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Michael E. Meadows: Global Change and Southern Africa
Global Change and Southern Africa
MICHAEL E. MEADOWS
Department of Environmental and Geographical Science, University of Cape Town, Private Bag X3,
Rondebosch 7701, South Africa. Email: [email protected]
Received 12 July 2005; Revised 25 October 2005; Accepted 15 December 2005
Abstract
The developing nations of southern Africa have previously been identified as
vulnerable to the vagaries of global change, particularly in terms of future climate
change. This paper explores recent climate change scenarios for the region in
terms of some representative sectors of the environment-society interface, namely
biodiversity, agriculture and related land uses, water resources and health issues.
It is concluded that the impacts of predicted climate changes over the next century
are likely to be very marked indeed. Biome distribution, agriculture, rangelands
and water resources are highlighted as being negatively impacted in ways that
will increase the vulnerability of the great majority of the region’s population to
natural hazards. The potential impact of these changes on the prolific biodiversity of southern Africa is clear. Holistic policy responses, incorporating both
environmental and human development concerns, are required in the near future
if a crisis is to be averted.
KEY WORDS Climate change; impacts; biodiversity; agriculture; water
resources; health
Introduction
It is clear from previous studies that southern
Africa faces significant environmental and
economic challenges as a consequence of global
climate change (Magadza, 1994; Hulme, 1996).
In the decade since the publication of Hulme’s
1996 review, new – more highly resolved – climate change scenarios have emerged (for example, IPCC, 2001) that suggest these and, indeed,
other African countries remain vulnerable to the
vagaries of a rapidly changing environment, more
especially against the background of a global
economy that continues to marginalise developing
nations (Halsnaes et al., 2002). As Adger et al.
(2005) note, there have been key developments
during recent years in respect of the interaction
between global changes and human societal
responses. These include a more sophisticated
(although admittedly still limited) understanding
of the dynamics of the earth system coupled
with a greatly expanded available data set. The
emergence of a greater diversity of social science
perspectives on global change is also important,
in particular the recognition of complexity in terms
of vulnerability, resilience, resistance and the
diversity of the human response (Adger et al.,
2005). In part due to their level of vulnerability
and in part due to the high proportion of the
global population that they house, developing
countries as a whole have been an important focus
of global change impact studies (Ravindranath
and Sathaye, 2002; Markandya and Halsnaes,
2004) although, with the notable exception of
South Africa, those in southern Africa have
enjoyed relatively little attention in this regard.
Global climate change is a critical issue, both
in Africa in general and in southern Africa
(Desanker and Justice, 2001). It is timely, then,
that the situation in the region be reviewed in
light of the latest available climate change scenarios. This paper aims briefly to review the scenarios and then goes on to explore the responses
of some key elements of the environmental and
economic systems in southern Africa. In particular,
the paper focuses on the first-order implications
of recent and predicted future climate change
Geographical Research • June 2006 • 44(2):135–145
doi: 10.1111/j.1745-5871.2006.00375.x
Geographical Research • June 2006 • 44(2):135–145
136
for four important sectors: ecosystems and biodiversity; forestry, agriculture and rangelands;
water resources, and health issues. This is not a
comprehensive list for it does not include all
elements of the environment-society interface,
for example possible impacts on marine ecosystems and fisheries; but it is representative of the
range of sectors and likely impacts in the region.
‘Global change’ here is interpreted mainly as
predicted climate change over the next 50 years
or so, together with its associated environmental
variables, rather than economic changes such as
globalisation, although issues related to such
processes are highlighted where relevant.
For the purposes of this paper, southern Africa
is defined as the geographical area encompassed
by the countries of Namibia, Botswana, Zimbabwe,
Mozambique, South Africa, Lesotho and Swaziland (Figure 1). Examples are drawn from across
the region where possible, although relevant
studies from outside South Africa are still few in
number. Nevertheless, South Africa itself has
examples of all the regional ecosystem types
and, despite its relative wealth and unusual
juxtaposition of developed and developing economies within one country, is sufficiently representative of the region to suggest that the
responses to change are relevant beyond its
Figure 1
borders. Moreover, South Africa has completed
a recent ‘country study’ on the potential effects
of climate change (DEAT, 2000), although this
was not referred to in Smith and Lazo’s (2001)
global review of such studies.
