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Environmental Law and Policy in Namibia: Towards Making Africa the Tree of Life (Third Edition)




Oliver C. Ruppel

1 Introduction

During the past centuries the world’s population increased rapidly to over 7 billion in 20111 and a global population of 9.5 billion people is projected for the year 2050.2 The expansion of mankind, both in numbers and per capita exploitation of the earth’s resources, has been astounding. In an age primarily shaped by people, the so-calledAnthropecene3 , the depletion of natural resources, the transformation of land surface by human action, and the increase in atmospheric concentrations of carbon dioxide are some of the impacts of human activity on Earth and atmosphere. The consequences of human activity are inseparably linked with observed changes in climate and mankind is faced with enormous challenges posed by the effects of climate change4 ,de facto and de iure .5

The following sections introducing the climate change Chapter focus on human vulnerability in Africa and on the Africa-specific findings of the Intergovernmental Panel on Climate Change (IPCC) established by the United Nations Environment Programme (UNEP) and the World Meteorological Organisation (WMO) in 1988.

2 Aspects of Human Vulnerability in Africa

The African continent, in particular the SADC region, is one of the poorest in the world despite being richly endowed with natural resources. Approximately 45% of the total SADC population lives on US$1 per day. Malnutrition is around 36.1%, ranging from 44 to 72% in the some countries of the region. Life expectancy is just below 40 years, and declining. Infant mortality rates remain above 50 per 1000 births in most countries in the SADC region. These figures are indicative of the harrowing and impoverished conditions afflicting most peoples in the region.6

Various regions of Africa have experienced changes in weather patterns over recent years, especially concerning the occurrence of droughts and floods.7 This has led to property destruction, loss of crops, livestock and settlements, as well as to forced human displacement, all of which have exacerbated already grinding poverty. Vulnerability to climate change8 relates not only to a change in the frequency or duration of climatically unusual conditions, but also to the capacity to respond adequately to such conditions. Two aspects of vulnerability can be distinguished. The first concerns the likelihood that an individual or group will be exposed to and adversely affected by altered climatic conditions. The second aspect of vulnerability relates to the capacity to anticipate, cope with, resist and recover from the impacts of climate change. This capacity to adapt to climate change obviously varies among regions and socio-economic groups, in the sense that those with the least capacity to adapt are generally the most vulnerable to the impacts of climate change. This, to a great degree, speaks to the nature and abundance of the resources available to a given group, individual or region, to mitigate, overcome or adapt to altered climate conditions. Climate change has an impact on socio-economic development, and it affects various sectors crucial to such development – water availability, forestry, agriculture, biodiversity, food security and human health. Human vulnerability has become a key focus of human rights discussions, which now also tend to focus on how flooding, devastated housing, changes in the supply of fresh and irrigation water, contagious diseases, prolonged droughts, forced migration, deforestation, soil denudation, etc., will impact on human lives.9

Projected consequences of continued temperature increases include a rise in sea levels, changes in precipitation patterns, and the resultant threat to food security and sustainable development in general, with more people pushed into and caught in poverty, especially in developing countries with fragile economies.10

One of the major natural resource implications of climate change is that human populations – and the law – will have to adapt to significant shifts regarding fresh water resources, especially where population concentration will create or exacerbate conditions of water scarcity. Almost four decades ago water law expert Frank Trelease wrote, in the context of climate change:

While one function of law is to give stability to institutions and predictability to the results in action, often the strength of law will lie not in immutability but in capacity for change and flexibility in the face of new forces.11

It is not clear whether climate change in Africa will be pushing the hydro-climate beyond the capacity of existing water resources in future. However, again in the words of Trelease, “We would be wise to plan for the unpredictable”.12 It is expected that the ‘water side’ of climate change is likely to generate a significant impact on national and global economies; and it is not unlikely that this will result in increased local and international conflict, particularly in Africa.13

This may also affect the energy production sector, as water is closely connected to the generation of electricity. An important question repeatedly posed is whether an increase in hydro-electric and nuclear electricity generation will have the required effect of a decrease in greenhouse gas emissions. In fact, the increased water requirements of these kinds of energy generation – to run turbines and for cooling – might exacerbate pressures on already strained water reserves and create new constraints. The interconnectedness and interdependence of water, energy, national welfare and international economies becomes clearer as climate change progresses around the world.

