Warming oceans, rising seas and melting ice
Grade 9 Science Worksheet

Circle the best answer.
Note: Total 1901–2018, about 0.20 m. At IPCC's 2006–2018 rate of 3.7 mm a year, how much would sea level rise in 10 years, by Bo's math?
- About 0.37 mm
- About 13.7 mm
- About 370 mm
- About 37 mm
Read this first
Use this
A climate chart with ocean heat content and sea level both rising.
NASA: the yearly rate of rise went from 0.20 cm in 1993 to 0.44 cm now. About how many times faster is it now, by Jun's math?
- About 0.45 times
- About 2.2 times
- About 0.24 times
- About 4.4 times
NOAA: from 2005 to 2013, rise from melting was nearly twice the rise from expansion. If expansion added 1 mm a year (model data), about how much did melting add, by Kira's math?
- About 2 mm a year
- About 3 mm a year
- About 0.5 mm a year
- About 20 mm a year
Which melting ice adds new water to the ocean, by Luz's reading (NOAA, NSIDC)?
- Pack ice floating on the Arctic Ocean
- Ice on a frozen pond far inland
- Glaciers and ice sheets on land
- Sea ice, which froze from seawater
A climate chart with ocean heat content and sea level both rising. Model data: a column of seawater warms and expands a tiny amount. What happens to sea level above it, by Milo's reading (NOAA)?
- It rises a little, since the warm water takes more room
- It falls, since warm water shrinks
- It stays the same, since no water was added
- It rises because new ice forms on top
Floating sea ice beside a glacier, an ice shelf and an iceberg. Floating sea ice beside a glacier, an ice shelf and an iceberg. glacier ice shelf sea ice iceberg IPCC AR6: Arctic sea-ice area fell about 10% in March and about 40% in September (1979–1988 to 2010–2019). How many times bigger is September's loss, by Noah's math?
- 50 times
- 30 times
- 0.25 times
- 4 times
Model data: a September sea-ice area of 7 million km² shrinks by 40% (the IPCC AR6 Arctic figure). What area is left, by Pia's math?
Use the picture in question 6.
- About 6.6 million km²
- About 47 million km²
- About 4.2 million km²
- About 2.8 million km²
NSIDC: open ocean reflects about 6% of sunlight, and sea ice 50 to 70%. What happens as Arctic sea ice shrinks, by Ren's reading?
Use the picture in question 6.
- Nothing changes, since ice and water reflect equally
- More sunlight is absorbed, adding warmth
- Sea level jumps, since floating ice adds new water
- The warmer water shrinks, so sea level drops
Use this
A pH scale with a small step down from about 8.2 to about 8.1.
NOAA: average surface pH is now about 8.1, after a fall of about 0.1. About what was it before the industrial revolution, by Zee's math?
- About 8.2
- About 9.1
- About 8.0
- About 7.1
Why does more acidic seawater make it harder for oysters and corals to build shells, by Ari's reading (NOAA)?
- Acidity makes the seawater far too cold
- More carbonate ions crowd out the shells
- A higher pH dissolves the shells faster
- Fewer carbonate ions are free to build shells