The Water Cycle, Weather and Climate — Answers
Answer sheet with model answers and success criteria for the Year 9 earth, rocks & weather worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Science · Earth, Rocks & WeatherThe Water Cycle, Weather and Climate — Answers
Part A: The water cycle
Water is constantly moving between the oceans, the atmosphere and the land. The Sun heats water in oceans, lakes and soil, and it evaporates to form water vapour. Plants also release water vapour from their leaves (transpiration).
As moist air rises it cools, and the water vapour condenses onto tiny dust particles to form clouds. When droplets join and become heavy enough they fall as precipitation. On land, water flows over the surface as runoff or soaks in by infiltration, eventually returning to the sea.
Answer: condensation
Clouds are made of billions of these droplets (or ice crystals).
Answer: transpiration
Answer: precipitation
Answer: Runoff is water flowing over the surface of the ground into streams, rivers and the sea. Infiltration is water soaking down into the soil and rock, where it may become groundwater.
- AThe Moon
- BThe Sun
- CEarth's core
- DWind
Answer: The Sun
The Sun's energy heats water so that it evaporates, and it also drives the winds that move water vapour around the globe.
Answer: True
Water is recycled: it changes state and location, but very little is added or lost.
Part B: Air pressure and weather
Air pressure is the push of the air above us. In a high-pressure system, air sinks; in a low-pressure system, air rises. Rising air cools, and cooler air cannot hold as much water vapour, so clouds form. Wind is air moving from high to low pressure.
- AClear skies and settled, dry weather
- BThick clouds and heavy rain
- CThunderstorms
- DStrong, gusty winds and rain
Answer: Clear skies and settled, dry weather
In a high, air sinks and warms, so clouds evaporate and skies are usually clear.
Answer: In a low-pressure area, air rises. As it rises it cools, so water vapour condenses into clouds, which can produce rain.
Answer: From high pressure towards low pressure. The bigger the pressure difference, the stronger the wind.
Answer: As air is forced up the windward side of the mountains it cools, and water vapour condenses to form clouds and rain. By the time the air crosses the top and sinks down the other side, it has lost most of its moisture and warms up, so that side stays dry (a rain shadow).
Part C: Weather and climate data
Weather is the condition of the atmosphere at a particular place and time. Climate is the average pattern of weather in a region over a long period, usually at least 30 years.
Mean monthly data for a town over six months — Month 1: 28 °C, 110 mm · Month 2: 27 °C, 95 mm · Month 3: 24 °C, 80 mm · Month 4: 20 °C, 45 mm · Month 5: 16 °C, 30 mm · Month 6: 13 °C, 20 mm
Answer: 380 mm
- 110 + 95 + 80 + 45 + 30 + 20 = 380 mm
Answer: 63.3 mm
- 380 ÷ 6 = 63.33…
- ≈ 63.3 mm
Answer: Rainfall range 90 mm; temperature range 15 °C
- Rainfall: 110 − 20 = 90 mm
- Temperature: 28 − 13 = 15 °C
Answer: As the mean temperature decreases from month 1 to month 6, the rainfall also decreases: the warmer months are the wettest.
- AIt is raining heavily this afternoon
- BTomorrow will be windy with a top of 18 °C
- CThis region has hot, wet summers and mild, dry winters
- DThere was a thunderstorm last night
Answer: This region has hot, wet summers and mild, dry winters
Climate is the typical pattern of weather in a place over many years (usually 30 or more). The others describe weather on particular days.
Part D: Explain
Model answer: The Sun heats the ocean surface and the water particle gains energy and evaporates, becoming water vapour. It rises with warm air and, as the air cools higher up, it condenses onto a dust particle to form a cloud droplet. Droplets join together until they are too heavy to stay up, and the particle falls as precipitation (rain) onto land. It then flows downhill over the ground as runoff into a river (or infiltrates into the soil and moves as groundwater), and the river carries it back to the ocean.
Success criteria:
- Evaporation caused by heat from the Sun
- Condensation caused by cooling as air rises
- Precipitation when droplets become heavy
- Runoff or infiltration returning water to the ocean
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.