The summary presents key findings from the IPCC AR5 Synthesis Report:
- Human activity, primarily greenhouse gas emissions, have been the dominant cause of global warming since the mid-20th century.
- If emissions continue at a high rate, temperatures could increase more than 2°C by mid-century, causing severe impacts.
- Options exist to limit warming to 2°C through substantial reductions in greenhouse gases, but the window for action is closing rapidly as the carbon budget is being used up.
- Impacts are already apparent across Africa through increased temperatures, altered precipitation patterns, and effects on agriculture, water resources and ecosystems. Future impacts are expected to be substantial without adaptation and mitigation efforts.
1. IPCC AR5 Synthesis Report
Presentation of the IPCC Fifth
Assessment Report
23rd February
Key Messages of the IPCC AR5
Nairobi, Kenya
2. Key Messages
➜ Human influence on the climate system is clear
➜ The more we disrupt our climate, the more we
risk severe, pervasive and irreversible impacts
➜ We have the means to limit climate change and
build a more prosperous, sustainable future
AR5 WGI SPM, AR5 WGII SPM, AR5 WGIII SPM
3. Oceans absorb most of the heat
➜ More than 90% of the
energy accumulating
in the climate system
between 1971 and
2010 has
accumulated in the
ocean
➜ Land temperatures
remain at historic
highs while ocean
temperatures
continue to climb AR5 SYR
4. It is extremely likely that human influence has been the dominant
cause of warming since the mid-20th century
AR5 SYR SPM
5. • Surface temperatures have
increased by 0.5°C or more
during the last 50-100 years over
most parts of Africa.
• Surface temperature anomalies in
Africa were significantly higher for
the period 1995–2010 compared to
the period 1979–1994.
• Increase in seasonal mean
temperature in many areas of
Ethiopia, Kenya, South Sudan, and
Uganda over the last 50 years.
Evidence of warming over land regions across Africa, consistent with
anthropogenic climate change, has increased
AR5 WGII
8. Anthropogenic GHG emissions have increased since the pre-industrial era, driven
largely by economic and population growth, and are now higher than ever.
AR5 WGIII SPM
The atmospheric concentrations of carbon dioxide, methane and nitrous
oxide that are unprecedented in at least the last 800,000 years.
9. Sources of emissions
Energy production remains the primary driver of GHG emissions
35%
24% 21% 14%
6.4%
2010 GHG emissions
Energy Sector
Agriculture,
forests and
other land uses
Industry Transport
Building
Sector
AR5 WGIII SPM
10. AR5 WGII Fig 22-3 (a) Confidence in detection and in attribution of observed climate change over
Africa to anthropogenic emissions. (b) Confidence in detection and in attribution of the impacts of
observed regional climate change on various African systems.
11. Some of the changes in extreme weather and climate events
observed since about 1950 have been linked to human influence
AR5 WGI SPM
Impacts are already
underway in a number of
regions:
• decrease in cold
temperature extremes
• increase in warm
temperature extremes
• increase in extreme
high sea levels
• increase in the number
of heavy precipitation
events
12. Projected climate changes
Continued emissions of greenhouse gases will cause further
warming and changes in the climate system
Global glacier volume will
further decrease
Global mean sea level will
continue to rise during the
21st century
It is very likely that the Arctic sea
ice cover will continue to shrink
and thin as global mean surface
temperature rises
Oceans will continue to warm
during the 21st century
AR5 WGI SPM
13. Potential Impacts of Climate Change
Food and water shortages
Increased poverty
Increased displacement of
people
Coastal flooding
AR5 WGII SPM
15. African ecosystems are already being affected by climate
change, and future impacts are expected to be substantial
• Temperatures in Africa are projected to rise
faster than the global average increase during
the 21st Century,
• Under a high RCP, an exceedence of 2°C could
occur by mid-century across much of Africa and
reach between 3 and 6°C by the end of the
Century.
• Ocean ecosystems, in particular coral reefs, will
be affected by ocean acidification and warming,
thus negatively affecting economic sectors such
as fisheries.
• Climate change will amplify existing stress on
water availability in Africa.
