A synoptic-climatic study of the onset of southwest monsoon over Mumbai

Surface and upper air synoptic features prevailing at the time of onset of southwest monsoon over Mumbai have been examined for a period of 50 years from 1947 to 1996. These synoptic situations have been found to fall under three broad categories. The study shows that on about 66% of the occasions, the onset of monsoon over Mumbai is caused by low pressure area forming over southeast and east central Arabian Sea as they move northwards, while on 28% of the occasions, the onset is due to the low pressure systems forming over northwest/head Bay of Bengal and their movement towards northwest/west northwest. Based on the findings of the study and the climatological aspects, a criterion for declaring onset over Mumbai has been suggested.     

Urban land consolidation: a review of policy and procedures in Indonesia and other Asian countries

Many Asian mega-cities are growing rapidly and they face formidable urban problems: unplanned squatter settlements, inadequate infrastructure and basic amenities. Smaller Asian urban areas also need badly the provision of basic infrastructure and facilities. However, efforts to improve are often constrained by either nonavailability of suitable land or its exorbitant cost. Strategies such as land consolidation have shown considerable promise. Implementation of the strategy varies from country to country and from project to project. In general, the land consolidation approach is participatory in nature and places emphasis on in situ development with voluntary contribution of private assets by affected households in need of infrastructure and basic services. However, to make any significant impact of the land consolidation strategy on urban development, financial support from multilateral agencies such as the World Bank is necessary. To enable this it is necessary that the policy and implementation procedures fully conform to the objectives of the World Bank's safeguard policies such as OD 4.30 `Involuntary Resettlement'. This study reviews the land consolidation policies and procedures as applied in several Asian countries in general, and in Indonesia in particular. The objective is to identify the gaps that exist between the policy and procedures and that of the objectives of the World Bank's Policy of Involuntary resettlement and to recommend general policy and procedural guidelines for land consolidation projects that would enable financial support from multilateral agencies such as the World Bank. This revised version was published online in July 2006 with corrections to the Cover Date.     

The flattening of the X-ray spectrum of sco X-1 at energies beyond 40 keV

The measurements of the hard X-ray spectrum of Sco X-1 in the energy interval 20–150 keV in three balloon flights from Hyderabad, India are reported. These results show conclusively that the spectrum of Sco X-1 is very flat in the energy interval 40–150 keV and the measured fluxes beyond 60 keV are several orders of magnitude higher than those expected on the basis of an extrapolation of bremsstrahlung spectrum from a thin hot plasma at a temperature corresponding tokT=5 keV, which is applicable for Sco X-1 for energies <40 keV. The results are compared with those of other investigators of hard X-rays from Sco X-1, and the implication of the results is briefly discussed.     

Seismotectonic and liquefaction studies of an industrial site in Northern India

Foundation soil of the proposed fertiliser complex in Northern India is examined for its susceptibility to liquefaction during an earthquake. Information on geotectonic set up and earthquake occurrences in the region around the site is used for defining the earthquake parameters of the ground motion. The effective peak ground acceleration for the site is estimated to be of the order of 0.15 g. Laboratory tests were carried out on soil samples obtained from the site on a horizontal vibration table. The test results were used in determining the possibility of liquefaction employing the methodology developed at the Department of Earthquake Engineering, University of Roorkee. About 10 m of a thick soil layer below the top 1.5 m stiff clay is likely to liquefy. Remedial measures used at the site to counter the possibility of liquefaction are mentioned.     

MAGSAT data and Curie-depth below Deccan flood basalts (India)

Ground and airborne magnetic data are severely disturbed due to random susceptibility variations in Deccan flood basalts. However, Magnetic Satellite (MAGSAT) data over the Deccan flood basaltic region of the Indian subcontinent exhibit filtering of surficial noise. Three passes over Deccan traps show a low at about 20°N latitude and a high at about 23°N latitude. Spectral analysis of these passes and an available 2-D MAGSAT vertical intensity map indicate a deep (40±4 km) magnetic interface. It is interesting to note that the determination of Curie-depth from MAGSAT matches and confirms the geothermal data model. The estimates correspond to the Moho depth derived from gravity and deep seismic sounding studies. The study suggests a continental shield-like geothermal gradient of about 14°C/km below the area.     