Moreover, the potential consequences of climate change and a decrease in fresh water also pose challenges for animal and plant species and biodiversity,14 which in turn is likely to influence the human food chain.15 All these considerations call for global level scrutiny and perhaps for a new and global green deal16 that reassesses development in a carbon-constrained17 and water-stressed world.

Various studies highlight the vulnerability of Africans that depend primarily on natural resources for their livelihoods, indicating that their resource base – already severely stressed and degraded by overuse – is expected to be further adversely affected by climate change.18 Populations already vulnerable as a result of their status – women, children, the aged, minorities and the disabled – will be feeling the effects of climate change the hardest.19

Women in Africa are especially exposed to climate change related risks due to existing gender discrimination, inequality and inhibiting gender roles.20 Elderly women and girls are expected to be most severely affected. Women are vulnerable to gender-based violence during natural disasters and during migration, and girls are more likely to drop out of school when household incomes and resources come under stress. Rural women are expected to bear the brunt of considerable negative effects on agriculture and deteriorating living conditions in rural areas. This vulnerability is exacerbated by factors such as unequal property rights, exclusion from decision-making and difficulties in accessing information and financial services.

With regard to African children, climate change is expected to increase existing health risks and to undermine support structures that protect children from harm. Extreme weather conditions and scarcity of safe drinking water are major causes of malnutrition and infant and child mortality in Africa. Likewise, increased stress on livelihoods will make it more difficult for children to attend school.21 Girls will be particularly adversely affected as traditional household chores, such as collecting firewood and water, require more time and energy when resources are scarce.

Climate change also poses a threat to indigenous peoples in Africa, who often live in marginal lands and fragile ecosystems, which are particularly sensitive to changes in weather.22 Climate change could become a driver of migration and population displacement and it is acknowledged that indigenous people living in dry-lands are among the most vulnerable communities, as a result of water scarcity. Indigenous peoples have been voicing their concerns about the impacts of climate change on their rights as distinct peoples, and the importance of giving them a voice in policymaking on climate change at both national and international levels; further, to take into account and to build on their traditional knowledge. Customary law23 and indigenous knowledge should therefore be incorporated into climate change policies in order to foster the development of cost-effective, participatory and sustainable adaptation strategies.24

Populations whose rights are poorly protected are likely to be less well-equipped to understand or prepare for climate change; they would be less able to lobby effectively for Government or international action; and are more likely to lack the resources needed to adapt to expected change in their environment and economic situation. The efforts that have been made so far to place rights at the centre of any future climate change-mitigating dispensation have not been human rights focused. However, human rights impacts are a relevant concern. To mobilise the policy value, and indeed the legal force, of human rights in the construction of a climate change mitigating dispensation, requires the assessment of likely human rights impacts and outcomes of climate change. The specific rights potentially affected by climate change, such as rights to food, water, shelter, and health or rights associated with gender, children and indigenous peoples, must be addressed in context. Each of the human rights25 affected by climate change need to be identified and addressed in order to infuse relevance into on-going consultations, political negotiations, global cooperation discussions and other actions, whether internationally, regionally and nationally.26

Rights and responsibilities regarding the utilisation of environmental resources need to be distributed with greater equity among communities, both globally and nationally. In this context, political participation, access to information and broad public involvement are just as important to the realisation of human rights as the development of quality climate change related education and interdisciplinary research of high standard. In order to become a winner – rather than a loser in the face of climate change – Africa needs more highly skilled experts in this field in order to meet future demand and to be in a position to adequately negotiate around its international interests in a growing and complex, knowledge-based global economy.27

3 Findings of the IPCC

It is the ultimate role of the IPCC to assess – on a comprehensive, objective, open and transparent basis – the scientific, technical and socioeconomic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation.

Only recently, the IPCC has launched itsAssessment Report (AR5) on Climate Change,28 with the contribution by Working Group I onThe Physical Science Base in 2013, the contribution by Working Group II onImpacts, Adaptation and Vulnerability in 2014, and the contribution by Working Group III onMitigation of Climate Change . In its report, the IPCC has again most rigorously reviewed and assessed the most recent scientific, technical and socioeconomic information produced worldwide relevant to the understanding of climate change.

