Climate Change: Its danger for our production and why it escapes our prediction

Prof. Kees Stigter, Agromet Vision
[Netherlands, Indonesia, Africa]
FISIP/RCCC (UI) Depok, 21 May 2015
Climate Change:
Its danger
for our production
and why it escapes
our prediction
1

I am making use of experience
collected together with
Prof. Yunita T. Winarto,
FISIP, UI, Depok,
her students and our groups
of farmers in Indramayu.
From that perspective this is
a joint presentation.
2

I am a visiting professor
in the Universitas Indonesia (UI)
Research Team on
Response Farming
to Climate Change,
Cluster for
Environmental Anthropology
Center for
Anthropological Studies
FISIP, UI 3

I am also
an affiliated professor
at the Agrometeorology Group,
Department of Soil, Crop and
Climate Sciences,
University of the Free State,
Bloemfontein, South Africa.
Under this nomination
I give Roving Seminars
in other African countries. 4

Our planet earth has a unique
but complicated climate
that presently is changing due to
the influence that our (mankind’s)
activities appear to have
on the composition
of its atmosphere.
It is called anthropogenic
(man made) climate change. 6

The world’s agricultural systems
face an uphill struggle
in feeding a projected
nine to ten billion people by 2050.
Climate change introduces a
significant hurdle in this struggle
7

There is general and widely held
scientific consensus
that the observed trends in
atmospheric & ocean temperature,
sea ice, glaciers as well as
climate extremes,
during the last hundred years,
cannot be explained solely
by natural climate processes
and so reflect human influences.8

The argument that
what we experience could be
natural climate change
can also be refuted by the fact
that present understanding
of cyclic climatology of the past
points to
a cooling planet
without the presence
of mankind. 9

On the simplest level,
the weather is
what is happening
in the atmosphere
at any given time.
The climate, in a narrow sense,
can be considered
as the “average weather”.
10

In a more scientifically accurate
way, it can be defined as:
“the statistical description
in terms of
the mean and variability
of relevant quantities
over a period of time”.
11

One may argue that
“global warming” is like “ageing”:
You can reduce the consequences
but it will continue to happen.
Stopping it is impossible,
so adaptation is necessary.
12

The issues are:
(i) global warming,
(ii) increasing climate variability,
(iii) more (and possibly more
severe)
meteorological and climatological
extreme events. 13

Is global warming real?
From worldwide observations
WMO (Geneva) concluded
a long time ago
that our planet is warming up.
This has to be considered a fact.
15

The warming up is not the same
everywhere because
(i) incoming solar radiation is
highest in the tropics
(ii) oceans (and to some extent
other large water bodies)
do influence what happens
in the lower atmosphere 16

Warming means
that the atmosphere
is gaining energy
in the form of heat.
From where?
The main source of energy
is the solar radiation.
17

IPCC (the Intergovernmental
Panel on Climate Change)
has been stressing,
with increasing confidence
over the years,
that the cause of this heat gain
is an increase
of greenhouse gases
in our atmosphere. 18

Our atmosphere gets
its energy from two sources:
(i) It is warmed from below
by solar energy absorbed
by the earth surface
during the day.
This heat gets distributed
throughout
the boundary layer. 20

We should here already indicate
the difference between
land and water surfaces.
On land, in daytime, a tiny surface
layer becomes much warmer,
with the very surface becoming
hottest, depending mainly
on water content. 21

In water the absorption
is over a certain depth,
decreasing with depth.
The water surface therefore does
not become very warm from
direct absorption, ocean currents
play
a more important role here. 22

We were talking of how the
atmosphere gains heat.
(ii) Its gases absorb
the longwave radiation
sent from the earth surface
throughout day and night.
This prevents the land surface
from overheating. 23

But indeed
most additional heat created is
absorbed by the oceans.
The large heat capacity
of water
prevents the oceans from
overheating.
24

We know this radiation loss
from a cooling surface
(and the cooling air due to this)
in nights without a cloud cover.
When there are clouds, they send
roughly as much longwave radiation
back to the
earth surface as they receive from
that surface, and no or appreciably
less cooling occurs. 25

So we must conclude that
our planet is actually
heating up mainly
because of this absorption
of radiative heat
by the greenhouse gases
in the atmosphere.
Increasing greenhouse gases
mean additional heating. 26

