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UNDP Climate Change Country Profiles
Nigeria
A. Karmalkar1, C. McSweeney
1, M. New
1,2 and
G. Lizcano1
1. School of Geography and Environment, University of Oxford.
2. Tyndall Centre for Climate Change Research
http://country-profiles.geog.ox.ac.uk
General Climate
Nigeria, a country in West Africa, lies within the tropical zone and enjoys a truly tropical humid
climate, which is dominated by West African monsoon system. Nigeria experiences two seasons: a
wet season from April through October and a dry season from November through March. In the wet
season, moisture-laden south westerly wind from the Atlantic brings cloudy and rainy weather,
whereas in the dry season, the dry north easterly wind from the Sahara (harmattan) bring dusty and
fair weather. The prevalence of these alternating winds over the country influences is linked to the
movement of the Inter-Tropical Convergence Zone (ITCZ) north and south of the equator.
There are, however, wide variations in climate in different regions of the country with topographic
relief being a major factor. Seasonal mean temperatures throughout Nigeria are consistently over
20こC with diurnal variations more pronounced than seasonal ones. In general, temperatures are
lower in the wet season than in the dry season, and vary little from the coast to inland areas.
The wettest month in Nigeria is June in southern and the wettest area is the east coast, parts of
which receive over 4000 mm rainfall annually. Regions along the coast in western Nigeria receive
about 1800 mm rainfall annually, which decreases to about 500-1000 mm in central and northern
Nigeria.
Recent Climate Trends
Temperature
Mean annual temperature averaged over Nigeria has increased by around 0.8こC between
1960 and 2006, at an average rate of 0.18こC ヮWヴ SWI;SW (Table 1, Fig. 1).
Nigeria
Daily temperature observations show statistically ゲキェミキaキI;ミデ デヴWミSゲ キミ デエW aヴWケ┌WミI┞ ラa けエラデげ ;ミS けIラノSげ ミキェエデゲく TヴWミSゲ キミ デエW aヴWケ┌WミI┞ ラa けエラデげ1
;ミS けIラノSげ2 days are not statistically
significant.
o TエW ;┗Wヴ;ェW ミ┌マHWヴ ラa けエラデげ days per year in Nigeria has increased by 73 (an additional
20% of days) between 1960 and 2003 (Table 2). The rate of increase is seen most
strongly in SON.
o TエW ;┗Wヴ;ェW ミ┌マHWヴ ラa けcoldげ ミキェエデゲ ヮWヴ year in Nigeria has decreased by 45 (an
additional 12.4% of nights; Table 2). The rate of increase is seen most strongly in SON.
Precipitation
Mean rainfall over Nigeria shows a statistically decreasing trend of 3.5 mm per month (1.8%)
per decade between 1960 and 2006 (Table 1, Fig. 3). Trends in other seasons are not
statistically significant.
There are insufficient daily rainfall records available to identify statistically significant trends
in daily rainfall extremes.
GCM Projections of Future Climate
Temperature
The mean annual temperature is projected to increase by 1.1 to 2.5こC H┞ デエW ヲヰヶヰゲが ;ミS ヱく4
to 4.6こC by the 2090s (Table 1, Fig. 2). The range of projections by the 2090s under any one
emissions scenario is around 1-ヲこCく TエW ヮヴラテWIデWS ヴ;デW ラa ┘;ヴマキミェ キゲ ゲキマキノ;ヴ デエヴラ┌ェエラ┌デ デエW year, but warming is higher in northern Nigeria compared to the southern parts of the
country (Fig. 2).
All projections indicate substantial increases in the frequency of days and nights that are
IラミゲキSWヴWS けエラデげ キミ I┌ヴヴWミデ Iノキマ;デWく o Annually, projections indicate that the frequency of けエラデげ S;┞ゲ will increase from
about 11% during the period 1970-1999 to 18-49% of days by the 2060s, and 23-73%
of days by the 2090s. Days that are hot for each season are projected to increase
most rapidly in JJA from 11.5% to 34-98% of days by the 2090s (Table 2, Figs. 7, 8).
o Nキェエデゲ デエ;デ ;ヴW IラミゲキSWヴWS けエラデげ aラヴ デエW ;ミミ┌;ノ Iノキマ;デW ラa ヱΓΑヰ-99 are projected to
increase from about 11% to 32-60% of nights by the 2060s and 37-74% of nights by
the 2090s. Nights that are hot for each season are projected to increase most rapidly
in JJA, occurring on 55-99% of nights by the 2090s (Table 2, Figs. 9, 10).
