scholarly journals Spectral (direct) solar irradiance at Pune

MAUSAM ◽  
2021 ◽  
Vol 49 (4) ◽  
pp. 487-492
Author(s):  
R. D. VASHISTHA ◽  
R. MADAN ◽  
S. K. SRIVASTAV

Direct Solar Irradiation (DSI) measurements are made with pyrheliometers. When used with selected filters, the spectral distribution can be worked out. Measurements at Pune indicate that large scale attenuation takes place in blue-green region of solar spectrum likely due to aerosol particles injected by industrial advancement over the region. consequent rapid urbanisation and resultant changed land-use patterns. Values show evidences on the role played by moisture field on the transmission characteristics of the Pune skies. The afternoon irradiances are seen to be generally higher than the forenoon values. However, IR and yellow-orange wavelengths have higher irradiances in the forenoons during the pre-monsoon months and occasionally even in March. Over a year 774 Wm-2 of irradiance can be expected on any cloudless occasion around noon time, the individual spectral values vary depending on the actual sky and atmospheric conditions. From the comparative study of the irradiances in the different spectral regions, inferences could be drawn on the changes that take place in the size distribution of aerosol particles during a day.

Author(s):  
Arthur C. Nelsonand ◽  
Thomas W. Sanchez

The rail system operated by the Metropolitan Atlanta Rapid Transit Authority (MARTA) began operating in 1979. As its 20th anniversary nears, how has it influenced land use patterns? Results are mixed. Throughout the Atlanta metropolitan area, the population continues to sprawl outward and MARTA’s facilities do not appear to attract large-scale residential development to them. On the other hand, employment also continues to decentralize, and MARTA’s rail facilities appear to have attracted employment-based development. As MARTA extends service into the affluent northern tier suburbs, its attractiveness to employment centers and perhaps higher-density residential development should improve. The downside is that MARTA is exhausting its reach because most of the region’s new development is outside its jurisdiction.


2011 ◽  
pp. 49-76
Author(s):  
Li Xin ◽  
Karen R. Polenske ◽  
Zhiyu Chen

Since 2000, many cities in China have moved their large-scale manufacturing plants from urban to suburban or other less-developed regions. This inter- or intraregional plant relocation not only leads to changes in land use patterns but also affects institutional, socioeconomic, and environmental issues both at the local and regional levels. We call this regional restructuring process land recycling, which creates critical energy, environmental, financial, social, and political implications. Using Beijing to illustrate the impacts of land recycling, we also discuss the land pollution-related changes and their implications for land and environmental policymaking.


2018 ◽  
Vol 93 (1) ◽  
pp. 48-88
Author(s):  
Lisbeth Prøsch-Danielsen ◽  
Christopher Prescott ◽  
Mads Kähler Holst

Zusammenfassung Basierend auf einer Untersuchung der ökologischen und archäologischen Hinterlassenschaften für Jæren, Südwest-Norwegen, wird vorgeschlagen, dass der Übergang zu einer agrar-pastoralen Wirtschaft und Gesellschaft am Übergang vom mittleren zum späten Neolithikum (2400–2350 v. Chr.) erfolgte und es in Folge zu einer raschen Strukturierung der besiedelten Kulturlandschaften kam. In den folgenden Jahrzehnten und Jahrhunderten entwickelte sich die Gesellschaft auf dieser Basis fort. >Eines der charakteristischen Merkmale der damaligen Landschaften ist, dass diese umfassend in das soziale und rituelle Leben integriert wurden, was auf lokaler Ebene zu einer Zonierung der Landschaft mit jeweils deutlichen Unterschieden in den wirtschaftlichen, sozialen und kulturellen Ausdrucksformen führte. In den offenen, gras- und heidedominierten Küstenzonen manifestiert sich der Befund auf monumentaler und ritueller Ebene, während geeignete quartäre Lagerstätten als Zonen unterschiedlich intensiven Getreideanbaus genutzt wurden. Die beschriebenen Landschaften entwickelten sich als Reaktion auf eine nachhaltige Wirtschaftspraxis, die eine kontinuierliche Ausweitung der Beweidung, eine Intensivierung der Getreideproduktion und den Zugang zu Kommunikationswegen umfasste. Unterschiede im Nutzungsdruck, in der Produktion und in der Wirtschaftsstrategie spiegeln eine Reihe von Umweltparametern wider. Somit korrelieren die Aktivitätszonen weitgehend mit physikalischen Eigenschaften der Landschaft, was offensichtlich sowohl einen adaptiven Aspekt in der Wirtschaft als auch Muster einer umfassenden Ressourcenausnutzung der Zonen widerspiegelt, etwa in der Kombination von Getreideproduktion, Wanderweidewirtschaft, Jagd und Zugang zu maritimen Engstellen. Zur Interpretation schlagen die Autoren ein Modell sozialer und wirtschaftlicher Organisationen und Interaktionen in der Region Jæren vor, basierend auf den Verteilungen mehrerer Kategorien archäologischer Funde. Das Modell präsentiert eine Reihe voneinander abhängiger Zonen innerhalb einer einheitlichen, aber diversifizierten Wirtschaft mit Querschnittsaktivitäten und Mobilitätsmustern. Der präsentierte Ansatz stellt eine Alternative zu bestehenden Hierarchiemodellen innerhalb begrenzter Gebiete dar. Die Landschaftszonierung in Jæren ähnelt jener in Westskandinavien, einschließlich Jütlands, Dänemark. Aus diesem Grund war die Einführung einer subsistenzorientierten, Feldbau und Weidewirtschaft kombinierenden Landwirtschaft in Jæren von externen Impulsen abhängig.