The aforementioned reports are of great relevance with regard to all aspects of climate change and contain a solid base for further debate on this important topic. A general message from the reports can be summarised as follows: there is no doubt that we live in a world which is altered by climate change, one of the greatest challenges of the 21st century. Climate change poses risks to human and natural systems and has the potential to impose additional pressures on the various aspects of human security.29 The risks and impacts related to climate change can be reduced by improving society to decrease vulnerability and hand down the overall risk level (adaptation30 ) and by reducing the amount of climate change that occurs, particularly by decreasing emissions (mitigation31 ).

Human influence on the climate system is clear, and recent anthropogenic emissions of greenhouse gases are the highest in history. Recent climate changes have had widespread impacts on human and natural systems.32

Evidence shows that the atmosphere and ocean have warmed, the amounts of snow and ice have diminished and sea level has risen and there is no doubt that human influence has been the dominant cause of the warming observed since 1950.33 Climate change has caused widespread and consequential impacts on all continents and across the oceans and poses a broad range of future risks for human and natural systems.34 The IPCC’s analysis of observed climate trends and future projections reveals that that it is very likely that mean annual temperature has increased over the past century over most of the African continent,35 and that temperatures on the continent will rise faster than the global average increase during the 21st century.

3.1 Main Findings for Africa

Selected Executive Summary Statements of the IPCC AR5 Africa Chapter36

Evidence of warming over land regions across Africa, consistent with anthropogenic climate change, has increased (high confidence). Decadal analyses of temperatures strongly point to an increased warming trend across the continent over the last 50 to 100 years.

Mean annual temperature rise over Africa, relative to the late 20th century mean annual temperature, is likely to exceed 2°C in the Special Report on Emissions Scenarios (SRES) A1B and A2 scenarios by the end of this century (medium confidence). Warming projections under medium scenarios indicate that extensive areas of Africa will exceed 2°C by the last 2 decades of this century relative to the late 20th century mean annual temperature and all of Africa under high emission scenarios.

A reduction in precipitation is likely over Northern Africa and the southwestern parts of South Africa by the end of the 21st century under the SRES A1B and A2 scenarios (medium to high confidence). Projected rainfall change over sub-Saharan Africa in the mid-and late 21st century is uncertain.

African ecosystems are already being affected by climate change, and future impacts are expected to be substantial (high confidence). There is emerging evidence on shifting ranges of some species and ecosystems due to elevated carbon dioxide (CO2) and climate change, beyond the effects of land use change and other non-climate stressors (high confidence). Ocean ecosystems, in particular coral reefs, will be affected by ocean acidification and warming as well as changes in ocean upwellings, thus negatively affecting economic sectors such as fisheries (medium confidence).

Climate change will amplify existing stress on water availability in Africa (high confidence). Water resources are subjected to high hydro-climatic variability over space and time, and are a key constraint on the continent’s continued economic development. The impacts of climate change will be superimposed onto already water-stressed catchments with complex land uses, engineered water systems, and a strong historical sociopolitical and economic footprint. Strategies that integrate land and water management, and disaster risk reduction, within a framework of emerging climate change risks would bolster resilient development in the face of projected impacts of climate change.

Climate change will interact with non-climate drivers and stressors to exacerbate vulnerability of agricultural systems, particularly in semi-arid areas (high confidence). Increasing temperatures and changes in precipitation are very likely to reduce cereal crop productivity. This will have strong adverse effects on food security.

Climate change may increase the burden of a range of climate-relevant health outcomes (medium confidence). Climate change is a multiplier of existing health vulnerabilities (high confidence), including insufficient access to safe water and improved sanitation, food insecurity, and limited access to health care and education. Climate change is projected to increase the burden of malnutrition (medium confidence), with the highest toll expected in children.

In all regions of the continent, national governments are initiating governance systems for adaptation and responding to climate change, but evolving institutional frameworks cannot yet effectively coordinate the range of adaptation initiatives being implemented (high confidence). Progress on national and subnational policies and strategies has initiated the mainstreaming of adaptation into sectoral planning. However, incomplete, under-resourced, and fragmented institutional frameworks and overall low levels of adaptive capacity, especially competency at local Government levels, to manage complex socio-ecological change translate into a largely ad hoc and project-level approach, which is often donor driven. Overall adaptive capacity is considered to be low. Disaster risk reduction, social protection, technological and infrastructural adaptation, ecosystem-based approaches, and livelihood diversification are reducing vulnerability, but largely in isolated initiatives. Most adaptations remain autonomous and reactive to short-term motivations.

