Upload
ngokhue
View
217
Download
3
Embed Size (px)
Citation preview
.
EDITORIAL TEAMChief EditorMr.. Ifeanyi D. Nnodu (Director/Weather Forecasting Services)Associate EditorJoseph E. Alozie (General Manager/Climate Services)Contributing AuthorsMr. Francis Dekaa Principal Climatologist Mrs. Agatha O. Anokwu Senior Meteorologist Mr. Paul A. Ugbah Senior Meteorologist Final EditingJoseph E. AlozieJohn OyegadeMaimuna BornuPublisherDr. Anthony C. AnuforomDirector General / CEONigerian Meteorological Agency (NiMet)National Weather Forecasting & Climate Research CentreNnamdi Azikiwe International AirportAbuja NigeriaISSN: 2315-9813© 2014 NiMet
PrefaceThe Nigerian Meteorological Agency (NiMet), in exercise of its mandate as enshrined in its Act, has produced this 1st Quarter edition of the Quarterly Weather Review 2014. The publication covers the period: January – March 2014, and discusses the typical weather and climate variable from the eye of the synoptic weather developments, temperature and rainfall variations, and socio-economic implications in some of the key sectors of the economy. The publication is intended to document the weather and climate conditions
1
THE NIGERIAN METEOROLOGICAL AGENCY
Issue No: 025 March 2014
QUARTERLY WEATHER REVIEW
JANUARY, FEBRUARY and MARCH 2014
during the period in review, noting that it will form a good reference material for students, researchers, MDAs and the general public.
In January 2014, the Inter-Tropical Discontinuity (ITD) hovered around 7.5DegN, thus leaving a large part of the country under the northeasterly winds. The southwesterly winds were restricted to the south of this region. Daytime temperatures ranged 28 – 37DegC, rose gradually and reached 42DegC in March 2014. At night, the temperatures rose from a range of 8.4 – 27.1DegC in January, and closed on 23 – 27DegC in March. The lowest value recorded during the season was 5.0DegC over Kano in January. The day was warmer than long-term average in January and March, while many parts of the south were colder-than-average in March 2014.
The migration of rainfall from the south to the north was very minimal during the period, as most of the rainfall events were restricted to the south of the country. On the rainfall departures from normal, we are closely monitoring the southeast and parts of the southwest as above normal rainfall has been reported in the areas during this first 3 months. These conditions portend drier situations particularly in the immediate inland areas though it is too early to worry about. It is hoped that the information contained in this edition will meet the expectations of the public and serve as a resource material for scientists and policy makers.
Table of ContentPreface 3
1.0 JANUARY 20141.1 Synoptic Features 71.2 Temperatures 91.2.1 Maximum temperature 91.2.2 Minimum temperature 10
2
1.2.3 Mean temperature 11 1.3 Rainfall 111.4 Socio-economic impacts 14 1.4.1 Agriculture sub-sector 151.4.2 Health sub-sector 161.4.3 Environment sub-sector 161.4.4 Water Management sub-sector 16
2.0 FEBRUARY 20142.1 Synoptic Features 172.2 Temperatures 192.2.1 Maximum temperature 192.2.2 Minimum temperature 202.2.3 Mean temperature 21 2.3 Rainfall 21 2.4 Socio-economic impacts 24 2.4.1 Agriculture sub-sector 242.4.2 Health sub-sector 242.4.3 Environment sub-sector 242.4.4 Water Management sub-sector 24
3.0 MARCH 20143.1 Synoptic Features 253.2 Temperatures 273.2.1 Maximum temperature 273.2.2 Minimum temperature 283.2.3 Mean temperature 29 3.3 Rainfall 293.4 Socio-economic impacts 33 3.4.1 Agriculture sub-sector 33 3.4.2 Health sub-sector 333.4.3 Environment sub-sector 333.4.4 Water Management sub-sector 34 3.5 ENSO Update 343.6 Summary and Conclusion 36
1.0 JANUARY 2014
1.1 Synoptic FeaturesThe Synoptic features during the Month of January 2014 (figure 1) comprise the following;
3
The Equatorial Trough over Nigeria was placed at 1010-1014hPa on the average, while the average pressure value at the center of Azores High ranged 1025 - 1030hPa
Fig 1: Some synoptic charts showing the key features in January 2014
The average pressure values at the center of St. Helena for the month was 1023.7hPa. This shows initial intensification and then weakening of the of the St. Helena high pressure belt throughout the month. The average position of the Inter-Tropical Discontinuity (ITD) for the month was 7.5ᵒN. This implies that the major part of the country was under the influence of the dry northeasterly winds which carry harmattan dust, leaving the moist south westerly grazing the coastal regions occasionally.
1.2 Temperatures
1.2.1 Maximum TemperaturesThe Month of January experienced maximum temperatures in the ranged between 28.0 – 37.0°C across the country (Fig. 2a). The lowest maximum temperatures of between 28.0 and 32.0°C were recorded over Katsina, Kano, Nguru, Zaria, Bauchi Gombe and Jos in the North, Benin and Eket in the southern part of the country. Most of the southern part of the country recorded the highest maximum temperature values in the ranged 32.0 – 35.0°C. The highest maximum temperature range of between 35.0 –37.0°C were observed over Yelwa, Bida, Minna, Abuja, Lafia, Lokoja, Makurdi, Ibi, Yola, Ogoja and Awka.
