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Climate Change

Author: Guy Midgley, Chief Director, Climate Change and BioAdaptation Division, South African National Biodiversity Institute

( Article Type: Explanation )


Climate change is now one of the most far reaching sustainable development issues of our times, with implications for the global environment, and for global socio-economic development for decades to come.

It is a challenging issue, and one that presents human society with both threat and opportunity.

It is in almost all senses a complex issue, combining an incomplete scientific knowledge of how climate may change under the influence of greenhouse gas emissions, with the inherent unpredictability of human societal responses, which themselves affect greenhouse gas emissions! Many refer to this intertwined environmental/ socio-economic challenge as a ‘wicked’ problem, meaning one which is highly resistant to resolution due to its complexity, and in the case of climate change, the time frame over which it may play out (decades to centuries).

It is easy to become embroiled in the details of how to predict the possible impacts, and the development of plans of how to cope with and adapt to these predicted impacts (broadly referred to as adaptation responses).

But it is also an issue that has a less complex aspect – it is a reflection of human over-use of natural resources, and so the envisaged solutions to climate change reaffirm that we require new development pathways that address fundamental resource limitations (referred to as mitigation responses, in technical and political ‘climate change’ language).

This notion excites ideological political concerns relating to government intervention in the free market. In other words, it is an issue that challenges sovereign national socio-economic development aspirations, as its ultimate solution requires a ‘cap’ on the emission of greenhouse gases by countries, through limiting their fossil fuel energy use and requirements, and potential revision and adjustment of their land use planning and practices. The attention that the climate change issue is attracting may come as something of a surprise to some people with the knowledge that the climate of our planet has been anything but ‘unchanging’ during the course of the earth’s geological history.
If our planet has seen significant and rapid climate changes in the past, why should we now be concerned? It is very valuable to answer this question, because the answer indicates to us how significant the human impact on our atmosphere, and more broadly on our biosphere has become, especially through human-caused (anthropogenic) climate change. To answer the question of why we now need to be aware and even concerned, we need to understand how the earth’s climate has changed over a range of timescales, and how this relates to the timescale of human evolution, and even more importantly, to the development of modern society. It is now understood that modern human society has developed under an unusually stable climate that has persisted for more or less the last 10 000 years. In response to this relative stability our ancestors changed their lifestyles.

Ancestral lifestyles in many parts of the world shifted relatively rapidly from highly mobile hunter-gathering, to a largely sedentary society that was made possible by the production and storage of excess food – agriculture was invented, surpluses were created, trade and cities followed. Modern society now depends heavily on large scale food production, but also on further developments made possible by this ‘settled’ lifestyle, such as complex fixed infrastructure in enormous cities, national identities and global trade, amongst other things.
If we look more closely at the last 10 000 years, however, what we do see are a few exceptions to the rule of ‘relative climate stability’. These deviations from the rule are important in telling us how sensitive modern human society is to sudden shifts in climate. For example, about 8200 years ago the earth’s climate plunged briefly into a colder spell that is thought to have caused early urbanising societies in the Middle East to abandon advances in agriculture and urban development and revert to nomadic pastoralism. Other shifts that caused increased drought are thought to have caused several advanced societies to collapse some 4000 years ago. These developing modern societies were clearly highly vulnerable to natural climate change. The changes that we could cause to the global climate over the next few decades to centuries are very significant in relation to those that caused these catastrophes in our recent past – and therefore have the potential to disrupt the many systems that we have developed to support modern society. Is modern society any less vulnerable to projected climatic changes?

