In an ideal condition with no wind, the absence of temperature difference between day and night would primarily be influenced by two factors: radiation and heat transfer.
During the day, the Earth receives energy from the Sun in the form of solar radiation. This incoming radiation warms up the Earth's surface, including the land, water bodies, and vegetation. As a result, the surface temperature increases throughout the day.
At night, when the Sun is no longer directly heating the Earth's surface, the surface starts to lose heat through a process called radiative cooling. The Earth's surface emits long-wave radiation (infrared radiation) into space. If there were no factors affecting the radiative cooling process, the surface temperature would drop significantly during the night.
However, in an ideal condition with no wind, the presence of a stable, calm atmosphere can significantly limit the temperature difference between day and night. Here's how:
Radiation Balance: In the absence of wind, the air near the Earth's surface tends to become still. This calm air acts as an insulating layer, reducing the rate of heat exchange between the surface and the atmosphere. As a result, the accumulated heat from daytime solar radiation is retained near the surface, preventing rapid cooling during the night.
Heat Transfer: Wind or air movement is an efficient means of heat transfer. It helps in mixing and redistributing heat in the atmosphere, evening out temperature differences. When there is no wind, the absence of convective heat transfer reduces the ability of the atmosphere to transport heat away from the surface, contributing to a smaller temperature difference between day and night.
It's important to note that even in ideal conditions without wind, some factors can still cause temperature differences between day and night. These factors include variations in solar radiation intensity, thermal properties of different surfaces (e.g., land versus water), geographical features, and local climate patterns. However, compared to situations with wind, the absence of wind generally leads to smaller temperature fluctuations between day and night.