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Climate change. Why is it so important?

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(1)

Climate Change

Why is it so important?

Alain RIVAL Indonesia-France Seminar Makassar, Sulawesi December 1-3, 2014

(2)

What climatic changes are expected ?

1

2

3

Seasonal and

inter-annual variability Changes in

climatic trends

Extreme Climatic Events

(Bréda, 2014); thanks to Th Caquet

Photoperiodism in African sorghum: Flowering is

synchronous with

ending of rainy season

(3)
(4)

The average increase in temperature on the

surface of the earth from 1880 to 2012 was

approximately of :

• A. 0,85

0,2

C

Quizz

• A. 0,85

±

0,2

°

C

• B. 8,5

±

1,8

°

C

• C. 0,08

±

0,018

°

C

Answer:

A

(IPCC 2014)

(5)

Average yearly

temperatures

Changes in global average surface temperature

relative to 1961-1990 (APCC, 2013)

Decennial average

temperatures

(6)

Rising of sea level between 1901 and 2010 was

• A. 19 mm

Quizz

• B. 19 cm

• C. 1,9 mm

Answer :

B

(IPCC 2014)

(7)

Surface calorific content in oceans Average sea level 1900-1905

Evolutions in the ocean and cryosphere since

the early twentieth century (IPCC, 2013)

Surface calorific content in oceans (0-700m)

Average sea level 1900-1905

Extension of Arctic sea ice in

summer

(8)
(9)
(10)
(11)
(12)

The

Tropical

Climate

Hallé 2008 SUN Earth

• Earth to Sun distance

• Angle of incidence of the sun

• Day length (photoperiod)

• Diurnal temperature higher than the annual average amplitude

It is simplistic to say that the tropical climate is hot

(13)

Tendance du rendement du maïs en fonction de réchauffement

moyen

-5 0 5 10 V a ri a ti o n d e r e n d e m e n t e n % milieu tempéré milieu tropical

Global warming has not the same impact

on yields

-25 -20 -15 -10 0 1 2 3 4 V a ri a ti o n d e r e n d e m e n t e n % Réchauffement moyen en °C

(14)

Ceratophytum tetragonolobum (Bignoniaceae) P la n t b io m a ss p e r in d ivi d u a l (g ) P la n t b io m a ss p e r in d ivi d u a l (g ) +164% +164%

**

**

+62% +62% --11%11%

2

2

3

3

Under elevated CO

2

vines are likely to accelerate

tropical forest dynamics and reduce carbon stocks

CO CO22 concentration (ppm) concentration (ppm) P la n t b io m a ss p e r in d ivi d u a l (g ) P la n t b io m a ss p e r in d ivi d u a l (g ) 280 280 420420 560560 700700

0

0

1

1

J Granados & Ch Körner (2002) J Granados & Ch Körner (2002) Glob Change Biol 8:1109

Glob Change Biol 8:1109

(15)

Climate change and pathogens

Development of the coffee

rust is sensitive to

temperature and moisture

variations

Climate change and animal

vector-borne diseases.

Studies on risk of

transmission of Nile fever by

mosquitoes

(16)

Climate-Smart Agriculture

The basics

1. Sustainable increases in agricultural production

and farmers' income (food safety)

and farmers' income (food safety)

2. Adaptation (and resilience) to climate change

3. Mitigating climate change by reducing emissions

of greenhouse gases and carbon sequestration

(17)

Climate Smart Agriculture at work

In Niger: the natural regeneration of trees (agroforestry)

assisted by farmers

(18)

Tree cover in fields in Zinder, Niger

(19)

Agroforestry field in West Africa: corn and Faidherbia

« Evergreen agriculture »

(20)

Aerial view of agroforestry parkland dominated by Faidherbia

in Niger (ICRAF)

(21)

46% of agricultural land have more than 10% tree cover, 27% of agricultural land have more than 20% tree cover 15% of agricultural land have more than 30% tree cover 7.5% have more than 50% tree cover (Zomer et al, 2009)

(22)
(23)

Climate Smart Agriculture at work

Conservation agriculture

Three basic technical

principles:

Permanent soil cover

Minimal soil

disturbance (zero

disturbance (zero

tillage)

Crop rotation

Triple Win

Yields maintained for food security

Better soil management (adaptation)

Increased carbon in soil (mitigation)

(24)

Intercropping: a form of conservation agriculture

(25)

Five intercropping: A current situation in Africa

Banana, maize, cassava, beans, cabbage Uganda

(26)

Water

(27)

• Water behind dams quadrupled since 1960

• 3 to 6 times as much water in reservoirs as in natural rivers • Water withdrawals from rivers doubled since 1960

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