Rain gages data represents limited spatial coverage, especially in rugged terrains like Lebanon. Other precipitation data sources are the developing satellite and radar technologies. In this study, Tropical Rain Measu...Rain gages data represents limited spatial coverage, especially in rugged terrains like Lebanon. Other precipitation data sources are the developing satellite and radar technologies. In this study, Tropical Rain Measurement Mission (TRMM) monthly rainfall data of 18 years (1998-2014 and 2017) was used to understand monthly and yearly precipitation spatial distribution overall Lebanon. Topographic effect of rainfall spatial distribution was investigated in comparison to Plassard’s map of 1971. The annual precipitation over the country ranged between 850 mm and 200 mm that differs than the existing historical map. The maximum rainfall rate decreased by about 700 mm between the derived TRMM rainfall map and Plassard’s one. Spatial distribution of maximum precipitation rates does not coincide between maps. TRMM map of elevated terrains did not show similar trends of rainfall distribution as Plassard’s. Pixels (Lebanon was divided into 27 pixels) of lower rainfall rates was found toward the eastern side of Lebanon, in contrast to Plassard’s results. Anti-Lebanon did not show an increase in precipitation in accordance to altitude. Spatial variability of precipitation was about 50 mm between pixels which reveals the importance of considering topography while implemented rain gages as observation points. TRMM and satellite rainfall data aid in investigating complete spatial distribution of rainfall over continuous periods. Accumulating knowledge of spatial rainfall distribution on timely basis will lead to better future modelling on floods and drought conditions in Lebanon.展开更多
The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of ...The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of the corridor three steps, initial study, field investigation, and data analysis and presentation were carried out. In the initial study, the collection of available data and review of the literature were done. The base map was then prepared from the topographical map. In the field investigation step, all information and maps prepared earlier in the initial study were verified by field check. In the final step, prepared and verified data were then analyzed for the hazard mapping. Topography (gradient, slope shape and slope aspect), geology, drainage and land-use were considered to be the major influencing factors in the slope stability. Pre-assigned hazard rating method was used for hazard mapping of the study area. The area was divided into equal facets. Then ratings of responsible factors to the hazard were assigned to each facet and overlaid based upon a predetermined rating scheme. Total estimated hazard was the sum of these ratings for each overlay. Hazard map was prepared by using three categories as low hazard, medium hazard and high hazard. The Geographic Information System (GIS) was the main tool for the data input, analysis, and preparing of the final hazard map. The hazard map showed the areas of different hazard potential classes of;“low” with 32% portion, “Medium” with 51%, and “high” with 17% portion.展开更多
Barito Delta morphodynamic had contradictive role with its potency and problem. Potency in Barito Delta may support the development of Banjarmasin City, but development of Barito Delta may decrease the capacity of tra...Barito Delta morphodynamic had contradictive role with its potency and problem. Potency in Barito Delta may support the development of Banjarmasin City, but development of Barito Delta may decrease the capacity of transportation in Barito River. Multitemporal topographic map and Landsat satellite image during the period 1862-2008 were used to analyze the long-term delta morphodynamic. The analysis consisted of delta growth, yearly growth, growth orientation, delta shape, and shoreline changes. The research showed that the Barito Delta had developed during the period 1862-2008. Barito Delta had developed to south orientation. The growth of Barito Delta during the period 1862-1946 was 27.82 km^2 or 0.33 km^2/year. However, during the period 1946-1997, Barito Delta growth was 175.82 km^2 or 3.45 km^2/year. Area of Barito Delta decreased during the period 1997-2004. The reduction of Barito Delta area was 4.73 km^2 or 0.67 km^2/year. Area of Barito Delta in years 2004-2008 increased about 3.38 km^2 or 0.84 km^2/year Shoreline during the period 1862-2008 had changed. Accretion occurred in Kuala Lupak River during the period 1862-1997, but erosion occurred during the period 1997-2004. The delta morphodynamics were influenced by human activities in watershed and delta such as landuse change and land degradation.展开更多