1 けHラデげ S;┞ ラヴ けエラデげ ミキェエデ キゲ SWaキミWS H┞ デエW デWマヮWヴ;デ┌ヴW W┝IWWSWS ラミ ヱヰХ ラa S;┞ゲ ラヴ ミキェエデゲ キミ I┌ヴヴWミデ Iノキマ;デW ラa デエ;デ ヴWェキラミ ラヴ season.
2 けCラノSげ S;┞ ラヴ けIラノSげ ミキェエデ キゲ SWaキミWS ;ゲ デエW デWマヮWヴ;デ┌ヴW HWノラ┘ ┘エキIエ ヱヰХ ラa S;┞ゲ ラヴ ミキェエデゲ ;ヴW ヴWIラヴSWS キn current climate of that
region or season.
Nigeria
o TエW ヮヴラテWIデWS キミIヴW;ゲW キミ デエW aヴWケ┌WミI┞ ラa けエラデげ S;┞ゲ ;ミS けエラデげ ミキェエデゲ is generally
higher in the southern part of Nigeria compared to the northern part of the country
(Figs. 8, 10).
All projections indicate decreases in the frequency of days and nights that are considered
けIラノSげ キミ I┌ヴヴWミデ Iノキマ;デWく TエWゲW W┗Wミデゲ Sラ ミラデ ラII┌ヴ ;デ ;ノノ H┞ デエW ヲヰ90s in projections from
most of the models (Table 2, Figs. 11-14).
Precipitation
Projections of mean annual rainfall from different models in the ensemble are broadly
consistent in indicating a small increase in rainfall for Nigeria (Table 1, Fig. 3-6). Projected
changes in precipitation, however, show wide variations across the country (Figs. 4, 6).
Annual projections vary between -18 to +17% by the 2090s with ensemble median changes
of +1 to +4%. Seasonal median projections indicate decreases in rainfall in DJF and MAM and
increases in JJA and SON.
The proportion of total rainfall that falls in heavy3 events increases in most model
projections, changing by -4% to +13% by the 2090s (Table 3, Figs. 15, 16).
Maximum 1-day and maximum 5-day rainfalls tend to increase slightly in model projections,
changing by -1 to +20mm and by -6 to +30mm respectively by the 2090s. Model projections
are more variable in JJA and SON seasons (Table 3, Figs. 17-20).
Additional Regional Climate Change Information
A lack of consistency between models in representing the Inter-Tropical Convergence Zone
(ITCZ) and monsoon processes contributes to uncertainty in estimates of future precipitation
in this region (Christensen et al., 2007).
It is important to note that projections discussed in the report are based on climate models
with coarse spatial resolution, which hampers their ability to simulate regional-scale climate
features of the region.
For further information see Christensen et al. (2007) IPCC Wラヴニキミェ Gヴラ┌ヮ I ‘Wヮラヴデぎ けThe
Pエ┞ゲキI;ノ SIキWミIW B;ゲキゲげ, Chapter 11 (Regional Climate Projections): Sections 11.2 (Africa).
3 A けHW;┗┞げ W┗Wミデ キゲ SWaキミWS ;ゲ ; S;キノ┞ ヴ;キミa;ノノ デラデ;ノ ┘エキIエ W┝IWWSゲ デエW デエヴWゲエラノS デエ;デ キゲ W┝IWWSWS ラミ ヵХ ラa ヴ;キミ┞ S;┞ゲ キミ I┌ヴヴent the climate
of that region and season.
Nigeria
Methods and Documents
This report provides basic analyses of observations and climate model data in the form of narrative,
S;デ; デ;HノWゲが ;ミS ェヴ;ヮエキIゲ ;ゲ ;ミ さラaa デエW ゲエWノaざ ヴWゲラ┌ヴIW ;ミS I;ミ HW Iラミゲ┌ノデWS キミ キミ┗Wゲデキェ;デキラミゲ ラa climate impacts, risk assessments, or adaptation options and for use in further research. It is
important to note that significant limitations and caveats are involved wherever climate model
projections are applied. Please refer to the following documents for additional information.
