PAKISTAN. WINTER RAINFALL PREDICTION Hazrat Mir. Cief Met Pakistan Meteorological Department 14 th, October2015

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1 PAKISTAN WINTER RAINFALL PREDICTION Hazrat Mir Cief Met Pakistan Meteorological Department 14 th, October2015

2 Monsoon 2013 seasonal forecast, PMD, Islamabad, 7 June,

3 Monsoon 2013 seasonal forecast, PMD, Islamabad, 7 June,

4 PMD: Pakistan Meteorological Department Specialized Early Warning Centers of PMD National Weather Forecasting Centre Islamabad (NWFC) Marine Meteorology & Tropical Cyclone Early Warning Centre Karachi (TCWC) National Drought Monitoring Centre Islamabad (NDMC) National Seismic Monitoring & Tsunami Early Warning Centre Karachi (NTWC) Flood Forecasting Division Lahore (FFD) Flood Forecasting & Warning Centre For Lai Nullah Basin Islamabad

5 Winter Rainfall In the winter season rainfall in Pakistan is caused by Sub-tropical low pressure systems that originate in the Mediterranean Sea, called the Western Disturbances. The country s biggest river Indus is fed by this accumulated snow which plays the major role for agriculture, water reservoirs, glacier basins, power generation, wild-life and ecosystems. Winter precipitation is of tremendous importance from the point of view of water reservoirs which are crucial for country s agriculture and power generation 5

6 Spatial Distribution of Winter Rainfall Higher rainfall over northern parts. Rainfall intensity decreases towards extreme northern and southern parts. 6

7 Monthly Spatial Distribution of Winter Rainfall JANUARY FEBRUARY MARCH 7

8 Monthly Rainfall Variation January to March rainfall are almost similar and contribute 6% to 10% of annual rainfall. 8

9 Seasons Contribution of Rainfall The contribution of winter (January- March) rainfall is 25 % of annual rain. 9

10 The Predicting Regression Equation 10

11 Geographical Locations of the Predictors used in Model 11

12 Details of Predictors SN Predictor Region/Station Period 1 South American Pressure 2 South American Pressure Mean Station Level pressure Mean Station Level pressure 3 Western rainfall Buenos Aires Cordoba Santiago Buenos Aires Cordoba Santiago Tehran Isphahan Mashad Baghdad November November November December December December December December December December 12

13 The calculated percentage departure of the expected rainfall in Pakistan from the normal rainfall is classified as follows: Sr. No. Predefined classification of Rainfall Percentage departure of forecast rainfall from normal Classification used for describing the rainfall forecast 1 Above 50 % Largely above normal 2 26 % to 50 % Moderately above normal 3 11 % to 25 % Slightly above normal 4-10 % to +10 % Normal 5-11 % to -25 % Slightly below normal 6-26 % to -50 % Moderately below normal 7 Below -50 % Largely below normal 13

14 PMD Seasonal Climate Outlook (Oct - Dec) 2015

15 Seasonal Prediction Approach Goal of Seasonal Prediction is to reduce the adverse socio-economic consequences of climate variability and change. The current scientific approach Lower-boundary forcing, which gives rise to atmospheric perturbations, evolves more slowly than the atmospheric perturbations themselves and that the response of the atmosphere to this forcing is detectable. All the seasonal prediction systems are working on this principal 10/20/

16 Seasonal Prediction Method Observed large scale climate Transfer function (Dynamical/statistical model) Predicted large scale climate Observed small scale climate Predicted small scale climate 10/20/

17 Observed Area-weighted Rainfall Anomaly for Winter (JFM) Over Pakistan No significant relation with El Niño Source: Pakistan Meteorological Department 10/20/

18 Seasonal (Octo-Dec) climate out look prediction provides information that how the weather condition is expected as compared to the normal atmospheric conditions. Output of the Combined General Circulation Model (CGCM) is downscaled to obtain the seasonal forecast. Normal to above normal ( ) precipitation is expected in most parts of the country during the season October-December

19 Seasonal (Octo-Dec) climate out look Con) Khyber Pakhtoonkhwa, Azad Jammu and Kashmir, Punjab and Baluchistan are expected to get above normal precipitation with maximum bias in stations like Muree, Muzafarabad, Saidu Sharif and the adjoining areas. While southern parts of Sindh province are expected to get slightly below normal rainfall durind the season 19

20 20

21 Monsoon 2013 seasonal forecast, PMD, Islamabad, 7 June,

22 Seasonal Climate Outlook /20/

23 Monthly Climate Outlook /20/

24 Monthly Climate Outlook /20/

25 Monthly Climate Outlook /20/

26 % Accuracy Level Accuracy Level for Seasonal Forecast by PMD /20/

27 Significant Trend of annual Precipitation(mm) across Pakistan ( ) Maximum Increase in Precipitation at Mianwali = 6.18 mm/year Maximum decrease in Precipitation at Ghari Dupatta = 9.15 mm/year

Maximum Increase in Max. Temp. at Dalbandin = 0.

28 SIGNIFICANT TREND OF MEAN MONTHLY MAXIMUM TEMPERATURE ( C) ACROSS PAKISTAN( ) Maximum Increase in Max. Temp. at Dalbandin = C/year Maximum decrease in Max. Temp. at Cherat = C/year

29 Monsoon 2013 seasonal forecast, PMD, Islamabad, 7 June,

30 Monsoon 2013 seasonal forecast, PMD, Islamabad, 7 June,

31 THANK YOU 31

Seasonal Forecasting at Pakistan Meteorological Department

Seasonal Forecasting at Pakistan Meteorological Department by Zubair Ahmed Siddiqui Director R.M.C. Gilgit-Baltistan, Pakistan Meteorological Department siddiqui@pmd.gov.pk Area : 796,095 km2 Population: