Overview of Regional Climate Change in Africa

Submitted by Sukaina Bharwani | published 25th Mar 2011 | last updated 30th Mar 2011
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Introduction

This short overview of climate change issues in Africa was written by Ben Smith and Anna Taylor in 2009 as input to an Environment and Climate Change policy brief to inform the development of Sida's regional development assistance strategy for sub-Saharan Africa.

Where not explicitly stated this brief builds on work from the AMCEN (2008) Climate Change Adaptation in Africa: Scoping paper for the Expert Group Meeting and various IPCC AR4 chapters (esp. WGI, Ch 11, WGII Ch 9)

Recent assessments place Africa as a priority for climate adaptation assistance due to the high number of least developed countries, fragile resources, Africa's large share of the world's drylands, highly variable climates and relatively weak institutions for managing the multiple stresses related to climate change vulnerability. Across Africa the vulnerability of certain groups of people to climate related stresses is already unacceptably high, and projected climate changes indicate this vulnerability could increase dramatically, and new vulnerabilities will emerge, unless appropriate adaptation measures are taken.

Understanding the figures: observed and projected climate change

Climate observations show that there has been a trend of increasing average temperatures across almost all of Africa since the 1960s, associated with a decrease in the number of cold days and nights and an increase in the number of warm days and nights. The changes in annual rainfall over Africa present a more varied picture. West Africa and much of central Africa has experienced a marked decline in annual precipitation, southern Africa shows no clear long-term trend, while east Africa shows patterns of increasing rainfall over the northern sector and declining amounts over the southern sector. There has been an increase in the number of droughts, and in southern Africa the number of extreme rainfall events has increased, leading to severe flooding.

Projections of anthropogenic climate change in Africa are still largely based on results from global circulation models, as there have been few studies using regional models or empirical downscaling experiments[1]. Model projections for temperature are better than those for precipitation, as many models find it hard to accurately capture aspects of African climatology that affect rainfall, such as dust aerosol concentrations, sea-surface temperature anomalies, the role of vegetation and land-use change, deforestation in the equatorial region, and soil moisture in southern Africa.

The IPCC projections show that average temperatures are expected to increase in the range of 3-4ï‚°C for the period 2081-2099 over most of Africa, with smaller increases in coastal and equatorial regions. These increases are likely to vary locally and seasonally, however, and the possibility of greater increases cannot be ignored. Along with increases in average temperatures, the maximum and minimum temperatures and the numbers of extremely hot days and seasons are also expected to increase. Uncertainty associated with changes in precipitation make it difficult, for example, to provide any precise estimation of future runoff, especially in arid and semi-arid regions where slight changes in precipitation can result in dramatic changes in the runoff process. However modelling results do indicate an expected increase in precipitation over East Africa and parts of Central Africa, and a decrease in austral winter precipitation in southern Africa. Projections for West Africa range from a large increase to a large decrease in precipitation, and the IPCC state that projections of precipitation for West Africa should be 'viewed with caution'. Annex 1 provides two tables giving more details of observed and projected climate changes as reported in the IPCC Fourth Assessment Report, for each of the four regions of sub-Saharan Africa.

Key issues relating to climate change

Impacts of climate change in Africa are increasingly common, especially in melting glaciers, decreased river flows, the spread of vector-borne diseases and decreased crop yields. Many of Africa’s major economic sectors (e.g. agriculture, forestry, fisheries, tourism, construction, etc.) are sensitive in various ways to weather and climate conditions and large portions of the continent’s population are involved, to varying degrees, in subsistence livelihoods making them highly vulnerable to climate and other environmental changes. Levels of vulnerability to climate change, as socially differentiated across populations, are compounded by existing problems, particularly:

  • developmental challenges, such as endemic poverty, weak governance, limited access to capital and markets, low levels of infrastructure and technology;
  • natural resource management challenges, including land degradation, decreased soil fertility, degraded riverine systems, inequitable access to water resources, and loss of biodiversity;
  • health threats, particularly HIV/AIDS; and
  • complex disasters and conflicts.[2]

By 2020, between 75 and 250 million people are projected to be exposed to increased water stress due to climate change. The overall increase in numbers of people exposed to water stress will be particularly marked in southern (and northern) Africa, but important local scale variations will exist; central to this is not just variations in the amount of rainfall received but in the ability to capture and store rainwater. Negative impacts on local livelihoods and national economic productivity will be felt through: the inability to irrigate commercial crops or water livestock; the spread of water borne diseases, the burden of household labour of walking long distances for water collection; limited water for mining and manufacturing purposes; etc. Many of these impacts undermine efforts to reduce poverty and fuel development at both the local and national scale.

