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The role of glaciers in stream flow from the Nepal Himalaya  [PDF]
D. Alford,R. Armstrong
The Cryosphere Discussions , 2010, DOI: 10.5194/tcd-4-469-2010
Abstract: Recent concerns related to the potential impacts of the retreat of Himalayan glaciers on the hydrology of rivers originating in the catchment basins of the Himalaya have been accompanied by few analyses describing the role of glaciers in the hydrologic regime of these mountains. This is, at least in part, a result of the relative inaccessibility of the glaciers of the Himalaya, at altitudes generally between 4000–7000 m, and the extreme logistical difficulties of: 1) reaching the glaciers, and 2) conducting meaningful research once they have been reached. It is apparent that an alternative to traditional "Alpine" glaciology is required in the mountains of the Hindu Kush-Himalaya region. The objectives of the study discussed here have been to develop methodologies that will begin to quantify the role of complete glacier systems in the hydrologic regime of the Nepal Himalaya, and to develop estimates of the potential impact of a continued retreat of these glacier, based on the use of disaggregated low-altitude data bases, topography derived from satellite imagery, and simple process models of water and energy exchange in mountain regions. While the extent of mesoscale variability has not been established by studies to date, it is clear that the dominant control on the hydrologic regime of the tributaries to the Ganges Basin from the eastern Himalaya is the interaction between the summer monsoon and the 8000 m of topographic relief represented by the Himalayan wall. All the available evidence indicates that the gradient of specific runoff with altitude resulting from this interaction is moderately to strongly curvilinear, with maximum runoff occurring at mid-altitudes, and minima at the altitudinal extremes. At the upper minimum of this gradient, Himalayan glaciers exist in what has been characterized as an "arctic desert". The methodologies developed for this study involve the relationship between area-altitude distributions of catchment basins and glaciers, based on Shuttle Radar Topography Mission (SRTM3) data and water and energy exchange gradients. Based on these methodologies, it is estimated that the contribution of glacier annual melt water to annual stream flow into the Ganges Basin from the glacierized catchments of the Nepal Himalaya represents approximately 4% of the total annual stream flow volume of the rivers of Nepal, and thus, is a minor component of the annual flow of the Ganges River. The models developed for this study indicate that neither stream flow timing nor volume of the rivers flowing into the Ganges Basin from Nepal will be affe
Implementation of a process-based catchment model in a poorly gauged, highly glacierized Himalayan headwater
M. Konz, S. Uhlenbrook, L. Braun, A. Shrestha,S. Demuth
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2007,
Abstract: The paper presents a catchment modeling approach for remote glacierized Himalayan catchments. The distributed catchment model TACD, which is widely based on the HBV model, was further developed for the application in highly glacierized catchments on a daily timestep and applied to the Nepalese Himalayan headwater Langtang Khola (360 km2). Low laying reference stations are taken for temperature extrapolation applying a second order polynomial function. Probability based statistical methods enable bridging data gaps in daily precipitation time series and the redistribution of cumulated precipitation sums over the previous days. Snow and ice melt was calculated in a distributed way based on the temperature-index method employing calculated daily potential sunshine durations. Different melting conditions of snow and ice and melting of ice under debris layers were considered. The spatial delineation of hydrological response units was achieved by taking topographic and physiographic information from maps and satellite images into account, and enabled to incorporate process knowledge into the model. Simulation results demonstrated that the model is able to simulate daily discharge for a period of 10 years and point glacier mass balances observed in the research area with an adequate reliability. The simple but robust data pre-processing and modeling approach enables the determination of the components of the water balance of a remote, data scarce catchment with a minimum of input data.
Tradeoffs for the implementation of a process-based catchment model in a poorly gauged, highly glacierized Himalayan headwater
M. Konz,S. Uhlenbrook,L. Braun,A. Shrestha
Hydrology and Earth System Sciences Discussions , 2006,
Abstract: The paper presents a catchment modeling approach for remote glacierized Himalayan catchments. The distributed catchment model TACD, which is widely based on the HBV model, was further developed for the application in highly glacierized catchments on a daily timestep and applied to the Nepalese Himalayan headwater Langtang Khola (360 km2). Low laying reference stations are taken for temperature extrapolation applying a second order polynomial function. Probability based statistical methods enable bridging data gaps in daily precipitation time series and the redistribution of cumulated precipitation sums over the previous days. Snow and ice melt was calculated in a distributed way based on the temperature-index method employing calculated daily potential sunshine durations. Different melting conditions of snow and ice and melting of ice under debris layers were considered. The spatial delineation of hydrological response units was achieved by taking topographic and physiographic information from maps and satellite images into account, and enabled to incorporate process knowledge into the model. Simulation results demonstrated that the model is able to simulate daily discharge for a period of 10 years and point glacier mass balances observed in the research area with an adequate reliability. The simple but robust data pre-processing and modeling approach enables the determination of the components of the water balance of a remote, data scarce catchment with a minimum of input data.
Key Climatic Variables And Respiratory illness  [cached]
Ramachandran G,Pratinidhi Asha,Karkrani Vandana,Garad S G
Indian Journal of Community Medicine , 1999,
Abstract: Research Question: Is there any correlation between climatic variables and pattern of respiratory illness in Pune city. Objective: To correlate the Key variables of climate with the pattern of respiratory illness in Pune City. Study design: Correlational study. Setting: Recorded date about cases of respiratory illness from CGHS dispensaries. Outcome measure: Respiratory illness. Study Variable: Air temperature, diurnal variation, humidity, Statistical analysis: Correlation. Results: It was observed that there is a negative correlational of temperature with the streptococcal sore throat (n = -0.35), asthma (r = -0.34) as well as with the non-specific respiratory illness(r = -0.34). Similarly numbers of streptococcal sore throat cases were maximum with the maximum diurnal variation (r = 0.3). There was no significant correlation observed between respiratory illness and the range of relative.
