Science Week 2017: understanding climate change

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This blog was written by Giulia Magnarini, Birkbeck graduate in Planetary Sciences with Astronomy and PhD candidate in Earth Sciences at UCL.scienceweekclimatechange850x450‘To understand current climate changes, we need to understand past events. However, using our existing climate model is really difficult.’ This is how Professor Andrew Carter began his talk on Earth’s long-term climate. Professor Carter’s research focuses on studying Antarctica in terms of climate changes.

Despite some persistent denial, evidence for an increasingly warm climate is clear. To provide a visual idea of the impact that the total melt of ice in Antarctica could have, Professor Carter asked the audience to imagine Big Ben under water up to the clock. Thames barriers would be ineffective and it is increasingly obvious how important research on climate change to tackle its consequential threats is.

Geological evidence for the first appearance of the ice sheet in Antarctica resides in sediments that date from 33 million years ago. The question is: why did Antarctica freeze over? Two hypotheses are proposed. The first one involved plate tectonics; as Antarctica separated from Australia and South America (circa 50 million years ago), ocean circulation changed and the strong Antarctic Circumpolar Current emerged, causing thermal isolation of the continent.

The second one takes reduction of atmospheric carbon dioxide into account. Historic data collected for ice volume, deep sea temperature and sea level all follow the same trend of the reconstructed amount of carbon dioxide in the atmosphere.

However, there are problems with both hypotheses. For instance, at the moment of the break, Antarctica was in a northern position and, although carbon dioxide was lower, overall temperature was warmer.

There are many difficulties in modelling over geological time. Nowadays, different models running for Antarctica show completely different results. Improving the quality of data is crucial because uncertainties are very high. On this point, Professor Carter has been conducting what is called ‘provenance analysis.’ This involves studying sand grains to locate their sources to better constrain past tectonic events and past environmental conditions. The grains that Professor Carter studies have typical shape due to ice erosion. Detrital zircons (very resistant minerals) are used to conduct U-Pb geochronological assessments to reconstruct the age distribution of the sediments. These ages are then compared with rocks from different areas for which age is known.

Oceanic drilling programs have been conducted within the ‘Iceberg Alley’. This is an area where icebergs are transported by currents and during the journey they deposit sediments. Results from sediment cores have shown that the grains come from other areas, meaning that they had been transported by icebergs, therefore implying that ice was already present on the continent at that time.

This new set of information can help improving tectonic models related to the opening of oceanic passages. Sampling the ‘Shag Rocks’, which are the only exposed part of the continental block within the Iceberg Alley, would be of benefit for this. Unfortunately, due to strong currents, this can be very difficult and dangerous.

Professor Carter concluded by pointing out the importance of better understanding the geology of this area because it was here that the Antarctic Circumpolar Current originated. This in turn had a significant implication on the global cooling of the planet. In fact, its influence reaches up to the northern hemisphere.

Therefore, more geological data can greatly improve the quality of climatic models. Better and more reliable climatic models will be fundamental to help future governments make important decisions.

Science Week 2017: geoengineering, climate change and evolution

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This blog was written by Giulia Magnarini, Birkbeck graduate in Planetary Sciences with Astronomy and PhD candidate in Earth Sciences at UCL.geoengineeringmethods-climatecentral1-2To our knowledge, Earth is the only planet where life has developed. Life appeared very soon after the formation of our planet about 4.5 billion years ago, and continues to survive.

Dr. Philippe Pogge Von Strandmann examined the mechanisms that keep the Earth habitable in a recent talk. He noted that despite large oscillations between cold periods (ice ages) and warmer intervals (interglacial stages), our planet has managed to avoid the fates of Mars and Venus. Both of these planets have lost their oceans, while Earth has retained liquid water at its surface.

Meteorite impacts, glaciations and volcanic eruptions are some of the processes that mark the very dynamic history of the Earth. Atmospheric composition has also changed dramatically over time, formerly being composed of mainly CO2, to the increase of nitrogen and oxygen. These events across Earth’s history have caused extinction of some species, but life has survived nevertheless, and continues to adapt and evolve.

