Download Summary Working Group II Contribution to the Fifth - ClimDev

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts

Environmental determinism wikipedia , lookup

Transcript
Summary
Working Group II Contribution to the Fifth Assessment
Report of the Intergovernmental Panel on Climate
Change: Impacts, Adaptation and Vulnerability
21st century, with the increases being experienced
in the tropics, especially tropical West Africa, at
Temperature: Near surface temperatures have least one or two decades before the global average.
increased by 0.5°C or more during the last 50 to High rates of warming are also projected to occur
100 years over most parts of Africa. Since the 1980s in the semi-arid areas of southwestern Africa,
significant increases in temperature have been including northwestern South Africa, Botswana
experienced in the equatorial and southern areas and Namibia (IPCC, 2014b).
of eastern Africa while in recent decades annual
mean, maximum and minimum temperatures have Development: Climate change may hinder
increased over much of southern Africa (IPCC, progress in attaining the MDGs, which will in
turn reduce the resilience and adaptive capacity of
2014b).
individuals, households, communities and states in
Precipitation: In much of Africa there is a lack of Africa (IPCC, 2014b).
sufficient observational data to draw conclusions
about trends in annual precipitation. However, Agriculture: The main economic activity (in terms
there have very likely been decreases in annual of employment) in Africa, agriculture is highly
precipitation over the past century in parts of the vulnerable to the impacts of climate change.
western and eastern Sahel and increases in parts Subsistence agriculture will be most greatly
affected, the cascading impacts of which will
of eastern and southern Africa (IPCC, 2014b).
have a gender dimension. In sub-Saharan Africa
84 percent of women versus 69.5 percent of men
Vulnerability and impacts in Africa
are engaged in subsistence agriculture. Climate
change will very likely negatively affect yields of
The impacts of climate change are projected (with
major cereal crops across Africa. Among the most
medium confidence) to impede economic growth
vulnerable are maize-based systems, particularly
and efforts to reduce poverty, erode food security,
those in southern Africa. It is estimated that by
prolong existing poverty traps and create new ones.
2050 yield losses could be 18 percent for southern
It is projected that temperatures in Africa will
Africa, 22 percent across sub-Saharan Africa and
rise faster than the global average increase in the
over 30 percent in South Africa and Zimbabwe.
Observed trends in Africa
http://www.uneca.org/acpc
Predicted yield losses (dependent on climate
scenarios) vary from 2 percent for sorghum to 35
percent for wheat by 2050 under an A2 scenario.1
Parts of the continent that are prone to drought
are at a high risk of livestock loss. Regions that
are projected to become drier with climate change,
such as northern and southern Africa, are of
particular concern. Adequate provision of water
for livestock production could become more
difficult under climate change. For example, the
cost of supplying livestock water from boreholes
in Botswana will increase by 23 percent by 2050
under an A2 scenario due to increased hours of
groundwater pumping needed to meet livestock
water demands under warmer and drier conditions.
While adaptation will help manage the risk from
climate change in the near term, in the long-term
agriculture in Africa will face significant challenges
to adaptation (IPCC, 2014b).
Food security: Rising food prices have been blamed
for the additional deaths from malnutrition of
30,000 to 50,000 children. Climate change could
play a role in further increasing the price of basic
cereals, which would significantly affect food
security in Africa. In the period 2010 to 2012 an
estimated 26.8 percent of sub-Saharan Africans
were undernourished (IPCC, 2014a).
Coastal systems: One quarter of Africa’s population
lives within 100 km of the coast and half live in
coastal zones, which will be significantly affected
1
Six scenarios (A1B, A1T, A1F1, A2, B1 and B2) drawn from four
families (A1, A2, B1 and B2) were created from four Integrated Assessment
Models (IAMs) for the IPCC’s Special Report on Emissions Scenarios. The scenarios represented different socio-economic contexts but do not include mitigation options. The A1 storyline and scenario family describes a future world of
very rapid economic growth, global population that peaks in mid-century and
declines thereafter, and the rapid introduction of new and more efficient technologies. The A2 storyline and scenario family describes a very heterogeneous
world. The underlying theme is self-reliance and preservation of local identities. Fertility patterns across regions converge very slowly, which results in
continuously increasing global population. Economic development is primarily
regionally oriented and per capita economic growth and technological change are
more fragmented and slower than in other storylines. The B1 storyline and scenario family describes a convergent world with the same global population that
peaks in midcentury and declines thereafter, as in the A1 storyline, but with rapid