4
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Abj
Ado_EAkr
Asa
Aw k
BauB id
Bni
CalEkt
Enu
G om
G us
Iba
Ibi
I-O deIkj
Iko
Ilr
Ise
Jos
Kad
Kan
Kat
Laf
Lok M kd
M na
N gu
O goO nd
O sh
O w e
Phc
Pot
Sha
Sok
UyoW ar
Yel
Yol
Zar
28
32
35
37
Latit
ude
(N)
Longitude (E)
Legend
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Abj
AkrAsa
Awk
BauBid
Bni
Cal
Enu
Gom
G us
Iba
Ibi
I-OdeIkj
Iko
Ilr
Ise
Jos
Kad
Kan
Kat
Laf
Lok M kd
M na
Ngu
O goO nd
Osh
Owe
Phc
Pot
Sha
Sok
UyoW ar
Yel
Yo l
Zar
-3.5
-1.5
-0.5
0.5
1.5
2.5Legend
Wa
rme
rC
old
er
Norm
al
Latit
ude
(N)
Longitude (E)
I
MOIS
DR
Fig2a: January 2014 maximum temperature trend Fig 1b: Deviation of January maximum temperature
from long-term average
From figure 2b, the deviation of the maximum temperature from long-term average show that greater part of the country experienced warmer than normal condition, with Nguru, Yola, Katsina, Gusau, Zaria, Kaduna and Shaki being warmer than normal by more than 1.5°C during the month under review. However, normal conditions were observed over Sokoto and Abuja in the North, Ikom, Uyo, Port Harcourt, Ibadan, Abeokuta, Ijebu-Ode, Ondo and Ikeja in the South, while maximum temperatures over Benin and its environs where observed to be colder than normal. 1.2.2 Minimum TemperaturesThe minimum temperature values during the month generally ranged from 8.4 – 27.1oC across the country (Fig. 3). Lowest minimum temperatures between 8.0 – 1.6°C were observed over Katsina, Kano, Nguru, Potiskum,
Zaria, Bauchi and Jos. FIGURE 3: JANUARY 2014 MINIMUM TEMPERATURE FIGURE 4: DEVIATION OF MINIMUM TEMPERATURE FROM LONG-
TERM AVERAGEMost part of the country experienced minimum temperature ranged between 16.0 – 23.0°C, while places such as Ibadan, Abeokuta, Ijebu-Ode, Ikeja, Benin, Warri and Eket recorded minimum temperature values of greater than 23.0°C during the month.
5
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Abj
Ado_EAkr
Asa
Aw k
BauB id
Bni
CalEkt
Enu
G om
G us
Iba
Ibi
I-O deIkj
Iko
Ilr
Ise
Jos
Kad
Kan
Kat
Laf
Lok M kd
M na
N gu
O goO nd
O sh
O w e
Phc
Pot
Sha
Sok
UyoW ar
Yel
Yol
Zar
28
32
35
37
Latit
ude
(N)
Longitude (E)
Legend
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Abj
AkrAsa
Awk
BauBid
Bni
Cal
Enu
Gom
G us
Iba
Ibi
I-OdeIkj
Iko
Ilr
Ise
Jos
Kad
Kan
Kat
Laf
Lok M kd
M na
Ngu
O goO nd
Osh
Owe
Phc
Pot
Sha
Sok
UyoW ar
Yel
Yo l
Zar
-3.5
-1.5
-0.5
0.5
1.5
2.5Legend
Wa
rme
rC
old
er
Norm
al
Latit
ude
(N)
Longitude (E)
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Ab j
Ado_EAkr
Asa
Awk
BauB id
Bn i
CalEk t
Enu
Gom
G us
Iba
Ibi
I-O deIkj
Iko
Ilr
Ise
Jos
Ka d
Kan
Kat
La f
Lo k M kd
M na
Ngu
OgoO nd
Osh
Ow e
Phc
Po t
Sha
Sok
UyoW ar
Ye l
Yo l
Za r
8
16
23
27.5
Latit
ude
(N)
Longitude (E)
Legend
2 4 6 8 10 12 14
4
6
8
10
12
14
A B
AB
AKA O
A S
B A
B D B E
B I
C B
E B
EK
E N
G U
IB
IJIK
IK
IL
IS
IS
JA
JO
KA
K N
K T
LA
LO
M A
M I
M K
N G
O GO N
O S
O T
O W
P H
P T
S H
S O
U YW R
Y E
YL
ZA
A B
AB
AKA O
A S
B A
B D B E
B I
C B
E B
EK
E N
G U
IB
IJIK
IK
IL
IS
IS
JA
JO
KA
K N
K T
LA
LO
M A
M I
M K
N G
O GO N
O S
O T
O W
P H
P T
S H
S O
U YW R
Y E
YL
ZA
-5-4 .5-4-3 .5-3-2 .5-2-1 .5-1-0 .500.511.522.533.544.5
Co
ole
rNo
rmal
Wa
rme
r
To le ra nc e = ±0.5De g C
Tre nd o f m inim um te m p e ra ture in J a nua ry 2014
A comparison of the month’s minimum temperatures with the long term averages showed that warmer than normal conditions were dominant over most part of the northeast and southwest (figure 4). Colder than normal conditions were experienced over places such as Kano, Lokoja, Enugu, Awka and Owerri. Normal minimum temperature conditions were however, observed in and around places such as Sokoto, Nguru, Potiskum, Jos, Abuja, Ogoja, Uyo, and Calabar during the month.