Defining the climatic signal in stream salinity trends using the Interdecadal Pacific Oscillation and its rate of change
V. H. McNeil,M. E. Cox
Hydrology and Earth System Sciences Discussions , 2006,
Abstract: The impact of landuse on stream salinity is difficult to separate from decadal climatic variability, as the decadal scale climatic cycles in ground water and stream hydrology have similar wavelengths to the landuse pattern. These hydrological cycles determine the stream salinity through accumulation or release of salt in the landscape. The Interdecadal Pacific Oscillation (IPO) has been investigated before as an indicator of hydrological and related time series in the southern hemisphere. This study presents a new approach, which uses the rate of change in the IPO, rather than just its absolute value, to define an indicator for the climate component of ambient shallow groundwater tables and corresponding stream salinity. Representative time series of water table and stream salinity indicators are compiled, using an extensive but irregular database covering a very wide geographical area. These are modelled with respect to the IPO and its rate of change to derive climatic indicators. The effect of removing the decadal climatic influence from stream salinity trends is demonstrated.
Defining the climatic signal in stream salinity trends using the Interdecadal Pacific Oscillation and its rate of change
V. H. McNeil,M. E. Cox
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2007,
Abstract: The impact of landuse on stream salinity is currently difficult to separate from the effect of climate, as the decadal scale climatic cycles in groundwater and stream hydrology have similar wavelengths to the landuse pattern. These hydrological cycles determine the stream salinity through accumulation or release of salt in the landscape. Widespread patterns apparent in stream salinity are discussed, and a link is demonstrated between stream salinity, groundwater levels and global climatic indicators. The Interdecadal Pacific Oscillation (IPO) has previously been investigated as a contributory climatic indicator for hydrological and related time series in the Southern Hemisphere. This study presents an approach which explores the rate of change in the IPO, in addition to its value, to define an indicator for the climate component of ambient shallow groundwater levels and corresponding stream salinity. Composite time series of groundwater level and stream salinity are compiled using an extensive but irregular database covering a wide geographical area. These are modelled with respect to the IPO and its rate of change to derive control time series. A example is given of how a stream salinity trend changes when the decadal climatic influence is removed.
Spatial distribution analysis on climatic variables in northeast China
SHANG Zong Bo,GAO Qiong,YANG Dian An,YANG Zheng Yu,
SHANG Zong-Bo
,GAO Qiong,YANG Dian-An,YANG Zheng-Yu

环境科学学报(英文版) , 2001,
Abstract: Information ecology is a new research area of modern ecology. Here describes the spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction in Northeast China. First, digital terrain models was built with large scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2) mean monthly data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climatic variables.
Climatic variables and malaria incidence in Dehradun, Uttaranchal, India  [PDF]
N. Pemola Devi ; R.K. Jauhari
Journal of Vector Borne Diseases , 2006,
Abstract: Background & objectives: Mosquito-borne diseases particularly malaria and Japanese encephalitis(JE) are becoming most dreaded health problems in Dehradun district. Keeping in view that theclimatic factors particularly temperature and rainfall may alter the distribution of vector species–increasing or decreasing the ranges, depending on weather conditions that are favourable orunfavourable for mosquito breeding, it is aimed to find out the effect of climatic factors on malariaincidence with particular emphasis to capture the essential events as a result of climatic variability.Methods: Mosquito sampling and identification was done using WHO entomological methods andfollow-up of recognised keys and catalogues. Data on malaria incidence and meteorologicalinformation were gathered in a collaborative study with the District Malaria Office, and the ForestResearch Institute, Dehradun respectively. Pearson’s correlation analysis was applied for establishingrelationship between climate variables and malaria transmission.Results: Higher positive correlation of association was found between monthly parasite incidenceand climatic variables (temperature, rainfall and humidity). However, highest significant correlationwas found between rainfall and malaria incidence (r = 0.718, p < 0.0001) when the data were staggeredto allow a lag of one-month.Interpretation & conclusion: Climatic variables that predict the presence or absence of malaria arelikely to be the best suited for forecasting the distribution of this disease at the edges of its range
Evidence for Himalayan remagnetization in Tarim Basin
Dajun Fang,Zhongyue Shen,Xiaodong Tan
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9143
Abstract: Himalayan remagnetization in the Tarim Basin was found to be widespread in Paleozoic, Mesozoic and Cenozoic rocks. Rock magnetism was performed to study the magnetic carriers. The authors believe that tectonic fluid in the Himalayan stage caused the rock remagnetization. The framboidal pyrites in bitumen and hydrocarbon-rich rocks may transform to framboidal magnetite in the later alkali environment, which leads to remagnetization.
THE EFFECTS OF CLIMATIC VARIABLES AND CROP AREA ON MAIZE YIELD AND VARIABILITY IN GHANA
Henry De-Graft Acquah,Clement Kweku Kyei
Russian Journal of Agricultural and Socio-Economic Sciences , 2012,
Abstract: Climate change tends to have negative effects on crop yield through its influence on crop production. Understanding the relationship between climatic variables and crop area on the mean and variance of crop yield will facilitate development of appropriate policies to cope with climate change. This paper examines the effects of climatic variables and crop area on the mean and variance of maize yield in Ghana. The Just and Pope stochastic production function using the Cobb-Douglas functional form was employed. The results show that average maize yield is positively related to crop area and negatively related to rainfall and temperature. Furthermore, increase in crop area and temperature will enlarge maize yield variability while rainfall increase will decrease the variability in maize yield.
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