Agricultural production and access to food, is projected to be severely compromised by changes in the timing and duration of precipitation events, daily temperatures, and levels of soil moisture. In some countries, yields from rain-fed agriculture could be reduced by up to 50%. This would further adversely affect food security and exacerbate malnutrition. Subsistence-based farming systems are expected to be at greater risk than the commercial sector, much if which is under irrigation and thereby able to manage reductions in rainfall, however as the markets change so food prices are likely to increase, affecting food access, especially for the poor.

The increase in heavy rainfall events and any change in cyclone activity under climate change, is associated with more frequent and extensive flooding across much of the continent, with crippling consequences for households, communities and the local and even national economy. Mobility is reduced, access to food and water is limited, public and private infrastructure is damaged, crops and livestock are lost, and people are often temporarily (or permanently) displaced. For example, the floods of 2000 in southern Africa had a devastating impact, particularly in parts of Mozambique where the cost of the combined impact of the floods and the cyclones in 2000/2001 was estimated at US$ 600 million and more than 500,000 people were displaced. Towards the end of the 21st century, projected sea level rise will affect low-lying coastal areas with large populations (especially in places of rapid urbanisation) through permanent or periodic inundation.

A number of impacts on terrestrial and aquatic ecosystems are being observed, partly attributable to climate change, and more are expected. The extent of ice caps on Mt Kilmanjaro and the Rwenzori mountains is declining and could ultimately disappear, reducing water availability in those areas. In mountain, forest, grassland and wetland ecosystems climate change is expected to result a loss of certain plant, animal and bird species. Also in marine ecosystems, increased water temperatures lead to coral bleaching, the reduction and eventual loss of various fish species. All these species loses have negative implications for important economic sectors such as fisheries, forestry and tourism, as well as impacting on food security and ecosystem integrity.

Human health is expected to be adversely affected by projected climate change, especially in Africa where current capacity to administer preventative and curative health care is dangerously low. Increasing temperatures will extend the habitats of disease vectors such as mosquitoes carrying malaria. More intense droughts and floods will result in more extensive outbreaks of water-borne diseases, like cholera, particularly where sanitation is poor. There are also multiple complex interactions between the prevalence of HIV and AIDS and climate change, both in terms of climate change impacts increasing the likelihood of risky behaviour and exposure to HIV infection and HIV/AIDS affected people having a decreased capacity to adapt to climate change impacts. The links between health and climate change are not yet well researched in the region.

It is important to recognize different levels of vulnerability within communities and households associated with gender, age, HIV status, ethnicity, etc. For example, in peri-urban Malawi, when rains are insufficient and crop yields are low, significant numbers of women resort to sex-for-food transactions to secure food for their families, leading to an increase in the spread of HIV. The recognition of cultural and social dynamics is therefore of paramount importance when supporting adaptation to climate change.

Relationships between climate change and existing conflicts

The relationships between climate change, environmental degradation and conflict are complex and as yet poorly understood. Environmental factors are rarely the sole source of conflict, but changes in natural resources linked to climate change have been implicated as one of the causal factors in the current crisis in Darfur[3]. The transboundary nature of major water resources in many regions of Africa has the potential to be the seeds of future conflict. As climate change and socio-economic factors shift the balance between water supply and demand strong regional coordination in the management of river basins and water resources will be needed to negotiate the equitable allocation of the available water and minimise disagreement between upstream and downstream countries that could potentially lead to conflict. Food security could be another point of conflict, for example cattle raids become more frequent during events that compromise food security, such as droughts[4]. Also, the intra-regional transfer of staples (e.g. maize) is important in making up deficits in countries that have suffered poor harvests (especially a few seasons running), so if the region as a whole becomes more food insecure these coping mechanisms are likely to be compromised, potentially leading to conflict.

There is growing recognition that environmental degradation and climate change hold the potential to result in significant population displacement, which the world is presently ill-equipped to prevent or respond to in an effective manner. Africa will be at the forefront of many of these concerns. Current policy responses tend to focus on how to deal with the impacts of sudden natural disasters rather than with the consequences of longer term environmental degradation. While migration is a coping (or adaptation) mechanism and survival strategy for those who move, increased migration may itself contribute to further environmental degradation, socio-economic and political stress. This practical but highly complex and chronic issue has largely been ignored by the climate change research community (it is not covered in any detail by the IPCC AR4) but is likely to become a major policy challenge of this century. Adequately planning for and managing environmentally induced migration will be critical for human security.[5]

Key actors and activities

Various levels of government in Africa are starting to address issues of climate adaptation and disaster risk reduction, but many of the policy and programmatic interventions are externally driven and financed, such as the UNFCCC National Adaptation Programme of Action (NAPA) process and large pilot programmes developed by the UN agencies, international finance institutions and alike. These international undertakings provide a starting point for mobilising government activity around climate change issues, but the connections are often not made between international, regional and national initiatives and local realities.