1.2.3Mean TemperatureMean temperature departures from long term normal showed colder than normal conditions over only Kano and its environs. Normal conditions were however observed over Sokoto, Jos, Abuja, Lokoja, Makurdi, Ogoja, Enugu, Awka, Owerri, Uyo, Calabar, Port Harcourt and Iseyin. The remaining greater part of the country had warmer than normal conditions, Gusau, Kaduna, Shaki and Oshogbo being the warmest by between 1.5 – 2.5°C (figure 5).
Fig5: Deviation of January mean temperature from long-term averages
1.3 RAINFALLRainfall amount was observed to be above 65.0mm only in the coastal areas of the South, affecting places such as Ondo, Benin, Warri, Ikeja and Eket, with Eket recording the highest rainfall amount of 101.4mm. Other places in the country which recorded rainfall amount of up to 20mm were Yelwa, Akure, Asaba, Awka Calabar and Port Harcourt. As expected, there was no rainfall in the north, while the inland of the South had rainfall amount of between 0.0 – 10mm as shown in Fig.6.
6
2 4 6 8 10 12 142
4
6
8
10
12
14
Ab e
Abj
AkrAsa
Awk
BauBid
Bni
Cal
Enu
G om
G us
Iba
Ibi
I-O deIkj
Iko
Ilr
Ise
Jos
Kad
Kan
Kat
Laf
Lok M kd
M na
N gu
O goO nd
O sh
O we
Phc
Pot
Sha
Sok
U yoW ar
Yel
Yo l
Zar
-2.5
-1.5
-0.5
0.5
1.5
2.5
Latit
ude
(N)
Longitude (E) Co
lde
rW
arm
er
Norm
al
Fig6: January rainfall trend Fig7: January rainfall departure from long-term normal
The deviation of rainfall in the month from the long term values showed drier than normal rainfall conditions over the eastern flank of the country, especially over Ikom, Uyo and Owerri, where the rainfall was less than the long term mean by between 10.0 - 25.0mm (Fig. 8). However, the coastal areas of Ikeja, Ondo, Benin and Warri had excess rainfall amount compared to the long term mean by 50-75mm. Little or no difference in rainfall amount was observed over Sokoto, Gusau, Zaria, Kaduna, Ilorin, Jos, Makurdi and Ijebu-Ode when compared to the long term mean in the month under review.
1.3.1 Information on rainfall amount, departure from long term average and rain days for some selected stations is as presented in Table 3 below.
Table 1: A table containing information on some cases of heavy rainfall January.City Rainfall
(mm) Long term mean rainfall(mm)
Rainfall Departure from Long term mean(mm)
Rain days
Warri 89.3 24.0 65.3 7Yelwa 40.0 00.0 40.0 2Akure 30.1 10.3 19.8 4Ondo 78.7 07.5 71.2 7Calabar 24.8 28.6 -3.8 1Port Harcourt 57.2 19.4 37.8 2Ikeja Lagos 90.7 16.0 74.7 5
From Table 1 above, it is observed that the coastal areas such as Lagos, Ondo, Warri and Port Harcourt recorded significant rainfall amount in the
7
2 4 6 8 10 12 14
4
6
8
10
12
14
A B
A B
A KA O
A S
B A
BD B E
B I
CB
E B
E K
E N
G U
IB
IJIK
IK
IL
IS
IS
JA
JO
KA
K N
K T
LA
LO
M A
M I
M K
NG
OGON
OS
OT
OW
P H
P T
S H
SO
UYW R
Y E
Y L
ZA
0
10
20
30
40
50
60
70
80
90
2014 JANUARY RAINFALL TREND
Rainfall amount in mm
month compared to the January climatological mean. Warri, Ondo, Ikeja and Akure recorded the highest rain days of 7, 7, 5 and 4 respectively during the month.
1.4 SOCIO-ECONOMIC IMPACTS
1.4.1 AgricultureDry season farming was favoured during the month as a result warm and slightly humid conditions particularly in the south and central parts of the country. Products such as tomatoes, pepper, onions and vegetables were known to be in abundance during the period..
