Geology for Global Development

Geology for Global Development

The Case Against Fieldwork – How can we internalise the carbon cost of fieldwork, as scientists who investigate the earth system?

Contrails from a jetliner. Image courtesy Pixabay/diddi4

There are few, if any, fields of human study for which fieldwork is more fundamental than geology. For many geologists, the solid earth itself is their subject, and this means observations can be made at any given location on the planet. Moreover, the local quirks of different environments almost necessitate a diverse range of study sites for us to fully comprehend the differing processes that govern the world we see around us.

Beyond offering us the chance to make observations in a variety of different locations, fieldwork allows us to test our laboratory models, to interact with researchers from other institutions, and from a personal standpoint can broaden perspectives while exploring and experiencing new places. These positive consequences of exploration and observation are offset by the impact that researchers have on their chosen field sites. ‘Leave only footprints, take only photos’ is a fine motto, but much like Schrödinger’s cat of quantum physics, when we choose to observe the natural system, we have an impact on the subject of our observation.

The scale of that impact can vary widely. When I undertook fieldwork in New Zealand, in field areas culturally significant to the Maori people, we took great pains to limit any long lasting effect on the landscape (with help from the NZ Department of Conservation), taking only small quantities of water samples and keeping to specific areas. The vast majority of field scientists recognise that their own presence can be a source of systematic bias, and experimental or observational design to limit that bias is undoubtedly essential. There’s one big impact that we rarely consider, though; the carbon footprint of travel to and from far-flung locations. Even if the effect of emissions from a single trip is relatively minor, the cumulative effect of climate change systematically influences a great many geological processes.

The carbon footprint of an individual is not always an easy number to pin down. Given that nearly every action we take has some impact on emissions, there are a huge number of variables to constrain for any single person. With some caveats, it’s easier to use data for large populations and average to an individual level. The World Bank provides nation-level data for CO2 emissions per capita, which is highly informative. Unsurprisingly, emissions from Western Europe are higher than the so-called developing world (approx 6.4 tons of CO2 per person per year in W Europe, and 0.8 tons in sub-Saharan Africa for example), while the US values are higher still (16.5 tons).

How do these numbers compare with the emissions from flying? Again, it is difficult to nail down an exact value for airline pollution, with estimates complicated by a variety of aircraft of differing efficiencies in service, as well as non-linear emissions with respect to the length of a journey (taking off burns more fuel, meaning shorter flights have a higher proportional impact – read more here). Roughly, though, airliners emit between 100-260g of CO2 per passenger kilometre. Scaling up, this means a return trans-Atlantic flight puts around a ton of CO2 into the atmosphere per passenger; thus, fieldwork across the world could rapidly make a huge impact on the overall carbon output of an individual.

My own experience is illustrative. As a PhD student in Germany, I felt very fortunate to carry out fieldwork in both Taiwan (c. 9000km from Berlin) and New Zealand (c. 18000km from Berlin); the high rates of erosion in the mountains in those settings made them the ideal location to study landslides and related chemical weathering. However, comparing my emissions from flying over the course of a 4-year PhD purely for fieldwork (probably at least 10-12 tons) with the average emissions per person in Germany (around 8-10 tons of CO2 annually) makes for uncomfortable reading. Not only was this worth more than a whole years’ worth for the average German citizen, but it was far in excess of a level that would, if adopted by everyone, help mitigate dangerous climate change. While it is still under debate what the acceptable level of emissions per person would be, my personal emissions are certainly incompatible with any of the proposed levels, which are often cited as closer to 2 tons per year each.

This would even be true if I had made every other lifestyle change that is often discussed to reduce one’s own ecological impact; a vegan diet, using only public transport, and limiting purchases of new goods; these would not have sufficiently offset the emissions just from fieldwork.

More and more scientists are already reckoning with these moral questions in regards to conferences. A recent editorial about the amount of emissions from the American Geophysical Union’s Fall meeting highlighted that scientists gathered together from across the world have a non-negligible impact on CO2. Such large conferences also present a problem of ‘optics’ as the media might describe it; how are scientists supposed to advocate for a lower carbon economic system when their massed meeting could create such potential harm? Perhaps fieldwork has a less obvious optics problem, given that geologists are scattered around the world, but there remains potential for accusations of hypocrisy to be made.

I’m certainly not the first to be concerned about these issues. When I’ve discussed them before with friends and colleagues, a kind of compromise is often the solution that has been suggested to me: weigh up the costs and benefits of the fieldwork. Perhaps the work in question is directly relevant for carbon capture research, or modelling of the climatic system; in this case, the direct impact of the research resulting from the fieldwork might be more tangible, and in some cases even quantifiable.