2008 ◽  
Vol 8 (2) ◽  
pp. 4561-4602 ◽  
Author(s):  
L. Hoffmann ◽  
M. Kaufmann ◽  
R. Spang ◽  
R. Müller ◽  
J. J. Remedios ◽  
...  

Abstract. From July 2002 to March 2004 the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) aboard the European Space Agency's Environmental Satellite (Envisat) measured nearly continuously mid infrared limb radiance spectra. These measurements are utilised to retrieve the global distribution of the chlorofluorocarbon CFC-11 by applying a new fast forward model for Envisat MIPAS and an accompanying optimal estimation retrieval processor. A detailed analysis shows that the total retrieval errors of the individual CFC-11 volume mixing ratios are typically below 10% and that the systematic components are dominating. Contribution of a priori information to the retrieval results are less than 5 to 10%. The vertical resolution of the observations is about 3 to 4 km. The data are successfully validated by comparison with several other space experiments, an air-borne in-situ instrument, measurements from ground-based networks, and independent Envisat MIPAS analyses. The retrieval results from 425 000 Envisat MIPAS limb scans are compiled to provide a new climatological data set of CFC-11. The climatology shows significantly lower CFC-11 abundances in the lower stratosphere compared with the Reference Atmospheres for MIPAS (RAMstan V3.1) climatology. Depending on the atmospheric conditions the differences between the climatologies are up to 30 to 110 ppt (45 to 150%) at 19 to 27 km altitude. Additionally, time series of CFC-11 mean abundance and variability for five latitudinal bands are presented. The observed CFC-11 distributions can be explained by the residual mean circulation and large-scale eddy-transports in the upper troposphere and lower stratosphere. The new CFC-11 data set is well suited for further scientific studies.


2021 ◽  
Vol 14 (1) ◽  
pp. 25-47
Author(s):  
Stephane Castonguay ◽  
Hubert Samson

This essay focuses on the processes of territorialization, deterritorialization and reterritorialization through which Euro-Canadian society extended its control along the valley of the St. Maurice River between 1850 and 1930. That territory had been settled by the Atikamekw people where they had established their hunting and fishing grounds for centuries. However, the Atikamekw people were confronted by environmental and technological transformations around the St. Maurice River with the implementation of sociotechnical systems during that time period, as two successive phases of industrialization based on specific water use brought along a proliferation of urban centers and the arrival of the large-scale industry. This was particularly the case when the proliferation of hydroelectric dams along the St. Maurice River and its tributaries followed the construction of fluvial infrastructure to facilitate the floating of wood pulp harvested in the upper basin of the river. Not only did the technical activities surrounding the construction of hydroelectric facilities materially transform the St. Maurice River watershed, they also allowed a symbolic appropriation of the land by the production of maps and surveys that ‘erased’ the presence of the Atikamekw. Physical and symbolic boundaries resulting from these new forms of organization and configuration of the territory restricted the spatial practices and representations of the Atikamekw. Logging confined these people within isolated enclaves (the so-called “Indian reserves”), while dams bypassed their networks of exchange and communication. The aim of this essay is to understand the conflicts between the territorialities of the Atikamekw and that of the Euro-Canadians by focusing on the place of water uses within the geographical imaginations and the land use patterns of these populations.


Atmosphere ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1198
Author(s):  
Mourad Benlattar ◽  
Issam Ibourk ◽  
Rahma Adhiri

The passive radiative cooling approach refers to the physical process that pumps heat into outer space via the atmospheric window (8–13 μm) without energy input. The ability to continuously adjust the emissivity of thermal emitters in the sky window while maintaining high reflectivity in the solar spectrum remains a challenge. In order to achieve this task, a novel design referred to as double-layer nanoparticle-based coating is proposed. Our proposed emitter is appropriate for both high solar reflection and strong mid-infrared emissivity. The bottom and top layers are Al2O3 embedded with Ni nanoparticles and a super-hydrophilic TiO2-SiO2 layer. The bottom layer is designed to achieve high emissivity in “the atmospheric transparency window”. The top layer is designed to block solar illumination and to favor an enhanced cleanability of the coated design. Our double-layer coating as an optical solar reflector has excellent solar irradiation ( and is strongly emissive (0.97) across the “full sky window” at room temperature. Furthermore, a detailed numerical energy study has been performed, evaluating the temperature reduction and the radiative cooling performance under different conditions. The proposed simple coating can be used as an efficient radiative cooler on a large scale for energy conservation and thermoelectric devices.