Infrared and Raman spectra of lunar samples from Apollo 11, 12 and 14

We report the room temperature infrared reflectance spectra of several lunar surface rocks in the form of polished slices or butt ends. The spectra were obtained over the frequency range 20-2000 cm^–1 throughout the mid and far infrared (5-500µ) region of the electromagnetic spectrum where the fundamental internal and lattice vibrational modes of all minerals and rocks occur.Some fines samples were examined as pressed pellets and their reflectivities compared with the bulk samples. Several terrestrial minerals and rocks were also investigated. Kramers-Kronig analyses of these reflectance spectra were undertaken and the dispersion of the dielectric response ( and ) and the optical constants (n andk) have been determined over this frequency range. The low frequency and high frequency (infrared) dielectric constants were also calculated from the reflectance data.Raman light scattering measurements were made on all the samples supplied from the first three Apollo missions. Large background scattering proved to be the greatest experimental problem. Successful spectra in nearly all cases were obtained from small crystalline inclusions imbedded in the main ground mass. Some crystalline bulk rocks containing many very fine inclusions gave identifiable spectra and at least three different types were obtained.Supported by NASA Grant NGR 22-011-069 and by a Northeastern University Grant for Basic Research.     

The spectrum of diffuse cosmic X-rays in the 20–125 keV range

Diffuse cosmic X-rays in the energy range 20–125 keV were measured in four balloon flights from Hyderabad, India during 1968–70 using almost identical X-ray telescopes mounted on oriented platforms. The results from these flights show that the spectrum of the diffuse cosmic X-rays can be represented by the form dN/dE=29E ^–2.1±0.3 photons/(cm² sr s keV) in 20–125 keV interval after corrections for photoelectric absorption and Compton scattering effects in the atmosphere. The best fit spectrum of all published results in the energy interval 20–200 keV can be represented by the form dN/dE=36E ^–2.1±0.1 photons/(cm² sr s keV) after similar corrections are effected, and there is no need for a change of spectral index in this energy interval. The intensity at 20 keV obtained from the above spectrum agrees well with that given by the spectral form dN/dE=10E ^–1.7±0.1 photons/(cm² sr s keV) in the energy interval 1–20 keV in several rocket experiments. Therefore it is concluded that if there is a break in the spectrum, it occurs between 10 and 20 keV with a change of spectral index by about 0.5, or the index is continuously changing from 1.7±0.1 to 2.1±0.1 in 10–20 keV interval. The implications of the results are briefly discussed.     

Hydromagnetic Ekman layer on free convection past an infinite porous flat plate

Free convection in a conducting liquid past an infinite porous vertical flat plate in a rotating frame of reference when the Hall current is present is considered. Exact solutions for the velocity and temperature fields have been derived. The effects ofM (Hartmann number),m (Hall parameter), andE (Ekman number) on the velocity field are discussed.Nomenclature C _p specific heat at constant pressure - g acceleration due to gravity - E Ekman number - G Grashof number - H ₀ applied magnetic field - j _x ,j _y ,j _z components of the current densityJ - k thermal conductivity - M Hartmann number - m Hall parameter - P Prandtl number - Q heat flux per unit area - T temperature of the fluid near the plate - T _w temperature of the plate - T temperature of the fluid in the free-stream - u, v, w components of the velocity fieldq - U uniform free-stream velocity - w ₀ suction velocity - x, y, z Cartesian coordinates - z dimensionless coordinate normal to the plate Greek symbols coefficient of volume expansion - _e cyclotron frequency - _e electron collision time - _u skin friction in the direction ofu - _v skin friction in the direction ofv - dimensionless temperature - density of the fluid - kinematic viscosity - _e magnetic permeability - electrical conductivity of the fluid - angular velocity     