Growing understanding of the multiple interlinked constraints on increasing adaptive capacity is beginning to indicate potential limits to adaptation in Africa (medium confidence). Climate change combined with other external changes (environmental, social, political, technological) may overwhelm the ability of people to cope and adapt, especially if the root causes of poverty and vulnerability are not addressed.

There is increased evidence of the significant financial resources, technological support, and investment in institutional and capacity development needed to address climate risk, build adaptive capacity, and implement robust adaptation strategies (high confidence). Funding and technology transfer and support is needed to both address Africa’s current adaptation deficit and to protect rural and urban livelihoods, societies, and economies from climate change impacts at different local scales. Strengthening institutional capacities and governance mechanisms to enhance the ability of national governments and scientific institutions in Africa to absorb and effectively manage large amounts of funds allocated for adaptation will help to ensure the effectiveness of adaptation initiatives (medium confidence).

Climate change and climate variability have the potential to exacerbate or multiply existing threats to human security including food, health, and economic insecurity, all being of particular concern for Africa (medium confidence). Many of these threats are known drivers of conflict (high confidence). Causality between climate change and violent conflict is difficult to establish owing to the presence of these and other interconnected causes, including country-specific sociopolitical, economic, and cultural factors. For example, the degradation of natural resources as a result of both overexploitation and climate change will contribute to increased conflicts over the distribution of these resources. Many of the interacting social, demographic, and economic drivers of observed urbanization and migration in Africa are sensitive to climate change impacts.

3.2 Impacts of Climate Change

AR5 presents strong evidence that the impacts37 of climate change in Africa are already being felt across various sectors. Climate change poses challenges to economic growth and sustainable development and to the various facets of human security. Although detection of and attribution to climate change are often difficult given the role of drivers other than climate change, there are substantially more impacts in recent decades now attributed to climate change.38 Various examples show, however, that climate change exerts extensive pressure on different ecosystems such as terrestrial, freshwater, and coastal/ocean ecosystems.39 The health, livelihoods and food security of people in Africa are all affected by climate change. And as “Africa as a whole is one of the most vulnerable continents due to its high exposure and low adaptive capacity”,40 innovation and technology, smart policy making, high levels of Government attention, effective diplomacy, and international cooperation are required in order to effectively address the current and future challenges related to climate change.

3.3 Future Risks

Climate change will amplify existing risks and create new risks for natural and human systems. Risks are unevenly distributed and are generally greater for disadvantaged people and communities in countries at all levels of development.41

Risk is “the potential for consequences where something of value is at stake and where the outcome is uncertain, recognizing the diversity of values.”42 Risk results from the interaction of vulnerability, exposure, and hazard. Risks from a changing climate in general come from a lack of preparedness making people vulnerable and the exposure of people or assets to harm, overlapping with triggering climate events (hazards). Key risks are potentially severe impacts of climate change and are considered ‘key’ due to the high intensity of hazard or the high vulnerability of societies and systems exposed, or both. One major finding of AR5 is that the higher the increase in warming is, the higher is the risk.43

Particular challenges for less developed countries and vulnerable communities, given their limited ability to cope are the key risks as identified in AR5 as risks with high confidence, spanning sectors and regions, including but not limited to the following:44

  • Risk of death, injury, ill-health, or disrupted livelihoods in low-lying coastal zones and small island developing states and other small islands, due to storm surges, coastal flooding, and sea-level rise;
  • Risk of severe ill-health and disrupted livelihoods for large urban populations due to inland flooding in some regions;
  • Systemic risks due to extreme weather events leading to breakdown of infrastructure networks and critical services such as electricity, water supply, and health and emergency services;
  • Risk of mortality and morbidity during periods of extreme heat, particularly for vulnerable urban populations and those working outdoors in urban or rural areas;
  • Risk of food insecurity and the breakdown of food systems linked to warming, drought, flooding, and precipitation variability and extremes, particularly for poorer populations in urban and rural settings;
  • Risk of loss of rural livelihoods and income due to insufficient access to drinking and irrigation water and reduced agricultural productivity, particularly for farmers and pastoralists with minimal capital in semi-arid regions;
  • Risk of loss of marine and coastal ecosystems, biodiversity, and the ecosystem goods, functions, and services they provide for coastal livelihoods, especially for fishing communities in the tropics and the Arctic;
  • Risk of loss of terrestrial and inland water ecosystems, biodiversity, and the ecosystem goods, functions, and services they provide for livelihoods.

