Weather vs. Climate
Weather is the day to day conditions in our atmosphere.
- Sunny
- Precipitation
- Windy
- Tornados, hurricanes, etc.
Weather also includes temperature, air pressure, humidity, wind, etc.
We base our day to day activities on weather.
Weather can change quickly but follows predictable patterns.
Climate is the average conditions for an area over a period of time. This can be over a season or over a number of years.
There are three main climate zones:
- Tropical- This area is between the Tropic of Cancer and the Tropic of Capricorn, along the equator.
- Temperate- 4 seasons (This is where we live.)
- Polar- at the poles (North and South Poles)
Biomes are often identified by climate.
- Dry
- Humid
- Tropical, etc.
Climate phrases may include words like: average, typically, generally, usually, normally, over time, etc.
Wind
Wind is produced by the uneven heating and cooling of the Earth produces the wind.
- As the sun warms the Earth's surface, the atmosphere warms too. Some parts of the Earth receive direct rays from the sun all year and are always warm. Other places receive indirect rays, so the climate is colder.
- Warm air is less dense than cold air and rises higher in the atmosphere. Then cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow. For example.....
There are two types of breezes along coastlines.
- Sea Breeze- occurs during the day
The sun warms up land more quickly than water, and warms the air above the ground. The warm air expands and rises and cool air comes in from the sea to replace the rising warm air.
- Land Breeze- occurs at night
The air also cools faster above the land than the sea, so at night the air above the water is hotter and rises. The cooler air above the land now goes out to sea to replace the rising air here. These predictable patterns make coast lines a great place to harness wind energy!
Clouds
There are 4 base categories for classifying clouds. These names can be combined to form at least 10 different types of clouds.
Cumulus
Like all clouds, cumulus clouds are made of tiny droplets of water. They are tall and puffy. Some can look like towers. Some can look like cauliflower. When sunlight hits these clouds, they look bright white.
Stratus
In stratus clouds, water droplets collect into flat shapes like pancakes. The "pancakes" can be thick or thin. They can stack up like the layers in a cake. But they are not round like cakes — the edges can take on different shapes.
Cirrus
In cirrus clouds, water droplets collect to form thin curves with no clear shape. They look like curls of hair or string. You can see a lot of sky through the holes in these clouds. Cirrus clouds are found high in the sky (at about 18,000 feet or above). At this height, most of the water droplets in clouds turn to tiny pieces of ice.
Cumulonimbus
The cumulonimbus clouds can't hold all their water droplets. When droplets join together, they form bigger drops. These drops can become so heavy that they fall as rain, snow, or hail. These clouds look tall, puffy, and gray. They may bring thunder and lightning.
The Study of Weather and Weather Maps
The study of weather is called Meteorology.
A meteorologist is a scientist that studies weather and the atmosphere. They use scientific principles to explain, understand, observe or forecast the earth's atmospheric phenomena.
Thermometers are used to measure air temperature
Anemometers are used to measure wind speed
- Changes in wind speed indicate weather changes.
Barometers measure air pressure.
- High pressure indicates fair or clear weather.
- Low pressure indicates stormy weather.
A Wind Vane is used to determine wind direction.
Meteorologists use weather maps to share information about weather.
Weather can be viewed and described using a weather map with weather symbols.
Weather symbols are used to tell us about precipitation, warm fronts, cold fronts, high pressure, low pressure, etc.
Warm fronts = warm, moist air from the tropics
Cold front = cold, dry air from the poles – often brings storms
Stationary fronts = no air movement – warm air vs. cold air. They often cause lingering rain storms.
Weather maps show the day to day weather.