The document discusses the impacts of climate change on human and natural systems. It states that humanity is conducting an uncontrolled global experiment by polluting the atmosphere through fossil fuel use and population growth, with consequences that could be second only to a global nuclear war. These changes threaten global security and are already harming parts of the world.

3. Impacts
Humanity is conducting an unintended, uncontrolled,
globally pervasive experiment whose ultimate consequences
could be second only to a global nuclear war. The Earth’s
atmosphere is being changed at an unprecedented rate by
pollutants resulting from human activities, inefficient and
wasteful fossil fuel use and the effects of rapid population
growth in many regions. These changes represent a major
threat to international security and are already having
harmful consequences over many parts of the globe.
INTERNATIONAL CONFERENCE ON THE CHANGING ATMOSPHERE:
IMPLICATIONS FOR GLOBAL SECURITY
TOTONTO, JUNE 1988

4. Impacts
 Impacts refers to the consequences of climate change
on natural and human systems
 Roughly equivalent to risk
 Impact assessments take account of the probability of
a hazard (such as a certain rise in sea level) as well as
the sensitivity of the system to that hazard.
 Impacts can sometimes be beneficial

5. Impacts
 Deals with the key question: whether GHG emissions
will lead to unacceptable impacts on
Human Systems Natural impacts

6. Impacts
 Major Concern:
Is distinguishing it from the background noise of climate
variability.

7. Impacts Categorized into:
DIRECT IMPACTS INDIRECT IMPACTS
Socioeconomic activities:
Transport
Energy
Water Uses
Forestry
Tourism and Recreation
Health Services
Public Safety
Agriculture and Fisheries
Way of Life
Changes
in Yield

8. Climate Change Impacts- Reasons for Concern
 IPCC (2001 Report) – Summarized Impacts qualitatively
under 5 categories or reasons for concern

9. Reason 1: Risk to unique and threatened systems
 IPCC (2007 report) concluded that there is now good
evidence that recent warming is already strongly affecting
natural biological systems, both on land and in the seas.
Local
disappearanc
es
Polewards
shifts in
species Stress on
coral reefs Acidity of
oceans

10. Reason 2: Risks from extreme climate events:

11. Reason 2: Risks from extreme climate events:
 Observed increase in deaths and financial losses from extreme events
 Societies display counter-adaptive behavior through demographic shifts
into hazardous locations.
 Impacts become compounded by repeated events – systems may not
survive repeated extreme events

12. Reason 3: Distribution of Impacts
 Impacts will not be distributed equally over the globe
 Differs across sectors and regions
Most Vulnerable
Coastal Zones Low latitude Developing Countries

13. Reason 4: Aggregate Impacts
 The total of all market impacts may be small positive or negative
(1 or 2% of GDP) at small global warming
Reason 5: Risks from future large-scale discontinuities

14. Concept of vulnerability
 Vulnerability is defined as the residual risk:
Vulnerability = risk (adverse climate impacts) – adaptation

15. Pacific Regional Environment Programme (SPREP)
on Vulnerability
“Vulnerability [to climate variability] is the extent to
which a natural or human system is susceptible to
sustaining damage resulting from climate variability,
including extreme events, despite human actions to
moderate or offset such damage”.

16. IPCC on Vulnerability
“Vulnerability [to climate change] is the degree to which a
system is susceptible to, or unable to cope with, adverse
effects of climate change, including climate variability and
extremes.”

17. Characteristics of vulnerability
Vulnerability is a function of:
Sensitivity
Character
Magnitude
Rate
Climate variation
Adaptive Capacity

18. Uncertainty and Climate change
2 major categories of uncertainty
Science Human behaviour

19. Cascade of uncertainty
Schematic showing the cascade of uncertainty. Each bar represents the range of
uncertainty at that stage of modelling. Each step in impact assessments adds another
source of uncertainty, culminating in a huge uncertainty of the final possible
impacts. Adapted from Pittock (2009), Fig.12.
Emission
scenarios
Carbon cycle
response
Global climate
sensitivity Regional
climate change Range of possible
impacts

20. Coping range and the effect of climate change on
vulnerability
• Natural and human systems have been forced by past
natural climate variability to evolve or adapt
• Most of the time these systems operate within a
comfortable range of climate in which they operate
well
• Coping range’ – When systems exist in climatic
conditions in which they survive, but not well.

21. Coping range and the effect of climate
change on vulnerability
• Occasionally natural and human systems experience
extreme events that are damaging, sometimes fatally.
• These events are called natural disasters, and include
droughts, floods, storms urges, and wildfires.
• Climate change moves the average climate so that
comfortable conditions become less common and
extreme events, which can be defined as those falling
outside the previous coping range, become more
common for a greater severity.

22. Coping range and the effect of climate change on
vulnerability

23. Loss and Damage
 Loss and damage deals with impacts of climate change which
include slow onset events and extreme weather events which may
both result in loss and damage.
 Also deals with non-economic losses

25. Loss and Damage
 Example of extreme events include hurricanes, heat waves, etc.
 Slow onset events include increasing temperature, desertification,
loss of biodiversity, land and forest degradation, glacial retreat, sea
level rise, ocean acidification, and salinization. Activities under
this strategic workstream aim at improving the understanding of
slow onset events, as well as enhancing the capacity to address
them, particularly at regional and national levels.

26. Non-economic losses
 Non-economic losses are additional to the loss of property,
assets, infrastructure, agricultural production and/or revenue
that can result from the adverse effects of climate change.
 They cover loss and damage that are not easily quantifiable in
economic terms, such as loss of life, degraded health, losses
induced by human mobility, as well as loss or degradation of
territory, cultural heritage, Indigenous knowledge,
societal/cultural identity, biodiversity, and ecosystem services.

27. Warsaw International Mechanism
for Loss and Damage
 The Warsaw International Mechanism for Loss and Damage
(WIM) was established at COP19 in 2013.
 It is the main vehicle in the UNFCCC process to address loss
and damage associated with climate change impacts in
developing countries that are particularly vulnerable to the
adverse effects of climate change.
 Article 8 anchored loss and damage in the Paris
Agreement which was adopted at COP 21. Areas of
cooperation and facilitation to enhance understanding.

28. COP 27, 2023 - major advances in L&D
 An unexpected achievement on loss and damage
compensation funding - creation of a specific funding
arrangement
 Implementation of the Santiago Network which was
established at COP25 which aims to provide technical
assistance for vulnerable countries to deal with L&D

29. Disaster Risk Reduction
 Disaster risk reduction is the concept and practice of
reducing disaster risks through systematic efforts to analyse
and reduce the causal factors of disasters.
 Disaster risk reduction strategies and policies define goals
and objectives across different timescales and with concrete
targets, indicators and time frames.
 A global, agreed policy of disaster risk reduction is set out in
the United Nations endorsed Sendai Framework for Disaster
Risk Reduction 2015-2030, adopted in March 2015, whose
expected outcome over the next 15 years is: “The substantial
reduction of disaster risk and losses in lives, livelihoods and
health and in the economic, physical, social, cultural and
environmental assets of persons, businesses, communities
and countries”.

30. Disaster Risk Reduction
 Examples include:
 Developing building codes to ensure infrastructure can withstand
cyclones and other hazards
 Implementing measures to divert flood water
 Strengthening social protection systems to facilitate timely
assistance
 Planting drought-resilient crops
 Increasing water storage capacity in order to maintain water supply
in times of drought.
World Bank research (2021) identified a $4 benefit for each $1 invested
in more resilient infrastructure in low- and middle-income countries,
with this benefit doubling when climate change is taken into account.