scholarly journals Regional-Scale Rainy Season Onset Detection: A New Approach Based on Multivariate Analysis

2013 ◽  
Vol 26 (22) ◽  
pp. 8916-8928 ◽  
Author(s):  
Joseph Boyard-Micheau ◽  
Pierre Camberlin ◽  
Nathalie Philippon ◽  
Vincent Moron

Abstract In agroclimatology, the rainy season onset and cessation dates are often defined from a combination of several empirical rainfall thresholds. For example, the onset may be the first wet day of N consecutive days receiving at least P millimeters without a dry spell lasting n days and receiving less than p millimeters in the following C days. These thresholds are parameterized empirically in order to fit the requirements of a given crop and to account for local-scale climatic conditions. Such local-scale agroclimatic definition is rigid because each threshold may not be necessarily transposable to other crops and other climate environments. A new approach is developed to define onset/cessation dates and monitor their interannual variability at the regional scale. This new approach is less sensitive to parameterization and local-scale contingencies but still has some significance at the local scale. The approach considers multiple combinations of rainfall thresholds in a principal component analysis so that a robust signal across space and parameters is extracted. The regional-scale onset/cessation date is unequally influenced by input rainfall parameters used for the definition of the local rainy season onset. It appears that P is a crucial parameter to define onset, C plays a significant role at most stations, and N seems to be of marginal influence.

2020 ◽  
Vol 164 ◽  
pp. 07028
Author(s):  
Anastasia Vasilieva ◽  
Raisa Belaya

Significant heterogeneity of the level of development of the Russian border, including in the field of recreation, imposes requirements for differentiation in the regional policy. Definition of the types of territories helps to solve applied management tasks more effectively. In this context, the factors by which these types were formed are important. To solve this problem, the authors conducted a factor analysis through the principal component method using oblique factor rotation. Three blocks of variables were analyzed that characterize the subjects of the Russian Federation that have land borders on the mainland (including river and lake borders) and sea borders with neighboring countries located on the map clockwise from Norway to the United States (border regions of Russia) for the period from 2010 to 2018. As a result, five factors were identified: the factor of the demand for the services of the recreational system, the factor of the development of the infrastructure of the recreational system in climatic conditions, the environmental safety factor, the factor of investment in the development of the recreational system infrastructure, the factor of the location at the border. The results of the study can be used as a practical tool for developing recommendations in the field of regional policy aimed at development of a recreational system, taking into account the factors determined for each identified group. The results of the study were obtained in the framework of the state task of the IE KarRC RAS on the topic “Institutions and social inequality in the face of global challenges and regional restrictions”.


Author(s):  
Pan Bi ◽  
Lixin Pei ◽  
Guanxing Huang ◽  
Dongya Han ◽  
Jiangmin Song

Efficient identification of groundwater contamination is a major issue in the context of groundwater use and protection. This study used a new approach of multi-hydrochemical indicators, including the Cl-Br mass ratio, the hydrochemical facies, and the concentrations of nitrate, phosphate, organic contaminants, and Pb in groundwater to identify groundwater contamination in the Pearl River Delta (PRD) where there is large scale urbanization. In addition, the main factors resulting in groundwater contamination in the PRD were also discussed by using socioeconomic data and principal component analysis. Approximately 60% of groundwater sites in the PRD were identified to be contaminated according to the above six indicators. Contaminated groundwaters commonly occur in porous and fissured aquifers but rarely in karst aquifers. Groundwater contamination in porous aquifers is positively correlated with the urbanization level. Similarly, in fissured aquifers, the proportions of contaminated groundwater in urbanized and peri-urban areas were approximately two times that in non-urbanized areas. Groundwater contamination in the PRD was mainly attributed to the infiltration of wastewater from township-village enterprises on a regional scale. In addition, livestock waste was also an important source of groundwater contamination in the PRD. Therefore, in the future, the supervision of the wastewater discharge of township-village enterprises and the waste discharge of livestock should be strengthened to protect against groundwater contamination in the PRD.


