So what is it you do?

Physical geography. It encompasses a lot of things, and its engagement with many modern problems like how to reduce flood risk is arguably one of the reasons why it is enjoying a resurgence in popularity. An article in The Guardian went some way to explain this new-found popularity, emphasising how important it is in today’s world and the benefits graduates with a geography degree have in the job market – i.e. they are highly employable. What interests me, and has for some time – especially since starting my Ph.D. – are some of the facets of physical geography that are overlooked.

We all know the typical (and believe me very clichéd) stereotypes about physical geographers:

“All you do is colour in maps!”

“You’re not doing a proper science.”

The former being something I have capitalised on for my twitter name; a little in-joke that amuses me more than it should and provides no amusement whatsoever for anyone else. But that is beside the point. Those with a little more knowledge are aware that physical geography encompasses the study of rivers, glaciers, deserts and all manner of other landforms. What I think is less known is that physical geography also houses an increasingly important subtopic: that of Quaternary science.

It would be no surprise to me if a blank look suddenly appeared. Why wouldn’t it? I didn’t even know about Quaternary science until I began my degree a few years ago. It is that which got me thinking about why people don’t know what Quaternary science is. More importantly, it got me thinking why should anyone care about it. To that end has come this attempt to remove the shroud of mystery from Quaternary science, and to hopefully explain why I think it is so important.

Where to start? Perhaps it is best that I start with the definition of Quaternary Science: it being the study of climatic and environmental change over the last geological period covering 2.58 million years. In the grand scheme of our planet it is but a snapshot of time, but it is a very important snapshot. During this time we, Homo sapiens, for better or worse evolved to make our mark on this planet. Over this time there have been many ice ages and warm periods through which our species and ancestors have survived. But how do we know that? How do we have any idea what changes our planet has been through when people aren’t around to measure or write down what’s happened? Why is understanding this important for our future?

It is here that you’ll have to indulge me. Quaternary scientists can be thought of as detectives, making us an environmental Sherlock Holmes and Earth’s climatic and environmental history as Moriarty. By no means am I implying that Earth is evil and has a self-involved agenda, but merely saying that it’s past environmental and climatic history keeps itself hidden. It’s not until us wannabe Sherlock Holmes’ find clues with the tools that we have at our disposal that we understand what went on.

These clues can be found in a multitude of places. Lakes; peatbogs; oceans; ice sheets; deserts; cliff faces; even the landscape itself can provide you with indicators as to what our planet’s climatic and environmental history was like if you know how to look. What’s more is that getting hold of these clues is really one of the most exciting things us Quaternary scientists get to do. They allow us to be let loose from our desks and out into the field: be this a lake in a far-flung island or out onto the Antarctic ice sheet.

The next question is how do you interpret these clues once you have them? A blood stain at a crime scene means little until you obtain the DNA that determines whom it belongs to. Like this, these environmental clues are worthless without a way to interpret them. In criminal investigations detectives can have direct evidence to identify the criminal such as CCTV. Unfortunately a Quaternary scientist does not have such evidence and we have to employ a middleman. In the business this middleman is termed a proxy, and there are a multitude of them. You can use pollen, single-celled algae, chemicals produced by living organisms, even ancient DNA preserved for thousands of years – to name a few. We never use just one of these bits of evidence on its own to piece together what happened in the Earth’s past – much like a criminal investigation doesn’t rely on one single piece of evidence to charge someone. We link these different lines of evidence to what we see at the present so that we can understand how our planet is working and expressing itself, allowing us to be confident that we are interpreting our evidence correctly. Only then do we piece together all the difference lines of evidence to disentangle the complex, and occasionally infuriating, mysteries of our planet’s past climate and environment. It is there that the strength of Quaternary science really lies: you don’t use one piece of evidence, you use many.

