Atmosphere

The sunlight that penetrates the earth‘s surface is divided into:

• direct (insolation)
• diffused – here, aerosols play an important role, distributing and reducing solar radiation
• global – represents the sum of direct and diffused radiation
• reflected (albedo) – the proportion of reflected solar radiation from the earth surface

Part of the energy returns to the atmosphere as long-wave radiation (infrared) that warms the atmosphere. Part serves to evaporate the water, either in the soil or in the leaves of the plants, thereby bringing the water back into the atmosphere. Since the evaporation of soil moisture requires energy, soil moisture has a strong influence on the surface temperature. The texture of the soil surface (its roughness) affects the atmosphere dynamically through the action of the wind. The character of the soil is determined by both topography and vegetation. The wind also carries dust from the Earth‘s surface into the atmosphere (natural aerosols) that interacts with atmospheric radiation.

When the thermal radiation hits the object surface, part of the energy is absorbed by the object, part of the energy is reflected and the part passes through. The absorbed light is converted into thermal energy. The ability to absorb the amount of light depends on the color – the darker the object, the more light it absorbs and vice versa, the lighter it is, the less light it absorbs. Therefore, during a sunny summer day, we will be warmer in black than in white. Likewise, other black objects are hot in the sun. This is because black color absorbs infrared radiation and white reflects it.

Transform energy

Energy is transformed between the Earth‘s surface and the atmosphere by conduction, convention, and radiation:

• Conduction is the process by which energy transfer takes place between contacting particles with different temperatures. Air and water are relatively weak conductors. It occurs in solid bodies, in liquids, but also in gases. Most energy is transmitted through the earth‘s surface. At night, the Earth‘s surface cools and dissipates heat from the air. During the day, solar radiation warms the Earth‘s surface, which again affects the air temperature.
  
  
• Convection transfers heat by moving a group of molecules from place to place in the substance. It occurs in substances such as e.g. water and air whose molecules move freely. In the atmosphere it includes rising and falling air masses and smaller air parcels. These vertical movements effectively distribute heat and moisture throughout the atmospheric column and contribute to cloud and storm development
  
  
• Radiation is the transfer of energy without the involvement of a material substance in the transmission. Radiation can transmit heat through vacuum. Most of the solar energy is concentrated in the visible and almost visible parts of the spectrum. Shorter than visible wavelengths represent a small percentage of the total, but are extremely important because they have much higher energy. We‘re talking about ultraviolet radiation. The shorter the wavelength, the higher the energy associated with it.

Radiation, Convection, and Conduction