What can science tell us?
It is now scientifically irrefutable that modern human society has changed the composition of the earth’s atmosphere, and it is almost certain that this is causing climate change. At the dawn of the industrial revolution of the 1800’s modern society began to rely on fossil fuel (coal, in those days) to drive economic development – since then, atmospheric CO2 levels have increased by more than 35%, at a rate that continues to accelerate today. These levels are higher now than they have been for the past several million years, and may rise to levels last seen 30 million years ago, if we continue unabated to burn fossil fuels as a global society. Natural ‘greenhouse gases’ other than CO2 (like methane) have also increased as a result of industry, and farming and forestry practices, and even some new, synthesized greenhouse gases have been added to the atmosphere. As far as we can tell from measurements, the earth’s temperature has increased by about 0.8°C since the industrial revolution, and could increase by a further 0.7°C even if we were to stop greenhouse gas emissions today.
We risk warming the earth’s atmosphere by more than 5°C by the end of this century if our emissions and land clearing practices in tropical forests continue unabated. This outcome would be damaging to modern society, for example by significantly reducing food production in most of the world, introducing a vast array of health impacts from heat stress to disease, challenging water supply and water purification infrastructure, straining disaster risk management and response because of increasing frequency of storms and floods and droughts. Ultimately, effects on sea level rise could disrupt large populations living close to the ocean, including some of the world’s greatest cities. Renowned economist and climate advisor in the UK, Sir Nicholas Stern, estimated that these damages could range from about 5% to as high as 20% of GDP, every year, by the end of this century. Such a high level and rate of warming could also cause poorly understood and unpredictable effects that would result in even faster warming and climate disruption.
It is because of these science-derived insights, incomplete as they may be, that many nations have agreed that a sensible policy would be to keep global warming to below 2°C. This is by no means a universal consensus, as there are many scientific experts who argue that reaching this level of warming could cause damaging effects, especially for small island developing states, low-lying coastal areas such as large river deltas, and vulnerable societies such as in Africa, that face impacts of even rather low rates and amounts of climate change. Because of this, many are calling for a more ambitious international policy response that would assure temperature increases remain below 1.5°C. Such a response would require immediate significant cuts in emissions by all the major emitters of the world, both in developed and developing countries, as there is a roughly 50/50 chance our historic emissions have already committed us to this level of change.

Multilateral negotiations; UN Framework for Climate Change (UNFCCC) and Kyoto Protocol
It is for the reasons stated above, and many others, that the world’s nations are attempting to find a way of stabilising greenhouse gas concentrations in the atmosphere below a level that would ‘prevent dangerous anthropogenic interference with the climate system’, as is stated in Article 2 (the objective statement) of the UNFCCC. These efforts and actions are discussed and developed in multilateral negotiations under the UN Framework Convention on Climate Change, and its related Kyoto Protocol. Discussions are also developing under a further forum, the Ad-hoc Working Group on Long-term Cooperative Action, or the AWG-LCA.
At this time, negotiators have an incomplete consensus that keeping global warming to below 2°C above the preindustrial era will meet the objective of the Convention (based on science currently available). This implies urgent action to reduce emissions, as we have about 1.5°C of warming already observed, and locked into the climate system. The Convention was adopted at the United Nations in May 1992, and opened for signature at Rio de Janeiro in June of that year. The UNFCCC finally came into force on 21 March 1994, and has been ratified by more than 190 nations, making it an almost universally supported Convention (only a handful of nations remain non-Parties). Of these nations, 157 are parties to the Kyoto Protocol and a further five, including the USA, have signed but not ratified the Protocol, and remain non-Parties to the Protocol.
