December 14, 2020

Weather signs at sea – humidity

The amount of water vapour in the air varies from place to place and from time to time, and is an important factor in determining the nature of the weather. The amount of water vapour that the air can hold in an invisible state is limited and varies with the […]
December 14, 2020

Cloud formation

Clouds are formed when warm, moist air rises until it reaches the air’s saturation point (dew point). After this the moisture in the air condenses into visible droplets and clouds are formed. There are two basic types of cloud. Cumulus clouds. When air is heated by the surface of the […]
December 14, 2020

Fog and mist

December 14, 2020

Rain, snow and hail

If the cooling process which gives rise to cloud formation is continued, the droplets of which the cloud consists grow in size until they become too heavy to remain suspended in the air and they fall to the ground as rain. The longer the droplets are held aloft by the […]
December 14, 2020

Wind

Vertical and horizontal movement. Wind can be defined as the movement of air from a high pressure to a low pressure area. Consider two columns of air AB and CD. They are of equal cross sectional area, height and temperature and the pressure at A and C are equal and […]