INTERLUDE
ON SOME DATA
AND WHAT
INFLUENCES THEM.
27

Somewhere near 1800
the carbon dioxide concentration
was something as 280 ppm,
while we have recently
reached 400 ppm.
It is presently increasing
exponentially.
28

From 1960 till 2010 the
temperature increase
is estimated to have been
less than a degree Celsius
(0.7 ºC, 0.85 ºC since 1880).
29

But the projection
for the next 50 years is in the
order of one degree Celsius,
with the emissions and
atmospheric contents kept
within the range
of the IPCC scenarios.30

Even if the concentrations
of all greenhouse gases
and aerosols
were kept constant
at year 2000 levels, a further
warming of about 0.1°C per decade
[so 0.5º C in fifty years]
would be expected.
31

It is generally accepted that,
if for this century
the temperature increase
can be limited to 2 ºC,
the damages will remain
much more limited than
when the scenarios give
a 4 ºC increase.32

What do such figures
mean in practice today?
Here is an example of Arabica coffee
grown on the slopes
of the Kilimanjaro, Tanzania.
Coffee is the world's most valuable
tropical export crop. 34

Recent studies predict
severe climate change impacts
on Coffea arabica (C. arabica)
production.
However, quantitative
production figures are necessary
to provide coffee stakeholders
and policy makers
with evidence to justify
immediate action. 35

Using data from the
northern Tanzanian highlands,
it was demonstrated that increasing
night time (Tmin) temperature was
the most significant climatic variable
responsible for diminishing
C. arabica yields
between 1961-2012.
36

The minimum temperature rose in that
half century
by between 1 and 1.5 °C.
The projection for the next 35 years for
that region is 1.5 °C.
With the minimum temperature
at 14 °C,
the yields were
about 500 kg beans per hectare. 37

A non-linear (sigmoid) model
constructed from data
from local areas with different
minimum temperatures
gave the following results:
38

With the night minimum rising
to 15 °C, the yields would become
about 450 kg ha-1.
With a night minimum temperature
at 16°C this decreases
to about 300 kgha-1.
39

While for 17°C
this becomes about 100 kgha-1.
This means a prediction
of average coffee production
diminishing to 145 kgha-1 by 2060
in those areas of Tanzania.
.
40

In the case of Arabica coffee,
a solution could be
to go to higher,
still colder grounds,
although this disrupts
living conditions
and biodiversity patterns.
41

The same has been observed
with apples in India.
The classical varieties must go
higher up,
while new more heat tolerant
varieties are sought
to replace them
at the lower heights.
42

But if we think
about the lowland tropics,
there is no way out
apart from crop diversification
and also here finding
more heat tolerant varieties.
But that is a lot more difficult.
The following data show
how bad the situation is. 43

Rice
Data obtained from a CGIAR
umbrella study, the same
as used for maize below.
44

Temperatures beyond critical
thresholds not only reduce
the growth duration
of the rice crop,
they also increase spikelet sterility,
reduce grain-filling duration,
and enhance respiratory losses,
resulting in lower yield
and lower-quality rice grain.
45

Rice is relatively more tolerant
to high temperatures
during the vegetative phase,
but highly susceptible
during the reproductive phase,
particularly at the flowering stage.
46

Unlike other abiotic stresses,
heat stresses occurring
either during the day or the night
have differential impacts
on rice growth and production.
47

High night-time temperatures
have been shown to have
a greater negative effect on rice yields,
with a 1 °C increase
above critical temperature (>24 °C)
leading to 10% reduction
in both grain yield and biomass.
48

High day-time temperatures
in some tropical and subtropical
rice growing regions
are already close to the optimum levels.
An increase in intensity and frequency
of heat waves coinciding
with sensitive reproductive stages
can result in serious damage
to rice production. 49

Here is one more example
Maize
The results are from something as
20.000 trials at 123 stations all over
the world
of CIMMYT (Columbia).
50

§ Increased temperature
significantly effects
maize yield (P < 0.01).
§ Possible gains in yield
with warming
at relatively cool sites.
51

§ Significant yield losses at sites
where temperatures commonly
exceed 30°C
(corresponding to areas
where the growing season average
temperatures are >23°C or
average maximum temperatures
are >28°C).
52

§ Daytime warming
is more harmful to yield
than night-time warming.
§ Drought increases
yield susceptibility to warming
even at cooler sites.
53

§ Under ‘optimal’ conditions
yield losses occur over ca. 65%
of the harvested area of maize.
§ Under ‘drought stress’
yield losses occur at all sites,
with a 1°C warming resulting in
at least a 20% loss of yield
over more than 75%
of the harvested area. 54

