The cloud of ash and gases that the La Palma volcano spits out is moving to the rest of the Canary Islands and, according to experts’ forecasts, will cover the Iberian Peninsula this Friday. The gas that generates the most concern is sulfur dioxide, since when it comes into contact with cloud water it can form sulfuric acid and fall as acid rain .
For now, the risk of this happening is very low according to the State Meteorological Agency, but with the expected winds at different heights, “it cannot be ruled out” that acid rain will occur in the east and north of the more mountainous Canary Islands. .
Acid rain: what is it?
Acid rain is what is called a phenomenon that consists of any type of precipitation composed of acids, such as sulfur dioxide . Sulfuric and nitric acids that form in the atmosphere fall to the earth’s surface in the form of rain, although they can also do so mixed with fog, hail and even snow.
The way scientists know whether or not it is acid rain is by measuring the pH of the water . When it is pure, the pH is 7, so this value is taken as a reference. Rain generally has a pH between 5 and 5.5 (slightly acidic). When the pH falls below 5, it is considered acid rain.
Is there a risk to the population?
From the State Meteorological Agency they call for calm since, in the event of acid rain due to the eruption of the La Palma volcano, it would take place as scattered and weak showers , without any risk to health.
For its part, the US Environmental Protection Agency (EPA) ensures that walking in acid rain is no more dangerous for people than walking in normal rain .
However, special care must be taken with the concentration of sulfur dioxide at high levels in the atmosphere because, when this occurs, very fine sulfate particles are formed that can affect the respiratory system, giving rise to symptoms such as: respiratory distress, headache…
Finally, it should be noted that if it is repeated over a long period of time, it can significantly alter ecosystems at a chemical and biological level .