Climate change scenarios
Globally, climate change scenarios rely on the
application of General Circulation Models (GCMs),
principally to a so-called ‘doubled CO2’ situation. Initially, such models were at a very coarse
scale of spatial resolution and failed to couple
the ocean and atmosphere systems. More recently,
however, there have been significant developments
in the number and complexity of global climate
parameters handled by the models, and there is
now greater confidence that they can produce
valid scenarios for conditions under perturbed
atmospheric chemistry and land cover situations
(Houghton, 2004). Due to restrictions in computer
power, outputs even of these more skilful GCMs
remain only at a grid size of around 300 km ×
300 km, and as such they have limited application to predictions of impacts at a scale that
allows for meaningful policy response. All such
models reveal positive mean annual temperature
anomalies in the future, in the range of two to
three degrees Celsius for southern Africa.
Map of southern Africa showing localities mentioned in the text.
© 2006 Institute of Australian Geographers
Michael E. Meadows: Global Change and Southern Africa
Precipitation, in terms of mean annual amounts,
seasonality and length and intensity of wet/dry
seasons is, however, a more cryptic parameter.
Hulme’s (1996) assessment was based on models with a grid size of 0.5° latitude by longitude
and suggested generally drier climates with
increased rainfall variability across southern Africa.
The third assessment report of the International
Panel for Climate Change (IPCC, 2001) based
its predictions on models with a similar spatial
resolution, although the outputs were more
sophisticated in their use of several different
emission scenarios. Again there is consensus on
significant climate warming as an outcome,
increases in the severity of flood events and, for
southeastern Africa at least, reduction in mean
annual precipitation (Hulme et al., 2001).
The advent of regional climate models (RCMs)
employing statistical downscaling (Cavazos and
Hewitson, 2005) to produce outputs with a grid
size of 50 km × 50 km or less has facilitated
application of model predictions at a geographical scale more useful at the policy-response
level. The most recent scenarios (Hewitson and
Crane, 2005) are derived from three GCMs:
HadCM3, ECHAM4.5 and CSIRO Mk2. Given
that temperature warming per se (of the order of
two to three degrees Celsius) is widely predicted
and uncontentious, the models instead employ
statistical downscaling to focus on scenarios of
rainfall in particular. The outputs are for South
Africa only, but are certainly relevant to and
indicative of the nature and scale of precipitation changes in the region in general. The GCMs
produce a spatially cohesive set of predicted
changes and converge on a downscaled solution
that suggests a) increased summer rainfall in the
eastern part of South Africa and the interior, and
b) reductions in winter rainfall in the Western
Cape.
Typical model outputs (Hewitson and Crane,
2005) suggest increases in mean annual rainfall
(in places anomalies exceed 100 mm) over the
convective regions of the eastern and central
plateau and the Drakensberg Mountains, while a
reduction in rainfall is predicted for those parts
of the sub-continent under the influence of winter frontal systems (Hewitson and Crane, 2005).
The scenarios go beyond simple predictions of
mean annual precipitation anomalies and also
suggest an increase in the frequency of heavy
(greater than 20 mm per day) rainfall events.
According to one of the models explored
(ECHAM), some areas in the eastern part of the
region would experience an additional two days
© 2006 Institute of Australian Geographers
137
per month of heavy rain (Figure 2); tangible
evidence that most GCMs forecast an increase
in the frequency and magnitude of extreme
events under elevated greenhouse gas concentrations. That such changes are already underway
is a contention supported by the work of Mason
et al. (1999), who analysed historical rainfall
data for southern Africa and noted an increase in
the intensity of extreme rainfall events for 1931–
1960 and a further increase from 1961–1990 over
70% of South Africa. Regionally downscaled
models further indicate variations in the number
of raindays per month and in some instances a
decrease in this parameter coinciding with an
increase in mean annual rainfall and the frequency of heavy rain days, all of which point to
climate scenarios that are significantly more
dynamic and variable than those of the present day.
Further advances in the ability of such models
to skilfully predict future climates are anticipated,
although the dynamics and influence of changes
in the El Niño Southern Oscillation (ENSO) are
a key challenge (Hulme et al., 2001; Mason,
2001). Indeed, there remain significant limitations in the predictive ability of downscaled circulation models. For example, changes in the
frequency and magnitude of important synoptic
events such as tropical or extra-tropical cyclones
are difficult to predict (Hudson and Hewitson,
1997; Sinclair et al., 1997; Henderson-Sellers
et al., 1998; Jury et al., 1999). Recent advances
(see Landman et al., 2005) show that regional
models can produce cyclone-like vortices and further iterations may soon provide more realistic
simulations of tropical storm genesis. Such
analyses may in time show how global climate
change may influence the genesis of these systems in the southwestern Indian Ocean (Landman et al., 2005) but, for now, the general
conclusion reached by Henderson-Sellers et al.
