Bangladesh Meteorological Department Research Articles

Disparities in Risks of Malaria Associated with Climatic Variability among Women, Children and Elderly in the Chittagong Hill Tracts of Bangladesh.

Malaria occurrence in the Chittagong Hill Tracts in Bangladesh varies by season and year, but this pattern is not well characterized. The role of environmental conditions on the occurrence of this vector-borne parasitic disease in the region is not fully understood. We extracted information on malaria patients recorded in the Upazila (sub-district) Health Complex patient registers of Rajasthali in Rangamati district of Bangladesh from February 2000 to November 2009. Weather data for the study area and period were obtained from the Bangladesh Meteorological Department. Non-linear and delayed effects of meteorological drivers, including temperature, relative humidity, and rainfall on the incidence of malaria, were investigated. We observed significant positive association between temperature and rainfall and malaria occurrence, revealing two peaks at 19 °C (logarithms of relative risks (logRR) = 4.3, 95% CI: 1.1–7.5) and 24.5 °C (logRR = 4.7, 95% CI: 1.8–7.6) for temperature and at 86 mm (logRR = 19.5, 95% CI: 11.7–27.3) and 284 mm (logRR = 17.6, 95% CI: 9.9–25.2) for rainfall. In sub-group analysis, women were at a much higher risk of developing malaria at increased temperatures. People over 50 years and children under 15 years were more susceptible to malaria at increased rainfall. The observed associations have policy implications. Further research is needed to expand these findings and direct resources to the vulnerable populations for malaria prevention and control in the Chittagong Hill Tracts of Bangladesh and the region with similar settings.

An Association between Rainy Days with Clinical Dengue Fever in Dhaka, Bangladesh: Findings from a Hospital Based Study.

Background: Dengue, a febrile illness, is caused by a Flavivirus transmitted by Aedes aegypti and Aedes albopictus mosquitoes. Climate influences the ecology of the vectors. We aimed to identify the influence of climatic variability on the occurrence of clinical dengue requiring hospitalization in Zone-5, a high incidence area of Dhaka City Corporation (DCC), Bangladesh. Methods and Findings: We retrospectively identified clinical dengue cases hospitalized from Zone-5 of DCC between 2005 and 2009. We extracted records of the four major catchment hospitals of the study area. The Bangladesh Meteorological Department (BMD) provided data on temperature, rainfall, and humidity of DCC for the study period. We used autoregressive integrated moving average (ARIMA) models for the number of monthly dengue hospitalizations. We also modeled all the climatic variables using Poisson regression. During our study period, dengue occurred throughout the year in Zone-5 of DCC. The median number of hospitalized dengue cases was 9 per month. Dengue incidence increased sharply from June, and reached its peak in August. One additional rainy day per month increased dengue cases in the succeeding month by 6% (RR = 1.06, 95% CI: 1.04–1.09). Conclusions: Dengue is transmitted throughout the year in Zone-5 of DCC, with seasonal variation in incidence. The number of rainy days per month is significantly associated with dengue incidence in the subsequent month. Our study suggests the initiation of campaigns in DCC for controlling dengue and other Aedes mosquito borne diseases, including Chikunguniya from the month of May each year. BMD rainfall data may be used to determine campaign timing.

Climate change and its influence on occurrence and distribution of Anthrax in Bangladesh

