1. The weather and climate of Malaysia
Ahmad Fairudz Jamaluddin
Malaysian Meteorological Department
Ministry of Science, Technology and Innovation

2. Outline General Climate of Malaysia Climate Long Term Mean of Malaysia
Observed Trend of Climate Extremes in Malaysia
How Regional Climate Model can enhance MMD’s services
Seasonal / Monthly Weather Outlook
Drought Monitoring
Fire Danger Rating
Summary

3. GENERAL CLIMATE OF MALAYSIA
Tropical maritime climate with:
- uniform temperature
- high humidity
- rainfall throughout the year
The seasons:-
- Northeast Monsoon (Nov – Mar)
- Southwest Monsoon (June – August)
- Two Inter-Monsoon (Apr-May & Sept-Oct)

4. Flood Flash Flood Haze Severe Weather in Malaysia
Inter-Monsoon (Apr-May & Sep-Oct)
Northeast Monsoon (Nov – Mac)
Flood
Flash Flood
Southwest Monsoon (Jun – Aug)
Haze
Strong Wind and Rough Sea

5. Monsoon & Dominant Modes of Climate Variability
SWM (Late May to Sept)
NEM (Nov to March)
PACIFC OCEAN
MJO
ENSO
INDIAN OCEAN
IOD
Indian Ocean Dipole (IOD), El Nino-Southern Oscillation (ENSO) ---- Interannual oscillation (2-7 years)
Madden-Julian Oscillation (MJO) – intra-seasonal oscillation (20-60 days)

6. Climate Long Term Mean in Malaysia

7. Monthly Rainfall Over PM
Long Term Mean
Monthly Rainfall Over PM
Northeast Monsoon
JANUARY
DECEMBER
NOVEMBER
> 500
Southwest Monsoon
JUNE
JULY
AUGUST

8. Mean Monthly Average Temperature Over PM
Northeast
Monsoon
Southwest
Monsoon

9. Mean Monthly Average RH Over PM
NOVEMBER
DECEMBER
JANUARY
Northeast
Monsoon
JULY
AUGUST
SEPTEMBER
Southwest
Monsoon

10. Monthly Rainfall Over EM
Long Term Mean
Monthly Rainfall Over EM
DECEMBER
JANUARY
FEBRUARY
Northeast Monsoon
0 – 50
50 – 100
100 – 150
150 – 200
200 – 250
250 – 300
300 – 400
400 – 500
> 500
Southwest Monsoon
JULY
AUGUST
JUNE

11. Mean Monthly Average Temperature
Over EM
Northeast Monsoon
Southwest Monsoon

12. Observed Trends of Climate Extremes in Malaysia

13. CONVECTIVE TIME SCALE Trends in 2 hour maximum rainfall
Frequency of Heavy Rainfall (blue) (>20mm) & Intensity (red) for 2 Hour Maximum Rainfall. Number in box indicates trends in PRCPTOT.
(Diong et al.; MMD)

14. SEASONAL TIME SCALE Trends in heavy rainfall
Frequency of Heavy Rainfall (blue) (>20mm)
& Intensity (red) during Southwest Monsoon (JJA).
Number in box indicates trends in PRCPTOT.
(Diong et al.; MMD)

15. SEASONAL TIME SCALE Trends in heavy rainfall
Frequency of Heavy Rainfall (blue) (>20mm)
& Intensity (red) during Northeast Monsoon (DJF).
Number in box indicates trends in PRCPTOT.
(Diong et al.; MMD)

16. ANNUAL TIME SCALE Trends in heavy rainfall
Frequency of Heavy Rainfall (blue) (>20mm) & Intensity (red) for annual rainfall. Number in box indicates trends in PRCPTOT.
(Diong et al.; MMD)

17. In general the intensity and frequency of extreme rainfall events are on the rise.
The SW monsoon season is becoming wetter but at the same time prolonged dry spells are more frequent.
During the NE monsoon season the extreme rainfall events associated with the monsoon surges and other synoptic features are on the rise.
Notable increasing trend in the annual precipitation is observed in EM with both the monsoon seasons possibly contributing to this trend.

18. How Regional Climate Model can enhance MMD’s services

19. Seasonal / Monthly
Weather Outlook

20. Moisture convergence (mm/day) Moisture flux during JJA (1979-2000)
Climate Variability
Moisture convergence (mm/day)
Moisture flux during JJA ( )
Tangang et. al. (2007)
Indian Ocean experience warming SST relatively faster than other oceans including Pacific Ocean
Indian Ocean as source of moisture for PM during JJA. South China Sea / Pacific Ocean as source of moisture for Malaysian region during DJF
How this SST warming over Indian and Pacific Ocean modulate/change rainfall distribution and extreme weather event over the Malaysian region?