Rationale and Methodology: McSweeney, C., G. Lizcano, M. New, X. Lu, 2010: The UNDP Climate
Change Country Profiles. Bull. Amer. Meteor. Soc., 91, 157に166. doi: 10.1175/2009BAMS2826.1
http://journals.ametsoc.org/doi/pdf/10.1175/2009BAMS2826.1
Technical details: http://country-profiles.geog.ox.ac.uk/UNDPCCCP_documentation.pdf
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Data Summary
Table 1
Observed
Mean
1970-99
Observed
Trend
1960-2006
Projected changes by the
2030s
Projected changes by the 2060s Projected changes by the
2090s
Min Median Max Min Median Max Min Median Max
Temperature
ふこCぶ
(change in
こC ヮWヴ decade)
Cエ;ミェW キミ こC Cエ;ミェW キミ こC Cエ;ミェW キミ こC
A2 0.6 1 1.2 1.5 2.1 2.4 2.5 3.7 4.6
Annual 26.2 0.18* A1B 0.4 1.1 1.4 1.6 2.1 2.5 2.3 3.1 3.9
B1 0.5 0.9 1.3 1.1 1.6 1.9 1.4 2.1 2.8
A2 0.5 0.9 1.6 1.4 2.3 2.8 2.4 3.9 5.4
DJF 24.9 0.1 A1B 0.3 0.9 1.7 1.4 2.1 3.2 2.3 3.2 4.1
B1 0.4 0.8 1.6 0.9 1.7 2.1 1.5 2.2 2.8
A2 0.5 1.1 1.4 1.4 2.1 2.6 2.5 4 4.6
MAM 28.9 0.21* A1B 0.6 1.1 1.3 1.5 2.1 2.5 2.4 3.2 4.3
B1 0.4 1 1.3 0.9 1.7 1.9 1.5 2.3 3.2
A2 0.5 0.9 1.3 1.4 1.9 2.3 2.7 3.5 4.5
JJA 25.6 0.22* A1B 0.4 1.1 1.4 1.6 2 2.6 2.3 2.9 4.1
B1 0.3 1 1.3 1.1 1.5 1.9 1.4 1.9 2.8
A2 0.5 0.9 1.3 1.4 2 2.4 2.4 3.6 4.5
SON 25.4 0.21* A1B 0.4 1.1 1.5 1.5 2.1 2.5 1.9 2.9 3.8
B1 0.4 0.9 1.6 1.1 1.5 2 1.3 2 2.6
Precipitation
(mm per
month)
(change in
mm per
decade)
Change in mm per month Change in mm per month Change in mm per month
A2 -3 0 8 -11 1 6 -23 3 13
Annual 95.8 -1.1 A1B -2 0 6 -10 0 7 -13 1 16
B1 -5 0 4 -5 1 6 -11 3 8
A2 -2 0 2 -2 0 2 -3 0 9
DJF 7.8 0.6 A1B -2 0 2 -3 0 3 -4 0 9
B1 -2 0 2 -2 0 1 -2 0 6
A2 -14 0 9 -13 -3 17 -31 -4 9
MAM 74.2 -1.8 A1B -6 -1 14 -23 0 14 -18 -1 15
B1 -7 0 11 -19 -1 8 -11 -2 11
A2 -11 1 8 -32 1 19 -44 2 35
JJA 196.6 -3.5* A1B -9 2 12 -21 0 19 -40 0 38
B1 -18 0 7 -15 2 28 -41 6 27
A2 -4 5 17 -5 2 15 -33 11 24
SON 104.8 1 A1B -8 1 11 -13 4 13 -20 5 20
B1 -12 4 15 -2 4 13 -2 7 20
Precipitation (%)
(mm per
month)
(change in %
per decade)
% Change % Change % Change
A2 -2 0 7 -9 1 6 -18 4 13
Annual 95.8 -1.1 A1B -2 0 6 -8 1 7 -10 1 17
B1 -4 0 4 -6 1 7 -8 3 8
A2 -28 -3 26 -41 -2 15 -51 -5 55
DJF 7.8 7.3 A1B -25 -3 18 -51 -3 28 -45 -5 37
B1 -30 -6 11 -32 -6 15 -31 0 27
A2 -10 0 12 -10 -3 13 -22 -3 11
MAM 74.2 -2.5 A1B -6 -1 14 -16 0 13 -14 -2 14
B1 -6 0 15 -12 -1 10 -9 -2 8
A2 -5 1 4 -16 1 10 -19 1 18
JJA 196.6 -1.8* A1B -7 1 5 -9 0 9 -19 0 19
B1 -9 0 3 -7 1 13 -18 3 12
A2 -4 4 11 -5 2 10 -20 10 21
SON 104.8 1 A1B -5 1 9 -8 4 11 -12 6 21
B1 -7 3 12 -3 4 9 -3 5 14
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Table 2
Observed
Mean
1970-99
Observed
Trend
1960-2003
Projected changes by the
2030s
Projected changes by the 2060s Projected changes by the
2090s
Min Median Max Min Median Max Min Median Max
%
Frequency
