A huge chunk of the Cumbre Vieja volcano, on the Canary Island of La Palma, is on the move. In 1949 this mass of rock — perhaps as large as the Isle of Man — dropped 4m seawards and stopped.
Monitoring in the mid-1990s suggested that it was continuing to creep downslope, though only at a centimetre a year. At some time, however, and we don’t have a clue when, the landslide will plunge into the north Atlantic, generating gigantic tsunamis — sea waves likely to be 50m high or more — that will devastate the Caribbean and eastern United States, as well as the Canaries, southern Europe and western Africa. Without evacuation, the destruction will end the lives of tens of millions and bring the global economy to its knees.
You might expect that this landslide would be one of the most closely studied on the planet, but that would be far off the mark. In reality, nobody is monitoring the situation and the island’s authorities are reportedly allowing new building developments to go ahead.
Why does nobody care? In the second half of the 20th century we planned for the nuclear winter that would follow an atomic exchange, but we now give little thought to the similar conditions that would certainly prevail after an asteroid impact or volcanic super-eruption. Even now, it is all the rage to hold nanotechnology and exotic physics experiments gone wrong as harbingers of doom, while regarding the certain threat of natural catastrophes with either a snort of disdain or a bellow of laughter.
Despite existing, and indeed thriving, on planet Earth purely as a consequence of nature’s benign consent, it seems that humanity has a blind spot when it comes to addressing what will happen when that consent is withdrawn.
The Earth has been around for a very long time — something approaching 4,6-billion years. Business as usual involves serious pounding by asteroids and comets, the rending of the crust by gigantic outpourings of lava and the battering of the ocean-basin margins by enormous waves climbing to heights in excess of 100m. In the blink of an eye that humans have been recording their experiences, it is hardly surprising that we have yet to witness one of these global geophysical events (or gee-gees, as they are becoming known). But they are not going to stop happening.
In any single year it is extremely unlikely that any of us will succumb to a volcanic super-eruption or a direct hit from an asteroid, both events that have the potential to kill about one in six of the world’s population.
A collision with an asteroid large enough to cause global mayhem happens only once every hundred millennia, while a gigantic volcanic blast occurs perhaps every 50 000 years. They are, however, certain to happen. Both trigger rapid and severe global cooling that, apart from the absence of radiation, is comparable to the nuclear winter that would follow an all-out exchange of atomic hardware.
Following the last super-eruption — 73 500 years ago, at Toba in Indonesia — the entire planet may have been plunged into darkness for several years, with bitter cold destroying plant life and wiping out most of our predecessors — leaving behind just a few thousand from whom all of us are descended. How would we cope in such a situation today?
The easy option is to lie back and relax, secure in the knowledge that, statistically, we probably won’t be around when the next gee-gee strikes.
Others will be, however — and if not our children or grandchildren, then certainly their descendants. And if they hold to the current line of thinking, they will be no better prepared than we are.
But what can we do? Worrying ourselves to sleep every night or launching a global war on nature is clearly not the answer. We can, however, begin a serious horizon-scanning exercise, looking further than the next election or international trade treaty to the global catastrophes we must face at some point in the future.
To some extent, this has already started, with scientists worldwide making a concerted effort to spot all the Earth-threatening asteroids in the next few decades. But we have barely scratched the surface in trying to understand and assess the threat posed by other potential gee-gees. Of about 3 000 active and potentially active volcanoes, for example, we are monitoring just a few hundred. A volcano in the remote southern Andes could have been building towards a super-eruption for many decades, but we would know nothing about it until it blew itself apart.
The situation on La Palma demonstrates that even when we are aware of a potentially devastating threat, we seem to prefer to ignore it in the hope that it will mysteriously disappear. Clearly, however, it won’t, and it’s about time that we sat up and paid attention to what nature can and will do.
A wild-haired physicist wearing odd socks could be cooking up a black hole in his laboratory this very minute, but then again he or she almost certainly isn’t. Meanwhile, lurking somewhere out in space or closeted beneath the Earth’s crust, there is a large rock or a heaving mass of magma with your name on it — or if not yours, then certainly one of your descendants. — Â