 days but in the time the moon is eclipsed by the Earth. In that time the surface of the moon cools by 190C!
It looks like the skeptical science blog was quite accurate but Miatello has gotten this badly wrong as he works out a meaningless average rate.


 The temperature doubles!:-
The doubling is that on the centigrade scale not the Kelvin scale. If the temperature difference was 0.1C to 1 C, would that represent a 10 fold difference? The temperature in Death Valley is 330K.
330K to 390K is not double. Notice Miatello omits the 330K but not the 390K !

A planet with an ocean and an atmosphere.

The Earth of course transports heat, reducing the magnitudes of both maximums and minimums, and this is perfectly consistent with a GHE theory that can increase the average air temperature.

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