1.4.2 HealthThe warmer-than-normal day and night especially in the Northeast and parts of the North West created less comfortable conditions. The harmattan was also pronounced during the period. The north experienced moderate-severe cases of heat-related ailments such as meningitis, measles and chickenpox. Fig8: Cases of reported measles outbreak in January
(Source: Weekly Epidemiology Report, FMH, Vol.4 No.1 January 2014)
As shown in figure 8, this was most pronounced in the northern part of the country.
1.4.3 EnvironmentThe period was prominent with dust outbreak for various times. It shares the peak harmattan period with the preceding month, that is, December 2013. The ITD’s mean position of about 7.5DegN favoured the prevalence of dust particles raised from the source region and carried into the country in the dominant northeast winds, into the larger parts of the month. A few disruptions in flight movements were noted.
1.4.4 Water ManagementThe early rains in the southernmost parts of the country in January favoured the availability of water for all uses in the areas. There was however an increased migration of animal headsmen down-south in search of water for their animals. The community clashes in many parts of the south was a
8
result of these movements and the attendant destruction of farmlands by the animals.
2.0 FEBRUARY
2.1 Synoptic FeaturesThe Equatorial trough over the country in February came down slightly from its position in the previous month, and was located at an average 1009 - 1012hPa. The average pressure values at the center of Azores High was 1027hPa, showing a steady intensification of the Sub-Tropical pressure belt compared to the previous month. The St. Helena reached an average value of 1024.0hPa, indicating a slight intensification compared to January. The mean position of the ITD was 8.3oN, slightly moving up from its position during
Fig9a & b: The ITD position in February 2014 and weather activities were restricted to the southernmost parts
January (figure 9a). These implies that from the beginning to the end of the month places along the coast of south east were under Zone C weather conditions with thunderstorm activities. About seven (7) vortices transversed the country during the month.
2.2 Temperatures
2.2.1 Maximum TemperaturesMaximum temperature in the range 35.0 – 39.0°C were observed across the country during February. The lowest values in the range of 29.0 – 32.0°C were recorded over Jos and Eket while many southern cities such as Ado-Ekiti, Usi-Ekiti, Akure, Ondo, Ijebu-Ode, Oshodi, Ikeja, Benin, Warri, Owerri, Umuahia, Uyo, Port Harcourt and Calabar and a great portion of the north recorded temperature values in the range of 32.0 – 35.0°C. The highest range of values, that is, 35.0 – 39.0DegC occurred in the middle of the country (figure 10).
9
2 4 6 8 10 12 142
4
6
8
10
12
14
A BK
AB E
AB U
A D O-E KIT IA K U
A S A
A W K
B A U
B EN
B ID
CA L
EK E
E NU
G OM
G US
IBA
IB I
IJEIKE
IK O
ILO
IS E
JO S
KA D
KA N
K AT
LAF
LO K
M IN
MA K
NG U
O GOON D
OS H
O SH D
OW E
P HC
PO T
SH A
S OK
US I
UM UUY OW AR
Y EL
YO L
ZA R
N
Lo ngitu de (E)
Latit
ude (
N)
ITD
DRY W INDS
MOIST W INDS
Fig 11: Deviation of February maximum temperature from long-term average
From figure 11, the deviation of the maximum temperature from long- term average show that most part of the country experienced normal conditions. Some parts of Sokoto, Iseyin, Akure Ondo, Akure, Ijebu-ode, Ikeja, Benin, Warri and Calabar were colder than normal while Minna, Shaki and Iseyin in northern Oyo State were warmer than normal during the month.
2.2.2 Minimum Temperatures The minimum temperatures in the month generally ranged from 13.6 – 25.0oC across the country. The lowest range of 11.0 – 16.0oC were recorded in Jos, Kano and their environs. Cities like Enugu, Abakaliki and their environs recorded temperatures in the range of 16.0 – 21.0oC. the southern areas recorded minimum night temperatures in the range of 21.0 – 27.0oC during the month.