Change in
frequency
per decade
Future % frequency Future % frequency
Frequency of Hot Days (TX90p)
A2 **** **** **** 24 29 46 34 40 73
Annual 10.7 0.99 A1B **** **** **** 24 29 49 31 35 67
B1 **** **** **** 18 24 38 23 28 51
A2 **** **** **** 31 38 53 41 57 73
DJF 9.9 0.29 A1B **** **** **** 26 39 52 41 48 67
B1 **** **** **** 18 33 41 30 35 54
A2 **** **** **** 34 44 60 46 60 82
MAM 11.5 1.86 A1B **** **** **** 32 43 61 40 52 81
B1 **** **** **** 26 35 50 30 40 61
A2 **** **** **** 30 43 78 47 66 98
JJA 11.5 1.6 A1B **** **** **** 31 44 84 44 53 97
B1 **** **** **** 24 37 69 34 42 86
A2 **** **** **** 33 44 72 45 60 90
SON **** **** A1B **** **** **** 31 44 76 39 54 87
B1 **** **** **** 26 33 64 33 41 78
Frequency of Hot Nights (TN90p)
A2 **** **** **** 38 52 60 63 69 74
Annual 13.9 4.55* A1B **** **** **** 37 50 60 54 66 71
B1 **** **** **** 32 38 51 37 47 62
A2 **** **** **** 31 43 52 50 69 86
DJF 12.6 2.61* A1B **** **** **** 30 42 57 41 58 67
B1 **** **** **** 23 34 43 27 41 49
A2 **** **** **** 43 61 66 70 75 85
MAM 13.6 4.90* A1B **** **** **** 42 60 64 61 72 77
B1 **** **** **** 41 50 57 44 60 69
A2 **** **** **** 60 75 87 89 96 99
JJA 13.3 4.69* A1B **** **** **** 62 74 91 76 90 99
B1 **** **** **** 45 55 78 55 71 90
A2 **** **** **** 51 61 69 65 83 87
SON 15.5 6.95* A1B **** **** **** 51 65 72 61 78 83
B1 **** **** **** 39 45 62 47 55 74
Frequency of Cold Days (TX10p)
A2 **** **** **** 1 2 3 0 0 1
Annual 9.6 -0.51 A1B **** **** **** 1 2 3 0 1 2
B1 **** **** **** 2 4 5 1 2 3
A2 **** **** **** 0 2 3 0 0 2
DJF 11.7 1.32 A1B **** **** **** 0 2 3 0 1 2
B1 **** **** **** 1 3 7 0 2 4
A2 **** **** **** 0 2 4 0 1 2
MAM 9.9 -0.64 A1B **** **** **** 1 2 3 0 1 2
B1 **** **** **** 1 3 4 1 2 4
A2 **** **** **** 0 1 4 0 0 1
JJA 8.2 -1.59* A1B **** **** **** 0 2 3 0 1 1
B1 **** **** **** 0 2 4 0 1 3
A2 **** **** **** 0 2 5 0 1 3
SON 9 -1.12 A1B **** **** **** 0 2 4 0 1 2
B1 **** **** **** 2 3 5 0 2 4
Frequency of Cold Nights (TN10p)
A2 **** **** **** 0 2 3 0 0 1
Annual 7.5 -2.82* A1B **** **** **** 0 2 3 0 1 1
B1 **** **** **** 2 3 4 0 2 3
A2 **** **** **** 0 0 1 0 0 0
DJF 8.5 -2.42* A1B **** **** **** 0 0 2 0 0 0
B1 **** **** **** 0 1 4 0 1 2
A2 **** **** **** 0 1 3 0 0 1
MAM 7.4 -2.77* A1B **** **** **** 0 1 2 0 1 3
B1 **** **** **** 0 2 4 0 1 5
A2 **** **** **** 0 0 1 0 0 0
JJA 7.8 -2.51* A1B **** **** **** 0 0 0 0 0 0
B1 **** **** **** 0 0 1 0 0 1
A2 **** **** **** 0 1 3 0 0 1
SON 6.6 -3.17* A1B **** **** **** 0 1 4 0 0 4
B1 **** **** **** 2 2 5 0 1 3
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Table 3
Observed
Mean
1970-99
Observed
Trend
1960-2006
Projected changes by the
2030s
Projected changes by the
2060s
Projected changes by the
2090s
Min Median Max Min Median Max Min Median Max
% total rainfall falling in Heavy Events (R95pct)