2006 ◽  
Vol 49 (6) ◽  
pp. 935-944 ◽  
Author(s):  
Flavio Nunes Ramos ◽  
Flavio Antonio Maës Santos

The aim of this work was to investigate whether (i) the organisms within different fragments, on regional scale (separated by up to 100 km), could be submitted to similar climatic conditions (rainfall and temperature), and whether (ii) the edge formation in forest fragments could stimulate microclimatic changes (canopy cover, air temperature and soil humidity), on local scale. The organisms within different fragments, on regional scale, were submitted to different climatic conditions, and the edge formation in the forest fragment stimulated microclimatic changes, on local scale, although in a heterogenic way. Not just the distance from the edge influenced the microclimatic differences. Probably, the edge age, location, the matrix structure, as well as, gap proximity could change the microclimatic even within edges.


2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Anandi Silva Knuppel

Scholarship on Hindu traditions and practices proposes the practice of darshan as fundamental to Hindu traditions, particularly in temple worship, observing that devotees seek out images of deities primarily to see them and “receive” their darshan. These works typically gloss the definition of darshan with a sentence or two about seeing, exchanging glances, and/or receiving blessings. In this paper, I focus on the ways in which darshan is ideally imagined in conjunction with other bodily sensory practices through sources of authority, such as texts and senior devotees, to create a specific sensory experience and expectation in the transnational Gaudiya Vaishnava community. I then look to the lived realitiesof darshan in this tradition, specifically how devotees negotiate the structures created through sources of authority in their daily lives. Through this juxtaposition of idealized and lived darshan, I argue that we need a new approach towards theories of practice to take into account the complexities of darshanic moments in this and other religious practices.


2018 ◽  
Vol 28 (2) ◽  
pp. 483-487
Author(s):  
Snezhina Georgieva ◽  
Dilyana Zvezdova

Psoriatic arthritis is an inflammatory joint disease associated with psoriasis vulgaris, with routinely negative rheumatoid factors and the absence of rheumatoid nodules. This is an immune-mediated disease, according to generally accepted definition of Wright and Moll from 1973. American Association against Rheumatism classified psoriatic arthritis as an independent disease in 1964. Psoriatic arthritis is a single disease with a varied clinical picture. It belongs to the group of seronegative spondyloarthropathies with which there are general clinical features. It is believed that similar mechanisms determine the onset of psoriasis and psoriatic arthritis. The clinical picture includes various clinical forms that damage the peripheral and sacroiliac joints, spine, internal organs. The treatment of psoriatic arthritis is directed simultaneously to the influence of skin and joint changes. Purpose: Our study aims to summarize our long-standing experience in the treatment of psoriatic arthritis with heliotherapy. Subject of observation: Monitoring includes 132 patients with moderate and severe form of psoriasis treated at the sanatorium in town of Pomorie for 5 years in the period 2001-2006. Results and discussion: 132 patients with psoriasis with no effect on the local therapy and have proven psoriatic arthritis were selected. In our climatic conditions, heliotherapy is appointed during the warm half-year. Sun treatment was conducted under the conditions of a healing beach, which had shielding, radiation-protective devices. In patients with erythema - pigment and pigment type skin reactivity begins with 1-2 bioadoses reached to 8-10 biodoses, carried out in the area of overcomfort. Conclusion: The studies demonstrated that heliotherapy combined with medications significantly improves the prognosis of patients with this disease. The ultimate success would mean overcoming the frequent depression conditions, better survival and social comfort for patients with psoriatic arthritis.


Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 334
Author(s):  
Norbert Szymański ◽  
Sławomir Wilczyński

The present study identified the similarities and differences in the radial growth responses of 20 provenances of 51-year-old European larch (Larix decidua Mill.) trees from Poland to the climatic conditions at three provenance trials situated in the Polish lowlands (Siemianice), uplands (Bliżyn) and mountains (Krynica). A chronology of radial growth indices was developed for each of 60 European larch populations, which highlighted the interannual variations in the climate-mediated radial growth of their trees. With the aid of principal component, correlation and multiple regression analysis, supra-regional climatic elements were identified to which all the larch provenances reacted similarly at all three provenance trials. They increased the radial growth in years with a short, warm and precipitation-rich winter; a cool and humid summer and when high precipitation in late autumn of the previous year was noted. Moreover, other climatic elements were identified to which two groups of the larch provenances reacted differently at each provenance trial. In the lowland climate, the provenances reacted differently to temperature in November to December of the previous year and July and to precipitation in September. In the upland climate, the provenances differed in growth sensitivity to precipitation in October of the previous year and June–September. In the mountain climate, the provenances responded differently to temperature and precipitation in September of the previous year and to precipitation in February, June and September of the year of tree ring formation. The results imply that both climatic factors and origin (genotype), i.e., the genetic factor, mediate the climate–growth relationships of larch provenances.


Atmosphere ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 12
Author(s):  
Yulia Ivanova ◽  
Anton Kovalev ◽  
Vlad Soukhovolsky

The paper considers a new approach to modeling the relationship between the increase in woody phytomass in the pine forest and satellite-derived Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) (MODIS/AQUA) data. The developed model combines the phenological and forest growth processes. For the analysis, NDVI and LST (MODIS) satellite data were used together with the measurements of tree-ring widths (TRW). NDVI data contain features of each growing season. The models include parameters of parabolic approximation of NDVI and LST time series transformed using principal component analysis. The study shows that the current rate of TRW is determined by the total values of principal components of the satellite indices over the season and the rate of tree increment in the preceding year.


Author(s):  
Siqi Sun ◽  
Yihe Lü ◽  
Da Lü ◽  
Cong Wang

Forests are critical ecosystems for environmental regulation and ecological security maintenance, especially at high altitudes that exhibit sensitivity to climate change and human activities. The Qinghai-Tibet Plateau—the world’s largest water tower region—has been breeding many large rivers in Asia where forests play important roles in water regulation and water quality improvement. However, the vulnerability of these forest ecosystems at the regional scale is still largely unknown. Therefore, the aim of this research is to quantitatively assess the temporal–spatial variability of forest vulnerability on the Qinghai-Tibet Plateau to illustrate the capacity of forests to withstand disturbances. Geographic information system (GIS) and the spatial principal component analysis (SPCA) were used to develop a forest vulnerable index (FVI) to assess the vulnerability of forest ecosystems. This research incorporates 15 factors covering the natural context, environmental disturbances, and socioeconomic impact. Results indicate that the measure of vulnerability was unevenly distributed spatially across the study area, and the whole trend has intensified since 2000. The three factors that contribute the most to the vulnerability of natural contexts, environmental disturbances, and human impacts are slope aspect, landslides, and the distance to the farmland, respectively. The vulnerability is higher in forest areas with lower altitudes, steeper slopes, and southerly directions. These evaluation results can be helpful for forest management in high altitude water tower regions in the forms of forest conservation or restoration planning and implementation towards sustainable development goals.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xu Zhang ◽  
Hoang Nguyen ◽  
Jeffrey T. Paci ◽  
Subramanian K. R. S. Sankaranarayanan ◽  
Jose L. Mendoza-Cortes ◽  
...  

AbstractThis investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways. It incorporates a multi-objective genetic algorithm, training and screening property sets, and correlation and principal component analyses. The framework enables iterative definition of properties in the training and screening sets, guided by correlation relationships between properties, aiming to achieve optimal parametrizations for properties of interest. Specifically, the performance of increasingly complex potentials, Buckingham, Stillinger-Weber, Tersoff, and modified reactive empirical bond-order potentials are compared. Using MoSe2 as a case study, we demonstrate good reproducibility of training/screening properties and superior transferability. For MoSe2, the best performance is achieved using the Tersoff potential, which is ascribed to its apparent higher flexibility embedded in its functional form. These results should facilitate the selection and parametrization of interatomic potentials for exploring mechanical and phononic properties of a large library of two-dimensional and bulk materials.


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