Background: Anthrax is a serious infectious disease of human and animals. It is caused by the gram positive spore forming bacteria Bacillus anthracis. This study assessed the interrelationship between climate change and occurrence of anthrax outbreaks in Bangladesh. Methods & Materials: Meteorological daily data from 35 meteorological observatory stations across the country were collected from Bangladesh Meteorological Department, Dhaka and anthrax outbreak data were collected from Department of Livestock Services (DLS), Bangladesh from 2010 to 2014. The data were entered into a spreadsheet program (Excel 2007, Microsoft) and transferred into STATA/SE 13.0 for data analysis. Descriptive statistical analysis, Pearson correlation and regression analysis were applied. Results: The highest monthly outbreak number was 1,100 in September 2013 and the second highest was >800 in May 2010. The average, maximum and minimum temperature were recorded as 26.02333, 30.1 and 16.8 °C; humidity were 79.82%, 87.4% and 67.9%; rainfall were 5.988333, 19.5 and 0 mm; cloud coverage were 3.47, 6.5 and 0.6 h/day and wind speed were 2.45 knot, 3.9 knot and 1.4 knot, respectively over the country. There was a significant positive correlation (p < 0.05) among the outcome series and temperature (°C), rainfall (in mm), cloud coverage (in hour) and wind speed (knot). In case of temperature (°C), predicted anthrax outbreak = −130 + 14.836X temperature. When temperature increases by 1 °C, anthrax outbreak increases by 14.836. There was a peak of outbreaks each year in the summer and rainy season, March to September. Predicted anthrax outbreak for rainfall (in mm) = 199.4629 + 9.452X rainfall; for cloud coverage (1 h/day) = 128.75 + 36.69X cloud coverage and for wind speed (knot) = −6.0879 + 107.0X wind speed. When rainfall increases by 1 mm, cloud coverage increases by 1 h/day and wind speed increases by 1knot, anthrax outbreak increases by 9.452, 36.69021 and 107.0019, respectively. Conclusion: The results of the present study showed that increasing the ambient temperature and the occurrence of heavy rainfall as well as cloud coverage and wind speed acceleration in the monsoon season significantly contribute to the anthrax outbreaks in Bangladesh.

Effect of meteorological factors on COVID-19 cases in Bangladesh.

This work is intended to examine the effects of Bangladesh's subtropical climate on coronavirus diseases 2019 (COVID-19) transmission. Secondary data for daily meteorological variables and COVID-19 cases from March 8 to May 31, 2020, were collected from the Bangladesh Meteorological Department (BMD) and Institute of Epidemiology, Disease Control and Research (IEDCR). Distributed lag nonlinear models, Pearson’s correlation coefficient and wavelet transform coherence were employed to appraise the relationship between meteorological factors and COVID-19 cases. Significant coherence between meteorological variables and COVID-19 at various time–frequency bands has been identified in this work. The results showed that the minimum (MinT) and mean temperature, wind speed (WS), relative humidity (RH) and absolute humidity (AH) had a significant positive correlation while contact transmission had no direct association with the number of COVID-19 confirmed cases. When the MinT was 18 °C, the relative risk (RR) was the highest as 1.04 (95%CI 1.01–1.06) at lag day 11. For the WS, the highest RR was 1.03 (95% CI 1.00–1.07) at lag day 0, when the WS was 21 km/h. When RH was 46%, the highest RR was 1.00 (95% CI 0.98–1.01) at lag day 14. When AH was 23 g/m3, the highest RR was 1.05 (95% CI 1.01–1.09) at lag day 14. We found a profound effect of meteorological factors on SARS-CoV-2 transmission. These results will assist policymakers to know the behavioral pattern of the SARS-CoV-2 virus against meteorological indicators and thus assist to devise an effective policy to fight against COVID-19 in Bangladesh.

Study on Sensitivity of Microphysics for the Simulation of Rainfall for the Month of May 2015 over Bangladesh using High Resolution WRF-ARW Model