Dr. Von Strandmann illustrated some of the theories that aim to explain the endurance of life on our planet – for instance, Gaia Theory, the Medea Hypothesis, the Daisyworld Experiment – and explored the influence of geological processes on climate mitigation. Carbon dioxide, a greenhouse gas, dictates atmospheric and surface temperature; therefore its atmospheric abundance is critical in long-term climate change. Plate tectonics play an important role by removing gases through subduction (where oceanic plates sink under continental plates) and re-emitting them through eruptions. But this process is slow, acting on a time scale of hundreds of millions of years. The weathering of rocks is a more effective process. Dissolved material is washed away by rivers into oceans to form rocks, which lock crucial amounts of carbon dioxide inside.

Dr. Von Strandmann concluded his talk with considerations about consequences of human actions in the face of the current climatic stage. Atmospheric CO2 has surpassed the barrier of 400 ppm (parts per million) and over the last decade, every year has been hotter than the one prior. This is evidence we can neither deny nor ignore. Climate change is going to exert challenging environmental pressures, for instance in a reduction of land available for agriculture. Geoengineers are committed to finding ways to actively remove carbon dioxide from the atmosphere. However, the effects of carbon sequestration are still unknown and more research is needed.scienceweekgeoengineeringoriginalThe second speaker, PhD candidate Tianchen Hen, illustrated the emergence of animals that occurred as oxygen levels began to rise. About 540 million years ago, the Cambrian fauna started diversifying from the Ediacaran fauna, introducing several biological innovations. This event is known as the ‘Cambrian Explosion’, and is characterised by an accelerated rate of diversification. Cambrian rocks preserve amazing fossil records, dominated by Trilobites – the first representation of animals that we can call our ancestors.

What seems to be a sudden change in the fossil record has caused significant debate. Charles Darwin noted it to be the main counter-argument to his evolutionary theory of natural selection. However, although all Ediacaran fauna became extinct and were replaced by Cambrian fauna, there is not a distinct separation. Both faunae share a certain degree of diversification and show symmetrical structures. Indeed, molecular biology suggests that a co-occurrence is rooted in the Ediacaran fauna.

The rise of oxygen levels is vital for animal metabolism. It influences body size and allows more intense activities. However, it is unlikely that just one mechanism can explain the triggering of early animal radiation. Tianchen Hen explained other possible factors that may have contributed. Hox genes are responsible for biological innovations, such as appearance of limbs and eyes that could induce behavioural changes. These changes may have refined the relationship between predators and prey, bringing diversification in the battle to survive. Warmer temperatures following the period of extensive glaciations, known as the ‘Snowball Earth’, may have also played a part. The consequent rise of sea-levels expanded habitable shallow sea zones. Moreover, the post ‘Snowball’ stage caused an increased availability of minerals and nutrients.

The interaction between abiotic and biotic processes is extremely fascinating and deserves a better understanding – life as we know it depends on it.

Crossing the Mediterranean sea by boat: human dignity and biophysical violence

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This blog was written by Haley Curran, a PhD candidate in Psychosocial Studies at Birkbeck.

MigrationDr Vicki Squire gave a talk at the Birkbeck Institute for Social Research on 29 March, on how the treatment of people on the move in Europe has provided a new lens through which we can understand why there has been no sustainable and humane policy implementation from European leaders, or more pressure from the wider public to address the current migration crisis.

What is biophysical violence?
Biophysical violence relates to the governing of migration through death and derives from Foucault’s notion of biopower and biopolitical racism ‘to make live and let die’. It is a particular governmental regime that separates people into groups- those that are ‘productive’ and those that are ‘unproductive’ and therefore values some groups over others. Biophysical violence can help to mask certain wider policies and practices.