%
Change in %
per decade
Change in % Change in %
A2 **** **** **** -3 2 7 -4 1 13
Annual **** **** A1B **** **** **** -2 1 7 -1 1 12
B1 **** **** **** -3 1 4 -3 2 8
A2 **** **** **** -18 -1 7 -20 0 15
DJF **** **** A1B **** **** **** -23 0 10 -26 -2 12
B1 **** **** **** -7 0 6 -18 0 9
A2 **** **** **** -5 2 7 -2 2 12
MAM **** **** A1B **** **** **** -5 1 7 -6 0 10
B1 **** **** **** -3 1 7 -2 2 9
A2 **** **** **** -3 2 8 -4 0 16
JJA **** **** A1B **** **** **** -3 2 11 -4 1 15
B1 **** **** **** -4 2 6 -3 2 10
A2 **** **** **** -2 1 9 -6 4 14
SON **** **** A1B **** **** **** -5 1 6 -3 3 10
B1 **** **** **** 0 1 7 -1 4 10
Maximum 1-day rainfall (RX1day)
mm
Change in
mm per
decade
Change in mm Change in mm
A2 **** **** **** 0 1 12 0 2 20
Annual **** **** A1B **** **** **** 0 1 13 0 3 19
B1 **** **** **** 0 1 9 -1 1 16
A2 **** **** **** -2 0 1 -2 0 1
DJF **** **** A1B **** **** **** -2 0 1 -2 0 1
B1 **** **** **** -1 0 0 -1 0 0
A2 **** **** **** -2 1 2 -1 1 7
MAM **** **** A1B **** **** **** -3 0 4 -4 0 5
B1 **** **** **** 0 0 2 0 0 2
A2 **** **** **** -2 1 10 -2 1 17
JJA **** **** A1B **** **** **** -2 1 13 -1 2 19
B1 **** **** **** -1 0 7 -1 1 14
A2 **** **** **** 0 1 10 0 2 17
SON **** **** A1B **** **** **** -2 0 6 -1 1 20
B1 **** **** **** 0 1 8 -1 1 8
Maximum 5-day Rainfall (RX5day)
mm
Change in
mm per
decade
Change in mm Change in mm
A2 **** **** **** -1 4 15 -6 4 25
Annual 128.7 -4 A1B **** **** **** -6 0 17 0 4 30
B1 **** **** **** 0 2 11 -2 2 18
A2 **** **** **** -4 0 3 -4 0 5
DJF 1.5 0.2 A1B **** **** **** -4 0 2 -5 0 3
B1 **** **** **** -3 0 2 -2 1 3
A2 **** **** **** -3 1 8 -4 1 15
MAM 12 1.18 A1B **** **** **** -4 0 8 -6 0 14
B1 **** **** **** -1 0 3 -4 0 6
A2 **** **** **** -9 3 14 -12 0 23
JJA **** **** A1B **** **** **** -11 0 17 -11 3 21
B1 **** **** **** -3 2 10 -4 2 17
A2 **** **** **** -5 1 15 -10 6 19
SON **** **** A1B **** **** **** -5 1 10 -3 3 33
B1 **** **** **** -2 2 11 -1 4 15
* indicates trend is statistically significant at 95% confidence
**** indicates data are not available
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Figure 1: Trends in annual and seasonal mean temperature for the recent past and projected future. All values shown are anomalies, relative to the 1970-1999 meanclimate. Black curves show the mean of observed data from 1960 to 2006, Brown curves show the median (solid line) and range (shading) of model simulations ofrecent climate across an ensemble of 15 models. Coloured lines from 2006 onwards show the median (solid line) and range (shading) of the ensemble projections ofclimate under three emissions scenarios. Coloured bars on the right-hand side of the projections summarise the range of mean 2090-2100 climates simulated by the15 models for each emissions scenario.
