Members’ Publication

Urbanization has been contributing more in global climate warming, with more than 50% of the population living in cities. Rapid population growth and change in land use/land cover (LULC) are closely linked. The transformation of LULC due to rapid urban expansion significantly affects the functions of biodiversity and ecosystems, as well as local and regional climates. Improper planning and uncontrolled management of LULC changes profoundly contribute to the rise of urban land surface temperature (LST). This study evaluates the impact of LULC changes on LST for 1997, 2007 and 2017 in the Rajshahi district (Bangladesh) using multi-temporal and multi-spectral Landsat 8 OLI and Landsat 5 TM satellite data sets. The analysis of LULC changes exposed a remarkable increase in the built-up areas and a significant decrease in the vegetation and agricultural land. The built-up area was increased almost double in last 20 years in the study area. The distribution of changes in LST shows that built-up areas recorded the highest temperature followed by bare land, vegetation and agricultural land and water bodies. The LULC-LST profiles also revealed the highest temperature in built-up areas and the lowest temperature in water bodies. In the last 20 years, LST was increased about 13ºC. The study demonstrates decrease in vegetation cover and increase in non-evaporating surfaces with significantly increases the surface temperature in the study area. Remote-sensing techniques were found one of the suitable techniques for rapid analysis of urban expansions and to identify the impact of urbanization on LST.

This exploratory research examines the impacts of changing climate on the vulnerable U.S-Affiliated Pacific Islands (USAPI) from the perspective of the IPCC-Fifth Assessment Report (AR5) coupled with General Circulation Models (GCMs). Island-wide projections of future climate change (e.g., temperature, rainfall, and net water flux) were made using the latest IPCC-AR5 GCMS protocol (CMIP5) with 38 GCMs with up to 105 model runs. A review has also been made of studies on model-based future projections of El Niño –Southern Oscillation (ENSO). The CMIP5 model results clearly illustrate that the past trend in temperature (1950-2017) is rising while the rainfall trend remains more or less static. It is also clear from the projections that the long-term trend for temperature rise is fast and significant while the trend for rainfall and net water flux (P-E) rise appears to be slow and marginal. On the perspective of CMIP5 model evaluation for the USAPI region, the temperature projections are found to be promising while the rainfall projection potentials, despite some limitations, are also encouraging. The prime concerns for future disruptions in the USAPI region are the consequences of increasing frequency of ENSO and related rainfall activities. The long term warming signal may further complicate the problem. Therefore, the currently water-stressed islands and low-lying atolls in the Federated States of Micronesia (FSM) and Republic of Marshalls Islands (RMI) are particularly vulnerable to El Niño-related heat stress or drought and La Niña-related inundations or flooding. In both cases, the future demand oriented climate-sensitive water resources sector will be severely affected. A climate-information-based comprehensive water resources management plan (for 2030s) is therefore essential with more detailed ENSO-related climate information and impacts in terms people can understand and respond to.

Sustainability of transport system depends on a range of services and impacts produced by transport which can be indicated by several factors like mode choice, affordability, equity, accessibility, pollution, safety and efficiency. To address the increasing congestion problem and demand of mobility carsharing service was introduced in urban areas through focusing sustainability. Uber is a ridesharing service catered for an easy, comfortable, and convenient urban travel experience. It was launched in Dhaka in 2016. As a new alternative mode is available to the city dwellers, many of them are using it. The study intended to identify the Uber users as well as to understand their use pattern and preferences from sustainability perspective. For this study data were collected through in person questionnaire survey of Uber users at several potential points of users by random sampling method. The study has used descriptive approaches to investigate the issues. Results show that Uber is mostly used by the people of middle to high income younger age group due to its better accessibility and safety. Due to higher fare structure low to middle income people can not avail this service which is a negative point for Uber as far as sustainability is concerned. Uber trips are found most likely to be shifted from CNG and Taxi. Uber has no impact to change private car ownership status and car use. In some cases Uber has diverted trips from non-motorized modes. It is clear from the observation of this study that Uber is providing service to a particular segment of the population with less sustainability concern of urban transport in Dhaka.

Hazards like cyclone, storm surge, flood, drought, landslide, building collapse, fire etc. recurrently occur in Bangladesh due to its locational disadvantages and public ignorance regarding impacts of hazards. In this study, multi hazard assessment has been conducted and based on this result multi hazard zones have been delineated for Chittagong division of Bangladesh in case of 2013. Here the Chittagong division was selected as study area due to its geographical vulnerable location and witnessing situation at different hazards. The year 2013 has been considered as the study period because of occurrence of recurrent and various types of hazards at Chittagong division in a single period according to data. Assessment and zoning has been conducted separately both for natural and manmade hazards because of their different characteristics. Historically, Chittagong division is attacked by different hazards like cyclone, flood, landslides, fire etc. almost in every year. It has been observed from the study that Chittagong district is the most susceptible district because of multiple types of hazards. This district is vulnerable for both natural and manmade hazards. Noakhali district is also in a vulnerable state in case of natural hazards. Specific policies for specific locations may improve the scenario. This kind of hazard assessment should be incorporated in local level planning in order to develop community resilience and adaptation.