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71.
The evaporation rates over the Arabian Sea (AS) for the summer monsoon months (June to September) of 1987 have been computed using the bulk-aerodynamic formula. The satellite derived precipitation from the INSAT-1B VHRR (Very High Resolution Radiometer) sensor operating in the wavelength 10.5–12.5 m has been used for computing the precipitation over the AS. The net water vapour flux divergence (NFD) over AS has been computed as the difference between evaporation and precipitation. The estimates being -0.02 × 1010, 2.55 × 1010, 0.70 × 1010 and 0.44 × 1010 tons/day respectively for the months June, July, August and September. The NFD over AS was found to be positively and significantly correlated with the mean monsoon rainfall along the west coast of India. 相似文献
72.
V. Ramesh Babu J. S. Sastry V. V. Gopalakrishna D. V. Rama Raju 《Journal of Earth System Science》1991,100(1):55-68
The hydrographic structure in the east central Arabian Sea during premonsoon period undergoes significant temporal change
in the thermal field of upper 100 m, wherein temperature rises by about 0–5°C on an average from May to June. The major contribution
in increasing the surface layer temperature comes from surface heat exchange processes, while the horizontal advective process
tends to remove the heat from the upper layer. The geostrophic flow patterns are similar from May to June in the major part
of the study area while in the coastal areas off Goa a southerly current sets in June in response to coastal upwelling. 相似文献
73.
Suspended and bed sediments collected from the entire region of the Krishna River and its major tributaries were analyzed for heavy metals (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Pb) by the thin-film energy dispersive x-ray fluorescence technique. There is considerable variation in the concentration of elements towards downstream, which may be due to the variation in the subbasin geology and various degrees of human impact. Suspended particles are enriched in heavy metals throughout the basin relative to bed sediments. The heavy metals are enriched in coarse size fractions (10–90 µm) throughout the Krishna River except its tributary Bhima, where finer fractions (2 µm) dominate. Transition elements correlate very well with each other. There is a striking similarity between the bed sediments of Krishna River and the Indian average. When the annual heavy metal flux carried by the Krishna River was estimated, and viewed in relation to the other major riverine transport, the Krishna is seen to be a minor contributor of heavy metals to the Bay of Bengal. 相似文献
74.
75.
76.
Since 1980, many of the state governments in India have introduced programmes to integrate traditional medical systems (TM) into official health care institutions and services at different administrative levels. One of these schemes is at Primary Health Centres (phcs) in various districts. However, little research has been undertaken to date on relative demand and utilization, or on the extent to which TM is seen or used as a complement, alternative or supplement to biomedical services, in the same phc setting. The consumer assumes an important role in an integrated approach, where illness behaviour is understood to be a decision-making process. From the structuralist aspect also, the needs and decisions (in a given situation) as perceived by the administration are not necessarily the same as subjectively felt needs, wants, or even expressed needs of individuals. It is hoped research into the degree of usage and levels of clinical utilization of the two coexisting services will be useful in planning norms and services, estimation of recurrent expenditures and allocation of resources for effective functioning of the phcs. This paper presents the findings of a questionnaire based on a quota sample of users of phcs. eighty patients in each of the Allopathy and Siddha medicine wings were interviewed in three phcs in Tamil Nadu, a total of 480 respondents. The main issues considered in this paper are:
- Socio-economic characteristics of the users.
- Treatment patterns: differential preferences for treatment methods for various disease conditions; multiple-usage — interchangeable or concurrently for the same ailment; degree of medical pluralism; spatial patterns of movement.
- The reasons for participating in the present treatment.
- Behaviour, satisfaction, attitudes, opinions, preferences, experiences.
- Conclusions and implications of the study for research and service planning.
77.
