The Sixth Mass Extinction

The Battle for Hope in the Anthropocene

Some musings by Jethro Gauld, Ph.D. Researcher at the University of East Anglia.

The footprint of human activity is now felt in every region and ecosystem on earth from the bottom of the oceans to the tallest peaks and even high up into the atmosphere. Because of this, many scientists now think we have departed from the Holocene, which refers to the previous 13,000 years or so and entered into a new, much less stable, geological epoch termed the Anthropocene1,2 where humans are very much in the driving seat of the earth’s systems.

During lockdown, while everyone else was worrying about Covid-19, I had the ongoing sixth mass extinction on my mind3. While I should have been focussing on my Ph.D. working to improve our understanding of the risks to birds from wind farms and power lines as we transition away from fossil fuels. I experienced days and sometimes weeks where doubt nagged at me, distracted me from my work, made me question my hopes for the future and appear distant from conversations with people I care about. I would surmise the feeling as a sense of weariness and anxiety associated with how little progress is seemingly being made to halt biodiversity loss and prevent runaway climate change. These feelings are not new but without the distractions of ‘normal life’ they became more intense. From conversations with colleagues and others working in similar fields it seems that I am not alone. I sense a growing despondency and weariness in fellow academics, scientists, ecologists, those involved in conservation, policy and environmental activism. It feels like despite the best efforts of those working in these areas, society as a whole is putting sticking plasters on these problems rather than meeting them head on with the ambition required. Meanwhile industry lobbyists, populist politicians and neo-liberal economists seem set on removing even the most basic environmental protections, hard won over decades but all too easily removed with the mark of a pen. So, how do we win the battle for hope in the Anthropocene?

First, we need to face up to the situation we are in; we are facing an unprecedented global emergency. Despite pledges to reduce carbon emissions by a significant number of countries, the concentration of carbon dioxide and other gases continues to increase each year. Since pre-industrial times we have increased the amount of Carbon Dioxide in our atmosphere by 50% to 415ppm (NOAA 2020). This is higher than at any point in the last 3 million years and certainly beyond anything our species (Homo sapiens) has experienced in our ~300,000 year history. Last time greenhouse gas concentrations were this high, average global temperatures were approximately 3 degrees Celsius warmer and sea levels were approximately 20 metres higher 4.

Mean carbon dioxide concentration for February 2020 and trends since circa 1960 (NOAA 2020).

As we exceed 1°C warming above pre-industrial levels we are starting to see the impacts of this on how we live. Earlier this year, Britain experienced disastrous winter flooding followed by one of the driest May’s on record and broke several temperature records in June, July and August. A warmer, wetter atmosphere is driving these more extreme weather patterns. In the polar regions, which are warming faster than other latitudes, we are seeing record reductions in sea ice cover and melting permafrost. This year temperatures in the high thirties were recorded numerous times in the Arctic Circle, smashing previous records (Pinto, 2020) contributing to the collapse of an ice sheet bigger than New York in the Canadian Arctic 5. In California, the Arctic, Australia and the Amazon we have also witnessed record wildfires occurring. We are entering a new climate zone beyond the niche in which we humans evolved and certainly beyond what our civilisation is built to withstand 6.

In addition to this, biodiversity loss driven mostly by land use change and overexploitation has been increasing in recent decades as demand for resources has grown exponentially. Since the 1970’s populations of vertebrate animals have more than halved 7. Extinction is a natural process but our demands on the planet and cavalier destruction of ecosystems are causing extinctions to occur at equivalent rates to that experienced during the end Permian mass extinction (375 million years ago), this event wiped out ~95% of life on earth.

This is a problem because we need healthy ecosystems to allow human civilisation to thrive. They provide services such as pollination and regulation of the water cycle, which are vital for agriculture. They absorb our wastes and lock away carbon, helping stabilise our climate while cleaning air and water in the process. They also provide us with spaces to clear our minds, which is vital for our mental health. Ecosystems are like complex JENGA towers. Each species being a block in that JENGA tower representing a function crucial to the overall health of the ecosystem and therefore the ability of that ecosystem to provide the services we rely upon. There is built in resilience in healthy ecosystems, as there will be overlap in the functions performed by different species. As a result, we often do not notice the impacts of extinction until we have removed too many blocks in the tower and it comes crashing down around us. We see this manifest most clearly, when fish stocks collapse or when intensive agriculture wipes out the pollinators in an area causing crops to fail. In summary, we need nature and eroding it is eroding our own survival chances.

