We are all familiar with waves, having seen them in the sea.

To see that they carry energy, think about when waves hit a cliff - the wave is stopped and you hear a big crash, with water flying high into the air. The energy to do this has been carried by the wave.

The biggest waves you can get are tidal waves. The Japanese call these waves tsunamis, and in this picture the Japanese artist Hokusai has depicted a tsunami seen off the coast of Kanagawa in Japan in the 19th Century. It certainly gives a strong impression of the great power that can be stored in waves.

For us to heat up the solar atmosphere, we want waves to rise up from the Sun's surface and crash into the corona, where their energy is dumped, heating the gas, just like sea waves crashing onto the shore.