EVIDENCE OF CLIMATE CHANGE: Science, vulnerability and Impacts

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EVIDENCE OF
CLIMATE CHANGEScience, vulnerability and Impacts

• D. Okali
• Emeritus Professor of Forest Ecology
• University of Ibadan
• Chairman
• Nigerian Environmental Study/Action Team (NEST)
• d_okali_at_yahoo.com

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Outline

• Short story
• Evidence
• Science
• Impact, Vulnerability
• Consequences
• Actions

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Climate Change impact on livelihood?

• Achebe 1958 Things Fall Apart pp 21 - 22

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CC Impact on livelihood
The year that Okonkwo took eight hundred yams
from Nwakibie was the worst year in living
memory. Nothing happened at the proper time it
was either too early or too late. It seemed as
if the world had gone mad.
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CC Impact on livelihood

• The first rains were late and, when they came
  lasted only a brief moment. The blazing sun
  returned, more fierce than it had ever been
  known, and scorched all the green that had
  appeared with the rains. The earth burned like
  hot coals and roasted all the yams that had been
  sown.

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CC Impact on livelihood

• Like all good farmers, Okonkwo had begun to sow
  with the first rains. He had sown four hundred
  seeds when the rains dried up and the heat
  returned.

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CC Impact on livelihood

• He watched the sky all day for signs of rain
  clouds and lay awake all night

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CC Impact on livelihood

• In the morning he went back to his farm and saw
  the withering tendrils.

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CC Impact on livelihood

• He had tried to protect them from the smouldering
  earth by making rings of thick sisal leaves
  around them. But by the end of the day the sisal
  rings were burnt dry and grey.
• He changed them every day and prayed that the
  rain might fall in the night. But the drought
  continued for eight market weeks and the yams
  were killed.

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CC Impact on livelihood

• Some farmers had not planted their yams yet. They
  were the lazy easy going ones who always put off
  clearing their farms as long as they could. This
  year they were the wise ones

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CC Impact on livelihood

• They sympathized with their neighbours with much
  shaking of head, but inwardly they were happy for
  what they took to be their foresight

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CC Impact on livelihood

• Okonkwo planted what was left of his seed yams
  when the rains finally returned. He had one
  consolation. The yams he had sown before the
  drought were his own, the harvest of the previous
  year. He still had the eight hundred from
  Nwakibie and four hundred from his fathers
  friend. So he would make a fresh start.

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CC Impact on livelihood

• But the year had gone mad. Rain fell as it had
  never fallen before. For days and nights together
  it poured down in violent torrents, and washed
  away the yam heaps. Trees were uprooted and deep
  gorges appeared
• everywhere.
• Then the rain became less violent. But it
• went on from day to day without a pause.

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CC Impact on livelihood

• The spell of sunshine which always came in the
  middle of the wet season did not appear. The yams
  put on luxuriant green leaves, but every farmer
  knew that without sunshine the tubers would not
  grow.

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CC Impact on livelihood

• That year the harvest was sad, like funeral and
  many farmers wept as they dug up the miserable
  and rotting yams.

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CC Impact on livelihood

• One man tied his cloth to a tree branch and
  hanged himself.

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Climate change realNow the issue

• Early doubts rested
• At centre of international dialogue debate
• A security issue 2007 Nobel Peace Prize to IPCC
  and Al Gore
• Most serious threat to the poor
• No other single issue presents such a
• clear and present danger to the future
• welfare of the worlds poor (Christian Aid)
• Climate change strikes at the root of the
  foundation of the world economic system energy
  use

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Evidence

• IPCC Reports 1990, 1995, 2001, 2007
• Warming
• - 0.70C last 100 years
• - 1.8 - 6.40 C by 2100
• - 80 ocean to 3000 m depth
• - 1995 2006 warmest since 1850

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Evidence

• Melting ice
• Warming caused ice to melt global snow cover
  down by 10 since 1900
• - Arctic circle now sailable ecological
  consequences
• Sea Level Rise (SLR)
• Melting ice and thermal swelling lead to sea
  level rise
• Sea level up 10 25 cm past 100 yr now 3.1
  mm/yr

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Evidence

• Precipitation changes
• onset, cessation, intensity, amount
• Extreme weather events
• droughts, floods, cyclones, hurricanes, heatwaves
• Intensity, frequency

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CC in Nigeria (NIMET)
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Climate Change in Nigeria (NIMET)

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CC in Nigeria (NIMET)
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CC in Nigeria (NIMET)
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Causes of Climate Change

• Radiative forcing
• Alteration in balance between incoming and
  outgoing radiation in the Earths atmosphere
• Radiative forcing factors
• - changes in the concentration of
  greenhouse gases in the atmosphere
• - changes in aerosol conc
• - land cover changes
• - solar activity
• - volcanic eruptions

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Radiative Forcing Values
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Radiative forcing values(W m-2)

• Greenhouse gases
• CO2 - 1.66
• CH4 - 0.48
• N2O - 0.16
• Halocarbons - 0.34
• Aerosol/land cover - -0.7
• Solar - 0.12
• Aircraft - 0.01
• Total net anthropogenic - 1.6

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GREENHOUSE GASES

• CO2 (CARBON DIOXIDE)
• gt60 greenhouse effect
• 280 370 ppmv (31 increase since mid 19th
  Century)
• Sources
• Fossil fuels (coal, oil, gas) combustion for
  transport, manufacturing, heating , cooling,
  generating energy
• Biomass burning (firewood, bush burning, farm
  residues)
• Land use changes (deforestation, desertification,
  farming, settlements etc)

