The Coastline Paradox About this video How can one coastline be
two different lengths? The coastline of Australia is thought to
be roughly 12,500km long. But The World Factbook claims the
figure is more than double this, at 25,700km. This ambiguity
over the length of a coast is known as the coastline paradox.
The length of a coastline depends on the level of detail at
which you measure it. Using a long measuring stick that sweeps
across jagged stretches of coastline will give you a short
coastline length. Conversely, a shorter measuring stick that
enables you to measure inside every inlet along the coast will
calculate a longer length of coastline. So what length of
measuring stick should we use? In this video Derek Muller
relates the coastal paradox to the Koch Snowflake – a shape made
from layer upon layer of equilateral triangles. This type of
shape is called a fractal, which means it looks similar on many
different scales. Coastlines have a fractal structure too; when
we zoom in they look roughly the same