文摘Rain gages data represents limited spatial coverage, especially in rugged terrains like Lebanon. Other precipitation data sources are the developing satellite and radar technologies. In this study, Tropical Rain Measurement Mission (TRMM) monthly rainfall data of 18 years (1998-2014 and 2017) was used to understand monthly and yearly precipitation spatial distribution overall Lebanon. Topographic effect of rainfall spatial distribution was investigated in comparison to Plassard’s map of 1971. The annual precipitation over the country ranged between 850 mm and 200 mm that differs than the existing historical map. The maximum rainfall rate decreased by about 700 mm between the derived TRMM rainfall map and Plassard’s one. Spatial distribution of maximum precipitation rates does not coincide between maps. TRMM map of elevated terrains did not show similar trends of rainfall distribution as Plassard’s. Pixels (Lebanon was divided into 27 pixels) of lower rainfall rates was found toward the eastern side of Lebanon, in contrast to Plassard’s results. Anti-Lebanon did not show an increase in precipitation in accordance to altitude. Spatial variability of precipitation was about 50 mm between pixels which reveals the importance of considering topography while implemented rain gages as observation points. TRMM and satellite rainfall data aid in investigating complete spatial distribution of rainfall over continuous periods. Accumulating knowledge of spatial rainfall distribution on timely basis will lead to better future modelling on floods and drought conditions in Lebanon.
文摘The aim of this project was to prepare and study a hazard map of Nagadhunga-Naubise section of the Tribhuvan highway. This section lies in the Middle Mountain region of Nepal. For the preparation of the hazard map of the corridor three steps, initial study, field investigation, and data analysis and presentation were carried out. In the initial study, the collection of available data and review of the literature were done. The base map was then prepared from the topographical map. In the field investigation step, all information and maps prepared earlier in the initial study were verified by field check. In the final step, prepared and verified data were then analyzed for the hazard mapping. Topography (gradient, slope shape and slope aspect), geology, drainage and land-use were considered to be the major influencing factors in the slope stability. Pre-assigned hazard rating method was used for hazard mapping of the study area. The area was divided into equal facets. Then ratings of responsible factors to the hazard were assigned to each facet and overlaid based upon a predetermined rating scheme. Total estimated hazard was the sum of these ratings for each overlay. Hazard map was prepared by using three categories as low hazard, medium hazard and high hazard. The Geographic Information System (GIS) was the main tool for the data input, analysis, and preparing of the final hazard map. The hazard map showed the areas of different hazard potential classes of;“low” with 32% portion, “Medium” with 51%, and “high” with 17% portion.
文摘Barito Delta morphodynamic had contradictive role with its potency and problem. Potency in Barito Delta may support the development of Banjarmasin City, but development of Barito Delta may decrease the capacity of transportation in Barito River. Multitemporal topographic map and Landsat satellite image during the period 1862-2008 were used to analyze the long-term delta morphodynamic. The analysis consisted of delta growth, yearly growth, growth orientation, delta shape, and shoreline changes. The research showed that the Barito Delta had developed during the period 1862-2008. Barito Delta had developed to south orientation. The growth of Barito Delta during the period 1862-1946 was 27.82 km^2 or 0.33 km^2/year. However, during the period 1946-1997, Barito Delta growth was 175.82 km^2 or 3.45 km^2/year. Area of Barito Delta decreased during the period 1997-2004. The reduction of Barito Delta area was 4.73 km^2 or 0.67 km^2/year. Area of Barito Delta in years 2004-2008 increased about 3.38 km^2 or 0.84 km^2/year Shoreline during the period 1862-2008 had changed. Accretion occurred in Kuala Lupak River during the period 1862-1997, but erosion occurred during the period 1997-2004. The delta morphodynamics were influenced by human activities in watershed and delta such as landuse change and land degradation.
