Reducing vulnerability to water-related disasters
Several scientific findings have quantified that the stream flows of the three mighty rivers in Bangladesh are highly correlated to the rainfall in the upper catchments in India with typically a lag of about one to three months. These findings are not elaborately described here; these are reported elsewhere [Chowdhury and Ward (2004): Hydro-Meteorological Variability in the Greater Ganges-Brahmaputra-Meghna (GBM) Basins, International Journal of Climatology]. Therefore, stream-flows in Bangladesh could be fairly estimated for one to three months in advance -- especially for the Ganges and Brahmaputra Rivers -- by employing simple correlation, if rainfall data from further upper catchments in India are available on a real time and continuous basis. Therefore, hydro-meteorological information exchange between the courtiers along the Indo-Gangetic basins is essential for developing a knowledge base for evaluating the potential implications of water resources management in the greater Ganges-Brahmaputra-Meghna (GBM) basins in South Asia.
At present, unfortunately, with reference to the sharing of information among the riparian countries, the water experts in one country had surprisingly little access to information from the other co-basin countries. Thus, some operational mechanism is needed for wider sharing of meteorological and hydrological information between the countries concerned. The SAARC can play a proactive role to foster a closer regional cooperation by enhancing the capability of exchanging water-related information to reduce the sufferings of humanity in three river basin areas.
For all latest news, follow The Daily Star's Google News channel. Next, some of the recent findings have clearly demonstrated about the greater potential for developing seasonal climate forecasting scheme in the Indo-Gangetic basin areas (for details, see the above reference paper, and also other references listed therein). Despite some problems of regular exchange of data among the neighbouring countries, the process of seasonal climate forecasts (rainfall, stream-flow, and flooding) can still be enhanced from the unusually warm or cold sea surface temperatures (SSTs) in the tropics. For example, unusually warm or cold sea surface temperatures in the tropical Pacific or Indian Ocean can cause major shifts in seasonal climate in nearby continents like India, Bangladesh, Nepal, and Sri Lanka. Therefore, the advance knowledge on El Nino/Southern Oscillation (ENSO) condition (SST and atmospheric circulation pattern) ahead of time would provide substantial opportunities to provide useful climate forecast (rainfall, stream-flow, flooding) in the greater GBM basin areas in South Asia. This is a very complicated and challenging task, which is extremely difficult without a full scale regional co-operation.
Although in India considerable work has been done on variability of climate and particularly rainfall by analysis of the extensive data sets of the Indian Meteorological Department (IMD), the nature of climate variability over other parts of the Indian monsoon regime, such as Bangladesh, Sri Lanka, Nepal, and Pakistan, is not as well documented. Therefore, considerable work on the nature of climate variability and predictability of these countries are required to be done before developing any full scale regional forecasting schemes. This detailed investigation on the relationship between the Bangladeshi monsoon and monsoons of the countries in South Asia, in particular India, will also enhance our understanding of the large-scale features of the monsoon in the greater Ganges-Brahmaputra-Meghna (GBM) basin system.
Like many other SAARC countries, Bangladesh at present is not in a position to identify the uncertain impacts of an ENSO and other climate factors. The country, therefore, has to rely on the latest ideas and technology from developed countries for this purpose. Other SAARC countries, like India, can also make a significant contribution here with their knowledge and expertise. The SAARC can also take a proactive role to foster a closer regional cooperation and reduce the sufferings of humanity in three river basin areas.