You
say Vesuvius, I say... Vesuvius the classical name; Vesuvio in modern
Italian.
You
can climb it, but it's a long way. Buy a bus ticket at the Pompeii
Sclavi station on the Circumvesuviana railway. The bus takes you
about half-way. (Incidentally, the countryside around here is
incredibly messy: rubbish, domestic and building, gets dumped
everywhere.) Half-way up you transfer to a bus-jeep which takes you
lurching up through the beautiful National Park forest. When that
peters out you climb the last ten minutes up to the crater. Vesuvio
is about 4,000 feet. My water bottle exhales a brief sigh as I open
it.
A
short lecture from a volcanologist (included in the ticket), and you
are free to wander around. Go early: it gets crowded. It's a huge
hole in the ground. Not much more really, but really huge, awesome, with vertical sides, a massive 600 metre-wide cannon. In the
last eruption (1944) it managed to block its vent with 8km of rock.
But the magma chamber is still there below that, and as the pressure
builds up, more gas is produced. All you can see on the surface are a
few faint whisps curling into the morning sun. Look closer and you
see deposits around the vent, foul-looking yellow and brown: a
message from the inside of our beautiful planet.
Before
1944 it used to have minor eruptions every 20-odd years, but now it's
blocked its own vent. It could erupt from the side, which has
happened before. With all that gas and magma building up, pyroclastic
flows are likely, travelling at up to 100 miles an hour at 600
degrees celsius. Or it could simply blow its top off. Last time that
happened on any scale was the Indonesian Tambora in 1815. It was
heard up to 1,000 miles away. Naples
is hardly 1,000 miles from London, but in
Indonesia the sound would have travelled across the sea: travelling
across land, and the Alps, would probably reduce the bang. In
1816 there was no summer. The
temperature hardly got above freezing.
But
the real threat might not be Vesuvio but the Campi Flegrei ('flaming
fields') caldera, a 'supervolcano' a few kilometers west of Naples.
The Vesuvio vent is 600 metres across. The Campi Flegrei caldera is
13 kilometers across. Much of it lies under the bay of Naples. The
earth goes up and down, there are vents and frequent tremors. Between
1968 and 1972 it rose more than 1.2 metres, and in
the mid-80s the entire area was evacuated, but there was no eruption.
The earth started to subside. Over the past eight years it's been
rising again. Scientists have been trying for years to get the
consent of the Naples authorities to drill down into it to find out
what is going on, but there has been concern that drilling into it
could precipitate an eruption. Fears seem to have been put to rest,
and I believe drilling is beginning. Campi Flegrei was regarded by
the Romans as the mouth of hell.
The
effects of a major eruption in Europe would put any damage to the
economy by bankers, speculators, the last government (whichever one
it was), in the shade, in some very deep shade indeed, not to mention under
the covering of a thick blanket of ash. The loss of life could be
horrendous. In the Naples area there are plans for the emergency
evacuation of some 300,000 people, but 4.5 million people live in
that area. The chaos of 3 or 4 million people fighting to escape. &
the likely damage seems to be calculated on prevailing wind
direction, so check which way the wind's blowing before you visit. I
certainly wouldn't want to live in the area. I've been in a few minor
tremors and I wouldn't want to feel the ground shaking under my feet
in Pompeii.
...a huge hole in the ground: yes, those are trees on the scree slope inside. |