More than once Dr Stringer has stated that climate change is the defining challenge of our times. Personally I couldn’t agree more, but in 2016 the media focus (perhaps understandably) has been on the seismic political shifts on either side of the Atlantic. However, with the official confirmation that 2016 was the hottest year on record (breaking the record for a third year in a row) now seems an apt time to reflect on reports linked to climate change in 2016. Analysing the various climate related stories from the previous year reveals grounds for optimism in terms of our progress towards slowing (and eventually reversing?) the warming trend, as well as reasons to be much more pessimistic.

 

Initially announced at the end of 2015 the historic Paris agreement, signed by 194 countries, has provided a renewed global framework for managing climate change, whereby countries have committed to trying to limit global warming to no more than 2o (the more ambitious 1.5o target already seems improbable given that we have already warmed roughly 1o since the Industrial Revolution). During 2016 countries began to formally ratify the agreement, with the UK becoming the 111th to ratify the agreement in November; at the time of writing 125 countries in total have ratified the agreement, taking the treaty past the 55 signatories needed for it to become legally enforceable. Of potentially greater significance was the fact that both the USA and China have now formally ratified the agreement, submitting their proposals for cutting carbon emissions and helping to fund mitigation strategies in developing countries.  China’s ratification sent a strong signal to the developing world as they committed to peaking their carbon emissions in 2030. The USA famously refused to ratify the Kyoto protocol (a forerunner of the Paris agreement), fatally undermining its impact; the symbolism of the USA ratifying the agreement sent a clear, positive message to other countries. Perhaps the Paris agreement will form the foundation finally for effective, coordinated global action to tackle climate change?

 

Of course an instant rebuttal to the above would be to consider the potential impact of the inauguration of President Trump on America’s climate policy, particularly in the context of his infamous ‘Chinese hoax’ tweet. At this point it is worth stating that the anthropogenic forcing of climate change is no longer seriously debated, with 97% of actively publishing climate scientists agreeing that climate warming trends are likely to be the result of human activities (for the pedants that seize on the word ‘likely’ as a reason for inaction I refer them to this argument by David Mitchell). The election of such a senior politician espousing climate denial is clearly unhelpful in tackling climate change, but perhaps it is not as important an event as some fear (in a climate context that is; the geopolitical implications of President Trump are to my mind terrifying). For a start China has simply reaffirmed its own commitment to sustainable growth and now talks openly about replacing the US as the global climate leader; China has genuine ambitions to be recognised as a global power and its politicians seem to recognise the extent of the threat posed by climate change, so perhaps their rhetoric will be matched by reality? Secondly there are strong centres for positive action within the US, most notably the large state of California, with their Governor, Jerry Brown stating ‘We’ve got the lawyers and we’ve got the scientists and are ready to fight’. Thirdly, and perhaps more fundamentally, even Trump will struggle to completely revive the fortunes of the coal industry; investors aren’t stupid and Goldman Sachs’ warning that ‘peak coal is near’ and ‘the industry does not require new investment’ probably means the point from which we will permanently be burning less of this most polluting of the fossil fuels is not too distant.

 

Indeed evidence that progress in addressing global emissions is being achieved was the reported third year in a row without an increase in carbon emissions, therefore does this mean 2016 represented a more positive turning point in the fight against climate change? Unfortunately, the answer is almost certainly no, with one reason being that much of this was attributable to a decline in demand for Chinese manufacturing, with the likelihood of a concurrent increase in emissions again once demand increases. More fundamentally, was 2016 the year we began to realise we had focused too much on carbon dioxide? Scientists have now discovered that over the last 10 years there has been a rapid rise in methane concentrations within the atmosphere; this is relevant because methane is twenty times as potent as carbon dioxide in terms of its greenhouse effect. Unlike carbon emissions we do not have such clear monitoring strategies for methane.

Methane concentrations are higher in the northern hemisphere because both natural- and human-caused sources are more abundant there. Photograph: AIRS/Aqua/Nasa

 

At this point it seems important to cover two fundamental geographical concepts; these are positive feedback loops and tipping points. Positive feedback is where an initial change in one direction causes additional changes in the same direction (for example interest on a savings account used to cause the money to grow, causing more interest to be paid on the savings). Within climate change a number of positive feedback loops exist, with perhaps the best example being the melting of the permafrost as a result of the accelerated rate of climate warming in the Arctic. Melting of the permafrost releases methane trapped in the peat for thousands of years, causing further warming and therefore further permafrost melting. Scientists worry that soon we may reach a climate tipping point, whereby so many greenhouse gases have been emitted that positive feedback amplifies the warming to such an extent that runaway climate change (more than 2oc warming) is unavoidable.

 

Observations of the Arctic sea ice in 2016 provided a stark reminder that our polar regions are already changing more quickly than most scientists predicted; in November it was predicted that the North Pole was a staggering 20oc warmer than average. Whilst this will surely prove to be an anomaly, the implications for a significant reduction in sea ice this year help to further highlight positive feedback as the warming temperatures melt the sea ice and will probably lead to a record sea ice minimum next summer over the Arctic Ocean. This will reduce the albedo effect (reflection of incoming solar radiation), thus enabling further warming of Arctic waters; a further example of positive feedback.

 

So was 2016 a positive year for climate change or are we now all doomed? (I use this hyperbolic term as it is so often the way the question is phrased to me). Clearly I don’t have a crystal ball, but I feel confident enough to assert we are not doomed. To clarify, by we I mean those of us lucky enough to live in this benign mid latitude climate. A warming world seems likely to bring more unpredictable weather, more heatwaves, more frequent and powerful storms (but not hurricanes) to our shores. This will bring more flooding, more water shortages and very significant challenges for agriculture, but should not pose insurmountable obstacles to a developed economy.

 

However if geography is taught properly it should remind us that the world is unequal and that the impacts of climate change in tropical and particularly sub-tropical regions are predicted to be much more severe; it has been reported that climate change could, for example, make the Middle East and parts of North Africa uninhabitable, surely driving refugee movements that dwarf any historical precedent. What 2016 taught me was that whilst we are responding as a species to climate change the planet is also responding, amplifying our changes – these changes will continue even as we cut emissions; regardless of whether 2016 was positive or negative for climate change the need is as urgent as ever to go further and faster in cutting emissions (of all greenhouse gases), whilst we still have a world our children would want to inherit.

 

Mr James Earp, Head of Humanities