(1998), that tropical cyclones are not expected
to change significantly with global warming,
needs to be accepted for southern Africa.
Impacts of climate change on ecosystems and
biodiversity
Given that southern Africa contains two of the
world’s top 25 so-called ‘hotspots’ (Myers et al.,
2000), it is hardly surprising that considerable
research effort has been expended in assessing
the possible impacts of global climate change on
biodiversity in the region. The South African
Country Report on Climate Change commissioned
by the Department of Environment Affairs and
Tourism (DEAT, 2000) has three chapters devoted
138
Figure 2 Projected climate change anomaly of heavy rainfall
events (raindays >20 mm) per month for summer (DJF)
derived from the downscaled daily precipitation from the
ECHAM model (from Hewitson and Crane, 2005). The darker
shaded areas can expect more than two additional heavy rain
days during this summer period.
to the issue of impacts of change on plant, animal
and marine diversity respectively. Rutherford
et al. (in DEAT, 2000) suggest that projected
climate changes on the basis of the HADCM2
model are sufficient to reduce the area suitable
to South African biomes to perhaps only one half
of their current spatial distribution (Figure 3).
Significant reductions in such areas are modelled
to occur in the western, central and northern
parts and include the almost total displacement
of the existing Succulent Karoo Biome and a
marked eastward relocation of the Nama-Karoo
Biome (Rutherford et al. in DEAT, 2000; Hannah
et al., 2002). They go on to suggest the constriction of the Savanna Biome on the Botswana and
Zimbabwe borders. The prolific plant species
richness of the Fynbos Biome in the southwest
is markedly threatened (Midgely et al., 2002),
an indication being the loss of around 10% of all
members of the Proteaceae family. Associated
reductions in the ranges of individual species are
likely to alter community composition and
produce major vegetation structural changes in
the Grassland Biome where there are significant
threats from invading savanna tree species
(Rutherford et al., in DEAT, 2000). Further
iterations of the climate envelope models used
in developing these scenarios reveal a power-law
relationship with geographical range size and
Geographical Research • June 2006 • 44(2):135–145
the resultant ‘doomsday’ scenario that up to
37% of taxa in a selection of species-rich areas
(including southern Africa) are ‘committed to
extinction’ (Thomas et al., 2004, 145). In nearly
all biomes of southern Africa, invasive alien
species are likely to be advantaged by changed
climates and increased atmospheric carbon dioxide
concentrations (Dukes and Mooney, 1999) in a
region that is already strongly impacted by such
species and which stands to be further transformed by agriculture and urbanisation in the
future (Rouget et al., 2003).
This rather depressing tale is repeated and
even amplified when animal taxa are considered
(van Jaarsveld et al., in DEAT, 2000). Applying
a similar climate envelope technique to that
employed in the plant diversity impact analysis,
Erasmus et al. (2002) demonstrate significant
range contraction in almost 80% of the 179 species included in the study (including 34 bird, 19
mammal, 50 reptile, 15 butterfly and 57 ‘other
invertebrate’ species), with the majority of these
contractions being towards the east. Most
chillingly, perhaps, the authors suggest that the
flagship conservation area in the region, South
Africa’s Kruger National Park, may lose up to
66% of those animal species included in the
analysis. Clearly this kind of analysis points to
the imperative of understanding the role of climate
change in relation to the network of conservation areas in southern Africa and prompts the
need for considering the further development of
so-called trans-frontier parks and corridors linking such areas.
Impacts of climate change on agriculture,
rangelands and forestry
Agriculture
In most countries in southern Africa, agriculture
(mostly, but not exclusively, of the subsistence
form) is the dominant mode of individual economic activity and is a leading component of the
national economies in all cases. The staple food
in many instances is maize, and this prompted
du Toit et al. (in DEAT, 2000) to explore the
predicted impacts of climate change on the productivity of this crop in particular. Depending
on which particular scenario is employed, maize
production will either be only marginally
affected by the year 2050 in southern Africa or
show negative anomalies of up to 20%, the
uncertainty being a product of the extent to
which the crop will benefit from the carbon
dioxide fertilisation effect (not yet quantified
© 2006 Institute of Australian Geographers
Michael E. Meadows: Global Change and Southern Africa
139
Figure 3 Hannah et al.’s (2002) models of distribution of South African biomes under contemporary climates (a), and the
HadCM2 model applied to an atmosphere with 550 ppm carbon dioxide (b). Unshaded areas in (b) represent areas with
climatic conditions not currently encountered so that it is not possible to predict the composition of the communities in
these places.