In this research the Advanced Research WRF (ARW) model v3.8.1 has been used to simulate the rainfall of May 2015 all over Bangladesh. The model was configured in nested domain with 18 and 6 km horizontal grid spacing with 100 × 96 and 103 × 127 grids in the east-west and north-south directions, respectively with 30 vertical levels. The Lin et al., WSM6, Thomson, Morrison Double-Moment (M-2Mom), Stony Brook University (SBU), and WDM6 microphysics schemes coupling with Kain-Fritsch (KF) cumulus parameterization (CP) scheme have been used to simulate the monthly total rainfall, heavy rainfall, monthly rainy days and heavy rainy days for the month of May 2015 at all meteorological stations of Bangladesh. The simulated results are compared with the observed results of 33 meteorological stations of Bangladesh Meteorological Department (BMD) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) output. Relative standard deviation of all observed, PERSIANN and model simulated parameters have been analyzed and compared. The maximum monthly observed rain in May 2015 at Sylhet was 752 mm but WSM6, M-2Mom and WDM6 schemes have simulated 831, 788 and 742 mm for day 1 prediction; WSM6, WDM6 and SBU-Lin schemes have simulated 757, 916 and 981 mm for day 2 prediction and WSM6 and WDM6 schemes have simulated 741 and 925 mm for day 3 prediction, respectively and all other MPs have simulated much higher rainfall at domain (D1). The WDM6, M-2Mom and Lin et al. schemes have simulated 744, 807 and 923 mm for day 1 prediction, WSM6 and WDM6 schemes have simulated 714 and 877 mm for day 2 predictions and WSM6, SBU-Lin and Lin et al. schemes have simulated 802 and 913 and 998 mm, respectively for day 3 predictions at domain (D2). The relative standard deviation (RSD) has minimum at D1 and D2 for WDM6 scheme for day 1 prediction and WSM6 scheme for day 2 and day 3 predictions for the monthly total rainfall and heavy rainfall of May 2015. The results suggest that as the forecast time increased the amount of total rain and also heavy rain is increased. As a result RSD is also increased for all MPs. WDM6 scheme gives the better performance of rainfall and rainy days all over the country.&#x0D; Journal of Engineering Science 11(1), 2020, 43-60

On the heat waves in Bangladesh, their trends and associated large scale tropospheric conditions

Attempts have been made to study the heat waves along with the trends in Bangladesh and the large-scale tropospheric conditions over Bangladesh and neighbourhood responsible for generating heat waves in the country. Maximum temperature (Tmax) for the period 1981-2016 has been used in the study. Based on the definition of heat waves of Bangladesh Meteorological Department (BMD), the frequencies of days with Tmax≥360C and ≥ 380C have been computed and their trends are investigated to delineate the areas of heat waves in Bangladesh. During the period 1981-2016, Tmax≥360C is found to prevail annually for 79 days at Rajshahi, 51 days at Mongla, 50 days at Khulna in 2014 whereas it is found to prevail annually for 85 days at Chuadanga in 1992, 78 days at Jessore in 2010, 72 days at Satkhira in 1986 and 68 days at Ishurdi in 1995. In 2014, Tmax≥360C is found to exist annually for many days in western pat of Bangladesh in comparison to the eastern and costal region of the country. That is why year 2014 has been selected to study waves extensively. The study reveals that the monthly, seasonal and annual frequency of Tmax≥360C have increasing trends in Bangladesh except a very few places, having the highest increasing trends over southwestern part of the country with increasing rates of 0.816 day/year and 1.02 day/year, respectively at Mongla. The highest increasing trends over southwestern part may be due to the advection and penetration of higher Tmax due to northwesterly winds and less rainfall over the area. The seasonal and annual frequencies of Tmax≥380C have increasing trends at less than 50% stations in Bangladesh; some of the increasing trends of the seasonal and annual frequency of maximum temperature ≥380C are statistically significant up to 95-99% level of significance. The large-scale synoptic conditions show that heat waves are found to enter Bangladesh from the west/northwest due to the advection of higher Tmax from the west. Heat waves extend from west to east up to about central Bangladesh and a separate area of heat waves develop over the Chittagong Hill Tracts, the reason of which may be due to the diverging pattern of wind flows near the Chittagong Hill Tracts in the year of heat waves. Heat waves are absent along Sandwip-M.Court-Feni-Comilla region. In 2014, heat waves are found to be due to the influence of sub-tropical high over India and its extension over Bangladesh at the surface and at 850 hPa level with strong westerly/northwesterly winds at 850 hPa, influence of anticyclones persisting for many days over the Bay of Bengal at 300 hPa level, absence of upper level westerly troughs over India and Bangladesh&#x0D; Journal of Engineering Science 11(1), 2020, 19-36

Impacts of cyclone and flood on crop and fish production in disaster prone coastal Bhola district of Bangladesh

