Climate change may stir geological mayhem

Climate change may stir geological mayhem

For more books and arts coverage and to add your comments, visit Beasts are stirring Climate fluctuations can trigger dan...

514KB Sizes 0 Downloads 26 Views

For more books and arts coverage and to add your comments, visit

Beasts are stirring Climate fluctuations can trigger dangerous rumblings below, Fred Pearce learns rapid climate change, for instance, when we shifted in and out of ice ages. The stresses and strains of rising and falling sea levels and the creation and loss of ice sheets triggered these outbursts. Climate change, he says, may already be shaking up the Earth anew.

IN 2006, London geologist Bill McGuire argued in New Scientist that global warming would trigger epidemics of volcanic eruptions, earthquakes and tsunamis. Now he’s written the book. The story is even scarier writ large. The world as McGuire sees it in Waking the Giant sometimes seems more ancient myth than modern science. It is one where subterranean events are intimately linked to those above ground, and we are awakening primordial monsters. There is now abundant evidence that catastrophic outbursts of geological activity accompanied past periods of

Life on the wing Bird Sense: What it’s like to be a bird by Tim Birkhead, Bloomsbury, £16.99 Reviewed by Jamie Condliffe

EVER wondered what it might be like to be a bird soaring through the skies? You’re not alone. You need only consider a handful of metaphors – bird-brained, hawk-eyed and pigeon-toed – to see how our feathered friends permeate our thinking and drive our curiosity. So what would an

Volcanoes tend to react badly to drastic changes at Earth’s surface


Waking the Giant: How a changing climate triggers earthquakes, tsunamis, and volcanoes by Bill McGuire, Oxford University Press, £18.99/$29.95

During the last ice age, the weight of ice suppressed volcanic eruptions. When the ice melted the land surface lifted, sometimes by hundreds of metres, reducing pressure below and turning solid rock to liquid magma. The pent-up rage of the Earth was released. As the ice age faded, the number of volcanic eruptions grew 50-fold. Global warming threatens a reprise. McGuire explains that volcanoes “are primed systems

avian existence be like? moves deftly from playful In Bird Sense, Tim Birkhead, anecdote to scientific fact. a zoologist at the University of It’s these facts that make up Sheffield, UK, attempts to get the most interesting parts of the to the bottom of that question. book. Birkhead describes, for It’s an impossible dream, of example, ducks that keep half of course, but by examining a their brain awake during sleep so bird’s basic senses, he manages they can still spot predators. Then to provide a real flavour of life there are the great grey owls that from a bird’s-eye view. pinpoint their rodent prey using Birkhead’s writing is asymmetric ears, and American wonderfully flavoured by his kestrels that can home in on own insights and experiences. His insects from an impressive tales – which range from skinny18 metres. Such observations dipping in New Zealand to caring for a blind pet zebra finch – make “By examining a bird’s basic senses, Birkhead provides the book a pleasure to read. a real flavour of life from That is not to say the book is lightweight, though, and Birkhead a bird’s eye view”

constantly teetering on the edge of stability and highly sensitive to minuscule changes to their external environment”. He is not just talking about geological timescales. The Earth changes shape with the seasons as water shifts hemispheres, squashing or releasing the land beneath. It squeezes magma like toothpaste in a tube. In the northern hemisphere, November to April is volcano season. As shifting ice and water destabilise hidden faults in the Earth’s crust, earthquakes join this dance of giants. In recent decades, we have seen an “unprecedented cluster of massive earthquakes”, McGuire notes. Since 1900, seven have exceeded magnitude 8.8. Three “megaquakes” off Sumatra, Chile and Japan ripped the Earth apart in the past seven years alone. It could be that something is afoot. Six years ago, McGuire suggested shrinking glaciers in New Zealand’s Southern Alps might trigger an earthquake. Cue Christchurch last year. The climate, we know, has been unusually stable in the past 10,000 years. That meant the world was more geologically stable as well. Now, as we face future climate chaos, we may also face geological mayhem. n

provide a captivating lesson in diversity, and their explanations allow the reader a tantalising glimpse into the life of birds. As with any natural science text worth its salt, there’s some sex, too. Birkhead’s tales of the only bird that can reach orgasm – the red-billed buffalo weaver, if you’re interested – are a joy to read, simultaneously fascinating and hilarious. Such smut is the exception rather than the rule. But its inclusion demonstrates the broad-ranging content of Bird Sense, a book that is thoughtful, thoroughly researched and engagingly written throughout. n 18 February 2012 | NewScientist | 51