10
2 4 6 8 10 12 142
4
6
8
10
12
14
ABE
ABU
AKUASA
AW K
BAU
BEN
BID
CAL
EN U
G O M
G US
IBA
IB I
IJEIKE
IKO
ILO
ISE
JO S
KAD
KAN
KAT
LAF
LO K
M IN
M AK
N G U
O G OO N D
O SH
O W E
PH C
PO T
SH A
SO K
UYOW AR
YEL
YO L
ZAR
-1.8
-0 .8
-0 .5
0.5
0.8
1.4
LA
TIT
UD
E (
N)
LONGIT UDE (E )
War
mer
tha
n n
orm
alN
orm
alC
old
er t
han
nor
mal
LEG END
N
2 4 6 8 10 12 142
4
6
8
10
12
14
ABK
ABE
ABU
ADO -EK ITIAKU
ASA
AW K
BAU
BEN
BID
C AL
EKE
EN U
G O M
G U S
IBA
IB I
IJEIKE
IKO
ILO
ISE
JO S
KAD
KAN
KAT
LAF
LO K
M IN
M AK
NG U
O G OO N D
O SH
O SH D
O W E
PH C
PO T
SHA
SO K
U SI
U M UU YOW AR
YEL
YO L
ZAR
29
32
35
39
LEGEND
N
Longitude (E)
Latit
ude
(N)
2 4 6 8 10 12 142
4
6
8
10
12
14
ABE
ABU
AKUASA
AW K
BAU
BEN
BID
CA L
ENU
GO M
GU S
IBA
IBI
IJEIKE
IKO
ILO
ISE
JOS
KAD
KAN
KAT
LA F
LO K
M IN
M AK
NG U
OG OO ND
O S H
O W E
PH C
PO T
SH A
SO K
UY OW A R
YEL
YO L
ZAR
-5
-2 .5
-1 .5
-0 .5
0.5
1.5
2.5
War
mer
than
nor
mal
Norm
alCo
lder
than
nor
mal
LEGEND
LATI
TUDE
(E)
LONGITUDE (E)
N
2 4 6 8 10 12 142
4
6
8
10
12
14
AB K
AB E
AB U
AD O -E K IT IAK U
AS A
AW K
BA U
BE N
BID
CA L
EK E
EN U
G OM
G US
IB A
IB I
IJEIK E
IK O
ILO
IS E
JO S
KA D
KA N
KA T
LA F
LO K
M IN
M A K
NG U
O GOO N D
O SH
O SH D
O W E
PH C
PO T
SH A
SO K
US I
UM UUY OW A R
YE L
YO L
ZA R
LEGEND
LATI
TUDE
(N)
LO NGITUDE (E)
N
Fig10: maximum temperature trend
F
Fig 12: minimum temperature trend Fig13: Deviation of minimum temperature from
long-term averageFrom figure 13, the deviation of minimum temperature from long-term mean shows warmer than normal in parts of the northeast, northwest, few part of north central and southwest. The warmest nights were over Gusau and Maidugurii axis. Cities like Kano, Jos, Minna, Bida, Iseyin, Lokoja, Enugu, Awka, Ogoja, Owerri and Calabar Nguru observed colder than normal conditions, while minimum temperatures were normal over the rest part of the country during the month. 2.2.3Mean TemperatureFrom Figure 14, mean temperature departure from long term average map shows that greater part of the country experience normal condition (white background). Warmer than normal departures were observed in parts of the northeast, some part of northwest, extending to Shaki and Oshogbo in the southwest. Kano, Lokoja, Makurdi, Enugu, Akure, Iseyin, Owerri and Calabar however, experienced colder than normal temperatures. Fig 14: Deviation of February 2014 mean Temperature from long-term average
2.3 Rainfall Rainfall amount ranging from 0.2–132.3mm was recorded in Bauchi, Ilorin, Lokoja, Mambilla Plateau and most parts of the South. Most of the rain occurred in Eket and its environ that recorded the highest rainfall, range of 60.0 -135.0mm while the rest of the south recorded 10.0 – 60.0mm of rainfall(Fig. 15).
11
2 4 6 8 10 12 142
4
6
8
10
12
14
ABE
ABU
AKU
BEN
BID
CAL
EKE
ENU
IBA
IKE
IKO
ILO
ISE
KAT
LOK
MIN
MAK
OGOOND
OSH
OW E
PHC
SHA
SOK
UYOW AR
YOL
-20
0
100
200
300
420
Latit
ude (
N)
Longitude (E)
N
0
LEGEND
No
rma
lA
BO
VE N
OR
MA
L R
AIN
FALL
2 4 6 8 10 12 142
4
6
8
10
12
14
AB K
AB E
AB U
AD O -E KITIA K U
A S A
AW K
BA U
BE N
B ID
CAL
EK E
ENU
G O M
G US
IB A
IB I
IJEIK E
IK O
ILO
IS E
JO S
KA D
KA N
KA T
LAF
LO K
M IN
MA K
N G U
O G OO N D
O S H
O S HD
O W E
PH C
PO T
SHA
SO K
USI
UM UU YOW A R
YE L
YO L
ZA R
Dutse
B oko
-10
10
30
60
90
140
LATI
TUDE
(N)
LO NG ITUDE (E)
LEGEND
0
N
2 4 6 8 10 12 142
4
6
8
10
12
14
A B E
AB U
A K UAS A
AW K
B AU
BE N
BID
CA L
E NU
G O M
G US
IB A
IB I
IJEIKE
IK O
ILO
ISE
JOS
K AD
K A N
K AT
LAF
LO K
M IN
M AK
NG U
OG OO ND
O S H
O W E
PHC
PO T
S HA
SO K
UYOW A R
Y EL
Y O L
ZA R
-2.5
-1.5
-0.5
0.5
1.5
LATI
TUDE
(N)
LO NG ITUDE (E)
LE GEND
Col
der t
han
norm
alN
orm
al
Warm
er tha
n norm
al
N
Fig 15: February Rainfall Trend Fig 16: Rainfall Departure in February
The rainfall departure from long term-average shows that greater part of the country experienced normal condition. Above normal conditions prevailed over very few areas like Abuja, Ilorin, Lokoja, Abeokuta, Ibadan, Calabar and Eket (figure 16).