This study assessed the impact of climate change induced disaster on crops and fisheries production at Bhola Sadar and Monpura upazila of Bhola district, Bangladesh during January to June 2018. The study was gathered primary data from primary observation (PO), questionnaire survey (QS), focus group discussion (FGD), and key informant interview (KII). Secondary data were collected from Upazila Agricultural Office and Upazila Fisheries Office of Bhola Sadar and Manpura upazila and moreover, climatic data were collected from Bangladesh Meteorological Department. Results of the study found that trend analysis indicates overall annual maximum temperature increased for Kharif-I, Kharif-II and Rabi season. Average annual minimum temperature also increased for Kharif-I season but decreased for Kharif-II and Rabi season. Study also found that for all cropping season average relative humidity was increased. Annual average rainfall exhibited decreasing trend for Kharif-I and Rabi season but increased for Kharif-II season in (1990-2019) time period. The Aus, T. Aman, Boro and Mung bean was dominant cropping pattern in Kharif-I, Kharif- II and Rabi season in Bhola district. Overall, Aus rice production in Kharif-I season increased but in 2009, 2013 production was decreased because of cyclone Aila (2009) and Cyclone Mahasen (2013). T. Aman production hampered due to Cyclone Sidr (2007) and flood (2014) in Kharif-II season. In Rabi season Boro rice production lessen because of low rainfall and salinity intrusion. Overall, Mung bean production increase but in 2008 and 2009 production become hampered due to late cultivation because of Cyclone Sidr (2007). Fish production rate increase in Bhola specially Hilsha fish because of non-climatic factor like raid in non-fishing time, banned current net but fish production in pond become diminished due to infrequent natural disaster. Practicing of salt and flood tolerant varieties, floating bed vegetable cultivation, and mixed cropping system (mainly for Rabi season), enhanced expedition activities against catching mother Ilish in prohibition period, dredging in the heart of the river which can eventually reduce vulnerabilities and increase crop and fish production in the Bhola region.&#x0D; Int. J. Agril. Res. Innov. Tech. 10(1): 40-55, June 2020

PM&lt;sub&gt;2.5&lt;/sub&gt; concentration and meteorological characteristics in Dhaka, Bangladesh

Air quality in Dhaka city is gradually deteriorating due to increase of pollutants in air. This study aims to assess the concentration of particulate matter (PM) with an aerodynamic diameter ≤2.5 μm (PM2.5) and its relationship with meteorological parameters in highly polluted Dhaka city. Data for PM2.5 has been collected from the Air Now Department of State (AirNow DOS) and meteorological data from Bangladesh Meteorological Department (BMD). Study observed that 31.9% of hourly Air Quality Index (AQI) category was unhealthy while the percentage of ‘Good’ was very few. The maximum monthly average concentration was found to be 192.97±89.30 μg/m3 in the month of January while minimum average concentration was 29.98±19.37 μg/m3 in July. Besides, it also found that winter season had highest PM2.5concentration among all seasons. Moreover, the annual concentration was found to be 79.94±75.55 μg/m3 in 2017 which exceeded the National Ambient Air Quality Standard (NAAQS) and World Health Organization (WHO) standard. A number of meteorological factors are affecting to this variation. It is also found that rainfall is negatively strong and significantly correlated with the concentration of PM2.5, due to ambient dust are being settle down in the lithosphere. Annual concentration of PM2.5 was 5 times higher than standard level.&#x0D; Bangladesh J. Sci. Ind. Res.55(2), 89-98, 2020

Impact of climate variability on length of stay in hospital for childhood pneumonia in rural Bangladesh

ObjectivesPneumonia is a significant contributor to mortality and morbidity in children aged <5 years, and it is also one of the leading causes of hospitalisation for children in this age group. This study assessed the association between climate variability, patient characteristics (i.e. age, sex, weight, parental education, socio-economic status) and length of stay (LOS) in hospital for childhood pneumonia and its economic impact on rural Bangladesh. Study designAn ecological study design was used. MethodsData on daily hospitalisation for pneumonia in children aged <5 years (including patient characteristics) and daily climate data (temperature and relative humidity) between 1st January 2012 and 31st December 2016 were obtained from the Matlab Hospital (the International Centre for Diarrhoeal Disease Research, Bangladesh) and the Bangladesh Meteorological Department, respectively. A generalised linear model with Poisson link was used to quantify the association between climate factors, patient characteristics and LOS in hospital. ResultsThe study showed that average temperature, temperature variation and humidity variation were positively associated with the LOS in hospital for pneumonia. A 1°C rise in average temperature and temperature variation during hospital stay increased the LOS in hospital by 1% (relative risk [RR]: 1.010, 95% confidence interval [CI]: 1.001–1.018) and 9.3% (RR: 1.093, 95% CI: 1.051–1.138), respectively. A 1% increase in humidity variation increased the LOS in hospital for pneumonia by 2.2% (RR: 1.022, 95% CI: 1.004–1.039). In terms of economic impact, for every 1° C temperature variation during the period of hospital stay, there is an addition of 0.81 USD/day/patient as a result of direct costs and 1.8 USD/day/patient for total costs. Annually, this results in an additional 443 USD for direct and 985 USD for total costs. ConclusionsClimate variation appears to significantly contribute to the LOS in hospital for childhood pneumonia. These findings may help policymakers to develop effective disease management and prevention strategies.

