So you’re all asking about science, I get the hint!
Not my favourite topic (especially amongst friends), as you know, but, just
this once, I’ll try and tell you what I’m doing here. Or meant to be. For those
of you who haven’t already been put off by the title of this blog.
It’s actually been very humbling being here and seeing the degree of support
and infrastructure that is dedicated to Antarctic scientific research. There
are whole huge debates, I know, about whether Antarctica should be dedicated
to “peace and science” as it is or whether tourists, artists, musicians, adventurers
etc should be allowed more access. And I wouldn’t be arguing in support of the
scientists necessarily. Still, this is the way it is right now and I certainly
am glad to be working in the area that has enough clout in today’s world to
keep a military presence out of Antarctica and, for now, to be hindering the
exploitation of mineral resources here. Had this continent been dedicated to
“peace and the arts”, who knows, I may have studied drama after all.
So it’s really important to be doing ‘good’ science. The people who work here:
the chippies and sparkies and plumbers and steelies and chefs and genny-mechs
and vehicle folk… their jobs all exist in the name of science support (although
yes, I know, we’re ultimately here for political reasons). And although they
are all here for their own personal reasons, just as I am, they also need to
believe in the work that is happening here, just as I do.
Which is where I struggle since although I’m a scientist (or perhaps because
of it) I struggle with the moral high ground that science often pulls, not to
mention many of the very suspicious experiments that have been justified ‘in
the name of science’. I know, you’ll tell me about electricity and medicine
and bridges and vehicles and all these other things that have evolved through
scientific investigation and without which we wouldn’t do very well these days.
Plus I am a bit daunted by the idea that this ‘good science’ is being entrusted
into the hands of people like me. Those of you who know me may well also worry.
So how do I justify my science? It all goes back to climate change. Really.
For a long time ice cores have been used to try and gain some understanding
about past climates. If we know about past climates, then we might be better
able to predict future climates or, at the very least, appreciate whether recent
dramatic changes in the climate are likely due to man’s influence or merely
are part of a cycle that has ancient timescales.
Snow falls on the ground. It is light and fluffy and full of air. As more snow
falls, this earlier snow settles and becomes more compacted. With time, the
weight of snow above it becomes so heavy that it starts turning into ice. Any
air that is mixed in amongst the snow becomes trapped in bubbles in the ice.
Centuries later these bubbles become even more compacted and the ice is totally
translucent, ancient, a memory, like fossils and lake sediments, of days when
dinosaurs walked this planet. (A pilot was telling me just the other day over
tea about one place in Antarctica covered in whole fossilised dinosaurs.)
Unlike dinosaur fossils, the ice has a timescale, depth, which can be used
to understand not only what ancient climates were like but also how it has changed
with time. The ice is not just water, the trapped air is not nitrogen, oxygen,
carbon dioxide and argon. There are other chemicals and particles that might
suggest the presence of forests or deserts. More recent ice shows a record of
lead from petrol, and then it reducing again when unleaded fuel was introduced.
And around the time of industrialisation it looks like methane and carbon dioxide
concentrations soar. And so, it seems does the temperature of the planet. Obviously,
temperature can’t be measured directly from the ice..but the ratio of different
isotopes of oxygen trapped in air can tell you about temperature. It’s all proxy
data you see,– it’s all theories and assumptions but it does also seem
to be in agreement. And this is the basis of a sound scientific theory.
The problem is, we are making a massive assumption that once the snow falls
to the ground, all light and airy, the chemical compostion of the air doesn’t
change. It just gets pushed deeper and deeper and eventually trapped in bubbles
in ice until thousands of years later some random scientist drills a very deep
hole, takes a slice of ice and analyses the air that is trapped within it.
It’s a fairly sound argument once the air is trapped. However, you and I know
full well that no small layer of snow is going to stop air from diffusing upwards
and downwards and, quite frankly, wherever it’s warmer (if it’s cold) or colder
(if it’s warm). And on its travels it might pick up molecules from the clouds
and deliver them to the snow or molecules in the snow and free them into the
open atmosphere. It’s all physics. And chemistry. Maybe maths. It doesn’t really
matter what it is, it doesn’t care even if we do. I’m no glaciologist as you
know so the above story is a massive simplification. And I’m not patronising
you,– I really know little more than this (but I’m learning).
What I do know is that to truly understand the record of molecules trapped
in air deep, deep down in the ice, we need to understand what happens to air,
and more importantly, the various molecules in it, between the surface and the
trapped bubbles. Which is why I’ve been employed as an atmospheric chemist.
And why I’m drilling holes (to probe chemistry in the snow) and flying blimps
(to probe chemistry in the air). Oh yeah, and why, next year, we’ll be firing
a laser out of the east window of the CASLab,- the one with the stunning view.
That’s to monitor absorption of light from different molecules in the air. Not
as star-trek as earlier blog-readers might hope but still pretty cool. I was
peering out that window just the other day when I’m sure I saw a morris minor
kite contraption heading off to the pole….
More details on that stuff, if you’re interested, anon… hope you’re all well,
and thanks for keepiong the emails/blogs aflowing.