In an outdoor experiment, I observed variations in surface temperatures of different materials while all of them were exposed to same ambient conditions (solar irradiation, wind speed etc). Please explain with some links to published work.
That depends upon the specific heat of the material. Higher the specific heat, more of the heat is retained (or given out) over a longer period of time, lesser the specific heat, lesser time it takes to give out heat (or imbibe), other conditions remaining same. For e.g. water having a specific heat of 1 takes more time to get heated as compared to any material say Copper (sp.heat 0.385), when the same heat is provided to them, separately.
It is also connected to the albedo of different surfaces - that means their reflection coefficient. It describes how much of the solar radiation is reflected on a surface. The not reflected part of that radiation is absorbed and transformed into radiation with a longer wavelength (visible spectrum -> infrared/heat). That is why darker surfaces (low albedo) absorb more energy and heat up more than brighter or shiny surfaces (high albedo).
As an example, surface roughness can effect heating rates of even the same material from light sources:
http://wrap.warwick.ac.uk/66632/
That is why we feel metals to be hot or colder than Wood or other non metals at same environment. The reasons are well explained above!!!
Both the effects of surface roughness, as the type of material that is exposed to atmospheric conditions, determine the characteristics of the boundary layer that forms on the interface, which locally modifies the pellicular coefficient in convective effects, too.
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