A comprehensive statistical assessment of drought indices to monitor drought status in Bangladesh

In Bangladesh, drought has negative consequences on agriculture, environments, livelihood, and food security. However, a comprehensive statistical assessment of drought indices has rarely been found in the existing literature. To address this issue, firstly, this paper used daily temperature and precipitation data from the Bangladesh Meteorological Department (BMD) to calculate Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI). After that, we performed a statistical assessment, for instance, Pearson correlation coefficient, cross-correlation, cross-wavelet transform, and root mean square error, to identify the strengths of SPI and SPEI. Our findings showed that though both indices had a strong correlation with each other, SPEI performed better than SPI because evaporative demand has a positive impact on defining drought conditions in Bangladesh. Temperature and rainfall indices, for example, warm spell duration indicator (WSDI) and maximum amount of rain (Rx5day) that falls in five consecutive days, have been applied to find out the relationship between climate extremes and drought indices using cross-wavelet transform. Our results suggested that climate extremes such as WSDI and Rx5day have an influence on droughts in Bangladesh. Our results recommended that multi indices of drought assessment should be required in order to draw a robust conclusion.

Generation of IDF Equation from Catchment Delineation Using GIS

The study was intended to find out the catchment characteristics of an area and the IDF (Intensity-Duration-Frequency) analysis of rainfall of that area using Gumbel method and Log Pearson type III method. In different studies, the IDF equations are generated for an area without acknowledging the catchment, stream length of the catchment and the time of concentration. In our study the Digital Elevation Map (DEM) of Dhaka was used. The DEM was analyzed using QGIS to find out different catchments, catchment area, catchment slope, stream length etc. The rainfall data of 18 years was collected from BMD (Bangladesh Meteorological Department) at 24 hours’ interval. This rainfall data was analyzed using Gumbel method and Log Pearson Type III method because these methods give accurate prediction for return period more than the range of the acquired data. The return period was taken as 2 years,5 years,10 years,25 years,50 years and 100 years. Finally, the intensity for different return period was plotted against the duration of the rainfall to find out the IDF curve. For any kind of rainfall analysis to find the peak discharge for designing storm sewage lines, small hydraulic structures or calculating surface runoff, infiltration, sub-surface runoff, discharge at rivers or water bodies, the derived IDF equations can be used. Even to find out peak discharge with a return period more than 18 years these set of equation can be used. This method can also be used in other sub urban or urban areas to find out the time of concentration of that catchment and IDF relationships for short duration rainfalls.

Assessment of the potential Total Effective Dose (TED) and Ground Deposition (GD) following a hypothetical accident at the proposed Rooppur Nuclear Power Plant

The radiological consequences following a severe hypothetical accident at the proposed Rooppur Nuclear Power Plant in Bangladesh, have been assessed using the health physics code HotSpot 3.1, developed by Lawrence Livermore National Laboratory, USA in this study. The source term for this approach has been calculated analytically. Atmospheric dispersion characteristics have been branded using the site-specific meteorological data of 30 years, obtained from Bangladesh Meteorological Department. The TED and GD values have been calculated in the downwind distance for six individual cases along the plume centerline from the release point up to 200 km. The cases include three seasons namely Summer, Rainy and Winter with three stability classes A, B and F prevailing around the region. The highest value of TED and GD observed is for Rainy season (Stability Class F). The three TED contours have been drawn for 1.00, 0.50 and 0.05 Sv respectively which reflect dose limits for permanent relocation, emergency worker and evacuation, as established by IAEA-TECDOC-953. Demographic analysis reveals that the highest number of affected population corresponds to Rainy season, as it is more spread.