21. Indian Ocean Dipole (IOD)
Composite Anomalous OLR, Mode -ve IOD years, Mode +ve IOD years during JJA
Anomalous OLR (W/m2)
During Mode –ve IOD, Malaysian region experience neutral condition compare to wetter condition over the South of Sumatra during JJA
During Mode +ve IOD, Malaysian region experience dry condition over the south of PM and Sarawak during JJA. However, south of Sumatra and Borneo experience driest condition during the period.

22. El-Nino Southern Oscillation Index (ENSO)
Composite Anomalous OLR &
La-Nina years during JJA
Anomalous OLR (W/m2)
El-Nino years during JJA
Wet condition over south of PM and Sarawak during La-Nina. Dry condition over south of PM, Sarawak and south of Sabah during El-Nino (JJA)

23. Conventional ENSO vs ENSO-Modoki
Composites of Anomalous DJF Precipitation
Conventional El Nino
El Nino Modoki
Composites of Anomalous DJF Precipitation, Anomalous wind at 850hPa
(Ester Salimun, UKM)

24. Composites of MJO Phases, Anomalous Precipitation & wind at 925hPa during JJA
(Fairudz et. al., MMD)

25. Diurnal Rainfall and MJO during JJA
Phase 1 + 2
Phase 3 + 4
Phase 5 + 6
Phase 7 + 8
Afternoon
(15 – 20 MST)
Evening
(21 – 02 MST)
Composites of MJO Phases, standardized anomalous precipitation during afternoon and evening over PM
(Fairudz et. al., MMD)

26. LOCAL ATMOSPERIC CIRCULATION
CIN (J/kg) at 20 MST
Phase 1 + 2
Afternoon (15 – 20 MST)
Stesen
Phase 1+2
Phase 3+4
Phase 5+6
Bayan Lepas
75.12
91.56
86.12
KLIA
75.83
59.51
106.5 H
CAPE (J/kg) at 20 MST
Stesen
Phase 1+2
Phase 3+4
Phase 5+6
Kuantan
1972.3
2784.1
2523.6
Relatively low CIN over the west cost of PM during phase 1+2 MJO. Relatively high CAPE over east coast of PM during phase 3+4 MJO.
Now we turning to the composite of the MJO and surface circulation during the afternoon
period. In upper panel, we see that the sea breeze respond differently to the propagation
of MJO. During earlier phases of MJO, the MJO played the main role in allowing the
moisture to come into the region. The moisture mostly come from the South China Sea
and Indian Ocean. On the other hand, narrow straits of Malacca brings relatively drier air
to the region. In lower panel, we see the divergence mostly concentrate over the coastal area.
This is due to the interaction of local sea breeze and dominant monsoon wind.
To understanding better about the impacts of the MJO, the convective indices were analyze.
In upper table, generally peninsular Malaysia experiences relatively weaker CIN in earlier phases
of the MJO. As example KLIA, weaker CIN can be observed in earlier phases compared to later,
and this is associated with relatively wetter conditions during afternoon period over the region.
In lower panel, higher CAPE were observed during the wet phases of the MJO. As example over
the Kuantan region, highest CAPE with J/kg observed, these associated with the wetter
conditions during late evening period over the region. L
Left panel: Composite of MJO’s phase, anomalous mslp (contour), anomalous RH (value) and direction of surface wind (vector). Right panel: Composite of MJO’s phase, anomalous surface divergence, anomalous surface temperature.

27. Composites of MJO Phases, Anomalous Precipitation & wind at 925hPa during DJF

28. STATISTICAL DOWNSCALING Probabilistic forecast
Statistical downscaling from JMA CGCM (three month lead time and 51 members)
Method of “double leave one-out cross-validation” with multiple size of optimal window is used to validate the model at each meteorological station. The highest correlation coefficient with station's precipitation was selected as predictor.
SON 2011
Probabilistic forecast
for SON 2011
(Yip et. al., MMD)

29. GCM’S SEASONAL PRODUCTS
NDJ
NDJ
ECMWF
JAMSTEC

30. Rainfall Outlook for November 2012

31. Meteorology Drought Monitoring

32. Meteorology Drought Event in Malaysia
based on SPI Index
Category
Number of Events
Percentage
Drought Event 14
46.6%
No Drought Event 16
53.3%
Event
Number of Events
Percentage
El-Nino 10
71.4%
La-Nina 2
14.2%
Others
Year
(Fatin Nurashikin, UKM)
Latest 3-month SPI Index less than -1.0

