​Earth Day began in 1970, founded by U.S. Senator Gaylord Nelson as a teach-in to educate students, with a wider aim of bringing environmental considerations into the public eye. Nelson had been inspired by the large-scale student anti-war movement across America, and realised that this was a path through which environmental considerations could be brought to the national political agenda.

​Ecological debt is defined as the level of resource consumption and waste discharge by a population which is in excess of locally sustainable natural production and assimilative capacity. The term was coined in 1992 by the Insituto de Ecologia Politica in Santiago, Chile, wherein the production of greenhouse gases by the developed nations of the north was seen as inequitable. This was exacerbated by utilisation in the north of resources extracted in the south which imposed climatic and social changes not included in the calculations of international debt. Subsequently, a rich versus poor argument emerged, asserting that the impact of exploitation of finite natural resources from these nations had not been fully ‘compensated’ by price, royalties or licensing fees. Surrounding this was a series of ‘debt for nature’ agreements wherein some parts of a nation’s debt was erased in return for the designation of large wilderness areas. However, due to the inherently interrelated nature of ecology and ecosystems, ecological debt has now transcended the physical and political boundaries of any individual nation to become a global phenomenon that involves every person on earth in calculating the suggested debts through collective and individual behaviours worldwide. 

Euan Graham

Today marks the six-month anniversary of Michael Gove’s appointment as Environment Secretary­­. In the past, Gove had shown a fairly poor voting record on environmental issues, voting against a ban on “unconventional petroleum exploitation” and alongside that voted against a motion explicitly requiring environmental permits for natural gas fracking operations. The MP also had no previous experience in agricultural or environmental roles, previous roles being Justice and Education secretary, so his promotion sparked outcry from many. Ed Davey, the former Environment secretary, described the appointment as ‘an act of environmental vandalism’, and said it would be ‘like putting a wolf in charge of the chicken coop’.
 
The looming prospect of Brexit makes for uncertain times in the realm of UK environmental policy, and so in many ways Gove’s tenure takes place at a truly pivotal moment. So, what has he achieved since June?

As humans we are pretty good at living at a range of temperatures, adapting to life at most latitudes and able to find insulation and shelter or cool ourselves in the shade, as and when we get uncomfortable. Of course, the targeted maximum of a 2°C increase of global average temperature set down in the Paris Climate Agreement isn’t an attempt to limit the risk to the structural integrity of ice-creams on July afternoons. Preventing a global temperature increase of this kind is about avoiding human tragedies on a massive scale, from whole islands and cities being engulfed by rising seas, droughts that destroy vital crops year after year, and extreme weather events that flatten homes and lives. The 2°C mark, despite being an objective and quantifiable change, is therefore largely symbolic. Stepping away from global increase to a more local, less apocalyptic scale – in the city of Oxford for example – I imagine people would probably welcome such a modest increase in temperature when braving the wind and rain on their daily commutes.

Localised warming, however, even to the tune of just a few degrees, can be bad news for other less generalist species than humans. Although many species are capable of adapting their behaviour and physiology to new temperature ranges, many more require very specific conditions to survive. Such species typically live in high biodiversity areas, like rainforests, where each species fulfils a very particular ecological niche – eating specific species, foraging or hunting using a very specific method, living in specific places, and so on. This means that small changes, if they occur too quickly for a population to adapt, can have profound consequences.

In Queensland, Australia, for example, the rainforests are home to a great diversity of possum species. One of these species, the green ringtail possum, P. archeri, (pictured) is found only at elevations above 300m limited by its inability to successfully regulate its body temperature at warmer lower altitudes. This is because it has ‘adaptive heterothermy’, meaning that as temperatures rise above and beyond 30°C it ceases to increase its rate of perspiration, in an attempt to avoid severe dehydration. The narrow ecological niche of the green ringtail possum restricts it to the forest canopy, where it obtains most of its fluid from eating foliage. Poisonous compounds in the leaves it eats – a defence against overgrazing – stop the possum from quickly rehydrating itself, eating less often so it has time to break down the harmful compounds it ingests. These possums evolved over many millennia to take advantage of a highly stable ecosystem and climate, which favoured adaptive heterothermy. But with localised warming in the Queensland region, this fine balance is being disturbed, and the green ringtail possum and other species are being constrained to smaller and smaller territories at higher altitudes, which can’t support the same number of possums.

