Hope it helps!

http://www.thefreedictionary.com/electric arc

electric arc
An electric current, often strong, brief, and luminous, in which electrons jump across a gap. Electric arcs across specially designed electrodes can produce very high heats and bright light, and are used for such purposes as welding and illumination in spotlights. Unwanted arcs in electrical circuits can cause fires. Lightning is a case of an electric arc between one cloud and the earth or another cloud, as are sparks caused by discharges of static electricity.

Furthermore, the generation of electric arcs constitute a potential hazard and might cause vessel rupture and/or explosions if flammable compounds are...

Leakage current dries the layer in some high-current density zones, and conditions promote the generation of electric arcs which short-circuit the dry zones...

...into consideration and try to eliminate the risk of electric flash-over causing the formation of electric arcs in the cap of the electric lamp bulb.

See the following website:
http://electronics.howstuffworks.com/surge-protector3.htm
"Power Surges
Power surges occur when something boosts the electrical charge at some point in the power lines. This causes an increase in the electrical potential energy, which can increase the current flowing to your wall outlet. A number of different things can cause this to happen."

see link below

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Introduction

Every year there are thousands of home fires all across the nation due to faulty household electrical wiring. There are an annual average of 110 electrical fires a day as a result of frayed wires, loose electrical connections, broken extension cords, faulty switches and outlets and other common sources. The Consumer Product Safety Commission states that there were 40,300 fires in 1997 as a result of Electrical Distribution Equipment. There were also some 250 deaths and 1,360 injuries with a total of $687.3 million dollars worth of property damage resulting from these types of electrical equipment failures. Estimates of over 50 percent of these fires are caused by low level arcing faults in typical household wiring. Low level ARCING can generate enough heat and sparks to produce ignition of nearby flammable materials and cause major damage in the form of electrical fires. The National Fire and Protection Agency reports that fixed home wiring causes one third of all electrical fires, additionally, electrical cords and plugs caused one sixth of all home electrical distribution fires and one third of the related deaths.

What is an ARCING FAULT exactly?
General Electric defines an arc fault as "an unintentional electrical discharge characterized by low and erratic current that may ignite combustible materials." These unintentional discharges are what produce the "arcs and sparks" necessary to generate house fires. Arc faults can occur in damaged wiring and electric cords, or in or near a light switch or outlet box. The electrical discharge can either be a Parallel Fault (ARCING between the line and neutral conductors), a Series Fault (e.g. broken wire, faulty switch, loose connection, or other single wire condition) or an Arcing to Ground (e.g. loose wires, shorts to ground, frayed wiring abrading metal, etc.). Any of these faults can produce the heat and sparks necessary to cause a home to be completely destroyed by fire.

http://www.expertlaw.com/library/fires/home_fires.html

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Arcing horns

Arcing horns form a spark gap across the insulator with a lower breakdown voltage than the air path along the insulator surface, so an overvoltage will cause the air to break down and the arc to form between the arcing horns, diverting it away from the surface of the insulator.[3] An arc between the horns is more tolerable for the equipment, providing more time for the fault to be detected and the arc to be safely cleared by remote circuit breakers.

http://en.wikipedia.org/wiki/Arcing_horns

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arcing

1 : to form an electric arc 2 : to follow an arc-shaped course

http://www.merriam-webster.com/dictionary/arcing

The number of hits for this kind of wording is much higher than for "appearance" or "generation".

A "power surge" doesn't necessarily imply the formation of an "electric arc".