Regional bodies, including SADC and the AU, are beginning to establish groups mandated with addressing climate change, formulating policy on climate-related issues and engaging in international decision-making on adaptation financing. This is all very new and progress is expected to be slow in terms of translating this into action on the ground. However, these regional forums may prove important for influencing positions in the international negotiation process and for addressing many of the transboundary climate change impacts (including directing the research agenda and facilitating coordinated interventions, drawing on strengths distributed across the region). The African Ministerial Conference on the Environment (AMCEN) provides a permanent forum where African Ministers of the Environment discuss matters of relevance to the continent and climate change is now firmly on their agenda. African Ministers of Finance are also meeting in May focussing on climate change, which shows increasing political will to tackle the issue. A number of international and regional networks are being established to encourage and support climate adaptation, notably the UNEP Africa Network on Climate Adaptation which recently convened a large consultation meeting to discuss the structure and scope of the proposed network.

A recent SADC Parliamentary seminar on climate change, water and food security, held in October 2008 concluded that parliamentarians in southern Africa need to take urgent action on climate change, and that they should build on the African and European Parliamentary Action Plan on Climate Change and Food Security which was launched in Kenya in August by the Association of European Parliamentarians for Africa (AWEPA) and the Pan-African Parliament[6]. There is also a Climate working group under COMESA, and various sector-specific activities such as the COMESA/SADC/EAC initiative on climate, agriculture, land-use and livelihoods. The Climate for Development in Africa Programme (ClimDev) is funded by the AU, AfDB and UNECA, but despite having been in planning for several years is still not operational.

A number of international NGOs (like ActionAid, Red Cross, CARE, Oxfam, etc.), in partnership with national and local NGOs, are starting to lobby across the continent on various climate justice issues, and some are already mainstreaming climate adaptation and disaster risk reduction activities into their programmatic work. However, there is a sense that the lack of government leadership and confusing messages coming out of the scientific community are limiting progress on this. NGOs are well placed to support local communities in documenting and voicing concerns about the climate impacts they are already experiencing, their autonomous responses and their demands for adaptation support to their national government and the international community.

A major problem is the concentration of capacity on climate change within too few institutions in Africa. Investment needs to be made in expanding and diversifying the institutions/organisations (governmental, academic, civil society, private, etc.) with the capacity to facilitate adaptation to climate change by rapidly building capacity in existing institutions. Taking advantage of synergies with other resource management and risk reduction efforts (e.g., water, land degradation, biodiversity, coastal zones, health and disasters) is imperative.

Policies and strategic decisions on complex issues such as biofuels, transboundary water management and agrarian reform, in the context of climate change should be backed by reliable scientific guidance. The soundness of African policies will therefore depend, to a large extent, on the scientific community’s ability to provide a solid backing which considers the continent’s diversities and specificities. Effective science communication will be critical to open the required channels between science and policy-making in Africa, and donors constitute an important stakeholder in these dialogues.

Recommendations

  • Monitoring trends in climate and associated environmental changes underpins the identification of vulnerable regions, sectors and groups, and motivates taking serious action on climate change. However, monitoring systems in Africa are incomplete and in many cases degrading through lack of investment. Networks for monitoring climate and environmental changes need urgent strengthening and SIDA could support this working with the Global Climate Observation System.
  • Effective science communication is a key gap which will require long-term dialogue and organisations to 'translate' science into useful forms for policy-makers and other audiences, e.g the media. This is vital if policy is to be based on a clear understanding of the best available science. Efforts on risk communication are currently limited and programmes such as UNITAR's Capacity Development for Adaptation to Climate Change project, which have a risk communication component, could be expanded and sustainable dialogue developed with further funding.
  • There is a clear need to build a body of professional practitioners on climate change adaptation in Africa. This will require going beyond training workshops towards extended training courses incorporating elements from vulnerability assessment to the interpretation of climate scenarios.
  • Strong support for regional networks on climate adaptation is a valuable way of supporting adaptation across Africa. UNEP's incipient Africa network on Adaptation appears to be a good candidate for support, as UNEP is working to strengthen capacity on climate change adaptation, and the network will work through existing regional institutions.