Proving the influence of climate change on ecosystems is a relentlessly difficult task, especially when there are other major forms of human disturbance at work. The complex web of interactions between living and non-living factors in an area often produces chains of effect that can magnify the effect of localised warming. In Hawaii, the destruction of lowland habitats to make way for agriculture has forced most native bird species uphill to habitats on the mountain slopes. However, the current threat to the birds is no longer agriculture, but avian malaria carried by an introduced species of mosquito, C. quinquefasciatus. As the malarial parasite can only successfully infect new hosts at temperatures above 13°C, the native birds are only contracting malaria at middle elevations, preserving refuges in the highest areas. Incremental localised warming, however, is already robbing them of this sanctuary, and famous birds such as the Hawaii creeper (pictured) are becoming endangered. The retreat of specialist species uphill to cope with rising temperatures is doomed to be a losing game. Although for some of them are still able to expand upwards, at some point their islands in the sky will shrink to nothing and their retreat will be halted once and for all.


​Relevant studies: Krockenberger et al. (2012) ‘The limit to the distribution of a rainforest marsupial folivore is consistent with the thermal intolerance hypthesis’; Benning et al. (2002) ‘Interactions of climate change with biological invasions and land use in the Hawaiian Islands: Modeling the fate of endemic birds using a geographic information system.’

Harry Holmes

In Yorkshire chainsaws run at dawn, residents scramble outside, realising that a terrifying crime is about to take place, a tree is to be felled. In Sheffield there is an ongoing battle to protect the nature that line the streets of the northern city since an agreement was signed in 2012 between Amey (an outsourced company) and the Labour run Sheffield council to organise the maintenance of the roads in the area. This has recently culminated in a battle to prevent the felling of trees by this company, organised often by local resident volunteers who seek to do all they can do in a peaceful capacity to prevent the chopping down of the trees. What is unique in this battle to my eye is that rarely has there been such intersection between environmental concerns and other social causes and campaigns.  

The agreement is a 25 year long private finance agreement (PFI), a controversial way of organising the provision of government projects where they are provided by the private sector using public sector money. Not only does this introduce the profit motive into the maintenance of goods previously run for the public interest but it also removes the traditional methods by which the state was held accountable. When a state failed to provide a service or acted against the public interest it could be held accountable through the usual political methods of elections and lobbying. Now a private provider not only is not held politically accountable but can often lock themselves in as the only provider through the drafting of the agreements to last 25 years like the Sheffield case. No matter the pressure or change in government often the case may be that a council is contractually obliged to deal with the private company. Residents complain they have not been consulted by the felling firm and that the wishes of the community are being ignored.

Then early this year the pressure on the protesters increased, and arrests were made of those more active in preventing tree removal. These figures would scramble to stand around any tree under threat to prevent anybody damaging them. They were arrested under trade union legislation which criminalises anyone who persistently stops someone from carrying out lawful work. The amount of peaceful protests which could be considered illegal under this law does not bare thinking about. Luckily charges were dropped, and now the protesters are suing the police force in return. But now the high court has recently intervened with an injunction against the activity of surrounding the trees, leading to a counter blockade of a depot in Sheffield by protesters. One of those arrested was in fact a Green party Sheffield councillor, leading to even greater anxiety in the community, concerned about how they could respond. Even Michael Gove recently said he wanted to see an end to the felling of the trees, though the Labour council dismissed his demands.

The debacle has made one thing clear, the issues of privatisation and outsourcing whilst traditionally considered economic or social justice issues, in this case also intersects with environmental concerns about maintaining green spaces. Trees have a huge role in urban planning, not merely for aesthetic purposes but as sequesters of greenhouse gases and air pollutants. Forests remain one of the best ways to prevent flooding, a bigger and bigger concern as sea levels rise. There have been many identified mental health benefits of green spaces, as well as their purpose in educating communities about the importance of nature and ecosystems.