The climate predictions discussed
are long term ones,
of which knowing the trends
is an important issue for
adaptation to the consequences
of climate change,
food policies, crop planning,
variety breeding and screening,
as well as farming system
adaptations and modifications..55

This knowledge is of course also
important for extension policies
and all other planning related to
agriculture that has to be made
to face climate change.
For farmers these are important
issues that can be discussed
at “Science Field Shops” for
their long term decision making.56

For forestry,
the climate change-induced
modifications of frequency and
intensity of forest wildfires,
of outbreaks of insects and pathogens,
and of extreme events
such as high winds and dry spells,
may be more important than the
direct impact of higher temperatures
and elevated CO2. 57

Global warming is likely
to encourage northern expansion
of southern insects,
while longer growing seasons
are likely to allow more
insect generations in a given season.
Forests that are
moisture stressed are often more
susceptible to attacks by insects.58

Of equal importance are
the considerations of taking away
or adding “trees outside forests”.
Integrating all existing and new
landscape ecosystems into a complex
climate adaptation-oriented resilience
approach appears highly promising,
but also extremely demanding.
59

The ocean affects the rate
of climate change and is in turn
affected by it as well.
Global warming could alter inputs
of salt water, fresh water, oxygen,
nutrients and pollutants
with potentially large consequences
for marine ecosystems and species.
60

Changes in currents
would also influence
the recruitment of organisms
in coastal waters
and offshore waters.
61

It has for example been reported
that most of the decline
in the world’s
marine fishery landings in 1998
could be attributed to changes
in the Southeast Pacific,
which was severely affected
by El Niño.
62

What we further
need to know
63

The main source
of this increase
of carbon dioxide, methane
and nitrous oxide
appears to be
our activities on this planet:
e.g. electricity generation
from coal, cement production
and driving cars are presently
the main culprits.
64

As to carbon dioxide,
measurements show
that it has increased
from the start
of the industrial revolution,
but that changes in land use
have also played
an important role by
large scale cutting of
vegetation, including trees.
65

This is also why Indonesia
has become a large
contributor, by felling trees
(sinks of carbon dioxide)
in large scale
(mostly illegal) logging,
often planting palm oil trees
instead, with appreciably less
carbon dioxide absorption
per hectare.
66

It is interesting to note
that since the very end
of the previous century,
the rate of global warming
has reduced
by at least half
till something as one third
of the rate
in the last 50 years
of that previous century.
67

This has been baptized
“the hiatus”, a lack of
continuity in the up going
trend of global temperature.
So climate change rates
reduce.
Is this going to change our
thinking?
68

Our lack of knowledge and
understanding is best
illustrated with the
discussion on this present
global warming “hiatus”.
69

Some deny its very
existence
but accurate world wide
measurements and
comparisons
show that this “hiatus”,
is there,
since the late 90s.70

There have already been four
quantitative(!) reasonings of
full fledged explanations:
(i) more volcanic particles
in the atmosphere;
(ii) extremely strong
large scale western winds
in the Pacific;
71

(iii) much warmer water
being transported to deeper
layers of the ocean;
(iv) indeed being in a down
going phase of the Pacific
Decadal Oscillation and/or
another of such oscillations as
surface induced atmospheric
variations/imbalances.
72

It is likely that any of these
four explanations
may actually be involved,
if not more processes.
But we have no clue
about the ratios of their
contributions.
73

It is presently most likely that
the cause of this hiatus is indeed
more warmer water going
to deeper layers, resulting in a
(temporarily?) relatively cooler
ocean surface.
This also shows how important
oceanic surface temperatures
are for determination
of our climate.
74

Here we also have one of the
weakest rings in the chain of
climate predictions.
We know so much less
about how the sea surface
temperatures are determined
by currents and deep waves
than we understand on the
atmospheric resultants.75

Indeed, we have for decades
sent radiosondes with balloons
into the atmosphere, but
only very recently have buoys
been placed in the Pacific Ocean,
particularly in those parts used
for climate prediction purposes.
76

But if we look at the
predictions of the 2014/2015
weak El-Niño (I will explain),
it appears that the atmosphere
sometimes does not want
to behave the way we know it.
That makes the little
that is predictable suddenly
also unpredictable.77