Impact of Extreme Precipitation Intensity on Tea Production in the North-East of Bangladesh

Bangladesh is a flood prone country where precipitation amount is irregular but sometimes extreme. Among the climatic parameters, precipitation is assumed as one of the vital indicators of ongoing climate change scenarios and is equally important for tea production. In this study, 7 and 9 tea estates of Sylhet and Sreemangal were selected to analyze tea production in relation to extreme precipitation intensity. Precipitation patterns namely 90th, 95th and 99th percentile were analyzed to find out the contribution of extreme precipitation and tea production. To attain the objectives, 3 hourly, daily, monthly, and total precipitation data from 1971 to 2014 were collected from Bangladesh Meteorological Department and Bangladesh Agricultural Development Board. Tea production data were collected from Bangladesh Tea Board, Sylhet. To find out extreme level of precipitation 90th, 95th, 99th percentile precipitation days were identified and analyzed. The analyses show that 1974, 1976, 1977, 1993, 1988, 1990, 2000, 2001, 2002, and 2004 were extreme precipitation years. The average precipitation of Sylhet was higher in 2000 than in 1992 and 2014. In Sreemangal, extreme precipitation was higher in 2014 than in 1992 and 2000. For both the regions, tea production was higher in 2000 and lower in 1992 and 2014. The result shows that more extreme precipitation was responsible for higher amount of tea production. The results suggest that extreme precipitation intensity was one of the responsible factors for higher amount of tea production in Sylhet and Sreemangal.

An Assessment of Spatial Distribution of Four Different Satellite-Derived Rainfall Estimations and Observed Precipitation over Bangladesh

Given that precipitation is a major component of the earth’s water and energy cycles, reliable information on the monthly spatial distribution of precipitation is also crucial for climate science, climatological water-resource research studies, and for the evaluation of regional model simulations. In this paper, four satellite derived precipitation datasets: Climate Prediction Center MORPHING (CMORPH), Tropical Rainfall Measuring Mission (TRMM), the Precipitation Estimation Algorithm from Remotely-Sensed Information using an Artificial Neural Network (PERSIANN), and the global Satellite Mapping of Precipitation (GSMaP) are spatially analyzed and compared with the observed precipitation data provided by Bangladesh Meteorological Department (BMD). For this study, the different precipitations data sets are spatially analyzed from 2nd May 2019 to 4th May 2019 at the time of Cyclone “FANI”. It is found that the satellite derived precipitation datasets are reasonably matched with the observed but slightly different.

Using Markov Analysis to Study the Impact of Temperature in Bangladesh

In this paper has been studied the temperature trend in Bangladesh. Long-term changes of surface air temperature over Bangladesh have been studied using the available historical data collected by the Bangladesh meteorological Department (BMD). Daily temperature data is collected from BMD in Dhaka and Chittagong. Then month have been divided according to season and their descriptive statistics are computed. Maximum average temperature in pre-monsoon season and minimum average temperature in winter season have been shown in the paper. This study also reveals that temperature has increased over the time. Markov chain analysis has been applied for these data so as to find the stationary probability. After 26 and 13 days stationary probabilities in Dhaka and Chittagong stations respectively have observed.

Weather factors, PCV intervention and childhood pneumonia in rural Bangladesh.

Available evidence is limited on the association between weather factors and childhood pneumonia, especially in developing countries. This study examined the effects of weather variability on childhood pneumonia after the introduction of pneumococcal conjugate vaccines (PCV) intervention in rural Bangladesh. Data on pneumonia cases and weather variables (temperature and relative humidity) between the 1st January 2012 and the 31st December 2016 were collected from Matlab Hospital, International Centre for Diarrhoeal Disease Research, Bangladesh, and Bangladesh Meteorological Department, respectively. Time series cross-correlation functions were applied to identify the time lags of the effect of each weather factor on pneumonia. Generalized linear regression model with Poisson link was used to quantify the association between weather factors and childhood pneumonia after adjustment of PCV intervention. The annual incidence rate of pneumonia reduced from 5691/100,000 to 2000/100,000 after PCV intervention. Generalized linear regression model suggested that temperature had a negative association with childhood pneumonia (relative risk, 0.985; 95% confidence interval (CI), 0.974-0.997), and PCV intervention was a protective factor with the relative risk estimate of 0.489 (95% CI, 0.435-0.551). However, no substantial association was found with relative humidity. PCV intervention appeared protective against childhood pneumonia, and temperature might be associated with this disease in children. Our findings may help inform public health policy, including the potential of development of early warning systems based on weather factors and PCV for the control and prevention of pneumonia in lower middle-income country like Bangladesh.

