Volcanic Ash

It is from a volcanic eruption, that fine particles of mineral matter disperse long distances, by winds aloft. These fine particles are termed as volcanic ash. Astonishingly, its chemical composition can critically affect aircraft and machinery, both in air as well as on the ground.

If thick volcanic ash is blown into the atmosphere layers, stratosphere in particular, the global temperature could decrease. It is mainly composed of small tephra; bits of pulverized rock formed by eruptions. These bits are as less as 2 mm in diameter. The following section describes its formation.

Research states that there are three mediums of formation of volcanic ash:

• Gas release under decompression, thus, resulting in magmatic eruptions.

• Propagation of entrained particles throughout steam eruptions, thus, resulting in phreatic eruptions.
• Thermal contraction from freezing in case of water contact, thus, resulting in phreatomagmatic eruptions.

Volcanic ash is so strong that it can lead to problems in breathing, as well as failure in machinery. Aircraft have a hard time combating ash clouds, as weather impressions change enormously.

When one sees a volcanic eruption, the plume seen above the erupting volcano comprises mainly steam and ash. As a result of air and thrust, the minute particles are carried for miles. When they rest at a particular place, they set out as a layer of dust, across the entire land.

Needless to say, this is known as ashfall, and it is in the form of a powder. However, during an eruption, if liquid magma is propagated in the form of a spray, the particles of the magma tend to solidify in the air, in the form of minute fragments of volcanic glass.

Volcanic ash is abrasive in nature, and does not dissolve in water. When wet, it is a fantastic conductor of electricity.

Post eruptions, volcanic ash particles stay in the troposphere for a long time. However, the minute tephra particles have residence time in the stratosphere, for a couple of months only, resulting in climate change, and turning the sky hazy or pale yellow in tint.

When ashfall becomes dense, it can even turn the sky gray, and pitch black in some cases, thereby, restricting visibility. Naturally, temperature slumps down, and a strong smell of sulfur prevails in the atmosphere.

Thunder and excessive lightening are other effects. When such is the case, if at all rainfall occurs, it turns into slippery mud, leading to failure in communication and power supply.

When serious a volcanic eruption hits an area, no one is left unexposed to it. In this case, some adopted measures can save lives. For example, in the form of ashfall, it should never be inhaled deeply. Clean-up activities should be quick, and co-operative.

Public awareness should be spread at the earliest, so that people prepare themselves for relevant clean-up activities in their households. Lastly, it is advisable to be aware of the hazards and occurrences, and be prepared for the worst. Natural disasters take away a lot with them.

However, when one knows what to expect from it, and what measures are to be taken, damage is much less than what was expected.