Download Climate change in the Sahel

Permament Interstate Committee for Drought Control in the Sahel
AGRHYMET Regional Centre
Monthly Bulletin
Special Number
Climate change in the Sahel
A challenge for sustainable development
Word of welcome
Mohamed Yahya Ould Mohamed MAHMOUD
Director General of the AGRHYMET Regional Centre
Dear readers,
The Sahel sub-region was brought to the attention of the international community several decades ago by
the major droughts experienced in the early 70s and 80s. These climatic disturbances have greatly affected
the economies as well as ecosystems of this large geographic area in West Africa. The actions undertaken
by the Permanent Inter-state Committee for Drought Control in the Sahel (CILSS) and its partners, since
its establishment in 1973, have significantly contributed to mitigating the negative impacts of these weather
disturbances. However, the farming systems and ways of life of these essentially agro-pastoral populations of
the sub-region are still vulnerable to climatic hazards. Thus, the recent increase in localized yet at times very
devastating extreme events such as droughts and floods, is likely to undermine the countries’ efforts towards
achieving the Millennium Development Goals (MDG). Indeed, the sub-region experienced in 2007, 2008 and
2009 its worst floods for over 30 years. Losses caused by these floods are estimated at several billions of
dollars.
This situation which actually concerns not the Sahel region alone, is increasingly seen as a manifestation of
climate change caused by global warming, which is itself due to the increase in the content of greenhouse gases
in the atmosphere. Thus, climate change has become one of the major challenges for the entire planet to take
up, with its multiple facets, including impact assessments, and mitigation and adaptation measures.
Different institutions have been established at the international level to address the scientific, diplomatic and
legal aspects of these changes. Thus, the United Nations Framework Convention on Climate Change (UNFCCC)
has begun to sensitize the States, particularly those which have most contributed to the phenomenon through
their industrial and economic activities, and to obtain from them commitments towards reducing their emissions
of greenhouse gases. The activities undertaken through various international protocols, such as the protocol of
Kyoto, as well as the periodical meetings, including the COP15 which was held in Copenhagen (Denmark)
last December, are now designated by the term “global climate governance”. Action plans and frameworks of
cooperation on climate change have also been created at the national and sub-regional levels to better define the
problem and identify possible responses in terms of mitigation and adaptation.
CILSS, which has a critical mass of scientific information on the issue, has already initiated research, training
and advocacy actions on behalf of its member states. CILSS’ recognized expertise in this field led to her
being chosen to help for the implementation of national and regional programmes on science and adaptation to
climate change in West Africa.
This publication provides a framework for reflection and information-sharing through which the AGRHYMET
Regional Centre would contribute to the debate on climate change in West Africa. It is based on the work of
CILSS experts and focuses not only on the characterization of the phenomenon in our sub-region, its potential
impacts on vital sectors of the economy, but also on adaptation measures undertaken with the populations.
Enjoy your reading
CONTENTS
Global warming and increased
flooding
Climate governance
p5
p 12
The regional dimension of climate
change
p 14
Climate variability and change in the
Sahel
p 17
Impacts of climate change on food
security
p 21
Farmers’ perceptions of climate
variability
p 31
Local adaptation practices
p 33
Focus:
The Project : “ Capacity Building for adaptation to
Climate Change in Sahel ”
p 35
Some definitions
(Extracts from the United Nations Framework Convention on Climate Change)
1. “Adverse effects of climate change” means changes in the physical environment or biota resulting from
climate change which have significant deleterious effects on the composition, resilience or productivity of
natural and managed ecosystems, or on the operation of socio-economic systems or on human health and
welfare;
2. “Climate change” means a change of climate which is attributed directly or indirectly to human activity that
alters the composition of the global atmosphere and which is in addition to natural climate variability observed
over comparable time periods;
3. “Climate system”, means the totality of the atmosphere, hydrosphere, biosphere and geo-sphere, and their
interactions;
4. “Emissions”, means the release of greenhouse gases and/or their precursors into the atmosphere over a
specified area and period of time;
5.”Greenhouse gases” means those gaseous constituents of the atmosphere, both natural and anthropogenic,
that absorb and re-emit infrared radiation;
6. Vulnerability expresses the level to which a system can be degraded or damaged in response to changing
climate. It depends on both physical and socioeconomic factors.
7. Adaptation is the set of responses (solutions) to either positive or negative effects of climate change. It can
be achieved naturally or through spontaneous reaction (e.g., when faced with a climate catastrophe) or early
in the planning.
8. Climatic scenarios are long-term visions of future climate changes (i.e., climatic parameters) as well as
major socioeconomic parameters in a given locality. They help to assess the vulnerability of the region and
anticipate with adaptation measures.
4
Global warming
Global Warming is a phenomenon of increased average temperature of oceans and
the atmosphere at the global level and over several years. Today, this term is applied
to a global warming trend measured during the last decades of the 20th century. The
International Panel on Climate Change (IPCC, 2007), in its fourth report involving
2 500 scientists from 130 countries, says that it is very likely (probability > 90 %)
that the global warming observed since 1950 is of human origin.
by Dr. Benoît SARR,
AGRHYMET Regional
Centre
The earth has always experienced climate fluctuations characterized by alternations between cold periods
and warm periods. The earth has gone through several global warming and cooling cycles during the last
million years. These variations are due to changing trajectory of the motion of the earth around the sun, to
the orientation of its axis around itself, and to variations in the intensity of solar activity. Since the early 20th
century, the average temperature of the earth has experienced unprecedented increase.
This trend seems more correlated to the sharp increase in the atmosphere of concentration of greenhouse gases
(boxes 1 and 2) such as dioxide carbon (CO2), methane (CH4) and nitrogen dioxide (N2O). These gases are
considered as being mainly responsible for climate change.
5
Box 2: Sources and lifetime of the
main greenhouse gases
Box 1: Greenhouse effect
When solar radiation reaches the Earth’s
atmosphere, some (28%) is directly reflected
(returned to space) through the air, clouds
and the Earth’s surface (especially bright
surfaces), this is the albedo. Incident rays
which were not reflected back into space are
absorbed by the atmosphere (21 %) and land
surface (51 %). This part of the radiation
which is absorbed by the Earth generates
heat (energy) which is returned in turn,
particularly at night and in winter, towards
the atmosphere as infrared rays: this is the
blackbody radiation, which is partly absorbed
by greenhouse gases, then re-emitted as heat
towards the Earth, which is called greenhouse
effect. Without this phenomenon, the Earth’s
average temperature would be about -18° C,
whereas observations show an Earth’s average
temperature of about + 15 °C. Depending on
the emission scenarios of greenhouse gases,
which are closely related to the demographic,
technologic and socioeconomic evolution of
the world, global temperatures could reach +
16.5° C to 19.5 ° C (Figure 1). Constituents
of the atmosphere further contributing to the
phenomenon of greenhouse effect include
water vapour, carbon dioxide, ozone, methane
and nitrous oxide
Carbon dioxide is the most abundant
greenhouse gas emissions. It comes mainly
from the use of fossil fuels (oil, natural gas,
charcoal), certain industrial activities (cement
and chemical industries), deforestation and
certain agricultural practices) (Figures 2 and
3). Its growth rate is 0.4 % per year on average
and its lifetime in the atmosphere is 150 and
200 years. Nitrous oxide comes from fertilizer
application on soil in the farming sector in
particular. Its growth rate is 0. 25 % per year
on average and its lifetime in the atmosphere
is 120 years. Methane comes mainly from
decomposition or fermentation processes;
digestion of ruminants; emanations from
coal mines; landfills; wastewater treatment.
Its radiative power is 21 times higher than
that of carbon dioxide. Its growth rate is
on average 0. 6 % per year and its lifetime
in the atmosphere is 12 years. Greenhouse
gases are industrial gases used as refrigerants,
electric insulators or conductors of heat.
These are chlorofluorocarbons (CFC), hydro
fluorocarbons (HFC), perfluorocarbons (PFC),
and sulphur hexafluoride (SF6). They have a
lifespan longer than natural greenhouse gases,
and efforts are underway to ban some, and/or
reduce their production and use
Figure 1 Greenhouse effect and average
temperature across the globe
Figure 2: Shares of different anthropogenic greenhouse
gases in total emissions of 2004 (in CO2 equivalent),
source IPCC, 2007
6
Thus, the international climate negotiations held in
Copenhagen in December 2009 during the COP15
included, to that end, the numerical target of
limiting the rise in average global temperature to 2
°C. However, this conference failed to produce an
agreement on reducing, quantitatively, greenhouse
gas emissions by the biggest polluting countries
(Table 1).
Concerning Africa, which is regarded as the region
contributing the least to the emissions of greenhouse
gases and the most vulnerable to the effects of climate
change, it will have to find its way into the game of
international policies on mitigation and adaptation.
This requires strengthening the capacity of African
professionals in the field of climate governance.
