Water Cycle in Bangladesh and Prospected Activities for GEOSS in the Meghna Basin Md. Nazrul Islam Department of Physics Bangladesh University of Engineering & Technology and Shah Mohammad Iqbal Ministry of Defense Govt. of the People s Republic of Bangladesh
The water cycle or the hydrologic cycle source: website
GeoFea 30N TIBETAN PLATEAU 20N 10N INDIA MYANMAR BAY OF BENGAL EQ 60E 70E 80E 90E 100E
Fig1 Historical Rainfall records in Bangladesh Pre-monsoon MAM - 3 months Rainfall (mm) 600 500 400 300 200 1950-1999 Pre-monsoon Monsoon JJAS - 4 months Monsoon Post-monsoon ON - 2 months 100 0 JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Post-monsoon Fig. Annual rainfall in Bangladesh in different months. Data averaged for 31 stations from 1950-1999.
Bangladesh drains the combined catchment areas of the Ganges, Brahmaputra, and Meghna rivers an area equivalent to 1.75 million square kilometers. BUET
Rivers: Total=230, Major=3, 57 are transboundary rivers coming from India ~93% of the catchment areas of the rivers are located outside the country BUET
26.08 intro BRAHMAPUTRA Rain-gauge Rainfall (1950-1999) 11 10.5 10 LATITUDE (N) 25.08 24.08 23.08 22.08 GANGES 21.08 87.44 88.44 89.44 90.44 91.44 92.44 LONGITUDE (E) MEGHNA BAY OF BENGAL 9.5 9 8.5 8 7.5 7 6.5 6 5.5 5 4.5 4 mm/day Historical (1950-1999) rainfall over the country. The triangles represent the rain-gauge locations in Bangladesh.
BUET
1950 1952 1954 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 Flood 800 600 400 200 0-200 -400-600 -800 Year About 22 % of the area of the country is flooded each year Annual rainfall anomally (mm)
AnlysisArea NEPAL BHUTAN BANGLADESH INDIA Coverage of Dhaka Radar INDIA MYANMAR BAY OF BENGAL
AMJJA 2000 RAD Fig. 11. Same as Fig. 7 except averaged for 16 April to 30 August 2000.
TRMM NEPAL GANGES BRAHMAPUTRA INDIA INDIA MEGHNA BAY OF BENGAL INDIA MYANMAR TRMM 3B42 data shows the signature of high precipitation in the NE and S sides of the country. This result is consistent with radar analysis.
MIKE11-GIS WARNING! FFWC is in a development stage of Bangladesh and Dhaka inundation maps. The presented maps may in some regions be inaccurate. Inundation maps are created by combined use of a digital elevation model (DEM) of the considered area and simulated water levels by the Super Model. Especially the used DEM s for Bangladesh and Dhaka, respectively, are not precise, which may create
Evaluation of Forecast of 1998 The recent flood of 1998 has been of unprecedented magnitude and duration causing colossal damages to life, crops, properties and infrastructures of Bangladesh. During the flood 98 the Flood Forecasting & Warning Centre of BWDB issued the forecast using the MIKE-11 and Flood watch Model Systems. Flood July 2004
Prospected activities Rain-gauge data- existed and newly installed Radar data- continuous observation Upper-air observational data- as available Satellite data- if available Composite Map for real time Flood monitoring Surface Water Model- for lead time Forecasting
Facilities available and Proposed
4 3 2 2.18 3.11 Flood Areas (%) 1 0-1 -2 0.45 0.02 1954-1960 1961-1970 1971-1980 1981-1990 1991-2000 1954-2000 -1.02-3 -4-3.93 Decal Variation of Flood Areas in Bangladesh(%)
OBSERVATORIES OF BMD LOCATION OF FIRST CLASS OBSERVATORY 26 Dinajpur Rangpur Proposed FIRST CLASS OBSERVATORY 25 Bogra INDIA Mymensingh Sylhet LOCATION OF PBO Rajshahi Ishurdi Tangail Srimangal 24 Chuadanga Faridpur Dhaka Comilla INDIA LOCATION OF RAWINSONDE OBSERVATORIES 23 22 INDIA Jessore Satkhira Khulna Madaripur Barisal Bhola Patuakhali Khepupara M.Court Feni Sandwip Rangamati Hatiya Chittagong BAY OF BENGAL Coxs_Bazar 21 Teknaf 89 90 91 92
NEPAL RANGPUR BHUTAN INDIA Proposed Doppler Radar DHAKA INDIA KHEPUPARA BANGLADESH MYANMAR COX S BAZAR BMD Radar Facilities BAY OF BENGAL
JICA Rain-gauges Proposed Rain-gauges Other Rain-gauges
Requirements for MAHASRI Project in Bangladesh Renovate old JICA Rain-gauges New Rain-gauges in Meghna Basin Support for continuous radar operation Support for upper-air observation facilities (if possible) Satellite data access (if possible) Upgradation of existing Satellite data reception system
Thank You