© 2006 Institute of Australian Geographers
140
under southern African conditions (Turpie et al.,
2002)). At a broader spatial scale, Jones and
Thornton (2003) predict a 10% reduction in
maize productivity in Africa, although this average figure hides very marked spatial variability.
In any case, maize production in the region
oscillates strongly on an annual basis with varying weather conditions and the more marginal
western production areas in the region may well
become unsuitable for maize in the future
(Turpie et al., 2002). The South African Country
Study (DEAT, 2000) concludes that, overall,
despite increases in carbon dioxide and possible
increased precipitation in some of the summer
rainfall areas, reduced maize productivity could
result in economic losses of hundreds of millions
of Rands.
For the major commercial crops in the region,
for example, wheat and sugar cane, Turpie et al.’s
so-called ‘back-of-the-envelope’ calculations
suggest losses of 10 to 20% by 2050. Furthermore, changes in soil moisture, which are often
inadequately parameterised in GCMs, both as an
output of and as an influence on climate change
(see New et al., 2003), due to the anticipated
increased regional temperatures are a potential
additional challenge for agriculture. Overall, the
threats to the agricultural sector of the southern
African economy are very marked and, as noted
by Leichenko and O’Brien (2002), there are
further constraints that arise from economic
globalisation, particularly for marginalised subsistence farmers in the region.
Rangelands
Of the total land area of South Africa, almost
70% is classified as grazing land (NDA, 2000)
and this figure may be taken as representative
of the region as a whole. Livestock production
within such areas is clearly dependent on the
productivity of the associated vegetation of these
rangelands. Turpie et al. (2002) explore the
impacts of climate change on animal production
in South Africa and conclude strong spatial
variability in the scale and direction of the
effect. For example, productivity in the savanna
grasslands in the eastern parts of the country
may well improve, especially if the carbon dioxide fertilisation effect is taken into account,
although it may well manifest itself as bush
encroachment. In general the impact of change
is likely to be strongly negative in the sheeprearing areas of the arid and semi-arid west, and
marginally to quite strongly positive in the larger,
livestock-rearing areas of the better watered east
Geographical Research • June 2006 • 44(2):135–145
(Turpie et al., 2002). Problems identified in the
more arid parts of the region are consistent with
the global analysis of drylands performed by
Puigdefabregas (1998), who notes the sensitivity
of such systems to disturbance and the likelihood of enhanced land degradation as a consequence. Oba et al. (2001) have demonstrated the
significance of external climate forcing ENSO,
in the case of sub-Saharan Africa, in promoting
desertification, and Meadows and Hoffman (2003)
concur that degradation of rangelands is likely
to accelerate under scenarios of global climate
change in the subsistence grazing areas of the
former so-called homelands of South Africa.
Using an established model of dune mobility,
Thomas et al. (2005) explore the impact of
climate change scenarios on the extensive,
vegetated, linear dune systems of the Kalahari.
Although no account is taken of the possible
carbon dioxide fertilisation effect, the modelling
results suggest future widespread remobilisation
of these dune systems throughout the year with
consequent very severe implications for rangeland productivity in the region (Figure 4). Previous
considerations of the impact of climate change
on southern African drylands may, therefore,
have underestimated the extent of future pastoral
and agricultural disruption due to global change.
Forestry
Although plantation forests, much of them Stateowned, only account for just over 1% of the land
area of South Africa (regionally, the value is
likely to be somewhat lower), these make a
significant contribution to the national economy
and are an important focus in the Country Study
(DEAT, 2000) and subsequent commentaries
(Turpie et al., 2002). Although carbon dioxide
fertilisation is difficult to quantify for individual
commercial tree species, it appears that any
beneficial effect will be strongly outweighed by
enforced range changes and the reduction in areas
classified as ‘highly suitable’ (Turpie et al., 2002),
especially in the case of eucalypts. Nevertheless,
this conclusion is based on earlier climate change
scenarios and on the general premise that southern African climates will generally aridify by
2050, whereas the latest regionally downscaled
scenarios (Hewitson and Crane, 2005) suggest
that this may not necessarily be the case in the
eastern parts where many of the plantations are
located. Coupled with a fertilisation effect due
to changes in atmospheric chemistry, the response
of forestry may be somewhat more positive than
previously thought.
© 2006 Institute of Australian Geographers
Michael E. Meadows: Global Change and Southern Africa
141
Figure 4 Predicted three-month dry season (August, September, October) dunefield activity after 2070. The shaded blocks
represent grid squares for which climate model-generated predicted changes in rainfall and wind characteristics result in
aeolian activity on the crest (dark grey), flank (grey) and interdune (light grey) of dunes that are currently inactive. This is
modelled as the mean of HadCM3 runs using IS92a, A2, A1fa and B2 emission scenarios. Redrawn after Thomas et al. (2005).
Impacts of climate change on water resources
Southern Africa is fundamentally an arid subcontinent, more especially in the interior and
western parts, so that most ecological – and, for
that matter, economic – processes are, to a
greater or lesser extent, limited by water availability. Schulze (2000) documents the challenges
of predicting the hydrological response to climate change in situations, such as those which
prevail across much of the region, where the
coefficient of variation of runoff is already very
high. In other words, the hydrological regime is
© 2006 Institute of Australian Geographers
so variable in space and time, that trends imposed
by climate change are very difficult to detect.
Nevertheless, Schulze (2000) goes on to estimate
anomalies in mean annual runoff employing the
UKMO model and a so-called IS92a emission
scenario for the year 2050, and demonstrates
marked runoff reductions in the already xeric
western parts of southern Africa. Arnell (1999)
employs Hadley Centre models HadCM2 and
HadCM3 to predict changes in runoff in the
major river basins of southern Africa by 2050.
The models suggest substantial runoff reduction
142
in the Zambezi (− 40%), Limpopo (−30%) and
Orange (−5%) basins as well as decreases in the
volumes of low flows in all three rivers (Arnell,
1999). Such impacts are likely to be exacerbated
by change in land use, which is an important
component of the hydrological system.
Further stresses on the hydrological system
arise from increased demand. Across the region
there is a political and practical imperative to
improve access to potable water for both the
rural and urban poor in particular, placing great
strain on a resource that is already stretched due
to high agricultural and industrial requirements
(Schulze et al., 2001). Meigh et al. (1999) conclusively demonstrate the likelihood of increases
in water scarcity in large parts of eastern and
southern Africa as a result of the combined
effects of reduced groundwater recharge and
elevated demand. For the winter rainfall zone of
the south-western Cape, a region characterised
by strong population growth and accelerated
economic development in the recent past, New
(2002) shows how reduced streamflow response
in the future, together with elevated water demand
against a limited supply capacity, will soon
result in the permanent inability to meet supply
yields in the area’s largest city (Cape Town).
The South African Country Study report (DEAT,
2000) bases its hydrological predictions of
climate change on two GCMs (HADCM2 and
CSM), which both point to a greater intensity of
rainfall events in the eastern part of southern
Africa (consistent with Hewitson and Crane’s
(2005) regionally downscaled model outputs) and
accentuated flooding in the associated rivers.
This positive effect on runoff, however, is offset
by longer dry spells and, in short, a significantly
more variable hydrological response. Geomorphic
implications may include increased soil erosion,
and Meadows and Hoffman (2003) have indicated as much for parts of the summer rainfall
region. All of this points to a potentially increased
hydrological hazard in the future, both in terms
of drought and flood frequency and intensity.
Coupled with possible negative changes in water
quality due to increased temperatures, the scenario
is especially gloomy unless there are significant
shifts in policy vision (Mukheiber and Sparks,
2003).
Impacts of climate change on health
A large proportion of the population of the
developing countries in southern Africa is vulnerable to the diseases of poverty, for example
malaria, tuberculosis and, increasingly, HIV/AIDS.
Geographical Research • June 2006 • 44(2):135–145
Despite the intuitively logical view that rapid
climate change should negatively influence human
health, especially in the developing world, the
first conclusively documented evidence of such
effects was published only recently when
Rodó et al. (2002) demonstrated the relationship
between the incidence of cholera and varying
ENSO-related weather phenomena in Bangladesh. Nevertheless, epidemiologists have been
aware for some time of the potential impact of
such changes on diseases and disease vectors,
especially in the case of malaria. Van Lieshout
et al. (2004) model the potential impact of
changed climate (using four of the emission scenarios from IPCC, 2001) and show that much of
sub-Saharan Africa is likely to experience conditions more conducive to the transmission of
malaria in the future, with up to 60 million more
people at greater risk. However, most of these
people live in East Africa, and parts of southern
Africa may become too warm and dry to sustain
the vector organisms (mosquitoes). Certainly,
regional warming is associated with a resurgence in the disease (Patz, 2002). According to
the World Health Organisation, malaria-related
deaths in children doubled in many parts of
Africa between the 1980s and 1990s and already
account for 20% of childhood mortality on the
continent (Hales and Woodward, 2003).
