Planet Earth: Deserts (70 Degrees?)

[The_wand_mirror]

So i've watched planet earth's chapter on deserts lately.

They said that the highest tempratures could get up to 70 degrees in the most extreme. So yeah, i was pretty skeptical about that (They could not possibly mean 70 Fahrenheit because that is only 21 Celcius)

I searched for the hottest places on earth, and also in the documentary itself it says that death valley is one of the hottest reaching something around 56 Celcius.

One article i found suggest that "the surface upon which the creatures live (lizards) can get as hot as 70 degrees celcius". So that would just mean the heat of let's say 50 degrees heats up the sand to 70 degrees?

Can anyone shed light on this for me, internet is not helping at all =p

 

[shamanyouranus]

What I assume you're asking is how a temperature of 50 degrees C can heat up the ground to 70 degrees C? (Not sure what the part with the 70 degrees Fahrenheit was about, cause that's cold in a lot of places).
To answer your question, sand retains heat a lot more efficiently than air does. Because of this the sand can store more energy from the sun than the air can, allowing it to get hotter. If you've ever been to a beach on a hot day, you'll know this to be true. If not, think of it like asphalt, which is always much hotter than the air around it (because it is black it absorbs more of the suns energy) or a poptart (which becomes like magma, even though the air in the toaster isn't nearly that hot.

 

[Boris_Spider]

Deserts are defined by receiving an average annual precipitation of less than 250 millimetres (10 in) per year, not by their temperatures. Antartica is classified as desert.

The documentary may of covered that, but some don't.

//\\oo//\\

 

[Nuclear]

I don't find that so amazing, it can be like -89C cold.

 

[Vunjo]

Well my father was in Egypt for some time, when it was max 50 Celsious in the air. So, like shaman said, the sand it probably much much warmer.

 

[The_wand_mirror]

Yeah the sand should always be warmer than the air but they didn't say this specificaly in the documentary. They just said the tempratures could rise to 70 degrees, but i can't find anything else confirming the sahara reaching 70 degrees anywhere else but in the planet earth documentary.