This takes on a racialised form when looking at the refugee crisis in Europe and challenges the notion of Europe as a safe and welcoming space. It also brings the notion of privilege to light and the stark differences between certain groups of people making a journey across Europe compared to others. It is not the same for everyone and certain groups in society will occupy a much more precarious space when they are on the move.

There has also been an emergence of death as a ‘normalised’ concept for certain groups of people migrating and making the journey across Europe. People have been left to die in the name of security.

Biophysical violence also takes into account the significance of physical elements (deserts, seas, inclement weather conditions) which cause the deaths of countless people attempting their journey to and across Europe.

Culpability can also have a role to play in analysing biophysical violence and can perpetuate the ‘normalisation’ of death for certain groups of people on the move:

    • the evasion of culpability- natural forces as a cause of death at borders and along the routes
    • the displacement culpability- shifting the responsibility on to the person making the journey – it’s their fault as they were unable or unwilling to recognise the perils in making that journey
    • the rejection of culpability- the presence of a third actor, such as the people/ person smuggler as the cause of death.

The role of humanitarian responses:
While Search and Rescue missions may be helping to save lives at sea, what happens to those migrants if they are handed over to the authorities and detention centres?

Messaging around pity, sympathy and victimisation can be counter-productive in countering the fear and suspicion in populist sentiment towards people on the move. Humanitarian messaging is dependent on the innocence of the victim and is based on fleeting emotions. Instead they should be looking to create more sustainable interactions based on a relational model of empathy, mutual respect and dignity (politics of empathy & mutual respect). Politics of pity/sympathy can also be present in compensatory reactions to biophysical violence, such as large displays of grief.

Interventions challenging biophysical violence:
Where there is darkness there is also light and hope. The true spirit of humanity counteracts this grim and harrowing picture of violence and aggression with interventions grounded in empathy, dignity and respect.

‘Corridoi Umanitari’ (Humanitarian Corridors) is an initiative that is run by faith groups in Italy. Their focus is on safe and legal routes through assessing people in Lebanon in ‘vulnerable conditions’ (victims of persecution, torture and violence, as well as families with children, elderly people, sick people and people with disabilities) for legal entry to Italian territory with a humanitarian visa and the possibility to apply for asylum. They are flown to Italy and are helped with integrating, housing and learning the language upon arrival.

City Plaza Squat, a squat based in Athens in a disused hotel, houses refugees and activists together. There is a balance of backgrounds, gender, those who may require some support, and those who can provide it. This community does not define people by their ‘vulnerability’ and is a good example of integration and mutual respect.

Final thoughts:
This talk was lively and interesting, throwing up as many questions as it did solutions. There is no easy answer to this complex and politically charged situation and it is going to take creativity and innovation to implement solutions.

What is clear is that a new politics of empathy and respect needs to emerge to address this crisis in a humane way. Human mobility has always been a part of our history and has shaped Europe today, but the right to mobility is currently very unequal.

Safe and legal routes could be one way to address the chaotic and dangerous journeys and may also help to provide some confidence in European decision makers. It will take courage and bravery to take these steps however and it remains to be seen who will take that first step.

The Inaugural BCAM Policy Talk: “Fiscal Buffers, Private Debt and Stagnation: The Good, the Bad and the Ugly” by Giovanni Melina

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This post was written by Veronika Akhmadieva,  an MPhil/Phd Economics student at Birkbeck

One group is targeted for marketing outreach with a bulls-eye under the figures

In 2015, global debt hit a record high of $152 trillion (225% of world GDP), raising the possibility of a new global financial crisis striking the economy in the near future. That prompted the International Monetary Fund (IMF) to conduct an in-depth analysis of global debt and economic growth. The results of this research formed the basis of the inaugural BCAM (Birkbeck Centre for Applied Macroeconomics) policy talk at Birkbeck, given by Dr Giovanni Melina (IMF).