For a great many geologists who don’t work on the climate system, these direct comparisons are not possible. In this case, we are forced to make subjective value judgements about how the positive outcomes of our research and findings should be compared with the incremental changes that result in the environmental system from our emissions. These judgements are certainly not unique to geologists, but are perhaps more stark than others given the potential for dramatic climate change to fundamentally alter many surface or marine environments that have been the subject of centuries of geological observation.

I certainly would not presume to make these value judgements for other scientists. We each have our own perspectives, and these may often be highly personal decisions. Moreover, I wouldn’t expect geologists to give up fieldwork lightly, or even at all; it’s so crucial to the science as we know it, and is often the highlight of many researchers calendars.

I would argue, though, that the time has come for us to seriously question whether we can do fieldwork in a more sustainable fashion. We’re often seeking the prime location to test our hypotheses, which may be half way around the world, but instead of forgoing these field sites, we should perhaps ask ourselves: could local researchers take the samples we require on our behalf? There’s an added bonus to this suggestion, too – it could encourage productive collaboration across borders, as well as helping development in economically deprived-but-geologically-interesting countries through the intersection of ideas.

Whether it’s seeking new collaborators in the ‘perfect setting’, or seeking a compromise field-site closer to home, or even to embrace a slower way of travelling (such as trains) there are ways to reduce flight for fieldwork. As earth scientists, we are among the most informed citizens about the potential for catastrophic climate change. It is up to each scientist to decide for themselves whether this knowledge carries with it an imperative to act, but given the global consequences of our actions such an imperative seems more urgent than ever.

Robert Emberson is a science writer, currently based in Vancouver, Canada. He can be contacted via Twitter (@RobertEmberson) or via his website (www.robertemberson.com).

Peat in the Tropics

As has been previously discussed in Robert’s blog, fertile soil is an incredibly important resource that is fast running out in many regions of the world. It is true that soil’s importance for agriculture (and sustainable development) cannot be understated, but I wish to focus on another aspect of soil in this week’s blog– its ability to store carbon.

One soil type in particular, peat, is an incredibly important form of carbon storage. Despite only covering 3% of the Earth’s land surface it contains a third of the carbon stored in soils, formed by the build-up of partially decomposed organic carbon, trapped in waterlogged and anoxic conditions. For this reason the preservation of peatland is of the upmost importance, and should be considered in sustainable development efforts in order to prevent the release of vast amounts of carbon into the atmosphere.

Figure 1- Distribution of mires around the world. Source: International Peat Society, Available www.peatsociety.fi

When you picture peat it is typically in a cool and damp climate, such as in the highlands of Scotland or expanses of tundra within the Arctic Circle. This is because the cooler climates further impede the decomposition of organic matter and facilitate the formation of peaty soils. Recently, however, it has been discovered that peat forms in other regions too, and in quantities far vaster than had ever been considered before. These tropical peat deposits form in the swamps commonly found in the river basins of warm and humid regions. Although warm and wet conditions typically aid the processes of rot and decay, the often stagnant water of swamps produces anoxic environments not dissimilar to those in the extensive peatlands found at higher latitudes. Conditions are exacerbated by poor drainage, high rainfall and overbank flooding by rivers, meaning that the land never truly gets the opportunity to dry out and peatlands are able to form, albeit in much smaller expanses than those in the North.

Despite the smaller size of tropical peat deposits they are disproportionately more significant to sustainable development, as they tend to be focussed in regions where development is occurring rapidly – central Africa, South East Asia and South America. Building on and draining these fragile ecosystems could result in mass release of carbon dioxide.

An example of a tropical peat deposit is the Cuvette Centrale depression in the Central Congo basin, where the peat is relatively shallow (with a median depth of 2m), but has a large aerial extent, making it the greatest ranging peatland in the tropics. Other extensive peat deposits can be found in the amazon rainforest and in tropical Asia (for example the island of Borneo) but land use changes in recent years have drastically reduced the amount of peatland in SE Asia, as much has been drained for agricultural use. It is predicted that SE Asian peatland will be lost completely by 2030, but thankfully the peatlands in other areas of the world are in a significantly more pristine condition, relatively unaffected by humans due to their relative inaccessibility.