Old players enter the scene
78

The El-Niño is a disturbance
of “normal” climatological
conditions for many
thousands of years.
It has nothing to do
(or had nothing to do)
with climate change.
79

Now scientists have learned that certain
Sea Surface Temperature (SST)
distributions in the Pacific Ocean
correspond with El-Niño phenomena,
which gives higher SSTs in these areas.
But El-Niño (meaning the “Christmas
child”) was known to the fishermen
of Peru for the cold water upwelling
occurring before their cost and giving
above normal catches of fish
around Christmas in some years.80

So it are unpredictable
ocean currents and deep waves,
that are not understood in
sufficient detail, that create the
surface signals
for El-Niño’s to occur.
They are very important in
short term climate predictions
(one to three months).81

The combined forces
of ENSO and global warming
are likely to have dramatic,
and currently largely unforeseen,
effects on agricultural production
and food security.
82

Agricultural production
in for example quite some
Sub-Saharan countries
is strongly influenced by
the annual cycle of precipitation
and year-to-year variations
in that annual cycle
caused by the
El Niño-Southern Oscillation
(ENSO) dynamics. 83

The ENSO actually can swing
beyond the “normal” state to
a state opposite that of El Niño,
with the trade winds amplified
and the eastern Pacific
colder than normal.
84

This phenomenon is often
referred to as La Niña.
In a La Niña year,
or when a La Niña period occurs,
many Asian regions,
such as Indonesia,
that are inclined toward drought
during an El Niño,
are instead prone to more rain.
85

Both El Niños and La Niñas vary
in intensity from weak to strong.
The intervals at which El Niños
return are not exactly regular,
but have historically varied
from two to seven/eight years.
Now, an El Niño can subside
into a “normal” pattern.
86

At other times
it gives way to a La Niña.
In many ways, the ENSO
cold phase
is simply the opposite
of the warm phase,
but without any symmetry
in durations or
severity/impacts. 87

This often holds true also
for the climate impacts of the two.
El Niño, or warm phase, tends
to bring drought to countries
like Indonesia and Australia,
at the west end of the Pacific.
88

The latter influences
in Africa
are so called tele-connections,
meaning that we don’t know
how or why!
89

But the strong influence
of La Niña
at the west end of the Pacific,
with abundant rainfall
and frequent floods,
among others in Indonesia,
does not have its parallel
in West Africa.
90

Now, it appears that the frequency
of these phenomena, and how they follow
each other, has changed in recent times!
However, we are not able
to simulate these actual changes
with the models that summarize
our understanding,
which at this moment
is still very insufficient.
91

As a consequence of the above,
simple growing season
rainfall scenarios
are very difficult
to derive from existing
raw or simplified (outlook fora!)
climate predictions.
92

93
Vulnerable communities,
across the world,
are already feeling the effects
of a changing climate.
These communities are urgently
in need of assistance
aimed at building resilience
to their new situations.

94
They are also in need of
undertaking climate change
adaptation efforts
as a matter of survival and
in order to maintain livelihoods.
In short: they are in need of
what we want to call an urgent
“agrarian/rural response
to climate change”.

One of the major problems
in guiding rural change,
in a rural response
to climate change,
is the low
formal level of education that
most farmers have
and for which governments
have done very little
to upgrade it. 95

But we need
improved climate literacy
among farmers
and a better trained extension
that can guide farmers
in further rainfall monitoring
and rainfall interpretation.
96

But we also need
further agro-ecosystem
observations, that,
with the rainfall distribution,
seasonal scenarios and results
from on-farm experiments
explain yields and
yield differences. 97

Since 2010, local farmers in
Indramayu, West Java, Indonesia,
were stimulated to measure
rainfall in their own plots,
on a daily routine basis,
using homemade
cylindrical rain gauges,
following routines
that were proposed earlier. 98

This has never been
a goal in itself.
It should now serve
other purposes
in a rural response
to climate change.
99

Climate change makes it
even more necessary to do
such measurements properly and with
high spatial measuring densities.
Doing this with an organized group
of well instructed farmers in a region
as part of an extension approach,
has the advantages that: 100

• each participating farmer
can create a record over the years
in a “climate logbook”;
101

• derivatives as monthly,
seasonal and annual totals,
maxima and minima,
can be easily obtained,
graphically compared
and understood as consequences of
climate realities.
102

• higher than usual measurement
densities can be obtained;
and
measurements can be compared
and discussed in (preferably)
monthly meetings;
103

