Lo scioglimento del permafrost nelle Alpi desta preoccupazione per l’aumento del rischio di frane. Un team di scienziati dell’Università di Friburgo ha messo a punto un nuovo metodo di misurazione della sua temperatura, che sfruttando la resistenza elettrica potrebbe consentire di prevedere meglio eventuali scoscendimenti.
Finora si perforava il terreno fino a cento metri di profondità per misurarne la temperatura. Una tecnica che è però complicata e costosa, rileva in una nota il Fondo Nazionale Svizzero per la Ricerca Scientifica (FNS).
Facendo passare corrente continua attraverso il terreno tra due elettrodi e misurandone la resistività elettrica, è invece possibile misurare il permafrost su vaste aree e valutare la quantità di ghiaccio, in modo da permettere previsioni sulla sua evoluzione.
L'instabilità del permafrost
Il Quotidiano 06.11.2023, 19:40
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