Physical Processes and the Future of Settlements

Let's start with a question

Tuktoyaktuk is an Inuvialuit community on the shore of the Beaufort Sea in the Northwest Territories. Its shoreline is eroding: storms wear away the land, and thawing permafrost makes the ground softer and easier to wash away. Some buildings near the shore are at risk, and the community is planning for the future.

In Grade 7 you learned how physical processes such as plate movement, erosion and climate shape the Earth. In this lesson you'll analyse how those processes may affect where and how people live in the future.

Sea-level rise

As the climate warms, glaciers and ice sheets melt and ocean water expands as it warms, so the sea rises. Settlements most at risk are low-lying coastal cities, river deltas and small, low islands:

• Deltas such as the Ganges–Brahmaputra delta in Bangladesh, home to many millions of people.
• Coastal cities such as Jakarta, Indonesia, where parts of the city are also sinking because so much groundwater has been pumped out. Indonesia has begun building a new capital city on the island of Borneo, partly because of these problems.
• Small island nations in the Pacific, such as Tuvalu and Kiribati, where much of the land is only a few metres above sea level.
• In Canada, Richmond, British Columbia, is built on the low Fraser River delta and is protected by dikes. Coastal communities in Atlantic Canada and the Arctic also face rising water and erosion.

Higher seas also mean that storm surges (sea water pushed onshore by storms) reach farther inland, and salt water can seep into farmland and drinking water.

Stronger storms and flooding

• In 2005, Hurricane Katrina hit New Orleans, a city where much of the land is below sea level, protected by levees. Several levees failed and about 80% of the city flooded. The disaster showed how dangerous it can be to rely on low, reclaimed land behind walls.
• In 2022, Hurricane Fiona (post-tropical by landfall) damaged and destroyed homes in Atlantic Canada and eastern Quebec, including in Port aux Basques, Newfoundland and Labrador.
• In 1954, Hurricane Hazel caused deadly flooding in the Toronto area, killing 81 people. Afterward, many homes on floodplains were not rebuilt; the land became parks, and Ontario's conservation authorities gained the power to regulate building on floodplains. That decision still protects people today.

Earthquakes and tsunamis

More and more people live in cities in earthquake zones. On March 11, 2011, a huge undersea earthquake off Japan caused a tsunami that went over sea walls and devastated coastal towns. Off the coast of British Columbia lies the Cascadia subduction zone, which scientists say can produce very large earthquakes, so B.C. builds and plans for that risk.

Wildfires

Warmer, drier summers can bring more wildfires to the wildland–urban interface. In 2016, a wildfire forced more than 80 000 people to evacuate Fort McMurray, Alberta, and destroyed many homes. In 2024, a wildfire destroyed many buildings in the town of Jasper, Alberta.

Thawing permafrost

In the North, thawing permafrost can make buildings tilt, roads crack and airstrips buckle, and it speeds up coastal erosion, as in Tuktoyaktuk.

Drought and desertification

Growing cities need more water. In 2018, Cape Town, South Africa, came close to "Day Zero", when city taps would have been turned off after a long drought. Strict water saving helped the city avoid it. At the edges of deserts, drought and overuse of land can lead to desertification, making it harder for people to farm and live there.