Drainage of land for agricultural use is not the only threat to tropical peatlands. Climate change is acting to reduce the annual precipitation in many tropical regions, meaning carbon trapped in peat is oxidised more readily and able to decompose. Even though tropical peatlands are only a fraction of the size of their northern, cooler cousins, they still represent huge carbon stores that, if destroyed, could accelerate the release of carbon into the atmosphere and accelerate global warming further, entering into a feedback loop which will release tonnes of carbon into the atmosphere that has lain trapped underground for millennia. Carbon stocks of peat in the Cuvette Centrale alone are potentially equal to 20 years of current fossil fuel emissions from the USA, demonstrating the importance of protecting this seemingly insignificant soil type.

Figure 3 – SE Asian rainforest. It is in rainforests such as this that peatlands are quickly being drained for agricultural use. Source: https://imaggeo.egu.eu/view/4268/

A further concern is that swamplands are a refuge for many of the world’s remaining megafaunal populations, including lowland gorillas and forest elephants. It is clear that if Africa and South American peatlands are to avoid the fate of the SE Asian counterparts, they must become a conservation research priority.  Doing this would undoubtedly help to combat the rise of CO2 levels and simultaneously work towards the UN Sustainable Development Goal 13 – climate action.

Bárbara Zambelli Azevedo: Phosphorus Crisis – A Food Crisis?

Take a look and try to identify anything around you that has phosphorus as a component.

Phosphorus – the P element – is critical for life, like oxygen, nitrogen and carbon, being present in every plant, animal and bacteria. It constitutes cell walls, DNA, RNA and ATP, which transports energy to the brain. Our bones and teeth include phosphorus.

Now look again and you might see that phosphorus is more present in your daily life than you first imagined.

We obtain our phosphorus by eating plant- and animal-based food. Cattle obtain their phosphorus from feed, grazing and supplements. On the other hand, plants obtain phosphorus from the soil by their roots, transporting, absorbing and storing it to where it is needed. If a plant doesn’t get enough P, their growth is strongly affected, the formation of fruits and seeds decreases and crops yield less.

Image 1: Coffee crops in Minas Gerais, Brazil (photo: Bárbara Zambelli)

Image 2: Banana crops in Gran Canária, Spain (photo Bárbara Zambelli)

The phosphorus (P) present in soils is either natural or added by the use of fertilisers, manure and organic residues. Natural P exists on soils as a result of phosphatic bedrock weathering. As a geological feature, it is not evely distributed on the Earth’s surface and it can take a long time to form, such as a million years.

Why should we worry about phosphorus?

Phosphorus is a non-renewable resource that cannot be replaced or synthesized for plant nutrition. Moreover, it is one of the most reactive nutrients in the soil, being easily transformed into forms that are unavailable to plants. A study shows that about 90% of all the phosphorus mined worldwide is used for food production. According to USGS, 88% of all reserves are under control of 5 countries: Morocco, China, Algeria, Syria and South Africa. Morocco is by far the country with the largest reserve, holding 74% of the world’s phosphate reserves. Therefore, most of the countries rely on phosphorus imports to sustain agriculture. The scarcity scenario is not only physical but also geopolitical, economical and managerial.

Image 3: phosphorus mine (photo: Alexandra Pugachevsky, source)

The world’s population is growing steadily, projected to reach 9.7 billion people by 2050. In this sense, feeding almost 2 billion new mouths by 2050 is an increasing challenge. Growing food demand equals growing phosphorus demand.

The reserves of phosphorus will be depleted sooner or later. Some authors argue that the ‘phosphorus peak’ will happen pretty soon, in 2030, while others says that it won’t happen before 2100. There is no consensus because different studies are based on different methodologies and assumptions about demand and uncertainties about supply.

In this manner, to achieve SDG 2 and assure that everyone has access to safe and affordable food until 2030, we must change the way we use, source and distribute phosphorus among the global food production.

Another important issue is the biofuels production. With an increasing pressure to reduce oil consumption and greenhouse gases emissions, accordingly to the Paris Agreement on COP21, many countries are turning to biofuels, such as alcohol made from maize or sugarcane. These crops also needs phosphorus and use land that could be used for agricultural purposes.

What about the environment?

While phosphorus is a scarce resource vital for agriculture, it is also a pollutant of waterbodies. Not all phosphorus used as fertiliser is absorbed by plants. Some phosphorus stays on the soil and is later carried to streams, rivers and lakes. This anthropogenic input of phosphorus generates an anomalous concentration of P nutrient in water bodies, encouraging the growth of blue and green algal and causing algal blooms. The increase of nutrients and then algae and higher plants is called eutrophication.

Eutrophication can be toxic or deeply change the ecology of the waterbody. It produces many undesirable effects regarding human society, such as drinking water problems, decrease of seafood production and presence of toxins in drinking water and seafood.

