# Important Terms in Weather and Climate

Important Terms in Weather and Climate are the basic terms that are used in describing the weather or climatic conditions of any place.

#### Wether vs Climate

Weather is the atmospheric condition of any place over a short period of time and the average weather conditions of that place for a long period of time is called climate.

##### Factors affecting Climate

> Latitude (Distance from the Equator)
> Altitude (Height above sea level)
> Distance from the Sea
> Speed and direction of winds
> Amount of moisture in the air

##### Elements used to describe weather and climate

> Temperature
> Atmospheric pressure
> Density of air
> Wind
> Humidity
> Precipitation (Rain)
> Topography

##### Temperature

Degree of hotness or coldness of any object is called its temperature. Temperature is the heat energy associated with any object.   Temperature is measured on many scales. A few popular ones are:
> °C (degree Celsius)
> °F (degree Fahrenheit)
> K (Kelvin)

The temperature of any place is dependent upon the amount of heat received by that place from the Sun. The more heat received by a place, the hotter the place will be. and vice-versa.

##### Atmospheric Pressure

Atmospheric pressure or simply pressure is the force applied by the air or gases on any object area. We all are pushed by air from all sides. So the force exerted by the air on a body (area) is called pressure.   The pressure at any place tells us how much force is exerted by air at that place. The more the gases, the higher the will be pressure.   Below are some popular units used to measure pressure:

> Pascal
> Newton per meter square (N/m^2)
> Dyne
> atm

The pressure is also dependent upon temperature. Higher the temperature, lower the pressure. and low-temperature areas will have higher pressure.

### Air Density

Air density is the amount of gases that are present in a particular volume. How much mass of the gases is present in a place. More the gases at a location, the higher the air density.   Due to gravity, most of the gases are found near the Earth’s surface. Hence air density is more near the earth’s surface.   Density is measured as the mass per unit volume i.e. d = m/V  (kg/m^3)

### Wind

The wind is the flow of air. Air flows from the higher pressure area to the lower pressure area. More is the difference in pressure, higher is the speed of winds.   Wind speed is proportional to the pressure difference between two places.

How do winds affect the climate of any place?

> If the winds are coming from hot areas then they will bring the heat with them and the climate will become hotter.
> If winds are coming from cold areas then they will make the weather and climate cooler.
> If winds are coming from the seaside then they will be full of moisture. That can cause rainfall.

##### Humidity

Humidity is the amount of moisture in the air. Water is evaporated by the heat of the Sun. This water vapor rises and becomes part of the air and clouds are formed.   These clouds move with winds from one place to another place and carry water vapor with them. Whenever the temperature of the water vapor decreases then it condenses and rainfall can happen.   So the amount of moisture carried by air is directly responsible for the amount of rainfall in any area.