• Increasing temperatures and changes in
precipitation are very likely to reduce cereal crop
productivity. This will have strong adverse effects
on food security.
AR5 WGII
17. Limiting Temperature Increase to 2˚C
Measures exist to achieve the substantial emission reductions required to limit
likely warming to 2°C (40-70% reduction in GHGs globally by 2050 and near
zero or below emissions levels in 2100)
A combination of adaptation and substantial, sustained reductions in
greenhouse gas emissions can limit climate change risks
Implementing reductions in greenhouse gas emissions poses substantial
technological, economic, social, and institutional challenges
Ambitious mitigation is affordable and translates into delayed but not foregone
growth (economic growth reduced by ~ 0.06% / BAU growth 1.6-3%). Estimated
costs do not account for the benefits of reduced climate change
AR5 WGI SPM, AR5 WGII SPM,AR5 WGIII SPM
But delaying mitigation will substantially increase the challenges associated
with limiting warming to 2°C
18. Adaptation Experience in Africa
Since 2007, Africa has gained experience in
planning and beginning to implement
adaptation activities, from local to national
levels and across a growing range of sectors.
However, across the continent, most of the
adaptation is reactive in response to short-
term motivations, is occurring at the
individual/household level, and lacks support
from government.
Africa’s urgent adaptation needs stem from
the continent’s foremost sensitivity and
vulnerability to climate change, together with
its low levels of adaptive capacity.
AR5 WGII
19. Inherent adaptation-related strengths in Africa include:
• The continent’s wealth in natural
resources
• Well-developed social networks
• Longstanding traditional
mechanisms of managing variability
through, for example, crop and
livelihood diversification, migration,
and small-scale enterprises,
• Local or indigenous knowledge
systems for sustainable resource
management
AR5 WGII
20. Adaptation needs in Africa
Since Africa is extensively exposed
to a range of multiple stressors that interact
with longer term climate change,
adaptation needs are broad,
encompassing:
• Institutional, social, physical, and
infrastructure needs
• Ecosystem services and environmental
needs
• Financial and capacity needs
• Making climate change information
more reliable and accessible is one of
the most pressing and cross-cutting
adaptation needs
AR5 WGII
21. Mitigation Measures
More efficient use of energy
Greater use of low-carbon and no-carbon energy
• Many of these technologies exist today
• Nearly a quadrupling of zero- and low-carbon energy supply
from renewable energy by 2050
Improved carbon sinks
• Reduced deforestation and improved forest management
and planting of new forests
• Bio-energy with carbon capture and storage
Lifestyle and behavioural changes
AR5 WGIII SPM
22. AR5 SYR SPM
“…stabilization of GHG concentrations in the atmosphere at a level that would prevent
dangerous anthropogenic interference with the climate system…” ~ Article 2 of the UNFCCC
Very likely more intense and
frequent extreme precipitation
events in many regions.
A likely nearly ice-free Arctic
Ocean in September before
mid-century (RCP8.5).
Very likely that global sea-level
rise will continue in the 21st
century (0.26-0.55m in RCP2.6
/ 0.45-0.82m in RCP8.5).
Projections of reductions of
renewable surface- and
groundwater resources in
some regions.
Projections of increasing
displacement of people, and
risks of violent conflicts.
The risk associated with
crossing certain thresholds
increases with rising
temperatures.
Effective decision making to limit climate change recognizes the importance of
ethical dimensions, equity, value judgments, economic assessments, and diverse
perceptions and responses to risk and uncertainty.
23. Climate change and equity
Issues of equity, justice, and fairness arise
with respect to mitigation and adaptation:
• Different past and future contributions to
the accumulation of GHGs in the
atmosphere
• Varying challenges and circumstances
• Different capacities to address mitigation
and adaptation.
Options for equitable burden-sharing can
reduce the potential for the costs of climate
action to constrain development.
AR5 WGIII
24. The window for action is rapidly closing
65% of our carbon budget compatible with a 2°C goal already used
Amount Used
1870-2011:
1900
GtCO2
Amount
Remaining:
1000
GtCO2
Total Carbon
Budget:
2900
GtCO2
AR5 WGI SPM