why surface temperature normal while at few kms height below zero?

Answer 1

There are different layers in the atmosphere with different temperatures. The lowest layer is the troposphere which is heated by contact with the ground. The ground absorbs the solar radiation and warms up. This warms the air above it by conduction and then convection helps to spread the warmth higher. Even so, the warmest temperatures are close to the ground while the coldest are at the tropopause, the boundary between the troposphere and the stratosphere.

In the stratosphere, temperatures rise to the stratopause and then fall through the mesosphere and then rise again in the thermosphere. The warm air in the mesosphere and stratosphere is caused by the absorption of UV radiation from the sun by the creation and destruction of ozone. The height of this activity is at the stratopause where temperatures similar to those on the surface are experienced.

Answer 2

What is normal? A few km above the ground the atmosphere is significantly thinner. Only reason we have a nice and cozy temperature down here is because of the atmospheres ability to trap heat. Without an atmosphere the average temperature would be -18 degrees centigrade.

Answer 3

What surface are we talking about? And by height do you actually mean depth.

If you're asking why the water temperature is lower below the surface is:
Colder water has a higher density than warm(er) water,(unlike many other chemical elements) so like in a pond colder water sinks and warmer water is found at the surface.

Answer 4

On the earth's surface, there are many objects (trees, concrete, etc.) that absorb heat and radiate that heat. Way up in the sky, the sun's rays just pass through without being absorbed. In addition, the air is much thinner which decreases the ability to transmit heat.

Answer 5

At 30.000 to 35,000 feet, the temperature has been measured at -60 degrees F,