Figure 3: Contribution of the various sectors to total
emissions of anthropogenic greenhouse gases in 2004
(in CO2 equivalent ), Source IPCC, 2007
Given the current level of emissions of greenhouse
gases and their lifetime in the atmosphere, it is very
likely that global warming would continue even in the
coming decades
Table 1: 10 leading contributors to greenhouse
gas emissions in the world
Country (or
region)
United States
European Union
China
Russian Federation
Japan
India
Canada
South Korea
Mexico
Australia
CO2 emissions (average
2000-04)
Total
Per capita
5 700
19
3 870
8
3 670
3
1 520
11
1 200
1 020
540
445
360
350
9
1
16
9
3
16
Current and future trends of air temperatures
globally and in Africa
The global warming is a reality in the light of current
developments of temperatures observed since the 19th
century. The observed temperatures show a general
upward trend across the globe. The average surface
temperature has risen by 0.6 ºC+ or - 0.2 ºC since
1860. The observations indicate that the 20th century
probably experienced the greatest warming of all ages
since 1 000 years in the Northern hemisphere. The
decades 1990 and 2000 were the warmest of the 20th
century (Figure 4). The years 1998, 2005, 2003 and
2002 were the warmest on record since 1861. Since
1976, the rise in temperature has been sharp, reaching
0.18°C per decade. The linear trend of warming over
the last 50 years, from 1956 to 2005 (0.13° C per
decade) is almost twice that of 100 years, from 1906
to 2005.
Source : International Energy Agency (2007)
The IPCC recommended reducing greenhouse gas
emissions across the entire planet by 25 to 40% by
year 2020, relative to 1990 reference year chosen in
the Kyoto Protocol.
Figure 4: Temporal evolution of temperature anomalies
on the Earth surface in Africa
7
Temperatures in West Africa and particularly in the Sahel have changed somewhat faster than the global trend,
with increases ranging from 0.2°C to 0.8°C per decade since the late 1970s in the Sahel-Saharan, Sahelian and
Sudanian zones (ECOWAS-SWAC/OECD/CILSS, 2008). The observed increase is however more important
on minimum temperatures (up to +1°C) than maximum ones (up to + 0.5°C). According to observations on the
climate, it appears that Africa has suffered a rise in temperatures of 0.6 to 0.7 °C, faster than the global average.
The example of the station of Tillabery, in the Sahelian zone of Niger, constitutes a perfect illustration of this.
Since 1980, higher temperatures have increased markedly and have become continuous. The current period
1990 -2007 has been particularly hot (Figure 5). Temperature differences between the current period and the
period 1951-1979 have reached + 0,99 °C for average temperatures. The rise in minimum temperatures is +1.
44 °C against +0.53 °C for maximum temperatures (not showed).
Figure 5: Inter-annual evolution of annual average temperature anomalies at Tillabery (Niger) from
1951-2008 compared to the normal period 1961-1990
In addition, this region could experience a warming of about 3 to 6 °C by 2100 according to the emission
scenarios, despite its marginal contribution to GHG emissions.
The IPCC (2007) confirms these perspectives on the continent. In the 21st century, global warming will be
greatest in Africa than in the rest of the world. The rise in average temperatures between 1980/99 and 2080/99
will range between 3 and 4°C over the entire continent, i.e., 1.5 times higher than global. This rise would be
within +3°C in the coastal areas (Senegal, Guinea Bissau). It will be higher (+ 4°C) in Continental Sahel (Mali,
Burkina Faso, Niger).
Global warming combined with increased variability
of rainfall and the increase in extreme events
(droughts, flooding) has significant impacts on
natural and human systems. Without appropriate
coping measures, the agro-silvo-pastoral and fishery
systems will be severely weakened.
Figure 6: Temperature and rainfall trends in
Africa between 1980/1999 and 2080/2099
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Return of heavy downpours and floods in a context
of changing climate
by Dr. Benoît SARR, AGRHYMET Regional Centre
After the droughts of the 70s and 80s, the West African countries, especially those in the Sahel, are suffering
today the effects of heavy rains and devastating floods. Damage and losses related to these extreme hydro
climatic events have been evaluated at several hundreds of billions of Francs. In addition, these events have
undermined human systems (human and material losses), farming systems (crops submerged) and economic
infrastructure (roads, bridges, dams destroyed), which impedes the availability, accessibility, and supply of
food and results in higher market prices. They were also the source of very important psychological impacts,
particularly on the most vulnerable groups of people. These events could intensify and become more frequent
in this context of changing climate.
More than 80 to 90 % of natural disasters are due to hydro climatic events such as droughts, heavy downpours,
and floods (WMO 2006). And yet, according to the IPCC (2007), it is established very likely (probability >90)
that heavy precipitation events, devastating floods and heat waves will continue to become more frequent
worldwide.
These events will become more intense and particularly more variable from one year to another. The extreme
rainfall associated partly with the increase in atmospheric water vapour, will increase with the climate change,
thus enhancing the condensation-rainfall-runoff cycle. We can therefore expect, over the coming years,
contrasting situations in which drought alternates with excess rainfall. The result would be an increase in
hydro climatic disasters (IUCN, 2004). Thus, the observations have shown significant change to the system of
extreme weather events over the last 50 years, in terms of frequency and intensity.
So, significant increases in heavy rainfall events accompanied by storms were observed worldwide. The
surface area affected by drought has increased since the 70s. Studies carried out by CRED/ UNISDR (2006)
have shown growing and rapid change in the number of natural disasters all over the world. This number
increased from 50 in 1975, to 200 in 2000 to over 350 in 2005.
A titre d’exemple, l’OMM avait ainsi considéré l’année 2007 comme celle des extrêmes en raison des climats
For example, the WMO had thus considered 2007 as a year of extreme events because of the extreme climates
recorded all over the world. Indeed, in 2007 many parts of the world experienced extreme weather events,
with heat waves, and many cases of cyclones and storms. Moreover, the number of extremely wet seasons is
expected to increase from once every twenty years in the late 20th century to once every five years in the next
century (Christensen, et al. 2007). Thus, according to FAO (2007) “the possibility that the recent floods in the
Sahel and in West Africa in general may be the consequence of climate change” must be taken seriously.
West Africa has not been spared by these events. An exponential increase in the number of floods resulting
from heavy rains has been observed. The number of events increased on average from less than 2 per year
before 1990 to more than 8 or 12 on average per year during the 2000s.
9
According to WFP (2007), ”the floods in Africa in 2007 that stretched from Mauritania in the West to Kenya
in the East” are considered the worst in decades. More than one million and a half people have been affected,
including more than 600,000 in West Africa.
Thus, in some CILSS and ECOWAS countries, namely Burkina Faso, Senegal, Mali, Niger, Mauritania,
Togo, Benin, etc., floods have caused important damage to economic infrastructure (bridges, roads, railways)
and other essential goods to provide health services and ensure delivery of relief.
Examples of recent extreme hydro climatic events in the CILSS/ECOWAS zone and their
consequences
2005: Between 16 and 22 August, Dakar recorded 367 mm of rain, more than half the average
annual cumulative rainfall. This has led to flooding of many homes in the suburbs and that of the
National Highway 1.
2007: Worst floods in West Africa for over 30 years with 33 deaths in Burkina Faso, 23 in North
Togo, 46 000 displaced including 26 000 in Burkina Faso and 14 000 in Togo. In Burkina Faso,
17 689 ha of crops flooded, loss of production of about 13 500 tonnes, 55 dams whose dykes gave
way.
2008: The heavy rains in the region of the Hauts Plateaux in Central Togo have destroyed thousands
of arable land, and over 30 000 houses and 6 dams, over 10 000 displaced, 20 deaths, 68 bridges
collapsed, including that of the National Highway 1 at Amakpapé.
Benin: destruction of 25 000 ha of food crops and 1204 ha cotton field, about 53 674 farmers
affected. Damage estimated at F CFA 9. 4 billion.
2009: Heavy downpours and floods in Burkina Faso: Ouagadougou and its environs which registered
in 2009, between September 1st and 2nd, a cumulative rainfall of 263 mm. These rains are 130 %
higher than the 90th percentile (extreme rain) causing over 150 000 homeless and 8 deaths, and the
destruction of several bridges; over 9300 ha of crops were flooded countrywide.
Adapted by Sarr B. 2009
In general, the costs of these floods – estimated at several billion dollars – clearly exceed, in some cases, the
costs of adaptation. For example, between 2000 and2008, the amounts of damage due to flooding in the CILSS
zone were estimated between US$ 39 and 80 billion respectively for the lower and higher case scenarios
(Table 1).
Table 1: Estimated costs of damage in US$ (*1000) per country in the CILSS zone (2000-2008)
CILSS country
Minimal scenario
Maximal scenario
7 363 935
15 114 902
78 750
161 639
Mali
5 860 665
12 029 353
Niger
8 545 725
17 540 594
Senegal
11 955 105
24 538 543
Mauritanie
5 568 255
11 429 165
42 750
87 747
39 415 185
80 901 943
Burkina Faso
Guinée Bissau
Gambie
Total
Source : DPC, Senegal, 2009 (data from Cap Vert and chad not avalaible)
10
In addition, the socioeconomic, health and psychological impacts on more vulnerable groups are significant.
Finally, these events contribute to the disruptions of markets (availability and accessibility, price increase) and
consequently to increase food insecurity, conflict and climatic migrations.
In the absence of adaptation and/or vulnerability mitigation measures in the agricultural sector, much of the
population would be exposed to situations of food insecurity due to these extreme events.
