How forecasts are made and why they are uncertain
Grade 9 Science Worksheet - Building Confidence
Circle the best answer.
A forecast card reading 40% beside a 60% chance of none. NWS: what does a 40% chance of rain mean, by Ari's reading?
- A 40% chance that the spot gets at least 0.01 inch of rain
- Rain will cover 40% of the area
- It will rain 40% of the day
- It will not rain
Town A has a 20% chance of rain and town B a 60% chance. How many times greater is B's chance, by Kira's math?
- 1.2 times
- 80 times
- 40 times
- 3 times
Read this first
Forecast accuracy (NOAA)
Forecast length About how often right 5 days 90% 7 days 80% 10 days or more about 50% About how often is a five-day forecast right, by Jun's reading (NOAA)?
- About 50% of the time
- About 10% of the time
- Each time, with no misses
- About 90% of the time
Why do forecasts get less certain further ahead, by Milo's reading (NOAA)?
- The Sun changes after a week
- Small errors in the estimates grow as the atmosphere keeps changing
- Forecasters stop working after 5 days, so later days are just guessed at
- Models run faster further out
What do computer weather models use to calculate the future, by Noah's reading (NOAA)?
- Random numbers
- Math equations that describe how the atmosphere moves
- The average of last year's weather
- Old almanac guesses
What must a model know before it starts, by Pia's reading (NOAA)?
Use the picture in question 5.
- Next week's weather
- Nothing; it starts from zero
- The climate of the last century
- The current state of the atmosphere, from observations
Which sources give weather models their starting data, by Ren's reading (NOAA)?
Use the picture in question 5.
- Weather balloons, satellites, surface stations and aircraft
- Old forecasts, by themselves, copied forward again and again
- Newspapers and almanacs
- Climate normals, by themselves
What is the main difference between weather and climate, by Tala's reading (NOAA)?
- Weather is rain, and climate is temperature
- Time: weather is now, and climate is the average over years
- They are the same thing
- Place: weather is local, and climate is in space
Over how many years are climate normals averaged, by Zee's reading (NOAA)?
Use the picture in question 8.
- 1 year
- 300 years
- 5 days
- 30 years
Which statement is a weather forecast rather than a climate statement, by Esme's reading?
Use the picture in question 8.
- This city's 30-year normal rainfall is 900 mm
- Summers here average 30 °C
- Winters here are usually dry
- Rain is likely tomorrow afternoon