33. Meteorology Drought Monitoring
& Latest 3-month SPI less than -1.5
LEVEL
CONDITIONS
WARNING
Latest 3-month and 6-monthly cumulative rainfall amount exceed 35% deficit from normal with latest 3-month SPI Indexs less than and the previous drought level was catogorized as ALERT.
DANGER
Latest 3-month and 6-monthly cumulative rainfall amount exceed 35% deficit from normal with latest 3-month SPI Indexs less than – 2.0 and the previous drought level was catogorized as WARNING.
Defisit jumlah hujan kumulatif 3 bulan dan 6 bulan semasa melebihi 35% dari normal dan indeks SPI 3 bulan terkini kurang dari -1.5 serta tahap kemarau sebelumnya telah pun dikategorikan WASPADA.
Defisit jumlah hujan kumulatif 3 bulan dan 6 bulan semasa melebihi 35% dari normal dan indeks SPI 3 bulan terkini kurang dari -2.0 serta tahap kemarau sebelumnya telahpun dikategorikan AMARAN.

34. National & ASEAN Country
Fire Danger Rating
National & ASEAN Country
(currently 3 days forecast (WRF) with 4km resolution for Malaysia &
36km for SEA region

35. Normal peatswamp (Neutral ENSO - August 2012)
Situation of sudden mortality of peatswamp trees (too much water over the area –
La-Nina 2011)

36. North Selangor PSF
Sungai Karang FR
Raja Musa FR
Selangor

37. Pandangan daripada kompartmen 89 kiri terusan
Forest fires at RMFR –
August 2012 ( 407 ha)

38. Pandangan daripada kompartmen 89

39. Forest fires at RMFR – 2012 ( 407 ha)

40. FFMC code during 18 – 29 August 201219 20 21 22 23 24 25 26 27 28 29

41. DMC code during 18 – 29 August 201219 20 21 22 23 24 25 27 28 26 29

42. Fire spreading underground (Paya Indah Wetland)

43. Fire spreading underground (Paya Indah Wetland)

44. ISI code during 1 – 10 June 2012 ISI : 1 – 10 Jun 2012 1 2 3 4 5
ISI extreme on 4 June 2012, same day burning start (rain on 9 June 2012)
ISI : 1 – 10 Jun 2012 6 7 8 9 10

45. ISI code during 21 – 30 June 2012 ISI : 21 – 30 June 2012 21 22 23 2425
ISI extreme throughout the burning period except on a few days due to rain (drastic change)
ISI : 21 – 30 June 2012 26 27 28 29 30

46. Summary
In general, the intensity and frequency of extreme rainfall events are on rise
Climate variability over the Malaysian region is strongly influence by monsoon, ENSO, IOD and MJO
Malaysian forestry and water resources are too sensitive to any changes/shifting of the climate
Reliable RCMs are crucial and important to enhance MMD’s services such as accurate seasonal/monthly weather outlook, drought monitoring and fire danger rating

47. 15/04/2017
Terima Kasih
Dr. Tam Weng Wah

48. Agriculture; Agro-Climatological
Zonation

49. Suitable not being Planted
States
State Areas (ha)
Actual Planted (A)
% Planted
Suitable (S)
% Suitable
Suitable not being Planted
Johor
1,891,510
829,036
43.8
41,761
2.2
22,578
Oil Palm Cultivation Areas for Johore
Suitability Areas (Marginal) for Oil Palm Cultivation in Johore
Oil Palm Planted on Suitability (Marginal) land in Johor
Annual Average Rainfall
Annual Average Temperatures
Soil Suitability Sub-Classes
Classification by Terrain Limits: (Class 3 or less) where; mm
24°C to 28°
Suitable : 1n, 2d and 2dt
Class 1
Class 2
Class 3
0-2°
>2-6°
>6-12°
Marginal: 2DGn, 2Gn, 2Dt(G), 2Gnt, 2cGnt, 2cd, 2cdGnt, 2dnT, 2dnt, 2nT, 2nT(G), 3D(nt), 3G, 3G(cn), 3G(cnT), 3G(n),3G(nt), 3G(t), 3R(n), 3d, 3d(n), 3d(t), 3dt, 3t(G), 4dt, 4dt(n)

50. Composites of MJO Phases, Anomalous OLR, Anomalous Geopotential Height at 500hPa & wind at 850hPa during JJA