The Kyoto Protocol is an internationally negotiated framework for regulating greenhouse gas emissions of  signatory countries. The Protocol serves the aims of the Framework Convention on Climate Change (UNFCCC) Greenhouse gases specified by the Protocol, namely carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (termed HFCs), perfluorocarbons (PFCs), and sulfurhexafluoride (SF6). The first three gases occur naturally and are part of global biochemical cycles, while the last three are synthetic and used for industrial purposes. The three naturally occurring gases account for roughly 50%, 18% and 6% of the overall warming impact, and their rising levels are caused by fossil fuel use (mainly), deforestation and cement production (increasing CO2), while causes of increasing methane and nitrous oxide levels are far less well understood but likely involve human-driven changes in land cover.&&&&&&& The Protocol originated in December 1997, when representatives of more than 160 countries met in Kyoto, Japan, to negotiate legally binding emission limits for developed nations that aim to mitigate (prevent or avoid) the effects of climate change. In order to enter into force, the Protocol had to be ratified by at least 55 countries representing 55% of global carbon emissions. The USA, responsible for almost 25% of global carbon dioxide emissions, withdrew from the Kyoto Protocol in March 2001, plunging its future into doubt. In July 2001, the EU, Japan, Canada, Russia, and 170 other nations reaffirmed their commitment to the Protocol, and the Marrakech Accords developed at the 7th Conference of the Parties (COP) to the UNFCCC put in place arrangements to increase the potential of flexible mechanisms for achieving compliance by Annex I nations. Russia, responsible for 9% of global greenhouse gas emissions from 1950-90, finally ratified the Kyoto Protocol in November 2004, bringing it into force on 16 February 2005.
The Protocol sets emissions targets for each of the participating developed countries — so-called Annex I countries (including those that have not ratified the convention) -- in relation to their greenhouse gas emissions in 1990. Targets range from an 8% reduction for EU states, 7% reduction for USA, to an 8% increase for Australia and 10% increase for Iceland. Non-Annex I (developing) countries have no targets set by the Protocol, but all parties are encouraged to develop and implement both climate change mitigation and adaptation programmes. Adaptation to climate change impacts is increasingly stressed under both the UNFCCC and Kyoto Protocol, as science suggests that very significant cuts in emissions are needed to achieve CO2 stabilisation in the atmosphere at 450 ppm. This is the CO2 level that current science tells us will provide a 50/50 chance of keeping global warming to below2°C1.
Emissions targets for Annex I countries must be achieved on average over the so-called ’first commitment period‘, running from January 2008 to December 2012, in order for them to be in compliance with the Protocol. If compliance is not achieved in the first commitment period, the target deficit plus a penalty of 30% must be made up in the second commitment period. The Protocol allows for flexibility in meeting targets by Annex I countries, such as providing credits for carbon storage in carbon ’sinks‘ (also termed ‘sequestration’) through land afforestation or reforestation, allowing international emissions trading (e.g. through the use of carbon markets), putting in place a Clean Development Mechanism (CDM) to allow greenhouse gas reducing technologies to be introduced in developing countries, and allowing countries to meet their emissions targets jointly. The first commitment period of the Kyoto protocol ends soon. Currently, Kyoto Protocol negotiations centre on a range of issues, but chiefly on the shape of the Kyoto regime post-2012, and specifically on broader participation in emissions reductions (mitigation) arrangements. South Africa’s position has been to favour a ’twin-track‘ approach, one track involving more stringent emissions targets for Annex I countries (bolstering Kyoto), and the second enhancing support for developing countries to allow them to do their fair share in mitigation and to address adaptation needs, and to bring the USA into a multilateral regime. It is clear, however, that leading companies, cities and regional initiatives, including many in the USA, are rapidly implementing the spirit of the Kyoto Protocol and achieving emission reductions while increasing efficiencies and profits, providing hope that this form of innovation will accelerate the achievement of the goals of the UNFCCC and the Kyoto Protocol.