Dr Melina presented an academic paper, a result of his joint work with Nicoletta Batini (IMF) and Stefanie Villa (KU Leuven), that focuses on fiscal buffers, debt and stagnation, and has strong policy implications. In the period from 2002 to 2008, the bulk of the increase in debt of large advanced economies was due to borrowing by the private sector. Then, as some might recall, the Great Recession happened, and the picture changed dramatically; the increase in private debt was rather modest while government debt increased drastically.

A curious mind might wonder why government debt went up during the financial crisis 2007-2008. Dr Melina proposed two possible reasons. The first explanation is based on the denominator effect and on the mechanism of government automatic stabilisers. Government spending, in nominal terms, increased during the financial crisis, partially because more people applied for unemployment benefits, and this in turn boosted government debt. The second explanation derives from the fact that many governments attempted to cover part of private debt – through the recapitalisation of banks, for instance – and that led to the fall in government revenues and the rise in public debt.

“Deleveraging”

The deleveraging is a well-known concept in economics that refers to the process of economic entities reducing their debt to income ratio. The deleveraging of the economy often follows global economic catastrophes, and the financial crisis of 2007-2008 was no exception. Deleveraging can yield important real effects in the economy. Advanced economies can resort to public debt to a very large extent in order to cushion the effects of the negative shocks. For emerging markets raising government debt can be tricky. In some of them deleveraging is still to take place. So what are the best ways for governments to tackle potential deleveraging?

Dr Melina might just have the answer. But first two preliminary questions must be considered – do the levels of private and public debt have tangible effects on output growth? And should government extend financial assistance to credit-constrained agents and firms at times of financial distress?

The paper addresses these questions by first revisiting the literature on the effects of public and private debt on economic growth. Then the authors build a theoretical framework that reproduces the leverage cycle. The authors examine links between private and public debt, in order to capture the mechanisms through which private debt may become public. Finally, the model is used to analyse the effects of government interventions targeted towards financially constrained agents.

Private debt proved to have a negative effect on output. As for public debt, when authors differentiated between high (greater than 95% of GDP) and low public debt countries, they found that when the public debt is low, the government has more room for manoeuvre (more fiscal buffers) and can help to support economic activities in the deleveraging phase. However, if the level of public debt is high to begin with, the further increase is detrimental to the economic growth.

On the question of government financial assistance to credit-constrained agents, it appears that intervention mitigates the extent of the deleveraging and reduces the deflationary effect of the negative house price shocks. Another somewhat counterintuitive finding is that the peak increase in government debt is decreased by government intervention; if government intervenes, it sustains the economic activity and by doing so it reduces its debt. If the level of inefficiency of government spending is high or the level of intervention is excessive, the above may not be true. According to Dr Melina – with about 10% inefficiency costs, the optimal size of intervention is about 7-8% of GDP.

Targeted Intervention

One step further, the authors compare the policy of targeted intervention with other types of fiscal stimuli, such as government investment and government consumption. They found that targeted intervention is more effective in the deleveraging phase, as it is aimed at financially constrained individuals that have high marginal propensity to consume. Hence, most of the funds that are channelled towards these individuals are consumed and that translates into a stronger output effect. Some economies, such as Southern European countries, have limited fiscal space to begin with and can only intervene to a very small extent. These countries may benefit from using limited government funds for targeted intervention rather than increasing the general level of government spending, which might be a less efficient option.

Targeted intervention works best if adequately planned and complemented by appropriate monetary and fiscal policies. In addition, it can be direct, meaning targeted at firms and private sector, or indirect, through banks, recapitalization, asset purchases and guarantees. When banks are in distress, direct targeted intervention might be preferable, because banks may use the funds provided by the government to repair their balance sheets, instead of increasing lending to the private sector.

In practice, targeted intervention might not be the easiest task for governments, as they have to find a way to discriminate between agents, to provide funds to specific firms or industries. Targeted intervention naturally raises moral hazards and competition issues, too. Dr Melina emphasised that targeted intervention is not something to be practised by the government on a regular basis, but should be reserved for disastrous times, when the economy is in distress and in urgent need of stabilisation policies. Could it be that now is just the right time?

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