Thursday 29 July 2010

Welcome to the Anthropocene!

My first copy of the Open University's 'Geological Society Journal' hopped through the letter box a few days ago and one paper stood out from the others mainly because of it's authors. Dr Mark Williams and Dr Jan Zalasiewicz from Leicester University are two people I met at last years open day at the university and Jan is the author of a splendid book called 'Earth after Us' that I featured in a blog last year (click here to read). The title of the paper is "Enter the Anthropocene: an Epoch of time characterised by humans".

I've often speculated about the likely legacy we humans will leave for future occupiers of planet earth and whether there will be anything left worth occupying millions of years from now. I have always, perhaps a tad naively, believed that maybe man isn't quite as stupid as I fear and will drag the planet back 'from the brink' eventually. But will we? It seems that many believe the earth's failsafe feedback mechanisms could, quite soon be pushed beyond the point of no return, ultimately leading to the destruction of all life on planet earth, leaving nowt but a seemingly dead mass like Mars! James Lovelock, in his book 'Revenge of Gaia' I think touches on this very possibility if I remember correctly.

Anyway, Zalsiewicz and Wiliams' paper looks at the degree of environmental change brought about by man's activites, takes the idea first proposed by the Nobel Prize winning scientist Paul Crutzen and suggests ideas for formalising a specific epoch of geological time to cover the period of human influence on earth.

But how does one classify it? When did this epoch start? Is there a specific event that says before this event is the holocene and after it is the anthropocene? Well, there are a number of factors that might just leave a signature for future visiting geologists from afar to read. Firstly, the extinction of the large animals or 'megafauna' seemed to coincide with the rise of the human being, e.g the mammoths. However, it is difficult to be specific about the date as they died out in the americas 13,000 years ago, but died out 50,000 years ago in Australia. Some 'megafauna' survive today, e.g. elephants and rhino, but are unlikely to be around for too much longer. So maybe the Anthropocene requires a better means of classification?

The introduction of agriculture may provide a more specific date in order to gauge the start of this new epoch. WThe onset of agricultural practices brought widespread tree felling and planting of food crops which will have completely changed the composition of pollen grain accumulations in sediments worldwide, leaving a clear signature in the future rock record. This process will also have altered the level of carbon dioxide in the atmosphere and this too will be detectable by the future geologist.

Another potential means of dating the onset of the anthropocene could be in reading the signs of mans activities. No previous lifeform on earth has physically changed the outward structure of earth quite like man. Just how detectable the remains of man's handywork will be is difficult to gauge. Huge ancient cities vacated just a thousand years ago are now merely dust and rubble. But surely the vast quantities of brick, steel and concrete that make up our twenty-first century megacities will leave plenty of clues and a good idea of just when man was at his creative (or destructive, depending on your outlook) peak? As for how long the anthropocene will last is also difficult to estimate, but the pessimistic amongst us might suggest the width of this potential epoch might not occupy too much paper on the future geologist's stratigraphic column! 

The slightly depressing thing that came to my thoughts when reading this piece was that we humans and our relatives have only been around for a few hundred thousand years and are already making a good job of orchestrating our own demise. Yet the good ol' dinosaurs were the dominant vertebrate from the Triassic through to the end of the Cretaceous! That's a whopping 160 million years!?! That makes man's tenure seen pretty short term. And we like to think of ourselves as intelligent? Sorry, but making such a 'pig's ear' of everything in such a short (geologically speaking) space of time makes us look pretty dumb! That said, rapid increase followed by sudden extinction is not at all unusual. Let's hope we can turn things around before its too late.

Cheers for now!

Alyn.


Monday 12 July 2010

Blasphemy, blasphemy!

I am a regular follower of another geological blog called 'Geotripper' by a guy called Garry Hayes, a teacher of geology at Modesto Junior College in the USA and enjoy dipping into his prolific, enlightening and entertaining 'geoblogs'.

But a recent blog rather took me by surprise. Entitled "Ten Overrated Places to See Before You Die...Part Two" , imagine my shock on finding that the subject of this award, was Grand Canyon South Rim!!!

What? Are you mad? Before I comment further, take a look at his post here.

Grand Canyon at dawn from Bright Angel Lodges.
Overrated? I really don't think so!
(Photo by Alyn)


What Garry is referring to is 'the South Rim experience' and to a degree he is right. With around 277 miles of canyon to play with, tourist access is limited to only a few select places. As a visitor myself in 2008, I was surprised and I must say relieved to find that there is little in the way of development of Grand Canyon. As I understand it there are the lodges and apartments at Grand Canyon Village, a smaller development on the North Rim and also Phantom Ranch at the bottom of the canyon. Other than a few camp sites, that is about it and thank heavens for that say I. Can you imagine the horror of a multitude of 'Grand Canyon Skywalks' or similar crass developments littering this beautiful place?

So, Grand Canyon National Park saw fit to channel the tourist invasion into this one place. But is the whole South Rim experience spoiled as a result? Well, I can only relate my own experience. As a citizen of the UK, the trip over to Arizona constituted the 'trip of a lifetime' and yes, was on my list of those essential "places to visit before you die". What I wanted was a way for my family and my mother-in-law to stay as close to the Canyon as possible and at the very least get a feel for this wonderous place.

From L-R: Diane, Amy, Me, Ruth and Anna-Ruth outside our Bright Angel Lodge
(Photo by Alyn)


Well, we stayed in the magnificent Bright Angel Lodges, literally only yards from the Canyon edge.  And just a short walk away is the Bright Angel Restaurant where the most magnificent breakfast in the world awaits! One simply cannot 'overrate' their breakfast potatoes, sourdough toast and endless coffee, no Sir!
But I do understand where Garry is coming from. Sure, hoards of camcorder wielding folks hop off the bus in their droves, gaze over the canyon edge, pose for the obligatory photo with canyon backdrop, say "Gee, isn't it lovely" and then hop back on the bus and head for Vegas. For many, that is it. An afternoon's hop along the South Rim viewpoints,  a photo at each and prescious little else.



Evening bus tour of the South Rim viewpoints
(Photo by Alyn)

But for so many more, a visit to the South Rim of Grand Canyon is just the start of a whole lot more. As Gary points out, it is impossible to grasp the sheer magnitude of Grand Canyon just by standing at the edge and looking over. When you look at just the Kaibab Limestone layer for example and realise that this layer alone is about 300 feet thick, you may then get an appreciation of the scale a little. So I am left with a longing to revisit and take a hike through at least a part of it. One day my friends, one day . . . 

For countless others, they do just that. Hikes, canyon raft trips, camping etc, etc. So in my view, the Grand Canyon South Rim experience can serve as an introduction to the Grand Canyon. For some it is nothing but a single day out. But for many others though it can be a life changing experience and prove to be the start of something special, be it an appreciation of geology or even the feeling of being a little closer to God.

Overrated? Never!

Cheers for now!
Alyn.

Thursday 1 July 2010

Problem solved - I think!?!

Well, things seem to be working again!

As is often the way with I.T. the Blogger editor just seems to be workin again, though it was probably/possibly a 'cookie' issue or maybe some sort of conflict with a recently upgraded firewall and virus checker. At least they are two of the things I randomly tried and lo and behold, we're back on track! Hoorah!

So expect a proper blog in a day or two!

Back soon!

Cheers,
Alyn.