To mitigate vulnerability of natural and human systems vis-à-vis these extreme events, it is necessary to:
-
-
develop systems for forecasting, prevention and management of natural disasters by supporting regional
climate and water centres for the development of forecasting models, methods based on high resolution
remote sensing to monitor extreme events and undertake analyses on the probability of occurrence of
these events,
improve regional and national information systems for the timely warnings of the population in case
of disaster risk;
consolidate initiatives for disaster risks mitigation through preparedness and sensitization of the
populations,
conduct studies on new techniques of civil engineering and on quality construction materials for an
adaptation of infrastructure to extreme events.
These actions are to be carried out by national and regional centres on climate and water resource monitoring,
meteorological services, universities, regional and national platforms on natural disaster risk mitigation, civil
protection departments, civil society, NGOs, the populations, and the United Nations Systems (WFP, OCHA,
UN ISDR, FAO, UNDP, WMO), etc.
Floods in Ouagadougou (september 2009)
11
Climate governance
Today, the issue of climate change is a source of concern to everyone, including
scientists and policymakers who, in recent years, have been organizing endless
high-level meetings in their efforts to provide answers to this problem which
affects the lives of the people.
by Papa Oumar DIEYE,
AGRHYMET Regional Centre
Internationally, the United Nations Framework
Convention on Climate Change (UNFCCC) was
adopted in New York on May 9, 1992. The convention
is a non-binding treaty which commits the Parties
to cooperate together to stabilize greenhouse gas
emissions to a level that does not threaten the global
climate. It was later supplemented by the Kyoto
Protocol in 1997 to establish concrete and binding
reduction of emissions of six (6) key greenhouse
gases.
Finding gaps in the scientific evidence of climate
change, the World Meteorological Organisation
(WMO) and the United Nations Environmental
Programme (UNEP) set up in 1988, the InterGovernmental Panel on Climate Change (IPCC) to
collect and evaluate scientific data on the subject.
The IPCC acts as supreme body for the governance
of global science on the climate. In addition to the
political, institutional and scientific Governance of
the climate, the international community also set
up several funding mechanisms such as the Global
Environment Facility, the Adaptation Fund and the
Carbon Fund.
12
The Climate Summit held from 7 to 18 December
2009 in Copenhagen (Denmark) had been announced
by many climate change experts as a turning point
because it will lead to binding decisions to urge
countries to make efforts towards reducing greenhouse
gas emissions. But, for many institutions, such as
the Agence de l’Environnement et de la Maîtrise de
l’Energie (Environmental and Water Management
Agency) (ADEME, 2010), the commitments made
in terms of reducing GHG emissions in Copenhagen
are not sufficient. Those of China and the United
States (the 2 biggest emitters of GHG) were eagerly
expected. But they refused to be imposed emission
quotas, thereby avoiding any binding target.
The United States, which emits almost a quarter of
global GHG, had not ratified the Kyoto Protocol.
In Copenhagen, they pledged to reduce their CO2
emissions by 17 % by 2020 compared to 2005.
This is the first reduction of the country’s history.
This commitment must still be validated by the US
Congress to be implemented.
China, one of the largest emitters of greenhouse gases
in the world, proposed to reduce from 40 to 45% its
carbon intensity (amount of CO2 emitted per unit of Gross Domestic Product (GDP) by 2020 compared to
2005. But, given its growth, this effort could mean a doubling of Chinese emissions in 2020 compared to
2005. In addition, China made this commitment subject to the rich countries helping developing countries to
implement verification measures under the agreement.
The European Union, meanwhile, has the ambition to set a 30% reduction target of GHG emissions by 2020
compared to 1990 (against 20% fixed in the Kyoto Protocol).
At the national and West African sub-regional level, all the countries have signed and ratified these legal
instruments for the international governance of climate. This support for the cause of climate resulted in
the establishment, in each country, of inter-ministerial and integrating institutional frameworks (national
committees on climate change, national sustainable development councils, etc.) for a better understanding and
conduct of activities on climate change.
Just like the other large geo-strategic and business interest groupings in the world, the West Africa sub-region
has established political, economic and monetary integration bodies such as ECOWAS and UEMOA/WAEMU,
river basin organisations like ABN, VVA, OMVS, and specialized technical institutions like CILSS, etc. The
impacts of climate change being trans-national, these organisations have started working together for many
years towards taking into consideration the regional and sub-regional dimension of climate change. This led
to the formation of the Group of African negotiators, the establishment, by the African Union, of the meeting
of Ministers of Environment, the organisation of consultations at the sub-regional level etc., for the definition
of an appropriate sub-regional institutional framework.
13
The regional dimension
of climate change
It should be remembered that only countries are Parties to the United Nations
Framework Convention on Climate Change. By signing and ratifying these legal
texts on international climate governance, these countries have committed to
working together to stabilize, mitigate or terminate the process of disturbance of
the climatic system. . This awareness, which has started since the Rio Conference
in 1992 is trying to mobilize and achieve consensus over the need to fight together
against the global warming..
by Dr. Hubert N’DJAFA
OUAGA, AGRHYMET
Regional Centre
The creation of the Intergovernmental Panel on Climate Change (IPCC) by the World Meteorological
Organisation (WMO) and the United Nations Environmental Programme (UNEP) aims at producing reliable
scientific information on global climate. The various reports published by this international scientific body on
climate have then shown that, beyond the countries, there is an urgent need to also understand and act at the
regional and sub-regional levels, like in sub-Saharan Africa or in the Sahel, also considered as the region most
vulnerable to climate change phenomena.
Under the efforts of the Parties to the Convention, we note the production (more or less regular) of information
on climate change through the development of National Communications. These data are valuable benchmarks
on the level of contribution of each country to greenhouse gas emissions. These countries also committed
themselves to undertake concrete actions (adaptation/mitigation) against the negative effects of climate change
14
through funding mechanisms provided for that purpose. The National Action Programmes for Adaptation
(NAPA) is a perfect illustration thereof. Today, virtually all ECOWAS and CILSS countries have their NAPA,
but none has had a rocky start running, whereas they are plans for priority and immediate adaptation actions.
Climate change knows no borders; so, the IPCC is increasingly recommending taking also its regional or subregional dimension into consideration. Therefore, this dimension of climate change began to be taken into
account. The numerous appeals to the intergovernmental organisations in the sub-region are set to reflect this
new reality for managing climatic risk.
In the West Africa sub-region, the Permanent Inter-State Committee for Drought Control in the Sahel (CILSS)
- created in 1973 and composed of nine (9) countries - is a form of regional adaptation to cope with consequences
of the major drought of the early 70s. So, climate is behind the creation of CILSS. It is therefore natural that the
organisation took an early interest in the issue of climate change by participating, in a united front, in the Rio
Conference in 1992 and obtaining from the COP8 in New Dehli (India) in 2002, an observer status, Fortified
by this status, CILSS is firmly committed to taking the regional dimension of climate change into account. So,
the CILSS sought and obtained funding from the Canadian Government through the Canadian International
Development Agency (CIDA) for the regional Project entitled: “Capacity Building for Adaptation to Climate
Change in the Sahel”.
Today, this experience has been spreading, as evidenced by the numerous sub-regional initiatives underway
on climate change in West Africa. These initiatives include the development process of the sub-regional action
plan to reduce vulnerability to climate change in West Africa and Chad on climate change (SRAP-RV-WA).
West Africa and Chad develop a sub-regional action plan to reduce vulnerability to climate change
(SRAP-RV-WA)
Developing the SRAP-RV-WA is an expression of the will of participants in the International Conference on
the reduction of vulnerability of natural, economic and social systems to climate change in West Africa, held
from 24 to 27 January 2007 in Ouagadougou (Burkina Faso), through its pertinent recommendation n°4. The
recommendation states that: ”CILSS, in collaboration with ACMAD, ECOWAS and UNECA, will establish
a working group that will be responsible for developing a sub-regional action plan to reduce vulnerability of
natural, economic and social systems to climate change in West Africa and Chad. ECOWAS and CILSS will
take measures deemed necessary for the adoption of the plan by the Heads of State”.
At the end of this conference, the institutions involved signed a memorandum of understanding defining the
terms and spheres of responsibility for the implementation of this recommendation. United within this legal
framework, they led the process up to the recruitment of a Consulting firm for the development of the SRAPRV-WA, the draft of which is divided into two main parts:
Part 1: Overview of West Africa’s vulnerability to climate change and intervention strategies;
Part 2: Strategic action plan.
Part 1 of the SRAP-RV-WA highlights the degree of vulnerability, ongoing efforts, factors and gaps limiting
the fight against climate change in the sub-region.
The second part of the action plan provides the broad strategic policies on which to base actions against
climate change at different geographical scales.
The programme’s vision is outlined as follows: “the population, economies and governments in the region are
adapting continually and effectively to climate change”. The overall objective is as follows: ”At the regional
level, to develop mechanisms, stakeholders and capacities needed to support governments and communities
to adapt to climate change”, from which are derived the three specific operational objectives below:
•
•
•
Regional institutions provide political, technical and financial support to the States and economies in
their process of adaptation to climate change;
National stakeholders are adopting harmonized and coordinated approaches to adapt to climate
change;
Climate change is integrated into regional and international priority investments, programmes and
projects.