For Africa in particular, the following key risks have been highlighted:45

  • Risks of stress on water resources,
  • sea level rise and extreme weather events,
  • shifts in biome distribution,
  • degradation of coral reefs,
  • reduced crop productivity,
  • adverse effects on livestock,
  • vector- and water-borne diseases,
  • under nutrition, and
  • migration.

4 Opportunities for Effective Action to Reduce the Risks Associated to Climate Change

The risks associated with climate change need to be reduced by limiting the rate and magnitude of climate change. AR5 reveals that risks are reduced substantially under the assessed scenario with the lowest temperature projections. Furthermore, reducing climate change can also reduce the scale of adaptation that might be required.

In order to manage the risks of climate change, various approaches for adaptation come into consideration. Risk reduction strategies used in African countries to offset the impacts of natural hazards on individual households, communities, and the wider economy include early warning systems, emerging risk transfer schemes, social safety nets, disaster risk contingency funds and budgeting, livelihood diversification, and migration. Various adaptation approaches can be overlapping and are often pursued simultaneously. Most national governments in Africa are initiating governance systems for adaptation. Efforts to reduce vulnerability include disaster risk management, adjustments in technologies and infrastructure, ecosystem-based approaches, basic public health measures, or livelihood diversification.

Building more resilient societies is another means to cope with the challenges associated with climate change. Climate change, along with land-use change, degradation of ecosystems, poverty and inequality is one of the stressors that impinge on resilience. Climate resilient pathways have to be identified by decision-makers that lead to a more resilient world,inter alia through adaptive learning, increasing scientific knowledge, effective adaptation and mitigation measures, and other choices that reduce risks.

5 Concluding Remarks

Changes in Africa’s climate have been observed during the past decades and impacts are occurring across a variety of sectors such as ecosystems, human health, livelihoods and food security. Climate change will generate new risks and amplify existing risks for society and the environment. Africa must prepare for future changes in climate as even under low-emission scenarios, warming will continue at least until around the middle of this century. The impacts of climate change can be reduced through adaptation actions moderating the harm of climate risks and exploring new opportunities. Risk management must be in the focus of decision-making in order to cope with the impacts and risks related to climate change. On the positive side it should be noted that the experience of adaptation measures on the African continent is growing as governments are increasingly developing National Adaptation Plans of Action and other national adaptation policies. Furthermore, opportunities for low-carbon, climate-resilient development are increasingly being explored and realised.

Africa is most vulnerable to climate change due to the existence and interaction of multiple stresses – endemic poverty, complex governance and institutional dimensions, limited access to capital, markets, infrastructure and technology, ecosystem degradation, complex disasters and conflicts and low adaptive capacity. Yet, as a global problem, climate change calls for multilateral solutions as opposed to unilateral approaches, in particular if these are confrontational. Differentiation through emissions targets and additional multilateral obligations under policies and other measures in the climate sector is key to addressing leakage and competitiveness concerns. A scientific consensus is emerging that a substantial reduction in greenhouse gas emissions will be required to prevent an extreme increase in average temperature. It is also acknowledged that a business-as-usual scenario would have disastrous consequences for future generations. Although the on-going international negotiations around climate change-related initiatives centre largely on which countries will reduce their emissions, consensus is emerging that it is primarily the responsibility of developed countries to reduce their greenhouse gas emissions first, while – in line with the principle of common but differentiated responsibility – developing countries make specific policy commitments.

