EVIDENCE OF CLIMATE CHANGE: Science, vulnerability and Impacts D. Okali Emeritus Professor of Forest Ecology University of Ibadan & Chairman Nigerian Environmental

EVIDENCE OF CLIMATE CHANGE:Science, vulnerability and Impacts

D. Okali

Emeritus Professor of Forest Ecology

University of Ibadan

&

Chairman

Nigerian Environmental Study/Action Team (NEST)

[email protected]

Outline

Short story Evidence Science Impact, Vulnerability Consequences Actions

Climate Change impact on livelihood?

Achebe 1958 ‘Things Fall Apart’ pp 21 - 22

‘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.


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.


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.


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


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


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.


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


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


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 father’s friend. So he would make a fresh start.


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.


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.


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


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

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 aclear and present danger to the futurewelfare of the world’s poor’ (Christian Aid)

Climate change strikes at the root of the foundation of the world economic system – energy use

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

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

Evidence

Precipitation changes- onset, cessation, intensity, amount

Extreme weather events: - droughts, floods, cyclones, hurricanes,

heatwaves- Intensity, frequency

CC in Nigeria (NIMET)

Climate Change in Nigeria (NIMET)



Causes of Climate Change

Radiative forcing• Alteration in balance between incoming and

outgoing radiation in the Earth’s 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

Radiative Forcing Values

Radiative forcing values(W m-2)

•Greenhouse gasesCO2 - +1.66CH4 - + 0.48N2O - + 0.16Halocarbons - + 0.34

•Aerosol/land cover - -0.7•Solar - +0.12•Aircraft - +0.01•Total net anthropogenic - +1.6

GREENHOUSE GASES

CO2 (CARBON DIOXIDE)

– >60% 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)

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

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

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

GREENHOUSE GASES

Figure 2: Major CO2 Emission Sources

Gas Flaring30%

Transport20%

LULUCF40%

Other Energy6%

Industrial Processes

1%

Electricity Gen.3%

GREENHOUSE GASES

Figure 3: Major Sources of CH4 Emissions

Energy25%

Livestock19%

WWT32%

Rice Cult.18%

Other Agric.2%

LULUCF0%

MSW4%

GREENHOUSE GASES

Figure 4: Major Sources of N2O Emissions

Energy63%

Savannah Burning

28%

Biomass Burning:

Agric Wastes6%

Biomass Burning: Forest

Conversion1%

Biomass Burning:

MSW2%

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

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

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

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

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

OUR COASTLINE

OUR COASTLINE

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

Global action

Kyoto Protocol – firm commitments

Clean Development Mechanism (CDM) – challenges to opportunities

Carbon trade – certified emission trading, regulated and unregulated etc

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

Framework for local action

Administrative- Focal Point,- Designated National Authority (DNA) for CDM- Reporting arrangements – National

communications

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

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

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.

President Yar’Adua

‘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 continent’s massive infrastructure deficit, endemic poverty, and disease burden.


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.


Nigeria’s adaptation strategy is, therefore, necessarily mainstreamed into its developmental policies.

Documents

EVIDENCE OF CLIMATE CHANGE: Science, vulnerability and Impacts D. Okali Emeritus Professor of Forest Ecology University of Ibadan & Chairman Nigerian Environmental