Observed and Projected Changes in Climate by sub-region, summarised from IPCC Fourth Assessment Report

Region Observed Trends Extremes
West - greater warming trend since 1960s (changes not uniform)

- increase in number of warm spells (1961-2000)

- decrease in the number of extremely cold days (1961-2000)

- decline in annual rainfall since end of 1960s (e.g. decrease of 20 to 40% noted between 1968-1990, ), with an increase again since 1990, but still significantly below 1960s levels

-Inter-annual variability has become larger since 1980

- decline in mean annual precipitation of around 4% in tropical rain-forest zone (1960-1998)

Increased incidence of drought 1900-2002
Central - greater warming trend since 1960s (changes not uniform e.g. decadal warming rates of 0.29°C in the African tropical forests)

- declines in mean annual precipitation in the tropical rain-forest zone for period 1960 to 1998 (e.g. around 3% in North Congo and 2% in South Congo)

- 10% increase in annual rainfall along the Guinean coast during the last 30 years

 
East - greater warming trend since 1960s (changes not uniform)

- decreasing trends in temperature from weather stations located close to the coast or to major inland lakes

- intensifying dipole rainfall pattern on the decadal time-scale, characterised by increasing rainfall over the northern sector and declining amounts over the southern sector

 
Southern - greater warming trend since 1960s (changes not uniform e.g. 0.1 to 0.3°C in South Africa)

- increase in number of warm spells (1961-2000)

- decrease in the number of extremely cold days (1961-2000)

- no long-term trend in annual rainfall has been noted, but increased interannual rainfall variability has been observed in the post-1970 period

- in certain parts (e.g. Angola,Namibia,Mozambique,Malawi, Zambia) there is evidence of changes in seasonality

- more intense and widespread droughts reported

- in certain parts (e.g. Angola, Namibia, Mozambique, Malawi, Zambia) a significant increase in heavy rainfall events has been observed associated with flooding

 

 

Region Projections Extremes
West - annual mean surface air temperature for the period 2080-2099 is expected to increase between 3 and 4°C compared with the 1980-1999 period, with less warming in equatorial and coastal areas and greater warming towards the Sahel.

- other experiments indicate higher levels of warming

-There is large model disagreement over changes in precipitation, ranging from a strong drying to a strong wetting. Projections should 'be viewed with caution'

-Some empirical downscaling experiments show a strong drying in the region.

- there is still limited information specific to Africa on extreme events, despite frequent reporting of such events.

-The frequency and intensity of heavy rainfall events is likely to increase

- on a global basis, droughts were also estimated to be slightly more frequent and of much longer duration by the second half of the 21st century relative to the present day

- The intensity of tropical cyclones in the Indian Ocean is likely to increase, but there is little information on changes in frequency or storm tracks.

-The frequency of extremely hot days and seasons will increase.

Central - annual mean surface air temperature for the period 2080-2099 is expected to increase between 3 and 4°C compared with the 1980-1999 period, with less warming in equatorial and coastal areas

- other experiments indicate higher levels of warming

- mean annual rainfall for 2080-2099 is likely to increase in tropical areas (around +7%)

- equatorial regions (north of 10°S and east of 20°E) show an increase in summer (December to February) rainfall

East - annual mean surface air temperature for the period 2080-2099 is expected to increase between 3 and 4°C compared with the 1980-1999 period, with less warming in equatorial and coastal areas

- other experiments indicate higher levels of warming

- mean annual rainfall for 2080-2099 is likely to increase in eastern Africa (around +7%)

- equatorial regions (north of 10°S and east of 20°E) show an increase in summer (December to February) rainfall

- regions located south of 10°S show a decrease in rainfall associated with a decrease in the number of rain days and in the average intensity of rainfall

Southern - annual mean surface air temperature for the period 2080-2099 is expected to increase between 3 and 4°C compared with the 1980-1999 period, with less warming in coastal areas

- other experiments indicate higher levels of warming, up to 7°C for southern Africa in September to November

- Regional Climate Model (RCM) experiments generally give smaller temperature increases, e.g. southern Africa in the 2080s might expect a 3.7°C increase in summer (December to February) mean surface air temperature and a 4°C increase in winter (June to August)

- austral winter (June to August) rainfall will very probably decrease in much of southern Africa, especially in the extreme west (up to 40%)

- regions located south of 10°S show a decrease in rainfall associated with a decrease in the number of rain days and in the average intensity of rainfall

- recent downscaling experiments for South Africa indicate increased summer rainfall over the convective region of the central and eastern plateau and the Drakensberg Mountains

- RCMs indicate a decrease in early summer (October to December) rainfall and an increase in late summer (January to March) rainfall over the eastern parts of southern Africa

 

  1. ↑ Empirical downscaling is a statistical technique to produce station level projections of climate change from global climate models.
  2. ↑ IPCC (2007) Climate Change 2007: Impacts, Adaptation and Vulnerability, Africa. Geneva: IPCC, page 435.
  3. ↑ UNEP (2007) Post-Conflict report on Darfur
  4. ↑ UNEP (2009) From Conflict to Peace-building: the role of natural resources and the environment.
  5. ↑ AMCEN (2008) Climate Change Adaptation in Africa: Scoping paper for the Expert Group Meeting. See http://www.unep.org/roa/Amcen/Amcen_Events/12th_Session_AMCEN/docs/reference/ScopingPaper-ClimateChange.pdf
  6. ↑ AWEPA Press release 2008