2.3.1 Information on rainfall amount, departure from long term average and rain days for some selected stations is as presented in Table 2 below
Table 2: A table containing information on some cases of heavy rainfall February.City Rainfal
l (mm)Long-term means (mm)
Departures from long-term means (mm)
Raindays
Akure 48.2 36.0 12.2 3Benin 53.3 44.1 09.2 4Calabar 61.6 53.6 08.0 3Ibadan 57.7 38.0 19.7 4Ijebu Ode 48.8 35.8 13.0 2Ikeja Lagos 32.5 32.2 -0.3 4Ilorin 29.6 9.5 20.1 1Uyo 35.8 42.1 -6.3 4
The table above shows that reasonable rainfall was recorded mostly in parts of the southeast and southwest, with slightly above departures from long-term averages.
2.4 SOCIO-ECONOMIC IMPACTS2.4.1 AgricultureAs rainfall is still much in the southernmost region, agricultural activities was restricted to the region, with early planting. Agriculture is the northern parts are expected to come on stream later as the rains advance.
2.4.2 HealthThe emerging high temperatures would impact negatively on the health of humans and animals particularly the poultry industry.
2.4.3 EnvironmentA drier-than-normal environment is the hallmark of this time.
2.4.4 Water Resources
12
Water stress is common during this period, including a strong challenge in the hydro-electric sector as the level of water inflow into the dams dwindle further due to high evaporation
3.0 MARCH 2014
3.1 Synoptic FeaturesThe zone which defines the meeting point between the dry North-East (NE) trade winds from the Sahara desert and the moist South-West (SW) trade winds from the Atlantic ocean commonly called Inter tropical discontinuity (ITD) continued its northward movement from a position of Latitude 9.0oN in the 3rd dekad of February to latitude 9.3oN in the 1st dekad of March. It moved further northward to latitude 10.4oN during the 2nd dekad and reached latitude 12.8oN in the 3rd dekad of the month. The ITD therefore fluctuated between latitudes 9.3°N and 12.8°N which gave a mean latitudinal position of 10.8°N for the month. The dekadal movements and average position of the ITD were all above normal during the 1st, 2nd and 3rd dekads of the month (Fig.17).
Fig 17: ITD Position in March 2014
The mean sea level pressure values over the country ranged between 1003hPa – 1014hPa in the month. The mean centre value of the St. Helena high pressure system was 1026.0hPa in the month. Daily values fluctuated between 1020.0hPa - 1034hPa. At the 850hPa level (1500m above the ground), a total of 10 vortices traversed the country. Their developments
13
Fig 17: ITD Position in March 2014
were partly responsible for the unusual rainfall experienced in some parts of the country during the period.
3.2: Temperatures
3.2.1: Maximum TemperaturesThe month recorded maximum temperatures which generally ranged from 30.0 – 42.0°C across the country (Fig. 18). The lowest values in the range of 30.0 – 34.0°C were observed over Jos, Owerri, Ado Ekiti, Iseyin, Ibadan, Oshogbo and the coastal areas. Temperatures were highest over the Northeast and Northwest where values varied between 38.0 to 43.5°C. The rest of the country recorded values in the range of 34.0 – 38.0°C
Fig18: March 2014 Maximum Temperature Fig19: March 2014 Maximum Temperature Departure
from 1981-2010 NormalMaximum temperatures in the month showed unprecedented warmer than normal conditions over the north with departures reaching as high as5.0DegC in some places such as Maiduguri, Sokoto, Nguru, Potiskum, Katsina, and Gusau. Unusually peak temperature values in excess of 40DegC were observed for several days in the extreme north. For example, Yola
recorded 20days with maximum temperatures in excess of 40DegC during March 2014. Others were Sokoto 16days, Yelwa 15days, Nguru 14days, Gusau 13days and Potiskum 11days. The significance of this is that a “heat island” was created in these areas during those long periods, reducing the comfort level of the inhabitants considerably. Temperature departures from long-term averages reached 3DegC in these area during the month. Most of the Southern cities experienced 0.5 – 1.5°C colder than normal maximum temperatures shown in blue colour. Iseyin and environs however experienced 1.9°C colder than normal conditions. (Fig.19).
3.2.2: Minimum Temperatures
14
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Abj
AkuAsaAwk
Bau
Bid
Ben
Cal
Enu
Gom
G us
Iba
Ibi
Ikj
Iko
Ije
Ilo
Ise
Jos
Kad
Kan
Kat
Laf
Lok
M ai
M ak
M in
Ngu
O goO nd
Osh
Ow e
Phc
Pot
Sok
Sha
UyoW ar
Yel
Yol
Zar
Ado
Eke
30.0
34.0
38.0
42.0
Legend
N
Latit
ude
(N)
Longitude (E)2 4 6 8 10 12 14
4
6
8
10
12
14
AB
AB
AK
BA
BE
BI
CA
EN
G O
G U
IB
EB
IJIK
IK
IL
IS
JO
KA
KN
KT
LA
LO
M A
M K
M N
NG
O GO N
O S
O W
PH
PO
SH
SO
UYW A
YE
YO
ZA
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
Trend of m axim um tem perature in March
Hotter-than-norm al in m any parts of the country in March
Minimum temperatures in the month generally ranged from 17.0 – 27.0 oC (Fig. 20). The highest range of values between 23.0 – 27.0°C were recorded over a greater portion of the country ( sky blue colour) while the lowest range of values between 17.0 – 20.0°C were recorded over Kano, Zaria and environs. Enugu, Ado-Ekiti, Calabar and other northern cities recorded minimum temperatures in the range of 20.0 - 23.0 °C (figure 20).