Climate adaptation,local institutions,and rural livelihoods: A comparative study of herder communities in Mongolia and Inner Mongolia,China

Climate variability has been evident on the Mongolian plateau in recent decades. Livelihood adaptation to climate variability is important for local sustainable development. This paper applies an analytical framework focused on adaptation, institutions, and livelihoods to study climate adaptation in the Mongolian grasslands. A household survey was designed and implemented in each of three broad vegetation types in Mongolia and Inner Mongolia. The analytical results show that livelihood adaptation strategies of herders vary greatly across the border between Mongolia and Inner Mongolia, China. Local institutions played important roles in shaping and facilitating livelihood adaptation strategies of herders. Mobility and communal pooling were the two key categories of adaptation strategies in Mongolia, and they were shaped and facilitated by local communal institutions. Storage, livelihood diversification, and market exchange were the three key categories of adaptation strategies in Inner Mongolia, and they were mainly shaped and facilitated by local government and market institutions. Local institutions enhanced but also at times undermined adaptive capacity of herder communities in the two countries, but in different ways. Sedentary grazing has increased livelihood vulnerability of herders to climate variability and change. With grazing sedentarization, the purchase and storage of forage has become an important strategy of herders to adapt to the highly variable climate. The multilevel statistical models of forage purchasing behaviors show that the strategies of livestock management, household financial capital, environmental (i.e., precipitation and vegetation growth) variability, and the status of pasture degradation were the major determinants of this adaptation strategy.     

Zircon U‐Pb/Lu‐Hf and monazite chemical dating of the Tirodi biotite gneiss: implication for latest Palaeoproterozoic to Early Mesoproterozoic orogenesis in the Central Indian Tectonic Zone

In this investigation, we reconstruct the latest Palaeoproterozoic to Early Mesoproterozoic orogenic events along the southern margin of the Central Indian Tectonic Zone (CITZ), using sensitive high resolution ion microprobe (SHRIMP) U‐Pb zircon dating and Lu‐Hf isotope analyses of zircon and Th‐U‐Pb chemical dating of monazite from samples of the Tirodi biotite gneiss (TBG) unit in the Sausar Mobile Belt (SMB), the latter constituting the southernmost litho‐tectonic component of the CITZ. U‐Pb zircon dating of one migmatitic gneiss sample from the type locality of the Tirodi biotite gneiss in the northern domain of the SMB has yielded an age of 1618 ± 8 Ma, which is considered to be the time of magmatic crystallization of its protolith. Combined U‐Pb zircon and monazite chemical dating of two granite gneiss samples from the southern domain of the SMB broadly constrain magmatic crystallization between 1603 ± 23 Ma and 1584 ± 17 Ma and an overprinting metamorphic recrystallization event at 1572 ± 7 Ma. Monazites from the granite gneiss samples also record a terminal metamorphic event at 1415 ± 23 Ma. Lu‐Hf isotopic analyses of zircons reveal fundamentally different source rock reservoirs for the protoliths of these magmatic rocks across the SMB. While the type TBG from the northern domain was derived from an Early Palaeoproterozoic source T(Hf) from 2093 to 2523 Ma, with a mean value at 2379 Ma) of essentially juvenile material with minor crustal components (εHf(t) from −3.3 to + 3.7), the granite from the southern domain had a mature crustal source (εHf(t) from −12.5 to −21.9) of Palaeoarchaean age T(Hf) from 3051 to 3630 Ma, with a mean value at 3218 Ma). When integrated with metamorphic information previously obtained from the 1.6 Ga ultra‐high temperature granulite facies metamorphic event in the SMB, the discrete magmatic and metamorphic events between 1.62/1.60 Ga and 1.42 Ga can be correlated with the formation of an Early Mesoproterozoic accretionary orogen in the CITZ. Copyright © 2011 John Wiley & Sons, Ltd.