Potential changes in the prevalence of HIV/
AIDS have not thus far been assessed, although
the virus is opportunistic and is likely to increase
in the event of the intensification of other
climate-related stressors, such as reduced food
security, on vulnerable populations. Health
policies in countries of southern Africa therefore
need to be based on the recognition of possible
increased risk of HIV/AIDS prevalence in a
region which already has the highest incidence
in the world (Plot et al., 2001).
Conclusions
It is pertinent to compare the predicted responses
of the natural and associated economic systems
reviewed here with those identified by Hulme in
1996. There are many similarities in the picture
that emerges, but some key differences. Hulme’s
original review noted a marked concern for
future losses of biodiversity in response to range
shifts under both climate scenarios considered.
By comparison, the regional analysis documented
in Hannah et al. (2002), based mainly on the
IPCC (2001) scenarios, suggests much greater
impact, with very substantial areas of southern
Africa developing climatic conditions for which
© 2006 Institute of Australian Geographers
Michael E. Meadows: Global Change and Southern Africa
there is no meaningful modern analogue. Accordingly, while it is difficult to be precise as to what
particular mix of species will prevail in such areas
if these scenarios come about, it is clear that
biodiversity losses could be very severe indeed.
Reduction in diversity of grazing mammals was
identified in the Hulme study, but Erasmus and
co-workers (2002) make a compelling case for
accentuated impacts across a wide range of animal
taxa, with consequent increased levels of conflict between conservation and other land uses.
Hulme’s report highlighted agricultural impacts
but suggested that not all the changes would
have negative consequences. Maize yields, for
example, were expected to increase, although
Jones and Thornton’s (2003) considerations predict substantial reductions. Hulme’s review also
appears to underestimate the regional impacts of
climate change in rangelands, more particularly
in light of Thomas et al.’s (2005) suggestion of
widespread remobilisation of sand across large
areas of southern Africa.
The most recent, regionally-downscaled, climate change scenarios provide improved spatial
resolution and open the door for more precise
estimates of the impact of such change on runoff. These scenarios are consistent with those
developed by Hulme in predicting reduced
rainfall-runoff ratios in the western and westerncentral parts of the region and in suggesting
increased variability elsewhere. This hydrological
response will, of course, be an important driver
of changes in other sectors too, not least in agriculture and for the management of industrial and
urban water supplies. Finally, with respect to
health issues, subsequent reviews of the implications of climate change for diseases such as
malaria concur with Hulme’s analysis of the situation in anticipating an increase in prevalence.
For other prominent diseases of southern Africa,
such as HIV/AIDS, scientists have yet to assess
the second-order impacts of future climate change,
and this must become an important consideration
of health and welfare planning for governments.
By comparison with the scenarios developed
and modelled by Hulme (1996), more recently
available, downscaled scenarios point to accentuated, and probably accelerated, problems in
relation to all sectors explored in this paper.
Fundamentally, this means that the vast majority
of the southern African population, the rural and
urban poor, have an increased level of vulnerability to impacts. As Misselhorn (2004) notes,
enhanced levels of vulnerability are already deeply
embedded and manifest themselves as widespread
© 2006 Institute of Australian Geographers
143
food insecurity across the region, especially in
the less developed countries of Mozambique,
Lesotho, Swaziland, Namibia and Zimbabwe,
although it is difficult to develop policy given
the uncertainties about the nature and direction
of change (Schneider and Kuntz-Duriseti, 2002).
Without doubt, however, global change, with all
its complex manifestations, will only serve to
further marginalise those most at risk to natural
hazards such as floods and droughts. What is
clearly needed is recognition of the potential
problems, and development and implementation
of holistic mitigatory policies that address both
biodiversity conservation and livelihood concerns.
For southern Africa, global change is a major
threat to the survival of its communities, human
and otherwise.
ACKNOWLEDGMENTS
The author wishes to record his appreciation to two referees for their advice in helping to improve the content of this
paper and to Anne Westoby for drafting the figures.
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