Understanding the influences of local hydroclimatology and two large-scale oceanic-atmospheric oscillations (i.e., Atlantic Multidecadal Oscillation (AMO) and El Niño-Southern Oscillation (ENSO)) on seasonal precipitation (P) and temperature (T) relationships for a tropical region (i.e., Florida) is the focus of this study. The warm and cool phases of AMO and ENSO are initially identified using sea surface temperatures (SSTs). The associations of SSTs and regional minimum, maximum and average surface air temperatures (SATs) with precipitation are then evaluated. The seasonal variations in P-SATs and P-SSTs associations considering AMO and ENSO phases for sites in (1) two soil temperature regimes (i.e., thermic and hyperthermic); (2) urban and non-urban regions; and (3) regions with and without water bodies, are analysed using two monthly datasets. The analyses are carried out using trend tests, two association measures, nonparametric and parametric statistical hypothesis tests and kernel density estimates. Decreasing (increasing) trend in precipitation (SATs) is noted in the recent multi-decadal period (1985–2019) compared to the previous one (1950–1984) indicating a progression towards warmer and drier climatic conditions across Florida. Spatially and temporally non-uniform variations in the associations of precipitation with SATs and SSTs are noted. Strong positive (weak negative) P–T associations are noted during the wet (dry) season for both AMO phases and El Niño, while significant (positive) P–T associations are observed across southern Florida during La Niña in the dry season. The seasonal influences are predominant in governing the P–T relationship over the regions with and without water bodies; however, considerable variations between El Niño and La Niña are noted during the dry season. The climate variability influences on P–T correlations for hyperthermic and thermic soil zones are found to be insignificant (significant) during the wet (dry) season. Nonparametric clustering is performed to identify the spatial clusters exhibiting homogeneous P–T relationships considering seasonal and climate variability influences. 相似文献
78.
Ramesh Dhungel Robert Aiken Paul D. Colaizzi Xiaomao Lin Dan O'Brien R. Louis Baumhardt David K. Brauer Gary W. Marek 《水文研究》2019,33(15):2110-2130
The backward‐averaged iterative two‐source surface temperature and energy balance solution (BAITSSS) model was developed to calculate evapotranspiration (ET) at point to regional scales. The BAITSSS model is driven by micrometeorological data and vegetation indices and simulates the water and energy balance of the soil and canopy sources separately, using the Jarvis model to calculate canopy resistance. The BAITSSS model has undergone limited testing in Idaho, United States. We conducted a blind test of the BAITSSS model without prior calibration for ET against weighing lysimeter measurements, net radiation, and surface temperature of drought‐tolerant corn (Zea mays L. cv. PIO 1151) in a semiarid, advective climate (Bushland, Texas, United States) in 2016. Later in the season (20 days), BAITSSS consistently overestimated ET by up to 3 mm d?1. For the entire growing season (127 days), simulated versus measured ET resulted in a 7% error in cumulative ET, RMSE = 0.13 mm h?1, and 1.70 mm d?1; r2 = 0.66 (daily) and r2 = 0.84 (hourly); MAE = 0.08 mm h?1 and 1.24 mm d?1; and MBE = 0.02 mm h?1 and 0.58 mm d?1. The results were comparable with thermally driven instantaneous ET models that required some calibration. Next, the initial soil water boundary condition was reduced, and model revisions were made to resistance terms related to incomplete cover and assumption of canopy senescence. The revisions reduced discrepancies between measured and modelled ET resulting in <1% error in cumulative ET, RMSE = 0.1 mm h?1, and 1.09 mm d?1; r2 = 0.86 (daily) and r2 = 0.90 (hourly); MAE = 0.06 mm h?1 and 0.79 mm d?1; and MBE = 0.0 mm h?1 and 0.17 mm d?1 and generally mitigated the previous overestimation. The advancement in ET modelling with BAITSSS assists to minimize uncertainties in crop ET modelling in a time series. 相似文献
79.
Shivhare Vikash Gupta Chanchal Mallick Javed Singh Chander Kumar 《Natural Hazards》2022,110(1):545-561
Natural Hazards - Geographical information system and remote sensing are proven to be an efficient tool for locating water harvesting and recharge structures, groundwater potential, runoff,... 相似文献
80.
Meena Sansar Raj Soares Lucas Pedrosa Grohmann Carlos H. van Westen Cees Bhuyan Kushanav Singh Ramesh P. Floris Mario Catani Filippo 《Landslides》2022,19(5):1209-1229
Landslides - Event-based landslide inventories are essential sources to broaden our understanding of the causal relationship between triggering events and the occurring landslides. Moreover,... 相似文献