Cambridge IGCSE Marine Science Practical Skills 2: Ocean and coastal physical measurements

This chapter develops the physical-measurement activities linked to Cambridge 0697 Topics 1 and 2: floating and land-based ice, water density, light penetration, tides and currents. Shore profiles and sediment measurements remain in Practical Skills 5. The six-note organisation is editorial, not a Cambridge unit sequence.

Floating ice and land-based ice

Set up two identical containers with equal initial water levels. In the floating-ice setup, place a measured ice mass in the water. In the land-ice model, support the same ice mass above the water on a mesh or sloped surface so meltwater drains into the container. Mark or measure initial and final levels at eye height after complete melting.

Keep container shape, water volume, ice mass, ice temperature and room conditions constant. A lid with equal openings can reduce unequal evaporation. The floating ice already displaces water, so its melting should cause little change. Land-based ice adds previously supported water and raises the level.

Read the bottom of a water meniscus against a fixed scale and avoid moving containers. The model demonstrates displacement, not every process controlling global sea level.

Measuring density

Density is mass divided by volume. Measure a clean dry container, add a measured water volume, reweigh and subtract the container mass. Then calculate:

$$\rho = \frac{m}{V}$$