Fig20: March 2014 Minimum Temperature Fig21: Departures from long-term averages
Minimum temperatures compared with long term averages showed 0.5 – 6.5°C colder than normal conditions over most parts of the country. Normal conditions were observed in the coastal or southernmost areas (figure 21).
3.2.3Mean TemperaturesMean temperatures in the month showed normal conditions in most places shown in white (figure 22). Warmer than normal conditions were observed in Katsina, Gusau, Shaki and increasing over the Northeast. Cities such as Kano, Iseyin, Ibadan, Abuja, Lokoja, Makurdi, Enugu, Benin, Port Harcourt, Uyo and Calabar however observed 0.5 – 1.9°C colder than normal mean temperature conditions during the month. FIG22: DEPARTURES OF THE MEAN TEMPERATURE FROM
LONG-TERM AVERAGES
15
2 4 6 8 10 12 142
4
6
8
10
12
14
Abe
Ab j
AkuAsaAw k
B au
B id
Ben
Cal
Enu
G om
G us
Iba
Ibi
Ikj
Iko
Ije
Ilo
Ise
Jos
Kad
Kan
Ka t
Laf
Lok
Ma i
M ak
M in
Ngu
O goO nd
O sh
O w e
P hc
P ot
Sok
Sha
UyoW ar
Ye l
Yol
Za r
-3 .0
-1 .5
-0 .5
0.5
1.5
3.0
Latit
ude
(N)
Longitude (E )
N
Legend
Nor
mal
War
mer
than
Nor
mal
Col
der
than
Nor
mal
2 4 6 8 10 12 142
4
6
8
10
12
14
A be
A bj
A kuA saA wk
B au
B id
B en
Cal
E nu
G om
G us
Iba
Ibi
Ikj
Iko
Ije
Ilo
Ise
Jos
K ad
K an
K at
La f
Lok
Ma i
M ak
M in
Ngu
O goO nd
O sh
O w e
P hc
P ot
S ok
S ha
UyoW ar
Y el
Y ol
Zar
A do
E ke
17 .0
20 .0
23 .0
27 .0
Legend
Latit
ude
(N)
Longitude (E)
N
2 4 6 8 10 12 14
4
6
8
10
12
14
AB
A B
A KAO
AS
B A
B D BE
B I
C B
E B
E K
E N
G U
IB
IJIK
IK
IL
IS
IS
JA
JO
K A
K N
KT
LA
LO
M A
M I
M K
N G
O GO N
O S
O T
O W
PH
PT
SH
SO
U YW R
YE
Y L
ZA
-8.5-8-7.5-7-6.5-6-5.5-5-4.5-4-3.5-3-2.5-2-1.5-1-0.500.5
Colder-than-norm al nights in all inland areas
March 2014 m inimum tem perature departures
3.3: RAINFALLRainfall amount recorded in the month ranged from 0.0 – 380.0mm in the month (Fig.23). Places around Abuja extending southwards to the inland areas of the southeast and to areas around Awka, Ilorin and Shaki recorded rainfall in the range of 10.0 -100 .0mm while southern cities in the Niger Delta region and most of the southwest recorded 100.0 – 200.0mm of rainfall in the month. The highest rainfall of 371.2mm was however recorded over Calabar.
Fig23: March 2014 Rainfall Fig24: Departures of March rainfall from long-term means
Rainfall in March compared with 1981-2010 average values showed the highest positive departures of 204.5mm in Calabar and the lowest negative departure of 1.3mm in Asaba (Table 3). The southern parts of the country experienced predominantly wetter than normal rainfall (Fig.24), and some of the rain-events were accompanied with strong winds as was the case of 15 th
March 2014 in which there was destruction of property in the areas as shown in the satellite imageries and picture below
16
2 4 6 8 10 12 14
4
6
8
10
12
14
A B
A B
AKA O
A S
B A
B E
BI
CB
E B
EK
E N
G U
IB
IJIK
IK
IL
IS
IS
JO
KA
K N
K T
LA
LO
M A
M I
M K
NG
O GO N
O S
O W
P H
P T
S H
S O
U YW R
YE
Y L
ZA
AE
A W
DU
0
50
100
150
200
250
300
March Rainfall Trend
Rainfall am ount in m m
Figs.25a & 25b: Satellite Imagery of the rainstorm of 15th
March 2014 which caused extensive destructions of infrastructure in Anambra and Ekiti States.