15
This ambitious programme is therefore a reference framework of actions for a concerted struggle of the subregion against the adverse effects of climate change. It is meant to be an integrative framework which is open
to any funding initiative (bilateral or multilateral) in the sub-region. The operationalization of the SRAP-RVWA will be based on the principle of subsidiarity according to predefined scales with appropriate institutional
framework. The SRAP-RV-WA will be submitted for adoption at a meeting of ECOWAS Ministers, preceded
by that of Experts. Adoption of the SRAP-RV-WA by the ECOWAS authorities is a strong signal of the subregion addressed to the international community as a true indicator of its commitment. After its implementation,
the sub-region could claim to contribute significantly to global efforts to safeguard the climate system alongside
the international community.
16
Climate variability and
change in the Sahel
understanding the current situation by observing
By Dr. Abdou Ali, AGRHYMET
Regional Centre
The climate of a period, as used in this analysis, refers to averages and irregular
variables such as temperature, rainfall and wind. The relative importance of
each of these variables depends on the region of the world considered. In the
Sahel, rainfall is by far the most decisive climate variable affecting the lives
of people; some authors consider that this variable alone can determine the
evolution of the environment in this region of the world. Rainfall can therefore
be regarded as the most appropriate indicator to characterize or analyze climate
change in the Sahel
Changing rainfall in the Sahel is characterized by
two distinct periods, namely: the period 1950 – 1969,
which was marked by a succession of wet years and
the period 1970 – 1993 by the persistence of dry years.
The end or not of drought in the Sahel is currently a
debate within the scientific community. Some analyses
conclude at the end of the phenomenon while others
stress its continuity. Another aspect of the question
is whether the situation being experienced by the
Sahel rainfall is a manifestation of climate change or
a natural variability of the phenomenon. What can
we attribute this situation to? This analysis aims at
contributing to the debate by making, on the basis of
rainfall data for CILSS member countries centralized
at the AGRHYMET Regional Centre, a diagnosis on
17
the current trend of rainfall in the Sahel.
Consensus on the situation before the year 1993
To determine the wet or dry character of the rainy
season, we often use the standardized precipitation
index (SPI). For a given year, this index is the
average cumulative seasonal rainfall of available
rainfall stations. Thus, the SPI indicates whether
the season can be described as surplus (positive) or
deficit (negative) season.
An analysis of the Sahelian SPI, calculated on the
basis of data from 600 stations monitored by the
AGRHYMET Regional Centre, shows two distinct
periods (Fig. 7 blue and pink parts). The first period,
from 1950 to 1969, is characterized by a persistence
of wet years and the second period, from 1970 to
1993, by a persistence of over twenty dry years.
The 70s mark what is commonly called the climate
fracture in the Sahel. No such rainfall behaviour was
observed in any other part of the world. This analysis
is a consensus within the scientific community. Many
international programmes have studied rainfall in the
region to try to explain this phenomenon, the latest
and most ambitious being the AMMA Programme
(African Monsoon Multi-disciplinary Analysis). The
drought observed in the Sahel during the period 19701993 also had no equivalent in the spatial dimension:
it has hit the entire region, without exception
The current situation, a subject of controversy
Based on the analysis of Fig.7 (green part), the least
we can say is that a change occurred after 1993.
Three very wet years were recorded in the Sahel:
1994, 1999, and 2003. What should we infer from
this? Is this the end of the drought that has battered the region so much? That is what the scientific
debate is all about. By observing Fig. 6, we suggest
to speak rather of the emergence of another mode
of inter-annual variability in rainfall, characterized
by sudden alternation between very wet years and
very dry years, than talking about dry or wet period,
in reference to the situation before 1993. The interannual variability in rainfall has increased with the
new mode of variability, which makes it even more
difficult to predict inter-annual rainfall in the Sahel.
To better understand the current situation, we carried
out a zonal analysis of the region, distinguishing the
Eastern part (corresponding to the Chadian part and
Eastern Niger) from the Western Sahel (corresponding
to the main area of Senegal and the Western part of
Mali) and the central part (east-central Mali and eastcentral Niger). The results show that the alternation
between wet and dry years, observed across the Sahel
as a whole, conceals a climatological fracture between
the West and the East. Drought continues in the
Western part, while the East is experiencing a return
of wetter conditions (Fig. 8). In this context, it is not
wise to continue to consider a global index and derive
an overall characteristic of rainfall for the Sahel: it is
necessary to distinguish between the Eastern part and
Fig. 7: Sahel Rainfall Index (SRI) over the period from 1950 the Western part. Thus, while the trend of drought of
to 2006. The positive values show higher rainfall years than
the years 1980 and 1990 continues in the western part
the average of the period 1950–2006 and the negative values of the Sahel, it is ending in the eastern part. Several
indicate years of lower rainfall than this average.
current climate studies are beginning to pinpoint
the reasons behind these new developments. Some
explain it by the westward shift of the warm focus of
the Indian Ocean, which resulted in the drought area
moving westward (Hagos and Cook, 2008)
18
Fig. 8: Rainfall index for Western and Eastern Sahel. The values of annual indices are averages calculated on a fiveyear period basis to highlight the major trends.
The return of precipitation in the Eastern part is also observed on the isohyets map (Fig. 9). For the Eastern
Sahel, there is northwards shift of the isohyets for the period 1994 – 2006 compared to those of period 1970
– 1993, when they are merged for the Western part.
Fig. 9: Comparison of isohyets over different periods: 1950 – 1969 in grey strips, 1970 – 1993 in red curves and 1994
– 2006 in blue curves.
Have rainy seasons become shorter?
Another recurring concern is the duration of the rainy season. Does the season start later and/or end early? To
answer this question, it is necessary to compare the beginning and end of the rainy season in the current period
compared to previous years. There are several definitions of the beginning or the end of the rainy season
(agronomic, hydrological, and meteorological definitions). The approach considered here was to compare
the average rainfall at the beginning or end of the rainy season in different periods. To do so, the average
daily cumulative rainfall of wet years in the period before 1993 is compared to those of dry years. The same
comparison was made for the post 1993 period. We find that for the period before 1993 (Fig. 10, left), the dry
years are actually characterized by a decrease in average daily rainfall for both the beginning and the end of the
season. On the other hand, for the period after 1993 (Fig. 10, right), the average seasonal cycles of wet years
and dry years differ only on the end of the season. The dry seasons of the current period are thus characterized,
on average, by a reduction of rainfall at the end of the season, but not necessarily at the beginning. The two
curves overlap until about 15 June.
19
Fig.10: Average seasonal cycles of wet years and dry years for the period before 1993 and after
Conclusion
This study, which is based on rainfall data collected by CILSS member countries, helped to restore some basic
characteristics of the current trend in rainfall in the Sahel.
From 1970 onwards, a persistent drought occurred in the Sahel. However, after 1993, another mode of variability
seems to develop within the Sahelian rainfall. The inter-annual evolution, viewed across the entire region, has
shown a strong alternation between very wet years and very dry years. This new mode of variability makes it
even more difficult to make inter-annual predictions and necessitates new adaptation strategies.
It is clear from the analysis it does not seem appropriate to express the current rainfall regime in the Sahel in
terms of end of drought or not, as there is no single trend. Two different rainfall trends are identified for the
current period. The tendency to drought continues in the Western Sahel, while the East is experiencing gradual
return to wetter conditions. The climate divide between the East and West also expresses an increase in spatial
variability of rainfall. It renders ineffective the vision of a generally wet or dry Sahel. That result from data
analysis should help to guide scientific research to better understand the basic physical reasons.
Are these changes a manifestation of sustained change in climate due to human action or is it just a natural
climate variability? It is difficult to determine absolutely. We need to understand the causes in order to respond.
According to the World Meteorological Organisation, the climate must be assessed relative to a reference
period of 30 years. In that context, several statistical studies have shown that the changes recorded after the
70s are more significant compared to the 1940 – 1969 reference period. Similarly, statistical tests for detecting
changes in trend have shown that the years 1970 and 1993 are years of climate failure.
According to the IPCC (International Panel on Climate Change), greenhouse gas emissions are the main
driver of climate change. Then, can we attribute the changes observed across the Sahel to these emissions?
A scientific consensus is currently emerging to attribute these changes to the complex interaction of several
factors with different scales. The role of change in ocean conditions affecting the monsoon, the role of retroaction between the atmosphere and land surface conditions or a change in the main currents of atmospheric
circulation (especially West African jets) were studied. Charney (1975) was a precursor, citing the important
role of change in vegetation and land use. Giannini et al. (2003) have shown that 25 to 35% of change in
rainfall can be explained by the role of oceans. Indeed, the persistence of drought in the Sahel is explained by
the combined effects of a warming of the inter-tropical part of oceans, particularly the equatorial zone of the
Indian Ocean, and enhanced temperature gradient of the Atlantic Ocean surface. This gradient is characterized
by relative warming of South Atlantic and a cooling of North Atlantic. However, several studies (Rotstayn
et al. 2002), for example) have concluded that this configuration of the surface temperature of the oceans is
linked to industrialization and emissions of greenhouse gases.
20
Impacts of climate change
on food security
The impacts of climate variability and change on Sahelian ecosystems are clear. The sectors most affected
are Agriculture, through land degradation, decrease in productivity of crops, livestock and water resources.
Impacts on these sectors have negative effects on the populations given the fact that rural populations account
for more than 80% of the entire population.