Synoptic flow patterns and large-scale characteristics of flash flood-producing rainstorms over northeast Bangladesh

Flash flood and related hazards occurred over the Haor (wetland) areas of northeast Bangladesh during 17–18 April 2010. Prediction of this sudden incident is challenging when it happened on the high terrain of Meghalaya Plateau and adjoining Bangladesh. Flash flood event occurred when convective cells assembled into a mesoscale convective system (MCS) over the steep edge of the Plateau. The MCS obtained its extreme point after getting moisture support from the southerly flow of the Bay of Bengal (BoB). This study investigated the synoptic flow patterns and large-scale characteristics of the flash flood-producing storm and its associated tropospheric conditions in northeast Bangladesh using the Weather Research and Forecasting (WRF) model. The model used a 3-nested domain with the horizontal resolution of 27 km, 9 km, and 3 km, respectively. The study revealed that the model underestimated the strength of the flash flood in general in respect of rainfall. The 48-h simulated rainfall was about 152 mm for outer domain-1, about 195 mm for inner domain-2 and about 209 mm for the innermost domain-3 whereas actual rainfall was 223 mm as recorded by Bangladesh Meteorological Department (BMD). The southerly wind was strong at 950 hPa and the westerly wind prevailed at 500 hPa level. The model simulated results show that cloud water mixing ratio was 1.8 mg m−3 and extended vertically up to 17 km. Ice water mixing ratio was 200 mg m−3 and found in between 12 and 20 km, indicating the formation of ice in the upper troposphere. The maximum values of x, y, and z-wind components over Cherrapunji were − 11 ms−1, − 21 ms−1 and − 2.8 ms−1, respectively which indicated the strengthening of the convective system to produce flash flood.

Outdoor PM2.5 Associations with Cardiovascular Disease Incidence in Dhaka, Bangladesh, and the Respective Roles of Fossil Fuels and Biomass Combustion

OPS 06: Health effects of source-specific outdoor air pollution, Room 117, Floor 1, August 27, 2019, 10:30 AM - 12:00 PM Rationale: Dhaka City, Bangladesh is among the cities with the highest fine particulate matter (PM2.5) air pollution levels (mean= 82 μg/m3). The assumption has been that the health effects of PM2.5 per mass is similar in the developing world as in the developed world, despite the fact that the PM2.5 pollution sources (and their particle characteristics) are different. We seek to evaluate the appropriateness of this assumption in Dhaka, Bangladesh. Methods: The analysis applied time-series generalized quasi-Poisson regression, adjusting for temporal trend, day of week, holidays, relative humidity, and temperature. Daily weather data were obtained from Bangladesh Department of Environment and Bangladesh Meteorological Department. Daily counts of cardiac emergency department visits (EDV, n= 340,758), hospitalizations (n= 253,407), and mortality (n= 16,858) were obtained from National Institute of Cardiovascular Diseases (NICVD) for September 2013 through December 2017. Results: PM2.5 yielded significant associations with increased CVD EDV [ER= 0.33%, 95% CI: 0.07, 0.59], hospitalizations [ER= 0.44%, 95%CI: 0.11, 0.78], and deaths [ER= 0.86%, 95% CI: 0.26, 1.46] per 10 μg/m3 increase, but with effect estimates per mass below those found in developed-world studies. Examining the relationship as a function of PM2.5 concentration reveals that the effect estimates are larger at lower PM2.5 concentrations, but smaller, and non-significant, at higher concentrations, when biomass (e.g., crop) burning dominates exposures. The health effects relationships followed that of sulfur, indicating that, when sulfur containing combustion (e.g., coal burning) PM2.5 does not increase, the overall PM2.5 CVD effect also is not increased, despite rising mass concentrations. Conclusion: This study provided a confirmatory evidence of the effect of air pollution on CVD morbidity and mortality in Dhaka. However, the CVD effect size varied depending on mix of air pollution sources, with biomass burning PM2.5 suggested as having a lower CVD effect per µg/m3 than fossil fuel combustion-related PM2.5.