At the same time, it is clear that required global emissions reductions cannot be achieved in developed countries alone. Developing countries will have to reduce emissions as well, especially China and India. As a consequence, developed and developing countries will have to transform themselves into low-carbon economies over the long run. This will require efforts at various levels, including substantial changes in lifestyle, in particular in industrialised countries. Equally important is major investment in low carbon technology and modern technology transfer to and capacity building in Africa.46 Robust scientific knowledge about climate change plays an overarching role. By means of effectively and objectively assessing such scientific knowledge and prevailing uncertainty, the IPCC can provide the world with the best possible and much-needed evidence of climate change-related impacts.


1 See UNFPA (2011).

2 According to the 2012 Revision of the United Nations World Population Prospects, UNDESA (2012).

3 The term has initially been coined in 2000 by the famous atmospheric chemist and Dutch Nobel Prize winner Paul Crutzen and has ancient Greek roots:anthropo meaninghuman andcene meaningnew . In 2000 Crutzen realised that we live in an age primarily shaped by people and that anthropogenic drivers have become major factors regarding the changes of our planet Earth. Crutzen suggested this age be calledAnthropocene – “the age of man”. See Crutzen / Stoermer (2000).

4 According to the IPCC (2014b:1758), climate change refers to “a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcings such as modulations of the solar cycles, volcanic eruptions, and persistent anthropogenic changes in the composition of the atmosphere or in land use. Note that the Framework Convention on Climate Change (UNFCCC), in its Article 1, defines climate change as: ‘a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods’. The UNFCCC thus makes a distinction between climate change attributable to human activities altering the atmospheric composition, and climate variability attributable to natural causes.”

5 See Ruppel (2013:29).

6 SADC (2008).

7 Cf. Haensleret al . (2010:2-4) for a climate history of Namibia and western South Africa.

8 The IPCC defines vulnerability as the “propensity or predisposition to be adversely affected. Vulnerability encompasses a variety of concepts and elements including sensitivity or susceptibility to harm and lack of capacity to cope and adapt.” IPCC (2014:5).

9 Passage taken from Ruppel (2010a).

10 Ibid.

11 Trelease (1977).

12 Ibid.

13 Scholtz (2010).

14 Hinz / Ruppel (2010).

15 Erenset al. (2009:207).

16 Barbier (2010).

17 Palosuo (2009).

18 Ibid:85; Learyet al . (2006).

19 Ruppel (2010a,b).

20 Ruppel (2008b, 2010d).

21 Ruppel (2010b).

22 Cf. studies on Biodiversity in Hinz / Ruppel (2008a).

23 Ruppel (2010c).

24 Mfune et al. (2009b).

25 Ruppel (2008a).

26 PIK Report (2010).

27 Ruppel (2010a).

28 Report available fromhttp://www.ipcc.ch/report/ar5/; accessed 28 May 2014.

29 Adger / Pulhin (2014:760).

30 Adaptation is defined as “The process of adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to moderate or avoid harm or exploit beneficial opportunities. In some natural systems, human intervention may facilitate adjustment to expected climate and its effects.” See IPCC (2014b:1758).

31 Mitigation of climate change is defined as “A human intervention to reduce the sources or enhance the sinks of greenhouse gases.” See IPCC (2014b:1769).

32 See IPCC (2014a:2).

33 IPCC (2014a:2).

34 IPCC (2014a:6).

35 With the exception of areas of the interior of the continent, where the data coverage has been determined to be insufficient. See Niang / Ruppel (2014:1206).

36 Taken from Niang / Ruppel (2014:1202-1204).

37 Impacts of climate change are the “effects on natural and human systems of extreme weather and climate events and of climate change. Impacts generally refer to effects on lives, livelihoods, health, ecosystems, economies, societies, cultures, services, and infrastructure due to the interaction of climate changes or hazardous climate events occurring within a specific time period and the vulnerability of an exposed society or system. Impacts are also referred to as consequences and outcomes. The impacts of climate change on geophysical systems, including floods, droughts, and sea level rise, are a subset of impacts called physical impacts.” IPCC (2014c:5).

38 IPCC (2014a:7).

39 See Niang / Ruppel (2014:1214).

40 Niang / Ruppel (2014:1205).

41 IPCC (2014c:13).

42 Ibid:5.

43 Niang / Ruppel (2014:1238).

44 IPCC (2014c:13).

45 See Niang / Ruppel (2014:1237).

46 Ohlendorf / Gerstetter (2009).