Weather and climate, Year 8: more practice

Weather

HintIt can change from hour to hour.

The whyWeather is short-term. Climate is the pattern of weather over many years.

Thirty years

HintA few decades, long enough to smooth out odd seasons.

The whyA long average stops one unusually cold or hot year from distorting the picture.

Climate

HintDoes it describe one day or a long-term pattern?

The whyIt describes a long-term pattern. "It is raining in Manchester today" would be weather.

It rises, creating low pressure

HintWarm air is lighter than cool air.

The whyThe rising air cools and its moisture condenses, which is why the Equator has heavy, regular rain.

Dry, clear weather

HintSinking air warms and cannot easily form cloud.

The whyThis is why many of the world's great hot deserts, such as the Sahara, lie near 30 degrees.

Air flows to even out the difference in pressure

HintThink of air spreading out from where it is crowded.

The whyThe bigger the pressure difference between two places, the stronger the wind.

The sun's rays arrive at a low angle and are spread over a larger area

HintThink about how a torch beam spreads when shone at a slant.

The whyNear the poles the rays are also passing through more atmosphere, so they lose more energy before reaching the ground.

Temperate maritime

HintThe sea has a calming effect on temperature.

The whyThe sea warms and cools slowly, so coastal places have a smaller range of temperature than inland ones. The warm North Atlantic Drift also helps.

The south-facing side

HintThe sun is in the southern half of the sky.

The whyThe direction a surface faces is its aspect. Aspect is one reason microclimates differ over short distances.

The walls give shelter from the wind and store heat

HintThink of what a barrier does to moving air and to sunshine.

The whyShelter reduces wind chill, and brick or stone soaks up warmth by day and releases it slowly at night.