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Figure 2: Spatial patterns of projected change in mean annual and seasonal temperature for 10-year periods in the future under the SRES A2 scenario. All values areanomalies relative to the mean climate of 1970-1999. In each grid box, the central value gives the ensemble median and the values in the upper and lower cornersgive the ensemble maximum and minimum.
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Figure 3: Trends in monthly precipitation for the recent past and projected future. All values shown are anomalies, relative to the 1970-1999 mean climate. SeeFigure 1 for details.
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Figure 4: Spatial patterns of projected change in monthly precipitation for 10-year periods in the future under the SRES A2 scenario. All values are anomalies relativeto the mean climate of 1970-1999.See Figure 2 for details.
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Figure 5: Trends in monthly precipitation for the recent past and projected future. All values shown are percentage anomalies, relative to the 1970-1999 mean climate.See Figure 1 for details.
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Figure 6: Spatial patterns of projected change in monthly precipitation for 10-year periods in the future under the SRES A2 scenario. All values are percentageanomalies relative to the mean climate of 1970-1999.See Figure 2 for details.
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Figure 7: Trends in hot-day frequency for the recent past and projected future. See Figure 1 for details.
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Figure 8: Spatial patterns of hot-day frequency for 10-year periods in the future under the SRES A2 scenario. See Figure 2 for details.
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Figure 9: Trends in hot-night frequency for the recent past and projected future. See Figure 1 for details.
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Figure 10: Spatial patterns of hot-night frequency for 10-year periods in the future under the SRES A2 scenario. See Figure 2 for details.
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Figure 11: Trends in cold-day frequency for the recent past and projected future. See Figure 1 for details.
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Figure 12: Spatial patterns of cold-day frequency for 10-year periods in the future under the SRES A2 scenario. See Figure 2 for details.
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Figure 13: Trends in cold-night frequency for the recent past and projected future. See Figure 1 for details.
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Figure 14: Spatial patterns of cold-night frequency for 10-year periods in the future under the SRES A2 scenario. See Figure 2 for details.
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Figure 15: Trends in the proportion of precipitation falling in ’heavy’ events for the recent past and projected future. All values shown are anomalies, relative to the1970-1999 mean climate. See Figure 1 for details.
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Figure 16: Spatial patterns of projected change in the proportion of precipitation falling in ’heavy’ events for 10-year periods in the future under the SRES A2 scenario.All values are anomalies relative to the mean climate of 1970-1999. See Figure 2 for details.
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Figure 17: Trends in maximum 1-day rainfall for the recent past and projected future. All values shown are anomalies, relative to the 1970-1999 mean climate. SeeFigure 1 for details.
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Figure 18: Spatial patterns of maximum 1-day rainfall for 10-year periods in the future under the SRES A2 scenario. All values are anomalies relative to the meanclimate of 1970-1999. See Figure 2 for details.
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Figure 19: Trends in maximum 5-day rainfall for the recent past and projected future. All values shown are anomalies, relative to the 1970-1999 mean climate. SeeFigure 1 for details.
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Figure 20: Spatial patterns of projected change in maximum 5-day rainfall for 10-year periods in the future under the SRES A2 scenario. All values are anomaliesrelative to the mean climate of 1970-1999. See Figure 2 for details.