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GREENHOUSE GASES

• CH4 (METHANE)
• up to 20 greenhouse effect
• 700 1760 ppbv (151 increase since mid 19th C)
• Sources
• Decaying organic matter, garbage
• Wetlands, swamp rice
• Livestock production
• Fossil fuel production and combustion
• Biomass burning
• Waste water treatment

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GREENHOUSE GASES

• N20 (NITROUS OXIDE)
• ca 6 greenhouse effect
• 276 316 ppbv (175 increase since mid 19th
  Century)
• Sources
• naturally from soils and the ocean
• Soil cultivation nitrogen fertilisers
• Livestock production
• Chemical industry nylon manufacture
• Fossil fuel and biomass burning

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GREENHOUSE GASES

• HALOCARBONS (Cl, Fl, Br, I compds)
• up to 14 greenhouse effect
• Man-made prominent since 50s (also ozone
  depleting)
• Sources
• Industrial and home uses especially as
  propellants and refrigerants

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GREENHOUSE GASES
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GREENHOUSE GASES
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GREENHOUSE GASES
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OTHER RADIATIVE FORCING FACTORS

• Aerosols
• Soil dust, vehicular, Harmattan haze, sea salt,
  smoke, organic debris, pollen, spores,
  microorganisms, manufacturing dust, cement,
  construction, volcanic emissions
• Negative radiative forcing, cooling effect
• Land cover
• albedo
• Solar activity and volcanic eruptions
• solar irradiance varies up to 11 in 28 year
  cycle
• sulphate aerosols from volcanic eruptions

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Impacts, Vulnerability

• Changes listed above not even on all surfaces of
  Earth
• But all subject to climate change impact/effect
• - Impacts adverse, beneficial challenges and
  opportunities
• - Vulnerability extent to which adverse impacts
  do damage varies by geographical location,
  extent to which economic activities depend on
  climate level of economic development

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• Resilience degree to which system can withstand
  impact without changing to a new state i.e.
  ability to return to initial state after impact

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Consequences

• CO2 fertilization could have positive impact, but
  countered by higher respiration from warmer
  temperature
• Warm temperatures extend range of disease vectors
  e.g. malaria up warmer higher ground
• Increased intensity, severity and frequency of
  extreme weather-related disasters floods,
  droughts, wild fires
• Increased unpredictability of weather patterns
  disruption of agricultural activities, threat to
  food security

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Consequences

• Natural and human systems affected, exacerbated
  desertification, flooding, soil erosion, spread
  of water-borne diseases, biodiversity loss
• Ecological disruptions, economic losses,
  livelihood disruptions, heightened social
  conflicts
• Sea level rise coastal erosion, flooding,
  threat to economic activity, salt water intrusion
  into freshwater systems

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OUR COASTLINE
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OUR COASTLINE
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Action

• Global and local dimensions
• Framework for global governance
• UNFCCC (Stabilization of greenhouse gases within
  a time frame to allow ecosystems to adapt, food
  prodn and economic development to continue)
• Conferences of Parties (COPs) and various
  committees
• Mitigation and Adaptation

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Global action

• Kyoto Protocol firm commitments
• Clean Development Mechanism (CDM) challenges to
  opportunities
• Carbon trade certified emission trading,
  regulated and unregulated etc

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Local Action

• Local actions to combat climate change reinforce
  actions already being taken or planned for
  meeting development challenges
• Local action must be systematic, concerted and
  coordinated at the national level

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Framework for local action

• Administrative
• Focal Point,
• Designated National Authority (DNA) for CDM
• Reporting arrangements National communications

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Framework for local action

• Enabling institutional framework
• policies, strategies, An Adaptation
  Plan(Programme) of Action legislation,
  coordinating mechanisms
• Massive public awareness - to mobilize strong
  public and political support (Role of Media)
• Effective information management and networking,
  cooperation among stakeholders
• Improved knowledge base
• Integrating CC considerations into national
  planning and programmes

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Role of policy-makers

• Climate change involves complex interactions
  among climatic, environmental, economic,
  political, institutional, social and
  technological processes
• To be effective local action should be driven at
  the topmost level of policy making

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Role of Policy-makers

• Policy makers are best placed to decide which
  aspects of the problem are sufficiently important
  to invest time and resources on, which sectors or
  sections of the country to pay particular
  attention to, and the best ways by which
  government, donors and a range of stakeholders
  could work together, and with the international
  community, to address the problem.

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President YarAdua

• The consequences of Climate Change are
  frightening and life threatening. All countries
  are affected in varying degrees. The African
  continent is particularly vulnerable to the
  impacts of climate change, a vulnerability that
  is compounded by the continents massive
  infrastructure deficit, endemic poverty, and
  disease burden.
•  

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President YarAdua

• Nigeria with a population of over 140 million
  and growing at the rate of over 2 per annum, is
  extremely vulnerable to the adverse effects of
  climate change. The combined effects of
  desertification and soil erosion in the northern
  and southern parts of the country, respectively,
  continue to adversely impact on our agriculture,
  energy, biodiversity and water resources.

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President YarAdua

• Nigerias adaptation strategy is, therefore,
  necessarily mainstreamed into its developmental
  policies.

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• N

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