Image 4: eutrophication at a wastewater outlet in Potomac River, Washngton D.C. (photo: Alexandr Trubetskoy, source)

Another environmental problem concerns mining tailings. Phosphatic rocks, as a result of its chemical composition, may contain notable amounts of naturally occurring radioactive materials. The process of converting the phosphorus ore to phosphoric acid (that can be used as fertiliser) or elemental phosphorus produces phosphogypsum as a primary waste by-product. These processes concentrate in the waste most of the naturally occurring thorium and uranium and its decay products, such as radium and radon. If proper attention is not given to this waste, it risks contaminating the air with radon gas (radioactive), and groundwater, affecting farmers and the wider population.

What can we do?

We have to think in ways to reduce the consumption, reuse and recycle.

A simple way for reduce phosphorus consumption is actually not a brand new idea. The answer relies on the symbiotic association between a small fungus and plants’ roots called ‘mycorrhizal’. The symbiose, which is a win-win relation, occurs when the fungus bounds to the roots. This fungus grows faster and it is more efficient on searching for phosphorus than the plants’ roots. So it provides phosphorus that were on the soil but could not be absorbed by the plant and, in return the plant nourishes it. Therefore, by using mycorrhizal association it possible to reduce the amount of phosphorus fertilisers needs of a crop, by enhancing its P absorption by the plant. In this video, Dr Mohamed Hijri explore use of mycorrhiza to optimise phosphorus use for agricultural purposes. Another way of reducing consumption would be encouraging diets that has fewer aliments that are phosphorus intenses, like meat and dairy products.

About reuse, we can think on reducing losses on the food chain, rubbish bin and animal manure, for example. Those are all sources of phosphate that cannot be overseen.

Concerning recycling, it is important to highlight the safe use of wastewater for agricultural purposes. The UN-Water has a project on this issue can be downloaded here. Its usage is already bigger than expected! Almost 100% the phosphorus eaten in food is excreted. The sewage treatment as a way to recover phosphorus present in human screta for agriculture, although controversial, is already being done in Sweden for example. Since the population is growing and a big part of it will settle down in peri-urban areas in mega-cities in the next few years, a big attention must be given to these places. They are becoming a ‘hotspot’ for phosphate production.

To know more about the phosphorus crisis and opportunities click here, here and here.

How do you monitor an internationally disruptive volcanic eruption? How can you communicate SDGs in an Earth Science class? Jesse Zondervan’s Nov 13 – Dec 13 2017 #GfGDpicks #SciComm

Each month, Jesse Zondervan picks his favourite posts from geoscience and development blogs/news, relevant to the work and interests of  Geology for Global Development . Here’s a round-up of Jesse’s selections for the past four weeks:

Bali’s Mount Angung started erupting ash this month, and a post on the Pacific Disaster Center’s website gives you an insight into the workings of Indonesia’s early warning and decision support system. How do you monitor an internationally disruptive volcanic eruption?

In Japan, eruptions in 2016 were preceded by large earthquakes (MW 7.0). A team of researchers used Japan’s high resolution seismic network to investigate the underground effects of earthquakes and volcanoes. How does an earthquake affect a volcano’s activity?

Next to plenty of disaster risk stories – including the simple question: why can’t we predict earthquakes? -, this month brings you a computer simulation tool to predict flood hazards on coral-reef-lined coasts and some thoughts on how to communicate SDGs in an earth science classroom.

Have a look!

Education/communication

The UN Sustainable Development Goals – what they are, why they exist by Laura Guertin at AGU’s GeoEd Trek blog

GeoTalk: How an EGU Public Engagement Grant contributed to video lessons on earthquake education by Laura Roberts-Artla at the EGU’s GeoTalk blog

Credit: Michael W. Ishak, used under CC BY-SA 4.0 license

Disaster Risk

Disaster Geology: 2017’s Most Deadly Earthquake by Dana Hunter at Scientific American

Can the rubble of history help shape today’s resilient cities? By David Sislen at Sustainable Cities

The underground effects of earthquakes and volcanoes at phys.org

Why Can’t We Predict Earthquakes? By David Bressan at Forbes

Detecting landslide precursors from space by Dave Petley at the AGU Landslide Blog

Ocean Sediments Off Pacific Coast May Feed Tsunami Danger by Kevin Krajick at State of the Planet

Life-saving technology provides alert as Bali’s Mount Agung spews ash, raises alarm at Pacific Disaster Center

Climate Change Adaptation

Scientists counter threat of flooding on coral reef coasts by Olivia Trani at AGU’s GeoSpace blog

Check back next month for more picks!

Follow Jesse Zondervan @JesseZondervan. Follow us @Geo_Dev & Facebook.