In all of this though the question still remains: why does it matter? Why should you care about someone looking at something that doesn’t directly relate to you in the here and now? With COP21 currently going on this is a particularly pertinent point because it does relate to you. Quaternary science can be thought of like your life experiences. Your life story helps you figure out what you should or shouldn’t do, informing every future decision you make. With more memories you become wiser and make better decisions for your future. Quaternary science is a human’s way of understanding Earth’s latest life story, and makes us the voice to a key part of our planet’s history that is otherwise mute. Being Earth’s ‘interpreters’ makes us a vital player in understanding and combating future global warming. Without Quaternary science we have no idea as to how the past climate changed; what the Earth’s natural variability is before humans starting affecting the planet. We are the ones who can tell you how the Earth could respond to the actions of man based on how it has responded in the past. Our role is not restricted to saying what will happen with more carbon dioxide. We can provide insight into whether ecosystems that we rely on for water or food have gone past a point of no return. Whether a landscape is going to stay as we want it to be or change irreversibly. It allows us to figure out whether the climate or environment motivated our ancestors to migrate and expand. Quaternary science is absolutely vital for understanding our planet, and Quaternary scientists are integral to being a voice that would otherwise go unheard. Simply: without Quaternary science we are lost in understanding our future.

Perhaps all this is best summarised with a quote that I heard in one of the first lectures I had about Quaternary science. It is by Charles Lyell  – one of the founding fathers of Quaternary science – and has resonance across more than just this field of study.

“The present is the key to the past, but the past is the key to the future.”

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There And Back Again: Returning To The South Pacific

Last year I was told that my fieldwork in Samoa and New Caledonia was the best I’d ever experience; turns out that was a lie. This year I was fortunate enough to return to Samoa, and even more fortunate to go to the small island of Atiu in the Cook Islands. There was one very simple reason for me, along with Prof. David Sear and Dr Pete Langdon, to return to the South Pacific: we needed more sediment from the lakes on these islands. This sediment is crucial to determine how a massive band of rain – called the South Pacific Convergence Zone (SPCZ) – has moved in the past. Millions of people are dependent on the SPCZ for drinking water. Data from satellites has shown that various climatic phenomena that operate in the Pacific Ocean cause the South Pacific Convergence Zone to move. With future climate change likely to strongly affect the SPCZ and cause it to move, it is vital that we understand how it has moved in the past so that we can predict how it will move in the future.

We left London Heathrow for a somewhat gruelling 30-hour transit to Atiu to take cores from Lake Teroto. Shortly after arriving we began work obtaining wood from the local coffin maker to make our coring platform. We needed this to not only support us but to hold aluminium casing which we would be sending the corer down. It was at this point that we discovered the value of our helper Koro – a truly remarkable man. Koro is one of an increasing number of Polynesians who is navigating the Pacific on double-hulled canoes using the stars as his guide just like his ancestors did. He helped us create our coring platform; had an intuitive knowledge of what we needed help with before even asking; and climbed up coconut trees to get us fresh coconuts to drink from when working under the tropical sun. With his help we managed to obtain eight metres of sediment from the bottom of the lake: more than enough for me to work on over the remainder of my Ph.D.! What was even more exciting than the amount of mud we obtained was that we found some of it had distinct layers. This is really intriguing as layers such as those could indicate that sediment was being deposited at specific times of the year, allowing us to look at annual changes in the Lake Teroto record.

Following our week in Atiu we went on to Samoa to collect samples from Lake Lanoto’o. Having been to this lake last year we were well prepared for what was in store: red mud that got absolutely everywhere, and leeches that had a remarkable knack for getting in unusual places. It was in Samoa that we were joined by Georgia Eves – an undergraduate student who will be working on the samples obtained here for her dissertation. Georgia did a fantastic job, getting her first chance at using a corer and obtaining sediment from this fascinating lake. We managed to obtain three metres of sediment from the lake – the most that has been taken to date! Following this success we immersed ourselves in Samoan culture, visiting the local flea market for souveniers – a coconut bra or two may have been purchased… We spent our final night in a beach fale, this being a hut on a beach, and watching Samoan firedancing: a truly spectacular sight.