Figs.25b: Newly constructed oil and gas filling station at Ukwuani, Delta
. The month’s rainfall was observed to be an improvement over the previous month in the Southeast, Southwest and around Abuja. It was also observed to be higher than 2012, 2013 and the long-term averages over Abuja, and some places in the South (Fig.26). The total rainfall recorded in the month when compared with the last two years and 1981 – 2010 normal shows that the amount of rainfall recorded in March 2014 was higher than 2012, 2013 and the long term average amount over Abeokuta, Abuja, Benin, Calabar, Enugu, Ijebu-ode, Iseyin, Ogoja and Port Harcourt.
A table containing information on rainfall amount, departure from long term average and rain days for selected stations is represented below.
Table. 3: A table containing information on some cases of heavy rainfall March.City Rainfall
(mm) Long term mean rainfall(mm)
Rainfall Departure from Long term mean(mm)
Rain days
Abuja 066.9 021.6 045.3 06Makurdi 025.6 013.9 011.7 03Enugu 120.3 052.3 068.0 09Owerri 099.7 103.2 -03.5 09Ogoja 098.7 033.0 065.7 05Oshogbo 128.1 070.7 057.4 05Akure 166.9 088.6 078.3 06Abeokuta 087.3 064.4 022.9 09
17
Fig.26: Comparison of March 2014 with 2012, 2013 and 1981-2010 Mean
Abe
Abj
Aku
Bau
Bid
Ben
Cal
Enu
Gom
Gus
Iba Ibi
Ikj
Ije Ilo Ise Jos
Kad
Kan
Kat
Lok
Mai
Mak
Min
Ngu
Ogo
Ond Osh
Ow
ePh
cPo
tSo
kUy
oW
ar Yel
Yol
Zar
050
100150200250300350400
Mar 2014RR Mar 2013RR Mar 2012RR Mar 81_10 RR
Total rainfall in March 2014, 2013, 2012 and Normal over Nigeria
Figs.25b: Newly constructed oil and gas filling station at Ukwuani, Delta
Ikeja Lagos 076.9 067.9 009.0 07Calabar 371.2 166.7 204.5 15Warri 144.4 128.0 016.4 16
Table 3 shows significant positive rainfall departures or wetter than normal conditions over Abuja, Enugu, Ogoja, Oshogbo, Akure, Abeokuta, and Calabar. Generally, rain days increased in March compared to the previous month and were highest (16 and 15 days respectively) over coastal cities such as Calabar and Warri.
3.4 SOCIO-ECONOMIC IMPACTS3.4.1 AgricultureRainfall amount continued to increase in the South and also advance northwards reaching more areas in the middle of the country, thus opening up agricultural activities in more areas. It’s a planting season and rainfall trend is seen as being adequate to support early planting activities in the South.
3.4.2 HealthHigh temperatures persisting for several days in many parts of the north created the condition for increased heat-related ailments in these States. Reports published by the Federal Ministry of Health showed high incidents of these health hazards in March.
3.4.3 EnvironmentA drier-than-normal condition following high temperatures and increased evaporation effects in the northern areas created water stress for animal breeding, and this has impacted negatively in the sector during the month. The arrival of the rains in the coming months will assist the situation positively.
3.4.4 Water ManagementThere are prospects of water availability for most uses as the rains reach the inland areas in the coming months.
The month witnessed rainfall activities across the country. This had some impacts on different cities shown in Table 2. Other impacts on Marine, Agriculture and Hydrology sub-sectors are also discussed below.
3.5 ENSO UPDATE
18
Fig. 27: ENSO-neutral is expected to continue through the Northern Hemisphere spring 2014, with about a 50% chance of El Niño developing during the summer
The model predictions of ENSO for this summer and beyond are relatively unchanged from the previous month. Almost all the models indicate that ENSO-neutral (Niño-3.4 index between -0.5°C and 0.5°C) will persist through the rest of the Northern Hemisphere spring 2014. This is in consonance with the provisions in the 2014 SRP on this subject.
3.6 SUMMARY AND CONCLUSIONThe upward movement of the major synoptic features continued slowly during January – March 2014. The ITD reached 12.8oN in during the last decade of March 2014. The maximum temperature continued its rise, reaching the peak of 43.5°C in parts of the far north in March. There was persistence of very temperature values (in the range 40.0 43.5°C) for several days in the far north, thereby creating “heat island” with extended discomfort for days. The nights were cooler in and around Kano and the southeast, it was however very warm in the southwest and parts of the northeast and northwest in January and February.
Rainfall is increasing gradually as expected, and wetter-than-normal conditions have been observed in the southwest and parts of Akwa Ibom and Cross River States, and other areas in the Niger Delta. It is expected to further move inland in the coming months.
The amount of rainfall recorded in March 2014 was observed to be higher than 2012, 2013 and the 1981 - 2010 mean values over Abeokuta, Abuja, Benin, Calabar, Enugu, Ijebu-ode, Iseyin, Ogoja and Port Harcourt. These areas will be closely watched in the coming months. The start of the 2014 rainy season brought along with it rainstorm with destructive consequences over some places in the Southeast and Southwest.
19
20