changes in economic structures toward a service and information economy, with
reductions in material intensity, and the introduction of clean and resource-efficient technologies. The emphasis is on global solutions to economic, social, and
environmental sustainability, including improved equity, but without additional
climate initiatives. The B2 storyline and scenario family describes a world in
which the emphasis is on local solutions to economic, social and environmental
sustainability. It is a world with continuously increasing global population at a
rate lower than A2, intermediate levels of economic development, and less rapid
and more diverse technological change than in the B1 and A1 storylines. While
the scenario is also oriented toward environmental protection and social equity, it
focuses on local and regional levels (IPCC, 2000).
2
http://www.uneca.org/acpc
by rising sea levels and storm surges. In Durban
in 2007 a 14 metre swell, the result of high winds
generated by a cyclone and an extremely high tide
caused an estimated USD 100 million in losses
and damages. In Tanzania it is estimated that
under a low emission scenario (B1) 3,579 to
7,624 km2 of land would be lost with 234,000 to
1.6 million people per year affected by flooding.
Without adaptation it is estimated that losses
and damage would be between USD 26 million
and 55 million per year. In Kenya coastal flooding
due to sea level rise will affect 10,000 to 86,000
people, with losses and damages estimated at
between USD 7 million and 58 million (IPCC,
2014b).
Ocean systems: Ocean acidification has lowered
reef productivity and resilience and has significant
consequences for reef biodiversity, ecology and
ecosystems. Fisheries in Africa are an important
source of food security, providing one-third
of the protein intake of Africans. In Africa
fisheries depend on either coral reefs (east coast)
or coastal upwelling (west coast), both of which
will be affected by climate change through ocean
acidification, rise in sea surface temperatures and
changes in upwelling. Fisheries in the coastal
countries of West Africa will be the most affected
by climate change. By 2050 it is projected (under
an A1B scenario) that the value of fish caught
could decline by 21 percent, resulting in a loss to
the region’s economy of USD 311 million and a
loss of fisheries-related employment of 50 percent
(IPCC, 2014b).
Water resources: Climate change will contribute
to a decrease in the availability of water in
southern and northern Africa. All countries
within the Zambezi River Basin could experience
significant water shortages (IPCC, 2014b).
Adaptation in Africa
Though there has been progress on managing
the risks posed by climate variability and nearterm climate change to food production current
adaptation measures will be insufficient to
address the long-term impacts of climate
change. Research on the constraints to adaptive
capacity is beginning to indicate where the limits
to adaptation might lie in parts of Africa (medium
confidence). Combined with other stressors,
climate change may overwhelm the ability
of people and households to cope and adapt.
Efforts to reduce vulnerability, build resilience
and implement adaptation strategies are also
constrained by a wide range of data and research
gaps including data management and monitoring
of climate parameters, the development of climate
change scenarios, monitoring systems, research
and methodologies to assess and quantify the
impacts of climate change on different sectors.
A lack of sufficient resources for adaptation
continues to be a barrier to adaptation. In 2012
USD 350 million was provided for mitigation
activities while USD 14 billion was provided for
adaptation activities, approximately 30 percent
of which went to Africa (IPCC, 2014b).
Addressing climate risks, building adaptive
capacity and implementing adaptation strategies
will require significant financial resources and
technological support. In a 2°C world even with
high levels of adaptation, there could be very
high levels of risk for Africa. In a 4°C world food
security will be severely jeopardized throughout
the continent and adaptation will have limited
potential for reducing risk (IPCC, 2014b).
References:
IPCC (2000) Summary for Policymakers.
Emissions Scenarios: A Special Report of IPCC
Working Group II. Cambridge and New York:
Cambridge University Press.
IPCC (2014a) Chapter 7: Food Security and
Food Production Systems. Climate Change 2014:
Impacts, Adaptation and Vulnerability, Contribution
of Working Group II to the Fifth Assessment Report
of the Intergovernmental Panel on Climate Change.
Cambridge and New York: Cambridge University
Press.
IPCC (2014b) Chapter 22: Africa. Climate
Change 2014: Impacts, Adaptation and Vulnerability,
Contribution of Working Group II to the Fifth
Assessment Report of the Intergovernmental Panel
on Climate Change. Cambridge and New York:
Cambridge University Press.
IPCC (2014c) Summary for Policymakers.
Climate Change 2014: Impacts, Adaptation and
Vulnerability, Contribution of Working Group II to
the Fifth Assessment Report of the Intergovernmental
Panel on Climate Change. Cambridge and New
York: Cambridge University Press.
http://www.uneca.org/acpc
3
4
http://www.uneca.org/acpc