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The northern lights

The Northern lights occur when the sun gives off high-energy charged particles (also called ions) that travel out into space at speeds of 300 to 1,200 kilometres per second. A cloud of such particles is called plasma. The stream of plasma coming from the sun is known as solar wind. As the solar wind interacts with the edge of the earth's magnetic field, some of the particles are trapped and they follow the lines of magnetic force down into the ionosphere, the section of the earth's atmosphere that extends from about 60 to 600 kilometres above the earth's surface.

Mammatus clouds

Also known as mammatocumulus, meaning "bumpy clouds", they are a cellular pattern of pouches hanging underneath the base of a cloud.

Penitentes

These amazing ice spikes, generally known as penitentes due to their resemblance to processions of white-hooded monks, can be found on mountain glaciers and vary in size dramatically.

Red tides

More correctly known as an algal bloom, the so-called Red tide is a natural event in which estuarine, marine, or fresh water algae accumulates rapidly in a water column and can convert entire areas of an ocean or beach into a blood red colour.

Sailing stones

The mysterious moving stones of the packed-mud desert of Death Valley have been the centre of scientific controversy for decades. Rocks weighing up to hundreds of pounds have been known to move up to hundreds of yards at a time. Some scientists have proposed that a combination of strong winds and surface ice account for these movements. However, this theory does not explain evidence of different rocks starting side by side and moving at different rates and in disparate directions. Moreover, physics calculations do not fully support this theory as wind speeds of hundreds of miles per hour would be needed to move some of the stones.

Fire whirls

A fire whirl, also known as fire devil or fire tornado, is a rare phenomenon in which a fire, under certain conditions --depending on air temperature and currents--, acquires a vertical vorticity and forms a whirl, or a tornado-like effect of a vertically oriented rotating column of air. Fire whirls often occur during bush fires. Vertical rotating columns of fire form when the air currents and temperature are just right, creating a tornado-like effect. They can be as high as 30 to 200 ft tall and up to 10 ft wide but only last a few minutes, although some can last for longer if the winds are strong.

Gravity waves

The undulating pattern of a Gravity wave is caused by air displaced in the vertical plain, usually as a result of updrafts coming off mountains or during thunderstorms. A wave pattern will only be generated when the updraft air is forced into a stable air pocket. The upward momentum of the draft triggers into the air pocket and causes changes in the atmosphere, altering the fluid dynamics. Nature then tries to restore the fluid changes within the atmosphere, which present in a visible oscillating pattern within the cloud.

Ice circles

A rare phenomenon usually only seen in extremely cold countries, scientists generally accept that Ice circles are formed when surface ice gathers in the center of a body of water rather than the edges. A slow moving river current can create a slow turning eddy, which rotates, forming an ice disc. Very slowly the edges are ground down until a gap is formed between the eddy and the surrounding ice. These ice circles have been seen with diameters of over 500 feet and can also at times be found in clusters and groups at different sizes.

Incredible natural phenomena