In a society that increasingly seeks to privatise things held in common, be it nature, healthcare or education there is simultaneously a breaking down of the barriers that kept the groups protecting them separate. In Sheffield you can find anti-privatisation protesters alongside human rights defenders all under the banner of increased environmental protection and democracy. The model of protest used in Sheffield remains one which is local, communities protecting their trees, but it also shows glimmers of being a broad tent movement in defence of nature.

If you want to find more about the crisis in Sheffield check out the campaign website here: https://savesheffieldtrees.org.uk/

British waters are home to a diverse array of marine biodiversity, providing a variety of habitats for species from sheltered sea locks to deep-water coral. Importantly, the marine life populations these habitats support are vital for local livelihoods and industries, from fishing and trade to tourism. Yet these valuable waters have become increasingly under threat from unsustainable economic and harvesting activity, and, critically, challenges presented by climate change. 

How are British waters valuable ecologically?

British waters, from inland estuaries to the deeper waters offshore, are home to over 330 different types of fish, from species occupying fundamental roles at the base of the food chain to wonders such as basking sharks, dolphins and Atlantic grey seals and a diverse array of birdlife.
 
Where does climate change come into this?

As greenhouse gas emissions continue to increase, climate change is accelerating, having serious effects on the world’s weather systems and conditions and putting the delicate balance of many of the world’s natural ecosystems and habitats, including those of British marine life, at risk.

Home to a diverse range of marine and dependent terrestrial species, it is vital that we keep our oceans healthy, both to support the species they are home to and the industries and livelihood that depend on them. The ocean performs a variety of invaluable- and, crucially, irreplaceable- ecosystem services: for instance, around half of the oxygen we breathe is produced by the sea, or specifically by phytoplankton, and absorbs around half of manmade CO2.

However, due to the complexity and scale of the problem of climate change, and the fact that we still know so little about our planet’s oceans, there is no quick solution. Despite covering 71% of the Earth's surface, our knowledge of the effects of climate change in oceans is limited compared to terrestrial ecosystems, making the problem harder to tackle and the scale of the impacts harder to predict. Attempts to address climate change need to work with related issues such as overfishing and pollution of the seas- the WWF, for instance, has already developed initiatives to bring together actors from governments, science, industry, and stakeholders to find sustainable ways of managing our shared marine environment. In this way, it is important to understand the threats the world’s oceans are facing as a problem that cannot solely be addressed by tackling climate change- if our world’s oceans are to remain sustainable for future generations and marine biodiversity, the issue needs to be tackled in all its complexity.
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Climate change continues to pose a significant threat to British marine life, whether directly as a result of changing marine conditions of indirectly through adverse effects on prey distribution. Atlantic Grey seals, for instance, often sighted in colonies around UK waters, are experiencing threats as a result of changing distributions of their prey, particularly sand eels, for which they will come into increasing competition with fishermen and other predators as prey availability dwindles. 

Other terrestrial species reliant on marine environments and ecosystems are also expected to be affected: coastal erosion and flooding are already posing threats for species such as the Atlantic Grey seal, where rising sea levels are seeing the the isolated shingle beaches that grey seals favour to give birth to their pups in the autumn become narrower, increasingly the likelihood of pups being washed away. Internationally important breeding colonies of terns that nest close to the sea edge are also at risk from rising sea levels and increasing stormy weather. Wetland birds are also at risk: species such as the redshank will find their habitats inundated by the sea while moors and wet grasslands will dry up during hot summers, all of which carry wider implications for the food web and are expected to see changes in migration patterns in response to the stresses brought by habitat change in response to global warming. 

The vast effects of climate change in these areas has been observed in particular in the Orkney islands. Warming of British waters offshore is thought to have completely altered the plankton regime, meaning dependent species such as sand-eels have nothing to feed on. As a result, sand-eel numbers have dropped dramatically and seabirds are struggling to find food.
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Our oceans remain a vital resource for both livelihoods, economic activity and, crucially, biodiversity, and exist in a complex relationship with our atmosphere and natural ecosystems. Attempts to address climate change therefore need to take into account how changes implemented at one site carry repercussions for the rest of the ocean system. While this is by no means an easy undertaking, it remains crucial that our world’s oceans are healthy and protected from overexploitation and pollution, the effects of which will only become more severe in light of climate change and continue affect wildlife in British waters.