Some climate scientists think we may have avoided a worst-case climate change scenario due to a shift away from coal and the Paris Accord 8. But without concerted action to further cut emissions this decade, we are set on a trajectory toward a 3 – 4 degrees Celsius rise in temperature above pre-industrial levels by the end of the century 9–11. This would take us beyond the threshold where we could stabilise the earth’s climate due to feedback mechanisms in the climate system (Figure 2). These feedback effects include loss of ice replacing a reflective surface with a dark surface, which retains more of the heat from the sun. Four degrees Celsius warming means no more coral reefs, no more Amazon rainforest and huge shifts in the patterns of rainfall and ocean currents, devastating farming and fishing. Sea level rise and desertification would displace billions of people. London would be underwater. The loss of life and loss of species would be horrific.

None of this is inevitable, yet, the IPCC highlights that if we want to have a good chance of limiting further warming to between 1.5 and 2 degrees Celsius we need to halve global greenhouse gas emissions from human activity by 2030 (IPCC 2018). This alone will not be enough to protect biodiversity; we also need to improve how we manage landscapes, including protected areas, more equitably with other species 7. This challenge brings with it a huge opportunity for us to invest in a new low carbon economy, develop nature based solutions, create rewarding green jobs in sustainable industries, reconnect with our communities and create a fairer society. The longer we leave it, the faster and harder we will need to shift to zero carbon. Delaying action is a false economy 12.

Figure 2: From Steffen et al. 2018. Possible future pathways for the earth system. Limiting warming to well below two degrees would give us a good chance of returning the earth system to a pre-industrial climate within human timescales (a few generations). Whereas continuing our current trajectory makes it more likely that, we will trigger a runaway shift to a hothouse earth state, which would essentially be irreversible for millennia. 

Why have governments been slow to act? First and foremost is that we have built a global economic system wedded to the concept of ever increasing GDP (Gross Economic Product) and governments perceive anything that could potentially reduce GDP is inherently bad 13. The reason politicians and economists are keen on GDP as a measure of progress is because in recent centuries increasing GDP has generally been correlated with increases in welfare 13,14. In this sense, increasing GDP can be good. However, correlation does not equal causation. GDP is a very simplistic measure purely based upon the volume of “things” being produced and consumed. It does not account for the consumption of natural resources and energy, the production of wastes or social consequences. This causes a myopia in decision making whereby policies which boost GDP in the short term are often favoured 14,15 because through the lens of neo-classical economics, many influential economists have habitually downplayed the costs of inaction in their calculations 12. The problem is that we live on a planet with finite resources and a finite capacity to process our wastes. When we exceed this capacity, the natural systems our civilisation relies upon begin to bend and break. Solving climate change and biodiversity loss requires us to recognise these planetary boundaries and how our human system should not outgrow the capacity of the earth to support it 15. Fortunately research in areas such as “Natural Capital”, “Ecosystem Services”, “Circular Economy”, and “Doughnut Economics” is fostering new collaborations between ecologists and economists to come up with a better measure of progress than GDP 14,16.

A second major reason for the slow response to environmental problems is denial of the problem due to interference from industry. In the 70’s and 80’s when the relationship between climate change and burning fossil fuels was first properly understood by the scientific community17. Instead of investing in electrification or renewable energy, the response from fossil fuel companies was to double down and spend billions on attempts to discredit climate science and seed doubt in the media, general public and politicians 18. Although the this kind of outright denial has largely been discredited 9,19, it has probably cost us at least two decades in which we could have already made significant strides toward halting climate change and biodiversity loss.

A third reason is a less obvious way in which the transition to a more sustainable economy has been delayed through more subtle forms of denial or minimisation of the problems. These are summarised in a recent paper by Lamb et al., 2020 19 on the “Discourses of Climate Delay”. These arguments include framing the problem as a matter for individuals to change their own behaviour to distract from structural issues preventing people from living sustainably, understating the problem and overstating the costs of climate action by pundits such as Bjørn Lomborg, greenwashing where governments and companies set ambitious targets without backing them up with policy or investment, putting our faith in future technological innovation rather than deploying existing technology or “doomism” where people justify a lack of action with an attitude that it is too late to make a difference. These more subtle forms of climate denial are still commonplace and must be challenged if we are to close the gap between the science and the policy.

