Articles - 'a', 'an' and 'the'

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Predicting volcanic eruptions is never easy. For centuries, volcanologists and seismologists have studied activity beneath Earth that might indicate eruption. Forecasting when volcano might erupt has been somewhat unreliable. However, scientists from NASA and Smithsonian Institution say they are step closer to providing more accurate forecasts of when volcano might blow. NASA used images from space to detect changes in colour of leaves. The research was based on 2019 study from McGill University. This study showed that increase in carbon dioxide levels emitted by two active volcanoes in Costa Rica had impact on colour of leaves in surrounding areas.

Current methods of predicting imminent volcanic explosion include checking seismic activity, changes in ground height, and carbon dioxide and sulphur dioxide emissions. NASA said new method of monitoring changes in colour of foliage from space could help in foretelling eruptions. The science behind this is fairly straightforward. As magma moves upwards through Earth's crust, it releases carbon dioxide. Trees absorb this and their leaves become greener and more vibrant. LiveScience website said: "These signs can help to protect communities against worst effects of volcanic blasts, including lava flows, ejected rocks, ashfalls, mudslides, and toxic gas clouds."

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