Antarctic Ice Melt – Sea Level Rise on Coral Islands
GeographyRegions & CountriesAges 12–13
Use it with your class: students open it from a link or a QR code, with no account needed.
Next in Regions & Countries
A map of Antarctica seen from the South Pole: the continent is covered by a thick ice sheet, ringed by sea ice that expands in winter and shrinks in summer. Set how much global temperature rises, then press Run to advance through the years: sea ice shrinks, the ice sheet thins, and sea level rises, all tracked on the chart below. The panel on the right shows a low Pacific coral island (Oceania) just a few metres high: wherever the water reaches, that part of the island floods and turns saline.
Lesson: Antarctica's natural environment; climate change and sea level rise in Oceania
What it shows
Antarctica holds most of the world's land ice in an ice sheet averaging about 1,700 m thick, surrounded by sea ice that grows each winter and shrinks each summer. Melting sea ice barely changes sea level, because floating ice already displaces its own weight of water; ice lost from the land, together with the thermal expansion of warming seawater, is what raises the ocean. In this model the rate of sea level rise increases with global warming, so higher temperature scenarios give faster rise, and a low coral island shows how a few tens of centimetres can flood land and turn freshwater salty.
How to use
Set the Global temperature rise by 2100, press Reset and let the years run while you watch the sea ice ring, the percentage of ice sheet remaining and the sea level chart. Keep Show Pacific coral island on to see how much of the island floods. Repeat with a low value such as 1 °C and a high value such as 4 °C, and compare the sea level reached in 2100.
Parameters you can change
- Global temperature rise by 2100 0–5 °C
- Starting year 2025–2150 year
- Show Pacific coral island
- Simulation speed 0.5–15 years/s
Questions to explore
- How much higher is sea level in 2100 with a 4 °C temperature rise than with a 1 °C rise?
- How does the summer sea ice area change as the temperature rise increases?
- Why are low coral islands in the Pacific among the first places harmed by sea level rise?