My view is that in essence, most environmental problems are a consequence of prioritising short-term convenience or profit over long-term survival and prosperity. To survive and thrive as a species, the next step in our evolution must be to implement systems to switch those priorities around, or at least align the two. We need to recognise that putting nature first is not to the detriment of people but central to our own wellbeing. We have a choice of two futures: one could be a bright future where we restore the ecosystems we have systematically degraded over the 20th century and power our economies with cheap, abundant renewable energy or through inaction to protect biodiversity and halt climate breakdown we face a future of scarcity, war, conflict and extinction.

On a personal level, the dichotomy of these two possible futures plagues my decision-making and I know I am not alone. I feel that my generation is one for whom the very possible prospect of a biosphere incapable of supporting complex civilisation within the next century casts a shadow over our aspirations. In choosing where to live, will we have to factor in projected future sea level rise? In choosing a career we cannot know whether it will be of any use in a world altered by climate change? Do we bother setting aside money for a pension? Do we reproduce? Is it moral to bring a child into the world when there is a strong possibility that they will witness the breakdown of civilisation as we know it? Or should we take the gamble in the hope that despite many fits and starts humanity will claw itself back from the brink? In reality, we are forced to hedge our bets. Younger generations may not even that luxury.

To rebuild hope, firstly, we need to recognise that change is inevitable. Whether we like it or not business as usual cannot continue. The edifices of our financial system are crumbling in the wake of Covid and if we rebuild them as they were we will witness them crash about our ears again as climate change and biodiversity loss begin to bite. If we want to thrive as a species, we should take the opportunity presented by the covid-19 crisis to hasten the demise of this unsustainable system. Out of the rubble, we can build something better. Governments can no longer cry wolf about not being able to deploy vast resources to address a crisis, we have literally just seen them do that.

This is no longer purely an issue of science. While further research is vital to advance our understanding of the natural world and solve specific problems, we now have a good understanding of why climate change and biodiversity loss are happening, a number of tools in the box to address them and an idea of the cost of the different scenarios in front of us. This is now largely a communication problem, those of us working in this area need to reach out to other disciplines to help more effectively communicate the changes we are observing in the natural world to people outside of our professions, why it matters and how we protect and restore ecosystems. We won’t convince everyone. In the words of Colin Tudge in his book the Variety of Life “I do not believe there is a “good” reason that will satisfy everybody or that many people will find convincing. In the end you just have to believe that it is right to conserve our fellow creatures” but we don’t need everyone. We just need to convince enough people to create a critical mass calling for change and call out those trying to delay it. The good news is that more and more people are choosing to raise their voice for the biosphere. It is all to play for, we understand the problem, we have many solutions at hand the main barrier is shifting the window of political possibilities 20.

If you value the natural world now is the time to take action in whatever way you feel able. This is the most empowering thing you can do to regain hope if you are feeling despondent. If you are an academic, it can be as simple as being more proactive about communicating your research findings to a wider audience who may already be looking for answers. It can be as simple as talking about it to friends and family. If you can be more motivated, join whatever civil society group you can to push for change. Whether it be Greenpeace, Friends of the Earth, RSPB, Surfers Against Sewage, WWF or Extinction Rebellion to name a few. Volunteer with a local conservation group to help restore habitats near you. Pick something you can fix or make better and do it. This is active hope, by working to help nudge humanity toward a more positive future you build hope in yourself too as you realise that you are not as alone as lockdown led you to believe at times. For UK readers, one easy thing you can do right now is ask your MP to support the climate and ecological emergency bill and do not take no for an answer


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Jethro Gauld, Ph.D. Researcher at the University of East Anglia. @Gauldblimeyjet

“I’m currently a Ph.D. student at the University of East Anglia working to better understand where and when birds are most at risk of collision with wind farms and power lines so we can mitigate these risks as we transition away from fossil fuels. I previously worked in Ecological consultancy in Scotland specialising in ornithology and mammal survey. I hold a BSc (hons) in Ecology and Conservation and an MSc in Ecosystem Services. I have been involved in environmental activism and voluntary conservation work for many years prior to working in the field. I am increasingly frustrated with the gap between the urgency of the science of climate change and biodiversity loss and the response from industry, governments and civil society. Despite this, I remain a stubborn optimist that we can fix this”.