• measurements can be part of a larger
extension routine in which other data
are collected as well;
and
measurements can serve as an input
to understanding yield differences
between areas, farmers,
seasons and years; 104

• measurements can form a basis for
attempts of adaptation to climate change,
particularly in relation to increasing
climate (including rainfall) variability
and the occurrence of more
(and sometimes more severe)
meteorological and climatological
extreme events
(including droughts, heavy rains
and floods). 105

This is the way a group of farmers,
organized in the
Indramayu Rainfall Observers Club
(IROC),
developed a new attitude
towards climate realities
in Indramayu region,
for the past five years.
106

This was already preceded
by more than two years
of comparable trials
in Gunung Kidul, Yogyakarta,
by a team of Prof. Yunita, myself
and groups of her students,
on which we published
a book in 2011. 107

This is all part
of a new extension approach
made necessary because
the Indonesian extension systems
have not or inadequately
been prepared
for the consequences
of a changing climate.
108

For the same reasons
we are now
extending this
to the island
of Lombok,
West Nusa Tenggara.
109

In addition to their daily rainfall
measurements, these rice farmers
do make and write down
agro-ecosystem observations
regarding sowing methods,
sowing/planting dates, crop varieties,
crop stages and development,
soil properties and soil moisture,
including irrigation situations
where applicable. 110

They also include pests and diseases
and their developments
(including measures they can take
in initial stages),
the results of fertilizer use
and pesticide use.
The observations made are noted down
on fact sheets that,
with the “climate logbook”,
form the historical farm plot records.111

After some time we started to use
these observations to predict yields
and after harvesting we discussed
whether yield and yield differences
could be understood
from these observations and the
monthly seasonal rainfall scenarios
that I deliver, as local climate
predictions, from raw NOAA and
IRA global/regional ENSO ones.112

Such “scenarios”
have this way been made
part of climate change
adaptation attempts
on the islands of Java and Lombok.
113

Two problems haunt
seasonal rainfall scenarios for
farmers to increase their resilience:
(i) skill of predictions
and
(ii) terminology chosen
for these monthly updated
seasonal rainfall predictions. 114

In February 2015, a questionnaire
was used to interview 42 farmers that
received the monthly seasonal scenario
regularly for six months or more,
and 42 farmers in the same villages that
did not receive these scenarios
as a control group.
Of those receiving these scenarios,
more than half received them
for more than two years and 85%
for more than a year. 115

Of the target group of farmers,
more than 93% received
the seasonal scenarios via SMS
on their mobile telephone,
while for more than 81% this was the only
way they received that information.
Of the number of farmers receiving
the seasonal scenarios,
55% understood them regularly or better
but 42% understood them
only sometimes. 116

This points to the necessity
to improve the scenario messages
as to the understanding required.
It could be observed
that those receiving the scenarios
for at least two years
had a much higher regular or better
understanding than the others. 117

Difficulties were mainly of two kinds:
(i) scientific terminology and
(ii) the use of “below normal, normal
and above normal” qualifications.
Our farmer facilitators had the role
of continuing to explain this,
but that has apparently been
insufficiently successful. 118

Of those farmers receiving the scenarios,
55% used them regularly or better
but 45% only sometimes or never
in their decision making.
The main reasons for not using
the scenarios are
that others make the farming decisions
(40% of those providing a reason)
or that rain is not their main
source of water
(26% of those providing a reason).119

For only 6% the scenarios were
not useful when followed.
Of those that used the scenarios,
84% was satisfied: regularly (16%),
often (28%) or always (41%).
Only 16% was satisfied only sometimes.
Of the many positive reasons
given for this satisfaction,
69% mentioned the high accuracy
of the scenarios and the positive role they
plaid in improving farmers’ anticipation.120

It appeared that
from the control group
not receiving our scenarios,
as well as from the main target group,
only less than 10% used (also)
other scenarios,
such as from MoA and BMKG,
in their decision making.
121

The above stories reveal
how we have started
to assist Indonesian farmers
to initiate a rural response
to recognized climate change.
Scaling this up into an as wide as
possible “farmer carried movement”
is the next stage we should aim at.122

The role of the government
through proper in-service refreshing
of extension and/or farmer trainers,
we have dealt with since 2008
in Roving Seminars at UGM & UI.
However, Indonesian Government
Departments/Institutes,
Farmers and Scientists live
in different worlds of their own.123

Climate Change: Its danger for our production and why it escapes our prediction

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