1973 ◽  
Vol 33 (1) ◽  
pp. 274-290 ◽  
Author(s):  
Philip M. Raup

Corporate farming is not new in the United States. The companies of “gentlemen adventurers” setting out in the seventeenth century to establish settlements in the New World were not corporations in a modern sense, but in organizational form and motivation they bear a striking resemblance to corporation farming ventures of recent decades. The twin lures of short-run profits and long-run capital gains have been major forces in shaping land use patterns and institutional structures throughout America's history. For over 300 years repeated efforts were made to use large scale organizational forms to reap these rewards in agriculture. Up to 1950 the record was one of almost consistent failure.


2000 ◽  
Vol 7 (1) ◽  
pp. 43 ◽  
Author(s):  
Robert M. Emanuel ◽  
James B. Greenberg

This paper outlines the major factors contributing to deforestation in the Sierra Chatina of Oaxaca, Mexico and examines the role played by neo-liberal restructuring in these processes. The last 25 years of rural development in the Sierra Chatino has been accompanied by increasingly large-scale environmental changes.  The most obvious outcome has been the loss of 40 percent of the areas natural vegetation. Deforestation has accelerated and exacerbated flooding and climate changes in the region as witnessed by the effects of El Niño driven storms such as Hurricane Pauline. This paper will focus on these processes of deforestation in the region. In this paper, we argue that the Mexican government’s neo-liberal policies have encouraged the commoditization of the Sierra Chatina forests at the expense of long-term ecological sustainability. Since 1992, Mexico has moved toward privatization of forests by removing the legal roadblocks to leasing of ejido and communal lands. Moreover, as neo-liberal policies have devalued the currency, eliminated subsidies, the Chatino have been pushed deeper into poverty, and into unsustainable uses of their forests. Thus, we contend that transformations of land-use patterns seen in these coastal mountains are part of a fundamental shift in local livelihoods from subsistence to cash-based strategies. Keywords: deforestation, Mexico, Oaxaca, Chatino, neo-liberal policy, ecological sustainablity, migration, political ecology, el Niño, privatization, climate change, environmental degradation, rural development.


The Holocene ◽  
2018 ◽  
Vol 28 (12) ◽  
pp. 1979-1991
Author(s):  
Youngrong Moon ◽  
Hong-Jong Lee ◽  
Heejin Lee

Large-scale excavations between 2012 and 2015 at the Daepyeongri site on the floodplain of the River Geumgang have revealed the presence of an ancient complex settlement comprising houses, extensive agricultural fields, and pits that have been dated to between the Bronze Age and the early Three Kingdoms periods. The beginning and end of the occupation of this site and land-use patterns are assumed to have been associated with its natural environment. The pollen records presented in this study show that wet conditions continued throughout the time that this site was occupied, evidenced by the consistent appearance of Alnus, while there are nevertheless hints of some land reclamation from the Bronze Age onwards. More intensive agricultural activities that took place during this later period are evidenced by an increase in the abundance of NAP pollens related to cultivation including Gramineae, Cyperaceae, Bistorta, Compositae and Fagopyrum. At the end of the occupation period, an abrupt transition to wetter conditions is recognized while dry land condition had been prevalent for some time in other parts of the site. Microscopic examination of buried cultivated soils that evidence multiple phases of ancient field systems has enabled the identification of pedological traces of discrete cultivation patterns and shows that they changed over time. The recognition of micro-structures and associated features shows that seasonally flooded wetland was first utilized during the early phase (the Bronze Age), and that more intensified irrigation management was seen during the late phase (the time span encompassed by the proto-Kingdoms and Three Kingdoms periods). These data reveal evidence for intensive hydromorphic degradation and enable a robust recognition of settlement history and an enhanced understanding of the intensity of various land-use patterns, and landscape changes from both environmental and archaeological perspectives.


2020 ◽  
Vol 9 (9) ◽  
pp. 524
Author(s):  
Jianming Liang ◽  
Jianhua Gong ◽  
Xiuping Xie ◽  
Jun Sun

Solar3D is an open-source software application designed to interactively calculate solar irradiation on three-dimensional (3D) surfaces in a virtual environment constructed with combinations of 3D-city models, digital elevation models (DEMs), digital surface models (DSMs) and feature layers. The GRASS GIS r.sun solar radiation model computes solar irradiation based on two-dimensional (2D) raster maps for a given day, latitude, surface and atmospheric conditions. With the increasing availability of 3D-city models and demand for solar energy, there is an urgent need for better tools to computes solar radiation directly with 3D-city models. Solar3D extends the GRASS GIS r.sun model from 2D to 3D by feeding the model with input, including surface slope, aspect and time-resolved shading, which is derived directly from the 3D scene using computer graphics techniques. To summarize, Solar3D offers several new features that—as a whole—distinguish this novel approach from existing 3D solar irradiation tools in the following ways. (1) Solar3D can consume massive heterogeneous 3D-city models, including massive 3D-city models such as oblique airborne photogrammetry-based 3D-city models (OAP3Ds or integrated meshes); (2) Solar3D can perform near real-time pointwise calculation for duration from daily to annual; (3) Solar3D can integrate and interactively explore large-scale heterogeneous geospatial data; (4) Solar3D can calculate solar irradiation at arbitrary surface positions including on rooftops, facades and the ground.


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