21
Impacts on agriculture
by Dr. Benoît SARR, AGRHYMET
Regional Centre
and
Dr. Seydou TRAORE, AGRHYMET Regional Centre
Following the recommendations of the Intergovernmental Panel on Climate Change (IPCC, 2007)
on future evolution of the global climate, the recent
climate negotiations in Copenhagen, in December
2009, were focused on limiting the global warming to
2 °C. Increased temperatures and rainfall variability
represent a serious threat to agricultural development
in the world, including West African countries and
may undermine efforts by the countries to achieve
food security. Higher temperatures associated
with greater variability in precipitation will cause
malfunctions of agricultural seasons, disruption of the
biological cycles of crops and damage to agricultural
production. The simulations in the tropics using agro
meteorological models enable to analyze the response
of crops to rising temperatures.
A study on the variation of maize yields in temperate
and tropical zones based on several assumptions of
global warming showed that in temperate zone, the
temperature increase to 2°C could be beneficial for
the maize yield (Figure 11). In contrast, in tropical
zones, yields fall immediately when the temperature
rises by 1 °C (André et al. 2003). At + 2°C, we note
a fall in maize grain yields by over 5 % in tropical
zones; which shows that even in a context of moderate
warming of the climate, the temperate zone would be
winning and the tropical zone losing.
Crop response to temperature
Plants are equipped with an “internal clock” that
governs their development phases. Each species
or variety is characterized by its temperature
requirements during its various development stages.
These needs are translated by the concept of amount
of useful heat or degree-days. Furthermore, the
optimum development and growth of plants is
around 30 °C. The temperature increase will result in
a reduction of the duration of development stages and
total cycle. For example, a maize crop cycle will be
shortened by approximately 6 days for a temperature
rise of +2 °C. All things being equal, a shorter cycle,
particularly in the reproductive and ripening phase,
results in a reduction in the number and size of grains
formed and a lower yield.
22
Figure 11: Maize yield trends in temperate and tropical
areas based on global warming (source André et al. 2003)
Recent studies of the CILSS/Agrhymet (Sarr et al.
2007, AGRHYMET, 2009) have shown that yields
of crops such as millet/sorghum will fall by over 10
% in the case of temperature increase of + 2°C and
insignificant rainfall variations in 2050 (Figure 12).
A + 3 °C increase in temperature will result in lower
crop yields of about 15 to 25 %
Simulations conducted across the globe (FAO, 2008)
show a relatively large decline (from 20 to 50 %)
in yields of cereal crops throughout the Sahel, from
Niger to Senegal in 2050 (Figure 14).
Figure 14: Projected impacts of climate change on the
potential of rainfed cereal production. Trends in 2050
compared to the average 1961 – 1990 (source FAO, 2008)
Figure 12: Rates of change in grain yields of millets/sorghums in Niger and Burkina Faso based on temperature
increase scenarios (Source B. Sarr et al. 2007)
S0_2020: 1 °C temperature increase;
S0_2050: 1.5 °C temperature increase;
S0_2080: 3 °C temperature increase;
For the 3 case scenarios, no change in rainfall compared
to the current period was considered.
According to this study, yields of cereal crops will
decline generally in the tropics and sub-tropics, while
increases are predicted in the high latitudes. Then,
developed countries in the middle latitudes would
still be winners in terms of productivity.
However, in the case of plants such as rice, whose
photosynthetic system adds value to somewhat higher
levels of CO2 in the atmosphere, a certain increase
in yields of about 10 to more than 35 % could be
observed over the next decades if water resources are
sufficient (Sarr et al., 2007, Keita, 2009). However,
in the longer term, the depressive effect of high
temperatures will offset the “fertilizing effect” of
CO2 and there will be reduced rice yields (Fig. 13).
Figure 13: Projected impacts of climate change on the
yields of three varieties of irrigated rice in Niger (adapted
from Keita, 2009)
23
On top of these negative physiological effects on
the agricultural production potential, there are
other factors also related to climate change such
as the degradation of soil quality resulting from
deforestation, erosion, salinization of coastal land,
groundwater and surface water due to the elevation
of sea level and water pollution.
Furthermore, the elevation of temperature is
favourable to increase the fertility and growth of crop
pests and extend their geographical areas.
Therefore, one would expect an expansion of arid
and semi-arid zones, a reduction in area suitable
for agriculture and agricultural production potential
thus making access to food more difficult throughout
the West Africa region, particularly the CILSS
countries.
Adapting farming practices to climate change
It is clear that the productivity losses resulting from climate change will exacerbate the already recurrent food
crises in the area. Thus, adaptation options on improving the resilience of farming systems through methods
and technologies for coping with this new climate factor have been undertaken. They are:
•
•
•
•
•
Redefinition of the agricultural calendars, playing on planting dates x cropping cycle of varieties to
better manage the rainfall variability,
Development of varieties adapted to water stress and/or heat,
Development of agricultural water management methods: water and soil conservation and crop
protection against extreme climate events, supplemental irrigation and pure irrigation from surface
water (rivers, ponds, retention basins, groundwater…)
Development of irrigated agriculture and diversification and intensification
Adoption of rational management methods of soil fertility etc…These adaptation measures have been
identified within the various National Action Programmes for Adaptation (NAPA).
24
Impacts on water resources
by Dr. Abou AMANI, Unesco
and
Dr. Abdou ALI, AGRHYMET
Regional Centre
According to the IPCC’s fourth Assessment Report, the annual river flow and water availability are expected
to diminish by 10 to 30% in some dry regions of the middle latitudes and in the dry tropics. According to the
same report, the poor communities will be most vulnerable because of their limited adaptive capacity and
high dependence on climate-sensitive resources such as water resources and agricultural production systems.
In Africa and by year 2020, between 75 and 250 million people will be exposed to water scarcity because
of climate change. Coupled with ever increasing demand, this situation will adversely affect livelihoods and
exacerbate water-related problems.
The prospect of climate change in West Africa is likely to exacerbate these challenges in terms of management
of water resources and hamper the improvement of livelihoods. Two documents were produced in the subregion and present the potential consequences and constraints and identify the strategies and concrete actions
to implement in West Africa’s river basins to cope with climate change. A summary of some of these actions
is presented below.
Overview of the main impacts of climate variability and change on water resources in West Africa
Several studies have been conducted on climate variability and water resources in West Africa. The studies
were based on long-term hydrological observations of the past sixty years and show a significant change in the
climate and hydrological regimes around the 70s, characterized by large variations, sometimes with continuous
deficits for over thirty years after this period.. The major changes recorded after the 70s are as follows:
•
•
•
•
•
•
•
A clear break in rainfall data and average flows observed around years 1968-1972, with 1970 as a
transitional year;
A general decrease in average rainfall of about 15% to 30% according to the zone;
A beginning of the season now highly variable and spread over in time.
A decrease in surface water resources in the major river basins (40 to 60%) resulting in drastic reduction
in the volume of water flowing through the major rivers, increasingly severe low-water levels with
frequent pauses in water flows, deficits in the filling of most reservoirs, with such attendant socioeconomic impacts as reduced level of water supplies for the cities
Intrusion of the salty tongue inside the coastal lagoons (lagoon of Cotonou, Senegal delta, etc.) and a
threat to freshwater biodiversity;
A significant reduction in area of major natural wetlands both on the continent and the coastal areas
with a consequent reduction in fish production;
For most aquifers, a lower level reduces groundwater in the major rivers, with saltwater intrusion in
coastal aquifers.
25
There are few studies on the future impact of climate change in West Africa from 2025 to 2050. The few
studies conducted show large uncertainties in current models with sometimes very sharp differences in the
projections. Research efforts are still needed in this area. However, it is accepted by the international scientific
community that extreme hydrological events (droughts and floods) will increase in the future. Even if we
don’t yet know the magnitude of the future changes, we should expect, for the sub-region, an increase in the
variability of water resources due to climate change; hence the need to act now.
Focus on the impact of climate change on river basins of Niger and Lake Chad
Niger River and Lake Chad are emblematic references which help to understand the impact of current
climate variability on water resources in the Sahel. The Niger basin, stretching from Chad to Guinea, helps
to illustrate the evolution of water resources in relation to climate change in the Sahel. Similarly, Lake Chad,
which is the major water body in the eastern part of the region, plays a key role in the Sahel. Changing flows
in the Niger basin, as well as the water level of Lake Chad are thus analyzed in this section.
Inter-annual evolution: the index of the annual module of the Niger river at Koulikoro (Mali) shows that
the water flow deficits continue in the Western part of the basin (Fig. 15-a). Since 1971, there has been only
one year (1999) when flows were above the inter-annual average of period 1905 – 2006. In contrast, some
stations in the South-East Basin, such as Lokoja, in Nigeria, show greater frequency of flows above the
average during the current period (after 1993). As for Lake Chad, the water body has started increasing over
the last years (Fig. 15-b). This evolution of water resources is consistent with that of rainfall.; which implies
that the impact of climate - in terms of rainfall – is dominant for large water systems in the Sahel. However,
the increase in flows in the South-East of the Niger Basin is more important than that of the rainfall. The
reason for this, as discussed below, is the impact of changes in the soil surface.