At times gruelling, yet always enjoyable, this fieldwork expedition was not only our most successful but definitely the most enjoyable. Here’s to hoping we can return to the South Pacific again soon.

Lake coring in the South Seas

Bleary eyed I walked off a plane onto Samoan soil just ahead of two of my supervisors, Prof. David Sear and Dr. Pete Langdon. It was around 6am and the first thing that hit me was a wall of humidity and the surprising lack of flies. Traversing through the airport we were welcomed by Samoans singing and playing guitars, immediately highlighting that I was in a very different place to anywhere I have been before. After David got the keys for the rental car, we drove along the coastline as the sun broke the horizon. Passing the local homesteads called Fales, we entered Apia (Samoa’s capital)and then took the main road that cut across the country. With the Sun blazing in the sky we came across our first magnificent natural wonder: a waterfall cascading into a deep ravine.

We then met Josie: our guide. She was incredibly friendly and welcoming, introducing us to the ‘boys’ who would help us over the next few days. With the assistance of Lucy and Anushka, Josie served us with a much needed breakfast on a veranda overlooking the picturesque Samoan coastline.

Beginning a little later than expected due to the never-ending rain we set off on a hike to the lake. We hiked through an overgrown grassy track, entering the jungle proper after overcoming obstacles akin to a Total Wipeout slalom. Needless to say that the boys – being ridiculously fit like most Samoans – charged off to the lake with our kit. Bright red flowers lined the track; trees soared into the sky; a bright orange mud lay beneath my feet that managed to get on virtually all of my clothes. For nearly two hours Pete, David and I hiked with Josie to the lake, finally gaining a view after fighting our way through dense vegetation. Simply, the first view of the lake was magnificent. Hidden away inside the crater of an extinct volcano all you could see was this near-perfect circle of green water. After gawking for a bit and appreciating where we were we began the work.

This started off with assembling a raft from various materials – a key component being tire inner tubes. Admittedly there were a few minor hiccups along the way: one being that an inflatable boat we had hoped to use had various holes in. The boys really proved their worth making the raft; never complaining, they really helped make what could have been an arduous task fun. Once the raft was built Pete and I rowed out, taking measurements of the lake’s depth so that we could gain an understanding of the lake’s bathymetry and determine where the deepest point was for coring the following day.

It wasn’t until the following day that we really got down to what we had come to Samoa to do: obtain lake sediment cores from Lake Lanoto’o. David, Pete and I rowed to the deepest part of the lake with all the kit – no easy task! – and worked as a team to obtain as long a core as we possibly could. After doing all of the necessary tasks to get our first core, we carefully brought up the corer to the surface. With trepidation, and much excitement, the core was extruded from the corer – we had mud! We repeated this process a few more times, eventually getting just under two metres of sediment. Sadly more couldn’t be obtained as several of the coring rods broke. I spent the following day cleaning the cores and logging their stratigraphy, taking samples at one centimetre intervals after I had done this. You would be surprised at how long it takes to do this – an entire day!

It wasn’t all work, though. On our final day in Samoa we visited Samoa’s version of a duck pond: a turtle pond. One of the most surreal moments of the trip was standing by the edge of this pond feeding the turtles a loaf of bread bought from a nearby store. I also went snorkling for the first time. Swimming along Samoa’s coral reef, admittedly fighting against a pretty strong current, I witnessed all sorts of weird and wonderful fish. The real highlight of the day, though, had to be the dinner Josie, Anushka and Lucy prepared for us on our final night. Cooked in a traditional Samoan stone oven, tuna caught that morning was wrapped in banana leaves and slow cooked. I’ve honestly never tasted better tuna in my life. We were also served taro, a vegetable that is a Samoan staple, as part of the meal. If you’re ever in need of being filled up with as little food as possible then taro is your answer.

David and Pete continually said to me that it’ll probably be the best fieldwork I will ever experience; I think that I have to agree.