Why does it rain? (think back to work on the water cycle.)

Write a brief description of how it rains, use the words to help you (but they’re not in order!!) Condensescoolsvapour cloudsprecipitation Risesheats

There are 3 ways rain or precipitation is produced…

Convectional Rain

This form of rain is common in the east of England during the summer. Convectional rainfall 1. The sun heats the ground and warm air rises. 2. As the air rises it cools and water vapour condenses to form water droplets. 3. Water droplets join together to form clouds. 4. Heavy rain storms occur.

Relief rain

Relief rainfall Relief rain is formed when air is forced to cool as it rises over relief (height) features in the landscape (hills or mountains). 1. Air is forced to rise and cools by 1°C per 100m. 2. As the water vapour in the air condenses, it forms clouds and rains. 3. The air starts to descend and begins to warm up again. 4. As air warms up, it can hold more water vapour - clouds disappear and rain stops. This side is known as a RAINSHADOW.

Frontal rain

1. An area of warm air meets and area of cold air. 2. The warm air is forced over the cold air 3. Where the air meets the warm air is cooled and water vapour condenses. 4. Clouds form and precipitation occurs. Frontal Rainfall

Make a copy of all three types of rainfall, and explain what happens at stage 1, 2, 3 and 4 for each of them.

Copy and complete: I know how it rains. Firstly warm _____ rises because hot air is lighter than cold air. As it rises it ________. This makes condensation. We see this in the sky as ________. When the clouds get to a certain point they can hold no more _________. This is when it ______. Relief Rainfall. Relief rainfall happens when the air is forced to ______ as it hits the mountain. As it rises it_______, forms clouds and then it _______. WATER RAIN COOLS CLOUDS COOLS RAINS AIR RISE

Cloud cover is measured in Oktas. Today there are _______ Oktas of cloud.

We know there are many different types of cloud, because not all cloud looks the same. You might see more than one of these types of clouds in the sky all at once.

These are the main types of cloud: Cirrus clouds are wispy, like a lock of hair, and are high up. Cumulus means ‘heap,’ cumulus clouds look a bit like cotton wool balls Stratus clouds are layers, and are middle to low clouds. Cumulonimbus clouds are tall and dense, usually resulting in rain or storms.

Any cloud with the word cirro or cirrus is a high cloud. Any cloud with the word alto in it is about in the middle. Any cloud with nimbo or nimbus added onto it means it is producing precipitation.

Add labels to your diagram of the clouds.

Type of CloudAppearanceAltitude (height) Cumulo-nimbus =Thunderheads Can cause lightning, thunder, hail, strong rains, strong winds, and tornadoes Near ground up to 75,000 feet (Vertical clouds) Cirro-stratusThin, wispy, appears in sheets. Located above thunderheads Above 18,000 feet (High-altitude clouds) CirrusThin, wispy, filamentous, or curlyAbove 18,000 feet (High-altitude clouds) Cirro-cumulusSmall, puffy, patchy and/or with a wavelike appearance Above 18,000 feet (High-altitude clouds) Alto-cumulusMedium-sized puffy, patchy, scattered clouds - often in linear bands 6, ,000 feet (Middle-altitude clouds) Alto-stratusThin, uniform6, ,000 feet (Middle-Alttude clouds) Strato-cumulusBroad and flat on the bottom, puffy on top,Below 6,500 feet (Low-altitude clouds) CumulusPuffy and piled up.Below 6,500 feet (Vertical clouds) StratusUniform, flat, thick to thin layered clouds will ill-defined edges Below 6,500 feet (Low-altitude clouds) Nimbo-stratusUniform, dark, flat, low, featureless clouds that produce precipitation Below 6,500 feet (Low-altitude clouds)

alto-cumulus - Middle-level, medium-sized puffy clouds. alto-stratus - Middle-level, layered clouds. cirro-cumulus - High-altitude, small, wispy, patchy, puffy clouds. cirro-stratus - High-altitude, thin, wispy clouds in layers. cirrus - High-altitude, thin, wispy clouds. cumulo-nimbus- Large, dense, towering clouds that cause thunderstorms. cumulus - Low, puffy clouds. fog - Ground-hugging clouds. nimbo-stratus - Low, dark, rain cloud. stratus - Low, layered, horizontal, wispy clouds with a flat base. strato-cumulus - Low clouds, broad and flat on the bottom, puffy on top (higher than cumulus and lower than altocumulus

Now answer the following questions: 1.What are clouds? 2.What is cloud cover measured in? 3.What are the three main cloud types? 4.What name do high level clouds begin with? 5.What types of clouds does convectional rainfall cause?

Cumulus

Cumulonimbus

Cumulonimbus

Cumulus

Cirrus

Stratus

Cumulus

Stratus

Cirrus

Cumulus

Cirrus

Stratus

Cumulonimbus

Cumulus

Cirrus