Intra-seasonal variability: The flows of the Niger River in Niger are considered in this section. They are
good representatives of flows of the middle basin. The hydrological regime of the Niger River in Niamey is
characterized by two floods. The first flood, called local flood, comes mainly from run-off from tributaries
of the right bank (especially those of the Sirba) and a flood, called Malian or Sudanian flood, coming from
run-off from the Upper Basin (Guinea and Mali). The local flood occurs during the rainy season (July to
September) while the Malian flood comes during the dry season (December to February). Mean hydrographs
are calculated for three characteristic periods: the wet period 1950 – 1970, the dry period 1971 – 1990 and
the current period 1991 – 2009.
The Malian flood continues with its downward trend that started with the major drought of the 70s. On the
other hand, the local flood is resuming more importantly, with flows, surpassing even those of the wet period
1950 – 1970. This return of the local flood is due to tributary flows from the right bank (Fig. 15-e). Rainfall
in this basin has not increased significantly. This improved flow is mainly due to higher run-off coefficients;
which demonstrates the importance of environmental change in these basins.
In short, the current flows are characterized by a rapid increase in early season and early withdrawal at the
end of season. It is therefore necessary to adopt a better strategy to respond and adapt to these changing
flows. The control of water, through medium and small-sized water retention structures, is a very credible
option in this regard.
26
a
b
c
e
d
Fig.15 a. Inter-annual trends in the Niger River flows at
Koulikoro and
b. Inter-annual trends (1998 to 2007) of the water body of
Lake Chad.
c. Comparison of average hydrographs of the Niger River in
Niamey
d. Monthly flow index of the Niger River in Niamey.
The months of June to September show a surplus compared
to the average 1950 – 2007.
e. Comparison of average flows of the Sirba River at the
Garbey-Kourou station for the three characteristic periods.
Concrete actions for better knowledge and management of climate variability and change and their
impacts on water resources
The multiplicity of plausible future climatic scenarios shows that what is important is the management of
variability and uncertainty. This implies improving our knowledge on climate and its impacts on water
resources. Concrete actions to put in place include:
•
•
•
•
•
Promoting collection of meteorological data and establishment of reliable information networks and
efficient management platform: case of HYCOS Projects;
Promoting research to remove uncertainties, like the AMMA Programme and the FRIEND-WCA
Project, among others. Assessing vulnerability and impacts of climate change on water resources,
wetlands and land degradation is essential for the implementation of effective adaptation measures;
Developing and promoting the use of decision-making tools for climate-related risk management.
Because of the wide variability of climate (at all scales) within the region, the PRESAO (Seasonal
Forecasting in West Africa) process established by the ACMAD-AGRHYMET-ABN consortium for
the prediction of rainfall and river flows must be strengthened to improve the quality of seasonal
forecasts for the sub-region.
Providing academic institutions and research institutes with technical and financial resources to
strengthen research in the field of modelling processes and their impacts;
Strengthening and improving training on vulnerability assessments and adaptation measures in the
water resource sector.
27
Concrete actions to adapt to climate change for resource management in West Africa at the basin
level.
The following generic and concrete adaptation actions can be considered, based on the analysis of the situation
in some basin organisations within the sub-region and elsewhere, for a given transboundary basin in West
Africa:
•
Establishment of an adequate legal and institutional framework in each transboundary basin:
. Legal status of the river, its tributaries and distributaries;
. Basin organisation;
. Basin Water Charter;
. Environmental Code.
•
Setting up of infrastructures (structural and secondary) for the control and development of water
resources;
•
Establishment of a modern monitoring network on water resources;
•
Establishment of a network on environmental and socioeconomic data collection;
•
Development of planning and forecasting tools that address climate change (database – GIS –
observatories – needs/resource trend chart);
•
Promotion of research/development works on adaptation to climate change;
•
Capacity building of stakeholders at national and sub-regional levels for greater awareness on climate
change and its effects;
•
Regional programmes to fight against invasive aquatic weeds, silting, river bank erosion, waterborne
diseases;
•
Measures to encourage the involvement of populations (micro finance, rural electrification, fish
farming, aquaculture, DWS, etc.);
•
Mechanism to mobilize financial partners;
•
Implementation of income-generating infrastructure.
Concrete actions, at policy and institutional levels, to adapt to climate change for resource management
in West Africa.
The major institutional priority measures recommended to increase the adaptability of West Africa in water
resource management are, amongst others:
•
•
•
•
•
•
•
•
Promote Integrated Water Resource Management. The current initiative on integrated water resource
management should be promoted at all levels (local, national and regional) because it is the best way to
manage depleting water resources in the region, while taking into account all related aspects. Also, the
shared nature of most river basins is one of many reasons for the adoption of IWRM strategy within
the sub-region.
Promote protection of wetlands;
Promote the United Nations Convention on the use of transboundary water for purposes other than
navigation;
Strengthen legal and regulatory measures to preserve water quality;
Mobilize financial and human resources for effective implementation of National Plans for adaptation
to climate change;
Take climate change into account in the feasibility studies of water and hydro-agricultural projects;
Urgently revisit the design standards of hydraulic structures developed in the 60s and which continue
to be used with all the risks about the resilience of such structures, despite the important ecological and
climate change observed in the sub-region and the prospect of future changes to come;
Take appropriate legal, regulatory and organisational action to mitigate the impacts of flooding whose
extent and frequency should increase with climate change.
Capacity building at different levels of the population and stakeholders on climate change is also necessary.
28
Impacts on pastoralism
According to the 4th International Panel on Climate Change (IPCC) report, the
anthropogenic origin of global warming is well established today (IPCC, 2007). It
is also established that livestock emit considerable amounts of greenhouse gases
through the digestion of large ruminants or composting of livestock excreta (Blaxter
and Clapperton, 1965).
by Issa GARBA, expert in
pastoralism, AGRHYMET
Regional Centre
Thus, livestock plays an important role in the rising tide of global warming.
Each year, ruminants emit 15% of the production of methane gas released into
the atmosphere (IPCC, 2001). Much of CH4 from farms is produced by ruminants
(cows, sheep…). Their digestive system includes a rumen allowing microbial
digestion of fodder and leading to the production of methane, then eructated by
the animal. These methane emissions vary by type of animal and its diet. Thus, the
dairy cow, the growing cattle, the sheep and the goat respectively produce 90, 65
and 8 Kg of methane per capita/year. As for non ruminants like the horse, the pig
and poultry, they produce respectively 18, 1 and 0.1 kg methane per capita/year
(Chouinard, 2004). However, it is important to note that these are measurements
taken in Western intensive breeding systems, therefore in a breeding system which
is different from the predominantly extensive Sahelian breeding systems.
Methane also comes from manure and slurry composed of dung. As any organic matter, these products are
decomposed by micro organisms: when manure is piled, the decomposition takes place in a low oxygen
environment, thus producing a large amount of methane; when manure is spread on the ground, the
decomposition is effected by contact with the air and most of carbon of the organic matter is decomposed into
carbon dioxide CO2 (INRA, 2009).
Furthermore, the variation in rainfall patterns has a negative impact on the environment in general and grazed
ecosystems in particular. The decrease in rainfall causes a problem of forage production and a lack of water
for livestock. In addition, the frequency of extreme events such as severe droughts will have many negative
impacts on the spatiotemporal dynamics of ponds, which occupy a strategic place in the Sahel in pastoral
societies. They are critical in the definition of transhumance routes and camp sites for pastors, and they
provide a leadership role in the ecosystem balance.
Pastoralism will be also affected by the effects of climate change due to declining production from pastures
in arid and semi-arid West Africa. This was the case of the 2008/2009 cropping season; because of the high
spatial and temporal variability of rainfall, it was observed in the countries of the Atlantic front (Senegal,
Mauritania) that fodder production had shown a large surplus, while in the other Sahel countries (Niger, Chad)
the result was negative (Figure 16).
Figure 16: Fodder production potentials for the season 2008/2009 in the Sahel countries
29
Satellite monitoring of the rainy season on the crop and pasture conditions has shown that the 2009 rainy
season was characterized by an upswing in Senegal, Mauritania, in western Mali and a major part of Burkina
Faso, with good fodder production confirmed by the joint CILSS-FAO-FEWS NET assessment mission of
October and November 2009. However, the situation is very deficient in Niger and deficient in Chad. For
example, fodder deficit in Niger is estimated at more than 16 million tonnes. This situation has led to sizeable
transhumance, characterized by massive movement of livestock to the coastal areas.
All these factors contribute to exacerbate conflicts between farmers and pastoralists. Moreover, this new
climatic environment would be conducive to the outbreak of climate-sensitive animal diseases. A study of
Seo and Mendelsohn (2006) has however shown that high temperatures would not affect small farmers raising
goats because of their resistance to heat.
30
Farmers’ perceptions of
climate vulnerability and
change
by Dr Hubert N’DJAFA OUAGA, AGRHYMET Regional Centre
The impacts of climate variability on the eco-social systems of the Sahel sub-region are clear. The sectors
most affected are Agriculture, through land degradation, livestock due to the reduction of vegetation cover and
water resources. Impacts on these sectors have significant negative consequences on the populations taking
into account the fact that the rural people make up 80% of the population, with agriculture and livestock as
the main development activities.