It was hoped that intensive negotiations would deliver a more inclusive climate deal by the UN Conference of © Graeme Williams/ Africa Media Online the Parties (COP) in Copenhagen in December 2009. While negotiations had advanced on the key issues necessary to develop this deal, it proved too early to finalize it, and instead most nations supported the ‘Copenhagen Accord’, which is a short document outlining key needs for a climate regime, but which lacks clarity on many mechanisms and targets. The Accord was not adopted by the COP because of disagreement by a small number of Parties, and the Accord was only ‘noted’ by the COP. Nonetheless, elements of the Copenhagen Accord were incorporated into AWG-LCA texts during the Conference of the Parties in Cancun in December 2010. Currently, these negotiations have delivered commitments or stated aspirations by nations, through the provision for statements of commitment and/or aspiration by Parties under the Copenhagen Accord. These currently would have a 50/50 chance of keeping warming globally to about 3.2°C. Much more would need to be done to ensure that the broadly (but not universally) accepted 2°C target is reached, for this process to happen in a fair and equitable way, and for it to have a good chance of succeeding.

Ecosystems and biodiversity as solutions
In southern Africa, we reap the benefit of multiple services provided to us by high biodiversity ecosystems. The value of these services is almost never accounted for by traditional economic analysis, although this situation is beginning to be addressed by the fields of environmental and ecological economics. These services are both potentially under threat from climate change, while at the same time providing potential and already realised benefits to human society in through mitigating and adapting to climate change. Many ecosystems now existing in the oceans and on land have evolved largely under the cool conditions of the past few million years.
A sudden change to the climate, we believe, will have at least some adverse impacts, and possibly substantially damaging effects on the support base for almost all life on the planet. There are some exceptions to this overall rule, with some plant types (especially trees) likely to benefit from rising atmospheric CO2 levels and possible increases in temperature and rainfall.
But these benefits are likely to be limited to high latitudes in the northern Hemisphere where cold temperatures limit tree growth. The benefits also do not come without costs that may be far more catastrophic – a good example is the poleward migration of natural insect ‘pests’ such as the pine bark beetle in North America, which has caused the die-back of millions of hectares of previously unexposed natural and managed forests. Under the post-Montreal COP negotiations (since December 2005), new ideas and concepts entered discussions on achieving the objective of the UNFCCC, which have started to focus on natural and semi-natural ecosystems and biodiversity as climate change solutions. The first major new concept, introduced in Montreal, was the agenda item on ‘Reducing Emissions from Deforestation in Developing Countries (RED)’ which has since expanded to be referred to as ‘Reducing Emissions from Deforestation and Degradation’, and including concepts of disincentivising deforestation where this is not yet underway (REDD+). The REDD+ discussions recognise that more than 20% of greenhouse gas emissions and reductions in long term carbon uptake capacity by ecosystems through photosynthesis are due to deforestation in developing tropical countries.
Turning around the deforestation trend, and rehabilitating degraded tropical forests could therefore contribute substantively, and relatively quickly. Advances in remote sensing of land cover from space have made monitoring and verifying the implementation of this approach possible – the main reason such an approach was excluded from discussions under the Kyoto Protocol during the 1990’s. It is possible that this approach will establish a market mechanism similar to the Clean Development Mechanisms of the Kyoto Protocol. Apart from REDD+, which relates to mitigation, discussions on adaptation are increasingly taking the use of ecosystems and biodiversity to help society to adapt to climate change.
Referred to as ‘Ecosystem based Adaptation (EbA)’ it is envisaged that practices that focus on maintaining, enhancing and restoring ecosystems and their biodiversity may be critical in increasing the resilience of environments to climate change, thus buffering people from the worst effects. This exciting concept has been developed by the World Bank, the IUCN, and recently was a topic of the Convention on Biological Diversity, which has contributed to cross-cutting

UNFCCC/UNCBD activities on ecosystems and climate change. Ecosystem based Adaptation was officially agreed as a significant new topic in inter-sessional negotiations in Bonn June 2011 during meetings of the Subsidiary Body on Scientific and Technological Advice (SBSTA). This topic will be elaborated under the Nairobi Work Program on Adaptation under auspices of the UNFCCC SBSTA, a signal of the promise of development of this concept. Overall, in order to counter the potential vulnerability of ecosystems, biodiversity and related societal practices and needs to climate change, it is clear that environmental and ecosystem management and husbandry will increasingly be a key part of national, regional and international action on climate change adaptation and mitigation.

Adaptation options
Our scientific knowledge of these possible impacts is far from complete, and therefore we are not yet in a position to generate detailed plans of how we aim to cope and adapt. But this does not mean that we cannot plan at all. The key here is to use what we know in ways that will create the space for us to adapt appropriately as we start to see how climate may change, and how the world around us, natural and ‘engineered’, begins to respond. We need to use our predictive knowledge of climate change and its impacts as a rough guide, not as a precise template, all the while trying to refine the guidance as much as possible. We need to focus on flexible responses that keep our future options open, and that are aligned with real present day societal needs.
To succeed in this endeavour, we need to create the institutional ability and national capacity to refine our predictive knowledge, through modelling both the climate and projected impacts, and through piloting early response actions, such as bolstering early warning systems and disaster risk reduction and response actions that make sense even under current climatic conditions.
We need to start learning, fast, how to engage productively and effectively in this area.

Mitigation options
These are far more certain and well understood than adaptation options. The world needs collectively to wean itself off its fossil fuel dependence, at least initially through increasing energy efficiency and by developing cleaner fossil fuels, such as gas and possibly ‘clean coal’. Clean coal requires a substantive investment in fairly complex technologies that will strip CO2 from large emission sources such as power stations and store the carbon in a form that is as close to inert as possible. One way envisaged is to pump this stripped CO2 into geological formations at depth.
A further well understood but controversial option is to increase the global fleet of nuclear power plants, especially those with new ‘fast breeder’ technologies that reduce fuel waste by up to 90% below previous generation technologies. Recent (and more distant) events relating to plant safety and the dire consequences of plant failures, such as due to difficult to foresee challenges such as tsunamis, have caused a shift in some countries, notably Germany, against what was a growing re-emergence of nuclear power as a climate change solution. Finally, investments in renewable energy systems, both national and local, are increasingly emerging as a big part of a long-term solution to both climate change and energy security challenges faced by the world’s nations.
Increasingly, these solutions are being sought at local level, such as through the growing group of cities that are engaging in international cooperative programs. These trends are promising, as they offer more than 50% of the world’s population (those urbanised) better quality of life while also addressing the climate change challenge in one of the most significant sectors for greenhouse gas emissions. 1 The safe level is correctly defined in terms of CO2 equivalents (CO2e). This is necessary because there are 6 gases concerned, and they all cause a different level of warming per unit concentration – their warming potential (averaged over 100 years) is therefore converted to an equivalent CO2 concentration.