But have you ever wondered why?? Basically, air cools as it rises, which can cause water vapor in the air to condense into liquid water droplets, sometimes forming clouds and precipitation. On the other hand, sinking air is associated with warming and drying conditions. So what does this have to do with high and low pressure? As it rises and cools, water vapour condenses to form clouds and perhaps precipitation.
This is why the weather in a depression is often unsettled, there are usually weather fronts associated with depressions. High and low pressure. What do we mean by 'pressure'? Weather chart On a weather chart, lines joining places with equal sea-level pressures are called isobars. What is relative humidity?
Relative humidity is the ratio of water vapor contained in the air compared to the maximum amount of moisture that the air can hold at that specific temperature and pressure. Humans are very sensitive to humidity, as the skin relies on the air to get rid of moisture. The process of sweating is your body's attempt to keep cool and maintain its current temperature.
If the air is at percent relative humidity, sweat will not evaporate into the air. As a result, we feel much hotter than the actual temperature when the relative humidity is high. What is an air mass? An air mass is an extremely large body of air whose properties of temperature and moisture content humidity , at any given altitude, are fairly similar in any horizontal direction. Air masses can cover large hundreds of miles areas.
Air masses can control the weather for a relatively long time period: from a period of days, to months. Most weather occurs along the periphery of these air masses at boundaries called fronts. Skip to main content. K-5 GeoSource. PDF version. Learn More. What are weather observations?
0コメント