According to Burton, Huq et al., 2002; IPCC a. 2001, adaptation involves an adjustment within a human
system, in response to climatic stimuli or their present or future effects, including climate variability and
extreme events. Thus, adaptation is a process that is rooted in socialization, policy and social learning, and is
expressed through mechanisms and decisions to cope with climatic stress (Ader and kelly, 1999). Therefore, it
is not possible to implement an adaptation policy without taking into account the social context that surrounds
the local knowledge orlocal know-how.
Through the implementation of five (5) pilot projects of the “Capacity Building for Adaptation to Climate
Change in the Sahel” Project carried out by AGRHYMET/CILSS on CIDA financing, surveys on the pathways
for adaptation of the populations to climate change have been conducted on the issue of adaptation related
to agriculture, pastoralism and water resources. We present hereafter some results of these studies, which
illustrate the perceptions and practices regarding adaptation to climate variability and change.
31
People’s perception of the vulnerability and impacts of climate variability and change
The results of the general survey on the local people’s pathways for adaptation have helped highlight the
perceptions and practices of local communities as regards adaptation. The global assessment of climate change
by the populations is diverse and varied. Thus, changes in the physical and biological environmental observed
by the populations date back to the major droughts of 1973-74 and 1983-84 which particularly marked and
undermined the “Eco-socio system of the Sahel area”. These changes occur on the biophysical and agrobiological level on the one hand, and on the social level on the other hand.
On the biophysical and agro-biological level
Changes are manifested by severe thunderstorms, erratic rainfall, disturbance in the duration of the different
seasons of the year, planting periods, disappearance of temporary water points, degradation of plant resources,
gradual erosion of biodiversity, recurrent droughts, declining yields, change in the forage system, significant
changes in the physiognomy of the landscape and loss of wildlife.
On the social level
The impacts are felt at the level of household poverty, erosion of solidarity and social fabric, the loss of trust
and mutual distrust between and within communities.
Climate uncertainties have some impact on the dynamics of farming systems. When faced with climatic
hazards, the farmers react to preserve and maintain their livelihoods. Thus appeared practices to sustain and
maintain production systems in the areas of environment, land tenure security, crop and animal production,
organisation and community management of natural resources etc. To do this, the populations resort to
endogenous strategies or to strategies introduced by the technical services and development projects.
32
Local adaptation practices
by Hubert N’DJAFA OUAGA, AGRHYMET Regional Centre
Agricultural production sector
Farmers develop several coping strategies to address risks associated with climate variability (drought, winds,
crop pests etc.) that result in a decrease in agricultural and forage production. These coping strategies include
those relating to the control of farmland degradation, management of soil fertility, crop diversification, animal
production and sale of livestock, crop pest management, development of income-generating activities, rural
exodus, differential exploitation of space, etc.
Animal production sector
As climatic hazards intensify, transhumance of large amplitudes tends to disappear to make room for nomadism
of proximity and localized mobility is becoming more frequent. In Niger, localized mobility in time and space
was observed on the plateaus of the Department of Keita. In this area, sedentary pastors are developing this
strategy of localized mobility.
33
This strategy helps avoid conflicts with indigenous farmers and creates conditions of peaceful coexistence
between rural communities. Increasingly, we witness strengthening of surveillance of space and animals, herd
re-composition, de-stocking, a redefinition of the terms of grazing contracts and fodder stockpiling, improved
zoo technical performance through animal fattening and finally, , pasture planting (photo2)
In short, farmers have a good reading of the manifestations of climate variability and change. To that end,
they develop strategies to counter these climatic hazards. The question one may ask is: will these strategies be
enough to cope with extreme climate events?. Hence the need to properly assess the impacts of climate change
in order to suggest culturally, socially and economically based strategies.
Designing a half moon at Sandoube Kare, a site for the Fakara pilot project (Niger), 2005
Pasture seeding at Kajiki – Bouza, a site for the Tahoua pilot project (Niger), 2005
34
Focus on the “ Capacity Building
for adaptation to Climate Change
in the Sahel ” Project
With funding from the Canadian International Development Agency, CILSS through the AGRHYMET
Regional Centre has been implementing since 2002, the project on: “Capacity Building for Adaptation to
Climate Change in the Sahel”. THE MAIN EFFECT EXPECTED FROM THE PROJECT IS TO EVENTUALLY
REDUCE THE VULNERABILITY OF THE SAHELIAN POPULATION vis-à-vis the adverse effects of climate
variability and change. The overall objective is to build the capacities of the AGRHYMET Regional Centre
(ARC), to promote and develop the capacities of the countries and populations and to put in place, through
a participatory approach, pilot actions for adaptation in the fields of integrated water resource management,
pastoralism and soil fertility. AGRHYMET is supported, in this project, by national implementing agencies,
Environment Canada and the University of Quebec at Montreal. After the execution of this project:
i) the ARC regional thematic databases have been updated and their management improved;
ii) knowledge about agricultural productions and surface water resources have been updated;
iii) professionals from CILSS member countries have been provided training in study methodologies on
climate change (impacts, vulnerability, adaptation strategies);
iv) impacts of climate change on water resources and agricultural production have been assessed;
v) pilot adaptation projects have been implemented through participatory approach in the area of integrated
water resource management, pastoralism and soil fertility in close collaboration with the rural communities.
The pilot projects have helped achieve better understanding, across the region, of the various impacts and
measures put in place vis-à-vis past climate variability and then identify coping strategies that can be easily
implemented by the communities themselves.
35
This component which is part and parcel of the Project on: “Capacity Building for Adaptation to Climate
Change in the Sahel” actually began in late 2003. It consists of five (5) pilot projects based in Burkina Faso,
Mali and Niger (cf. Map below).
These pilot projects address the following issues:
In Burkina Faso:
•
Soil fertility management in a context of climate change on the central plateau of Burkina Faso;
•
Adaptation to climate change for the hydrological system of Sahelian rivers and watersheds of their
tributaries: the Sirba river as an example in Burkina Faso
In Niger:
•
Impact of climate change on pasture management in the Sahel and the relationship between pastoralists
and farmers in Tahoua (Niger);
•
Community management of grazing areas in a Sahelian and Sudano-Sahelian zone (CMG) in Fakara
(Niger)
In Mali :
•
Adaptation to climate change in the Central Delta of the Niger River in Mali
The implementation strategy is based on synergy of action between: Researchers – developers – Farmers. The
Table below summarizes all the implementing agencies involved in the execution of the pilot projects.
36
PILOT PROJECT AND IMPLEMENTING AGENCY
CENTRAL PLATEAU
1. Environmental and Agricultural Research Institute (INERA), scientific coordinator
2. Provincial Directorate of Agriculture, Water and Fishery Resources of Zondoma (DPAHRH)
3. Zandoma Inter Union of Naam Groups
4. Hydrogeology laboratory of the University of Ouagadougou, scientific coordinator
5. Directorate General of Water Resources Inventory (DGIRH)
6. Provincial Directorate of Agriculture, Water and Fishery Resources of Namentenga (DPAHRH)
7. Directorate of water resources (DRE) of Niger
CENTRAL DELTA
8. Institute of Rural Economy (IER) Mopti, scientific coordinator
9. Regional Directorate in Support of Rural Communities (DRAMR)
10. Regional Directorate of Hydraulics and Energy (DRHE)
11. Mopti Fishing Operation (OPM)
12 Mopti Rice Office (ORM)
TAHOUA
13. AGRHYMET Regional Centre, scientific coordinator
14. Cooperation for the Development of Emerging Countries (COSPE)
15. Union of Pastoralists/Farmers/Extension Workers/ Associations for the Promotion of Mutual
Assistance to Local Initiatives in Pastoral Areas, in short (UEP/APEL-PZ)
16. Regional Directorate of Agriculture Development (DRDA)
17. Regional Directorate of Animal Resources (DRRA)
I8. National Agronomic Research Institute in Niger (INRAN)
19. Abdou Moumouni University of Niamey
20. International Livestock Research Institute (ILRI)
FAKARA
21. International Crops Research Institute for the Semi-Arid Tropic (ICRISAT), scientific coordinator
OTHER PARTNERS
22. ARC Methods and Applications Unit (MAU)
23. ARC Regional Database and Software Engineering Unit – Communication and Public Relations Unit
24. ARC Natural Resource Management Unit
25. University of Quebec at Montreal (UQAM)
26. Sahelian Consultants
37
The mobilisation of Canadian expertise has been effective through the Chair of Studies of Urban Ecosystems
of the University of Quebec at Montreal (UQAM) and Environment Canada for the support to the component
on the comprehensive survey of farmers’ strategies (pathways) for coping with climate change.
Main results
•
•
•
•
•
•
•
•
•
•
•
A comprehensive survey (over 500 survey forms) on pathways for adaptation on the five (5) pilot
projects allowed creating a database in Access, and transferred under NVIVO for the qualitative
analysis and under SPSS for the quantitative analysis.
