Water’s journey

Clouds form as air is pushed upward and cools, and rain and snow start to fall. More heavy water than light water rains out, making heavy water increasingly rare in clouds further inland, and also in the snow that falls there. On the ground, there is more heavy water near the coast than further inland and in the mountains.

The snow pack builds up over the winter season, before it starts melting around April. As the snow melts, water seeps into the ground, into soils, and also into streams and rivers. Water from higher up in the mountains carries less heavy water than at the coast. This allows to find out where the water in the rivers comes from.

The snow pack builds up over the winter season, before it starts melting around April. As the snow melts, water seeps into the ground, into soils, and also into streams and rivers. Water from higher up in the mountains carries less heavy water than at the coast. This allows to find out where the water in the rivers comes from.

Winds and the sun drive water out of the ocean and into the air. Evaporation is particularly strong when cold air from the sea ice or land gets swept over the warmer ocean waters.  Heavy water lags behind in the ocean, making it more rare in the air.

Groundwater may follow several different paths, seeping into waterways, lakes and oceans or into aquifers. Some water in lakes, rivers and streams is carried back to the oceans, or is evaporated back to the atmosphere.

When water reaches the ground, it can evaporate back into the atmosphere from the land surface, and from the surface of tree leaves and other vegetation.

Storms form where warm and cold air meets. Winds become stronger, and sweep together moist air from near and far. Eventually, some storms meet the coast of Scandinavia. Heavy and light water changes little while being transported, keeping an imprint of its origin.