Is there any scientific way to stop a volcano from erupting?

Krishna: There are some ways scientists can think of doing this but really putting them into practice? NO! To date there have been no successful efforts to start, stop or reduce a volcanic eruption. However, ideas exist. Techniques to control an eruption could include depressurization of the magma chamber or increasing the aperture of the vent to diffuse the energy of an eruption (2).

Image source: reference (2)

Previous attempts to do this have failed. There is no way to stop the flow of lava.

Many have tried in the past, including famed U.S. Gen. George S. Patton, who attempted to bomb lava in its tracks (1).

According to the U.S. Geological Survey, Patton was a lieutenant colonel in 1935 when another volcanic erupt... threatened Hilo. In an attempt to save the town, Patton oversaw an operation to bomb the fissure from which the lava was flowing. That attempt failed.

Triggering eruptions by bombing was considered as a means to inflict greater damage on Japan. Although it was never attempted it was certainly discussed, and could therefore be considered a possible engineering solution to an impending eruption in the future (2).

Again in 1973, authorities tried to stop the flow of lava from Iceland's Eldfell Volcano on the island of Heimaey by spraying it with 1.5 billion gallons of ice-cold seawater, hoping the cooling effects of the water would halt the lava. The heat proved too much, and they were unable to prevent the advancement of the lava. They did, however, have some success in diverting the lava from the island's harbor, but they were unable to stop the flow. That eruption killed one person and destroyed portions of several towns (1).

The attempts failed because lava is incredibly hot, at nearly 2,000 degrees Fahrenheit. It's also heavier than it appears because it is basically liquid rock.

Ditches to divert the lava might work, but the cost associated with building the ditches would more than likely exceed the overall costs of any lava damage. So why attempt?

NASA has some plans too to put into practice in Yellow National Park (3). In NASA’s plan, the drawing pin becomes an 8km-deep borehole drilled into Yellowstone’s hydrothermal system. This is the vast body of hot groundwater that surrounds the magma chamber and feeds the springs and geysers. The hydrothermal system absorbs more than two-thirds of the heat generated by the magma.

In NASA’s scheme, huge quantities of cold water would be pumped down the borehole, helping the hydrothermal system suck out even more heat; the idea being that the magma would cool, get stickier, and start to congeal. This, in turn, would mean that it was too viscous to rise towards the surface and feed an eruption.

If Yellowstone were ready to blow, it would need to be cooled by 35 per cent to stop the eruption in its tracks, and this wouldn’t come cheap. NASA estimates the cost would be $3.5bn (£2.4bn). It would take hundreds, or even thousands, of years to accomplish this.

Scientists think this would not be easy, and cautions against doing anything without a detailed study of the pros and cons.

There are dangers involved and there’s the possibility that drilling into a volcano that’s primed and ready to go might trigger the blast it’s trying to prevent. But with the catastrophic consequences for humans of a future super-eruption, it may turn out to be a risk we have to take.

And is there a way to prevent earthquakes by volcanic eruptions? Again the answer is NO! We cannot prevent natural earthquakes from occurring but we can significantly mitigate their effects by identifying hazards, building safer structures, and providing education on earthquake safety. By preparing for natural earthquakes we can also reduce the risk from human induced earthquakes.

These things are easy and cost effective than actually trying to stop volcanic eruptions.

Footnotes:

1. Here's Why You Can't Stop Lava From Flowing | The Weather Channel -...
2. Engineering Volcanoes
3. How to stop a volcano