Inventory of local techniques for water and soil conservation and soil fertility management and
establishment of demonstration sites in collaboration with the populations for agro-pastoral
production;
Quantitative and qualitative Inventory of water resources in the watershed of the Sirba river;
Hydrological modelling of the Sirba watershed;
Diachronic mapping of land use of all sites;
Implementation of many sectoral studies;
Development of self-training manual on the UNFCCC and the protocol of Kyoto;
Establishment of the Information System on pilot projects;
Establishment of cooperation frameworks between and amongst stakeholders;
A documentary film on the pilot projects in Burkina and Niger;
Progressive monitoring-evaluation of pilot projects by CIDA;
38
Zoom on the African Monitoring of Environment for Sustainable Development
(AMESD) Programme. ECOWAS theme: Water Management for Crop and
Rangeland management (An African initiative to ensure appropriate and sustainable use of
natural resources)
The overall objective of this programme is to
improve environmental monitoring for better
natural resource management in the ECOWAS area
(including Mauritania and Chad) to reduce poverty
in one of the poorest areas of the planet.
More specifically, the aim is to implement and
execute the AMESD Programme in West Africa
to improve the capacity of the AGRHYMET
Regional Centre (ARC) and other national bodies
of the ECOWAS region (including Mauritania and
Chad) involved in environmental management, to
better use Earth observation data for better water
management and more efficient management of
crops and livestock.
Target groups
ECOWAS decision-makers and heads of regional
and national institutions and bodies, that have the
mandate of monitoring and managing environmental
resources such as water, agriculture and livestock,
as well as heads of structures involved in sectors
related to the environment, such as disaster
management.
Beneficiaries
The ultimate beneficiaries are the populations of the
region, who will benefit from more effective and
efficient decisions taken through the information
produced by the AMESD ECOWAS Programme.
Particular attention will be paid to the most
vulnerable populations living in rural and forested
areas and to groups most exposed to natural hazards.
The Programme will contribute to appropriate and
sustainable use of natural resources and therefore,
to more social and economic development and
poverty reduction.
Expected results
•
Information products and services to
improve the quantity and quality of
information for environmental monitoring
are developed within the ARC
•
Access to data from earth observation
of low and medium resolution in the
ECOWAS
countries
through
the
establishment of a database and its
39
•
•
dissemination via the EUMETCast
network and/or Internet is improved
ECOWAS decision-makers are informed
and sensitized in the use of Earth
observation data in making decisions on
environmental management
The capacity of AMESD partners in the
ECOWAS region (+ Mauritania and
Chad) as regards operational access
and use of data from earth observation
for environmental management is
increased; these partners include
institutions particularly active in the
region in the field of environmental
monitoring as well as national technical
services.
Main activities
•
Creation of a database/information
products within the ARC
•
Establishment of information services
for the dissemination of information
products via the EUMETCast network
and the Internet
•
Implementation of adaptation/validation
schemes of information products geared
to the West African context
•
Organisation of meetings for the
information/sensitisation of decisionmakers on the AMESD Programme’s
products and actions
•
Publishing and distribution of newsletters
and publications on the state of the
environment based on AMESD
products
•
Training of ARC and key regional
institutions’
staff
working
in
environmental monitoring in the use of
satellite data
•
Organisation of training/information
workshops on AMESD products in all
ECOWAS countries
•
Training of technicians from government
technical departments in the management
of data from the EUMETCast network
and use of AMESD products
Advertisement
A Master’s degree in Climate Change and Sustainable Development
The AGRHYMET Regional Centre (ARC), a
specialized institution of the Permanent Interstate Committee for Drought Control in the
Sahel (CILSS), is a centre of excellence for
training in agro-meteorology, hydrology, and
crop protection applied to food security, natural
resource management, and agricultural water
management.
ARC is also a WMO regional training centre, a
member of AUF and its diplomas are recognized
by CAMES. Its curricula are regularly reviewed
by a Scientific and Educational Board composed
of eminent scholars and teachers from the North
and the South.
From 1975 to date, the ARC has trained more
than 1000 senior professional staff from and
outside CILSS countries (Master students,
engineers, senior technicians).
CILSS vision on training issues
CILSS vision 2020 on the consequences of
climate change in the Sahel and in West Africa
is that climate change may accelerate the
phenomenon of droughts and floods, leading
to reduction of water resources, declining
agricultural yields, and increased prevalence
of crop diseases, etc.. This situation may
exacerbate food insecurity and poverty.
Therefore, climate change may be considered
as a serious and long-term issue whose effects
are not limited to just an environmental problem
today, but a socio-economic development and
sustainable development issue.
Objective of the Master’s programme
The aim is to train senior executives who
will be able, first, to use and capitalize on
knowledge in climate science for studies of
risk and vulnerability, impact, adaptation and
mitigation of climate change (CC) and secondly
to integrate climate change into action plans
and regional, national and local development
strategies.
Target group
The target group will consist of executive
staff from the CILSS/ECOWAS zone who are
working and have a professional experience in
the fields of environment, meteorology, agriculture,
water resources, forestry, energy, etc. And students
holding a master’s degree (maîtrise) or any other
diploma in disciplines related to environment
Organisation of the Master’s programme
The programme lasts 12 months and consists of:
5 compulsory modules:
-
Module 1: Global climate governance (2
weeks)
Module 2: Science of climate variability
and change (7 weeks)
Module 3: Vulnerability, impact and
adaptation of natural and human systems
to CC (7 weeks)
Module 4: Communication, management
(3 weeks)
Module 5: Climate change and sustainable
development (7 weeks)
Module 6: End-of-study dissertation (6
months) preferably in the countries of
origin
Supervision of the Master’s Programme
Supervision will be provided by experts of the
Agrhymet Regional Centre, experts from the
platform of institutions operating in the sector
of environment and Meteorology in Niamey
(PIREM), university teachers, executive staff
from the Ministries of Environment, Agriculture,
professional staff from the United Nations System,
the private sector, and NGOs, etc.
Funding
Funding is sought from CILSS financial and
technical partners
Rentrée: 11 octobre 2010
Contact
Director General AGRHYMET Centre
B.P. 11011, Niamey, Niger
Tel: +227 20 31 53 16; Fax: +227 20 31 54 35
E-Mail: [email protected] ,
[email protected]
Web Site: http://www.agrhymet.ne
Bibliographical references
AGRHYMET, 2009 : Proceedings of the workshop on the results of the “Capacity Building for Adaptation
to Climate Change in the Sahel” Project. Ouagadougou, 2-4 February 2009
André J. C. Cloppet E. 2003. Quel climat fera t’il demain. Agrobiosciences, Universités 18 p
CEDEAO-Club /Sahel/OCDE/CILSS. 2008. Climate and Climate Change. The Atlas on Regional
Integration in West Africa. Environment Series. Available at: « www.atlas-westafrica.org».
ENDA, UNESCO, ESI et NCAP, 2007: adaptation aux changements climatiques et Gestion des ressources
en Eau en Afrique de l’Ouest ; Rapport de synthèse. WRITESHOP, 21-24 February 2007. Dakar. Senegal.
FAO, 2008. Food Climate E-newsletter, Dec.14 p
IPCC, 2007: Climate Change 2007. Impacts, Adaptation and Vulnerability. Contribution of Working
Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, M.L. Parry,
O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press,
Cambridge, UK, 976 p.
Keita, C. O, 2009: Impacts potentiels du changement climatique sur la riziculture dans la vallée du bassin
du Niger moyen. Cas du périmètre de Saga. Mémoire de fin du cycle Mastère en Gestion concerté des
ressources naturelles, option GIRE. Centre Régional, AGRHYMET, Niamey, Niger.
Niasse, M., N, A. Afouda, A.Amani, 2004: Réduire la vulnérabilité de l’Afrique de l’ouest aux impacts du
climat sur les ressources en eau, les zones humides et la désertification. Eléments de stratégie régionale de
préparation et d’adaptation. UICN, gland, Suisse et Cambridge, Royaume Uni. XVIII + 71 pp.
N’Djafa O. H, 2005 : Rapport synthèse de l’enquête générale sur les itinéraires d’adaptation des populations
locales à la variabilité et aux changements climatiques conduite par AGRHYMET and UQAM, Niamey
2005 13 pages.
Sarr B. Traoré S. Salack S. 2007. Évaluation de l’incidence des changements climatiques sur les rendements
des cultures céréalières en Afrique soudano-sahélienne. Agrhymet, Regional Centre CILSS, Niamey.
UNFCCC. 2008. Index of NAPA Projects by Country available at: «http://unfccc.int/adaptation/least_
developed_countries_portal/napa_project_database/items/4583.php. National Action Plans for Adaptation
(NAPA) of 7 UEMOA member countries, excluding Côte d’Ivoire, which is not regarded as a least
developed country (countries not included in Annex I to the Convention.
•
Some publications avalaible on our
website: www.agrhymet.ne
Director of publication
Mohamed Yahya Ould Mohamed
MAHMOUD Director General of ARC
•
Editor in chief
Papa Oumar DIEYE,
Head of the CIDU
•
Editorial Board :
Dr Abdou ALI
Dr Abou AMANI
Dr Benoît SARR
Dr Hubert DJAFA OUAGA
M. Issa GARBA
Dr Seydou TRAORE
• Layout and electronic dissemination:
BOUBACAR Mainassara Abdoul Aziz
AGRHYMET special Monthly
B.P. 11011
Niamey, NIGER
Tel: (227) 20-31-53-16
Fax: (227) 20-31-54-35
Email: [email protected]
Web: http://www.agrhymet.ne
Regularly consult the AGRHYMET Regional
Centre’s Web site : www.agrhymet.ne
The primary source of information on training
and information centred on food security, water
management and desertification control in the
Sahel.
42