Effects of Climate on Sandflies and Leishmaniasis in Endemic Areas of Bangladesh

Introduction: Climate includes rainfall, temperature; humidity has shown significant influences on Leishmaniasis and development of sand flies. Kala-azar- a climate-sensitive disease, a public health problem and historically endemic in Bangladesh, nurtured in temperatures ranging from 7 to 37°C, with relative humidity above 70%. Longevity and survival of vector of Kala-azar has been geographically controlled by the climate which is hard to manoeuver.&#x0D; Objective:To observe the relationship of climate and its effects on the development of sand flies and Leishmaniasis (Kala-azar) in the endemic areas in Bangladesh.&#x0D; Materials and Methods: This cross sectional study was conducted at the endemic areas of, Bangladesh during the period of 2014-2017. Information on climate like rainfall, humidity and temperature were collected from local respective Upazilla Live Stock Office and Bangladesh Meteorological Department, Agargaon, Dhaka. Month wise data of Kala-azar cases were collected from Directorate General of Health Services.&#x0D; Results: Temperature, Rainfall and Humidity are important for survivability and activity of sandfly as well asleishmaniasis. Mean temp at the study areas was found at around 20℃ in the month of Jan, Feb and Nov, Dec. Round the year the Maximum and Minimum temp was maintained at neither to high nor to low (between 7 to 36.5℃). Annual average humidity of these study area was found over 70%. In the study areas maximum rainfall 300to 500 mm was from May to Sep where peak was in Jun to Sep. Annual average rainfall was recorded 1434 to 1584 mm at Pabna and 2084 to 2182 mm at Mymensingh. Study findings correlated that rainfall may or may not have effects with sand fly and leishmaniasis. This study depicted distinct peaks of Leishmaniasis seen in pre monsoon Feb, monsoon Sep and post monsoon Nov period which dictated the plethora of sand fly from Jun to Oct and also from Jan to Feb.&#x0D; Conclusion: Manoeuvring the climate is difficult and it does not change each year, it will play its own role. We can manoeuver the harbour and the vector of leishmaniasis.Within this climatic condition National Kala-azar Elimination Programme has been fighting since 2008 but Kala-azar has not come to Zero. Further resurgence can it be outweigh?&#x0D; Journal of Armed Forces Medical College Bangladesh Vol.14(1) 2018: 10-14

Identifying Climatic Variables with Rice Yield Relationship and Land Cover Change Detection at Sylhet Region

The study is conducted to determine the correlation between climatic parameters and rice yield. The present study is also undertaken to analyze the land cover change in Sylhet district between 2013 and 2018 using LANDSAT-8 images. Local climate and rice yield data are collected from BMD (Bangladesh Meteorological Department) and BRRI (Bangladesh Rice Research Institute) and BBS (Bangladesh Bureau of Statistics). ArcGIS 10.5 and SPSS software are used to show the vegetation condition and correlation coefficient between rice yield and climatic variables respectively. It is revealed from the result that rainfall is negatively correlated with Aman and Boro (local and HYV) rice whereas temperature and relative humidity showed a positive correlation with local Aman and Boro rice. On the other hand, relative humidity showed a strong linear relationship with HYV Boro rice. Finally, both temperature and relative humidity have substantial effects on yields in the Boro rice. Furthermore, vegetation condition is observed through NDVI and found the moderate-high vegetation in 2013. After that NDVI value is fluctuating which evidently signifies the rapid vegetation cover change due to a flash flood, flood and other climate changing aspects. Additionally, Forested and high land vegetation’s are endangered rapidly. Some adaptation strategies should be followed to minimize the effects of natural calamities for improving better vegetation condition.