scholarly journals A HOMOGENEOUS EARTHQUAKE CATALOG OF INTERMEDIATE-DEEP FOCUS GLOBAL SEISMICITY: COMPLETENESS AND SPATIO-TEMPORAL ANALYSIS

2017 ◽  
Vol 50 (3) ◽  
pp. 1270
Author(s):  
A.D. Tsampas ◽  
E.M. Scordilis ◽  
C.B. Papazachos ◽  
G.F. Karakaisis
Keyword(s):  
Large Scale ◽  
Spatiotemporal Analysis ◽  
Temporal Analysis ◽  
Mean Value ◽  
Earthquake Catalog ◽  
Intermediate Depth ◽  
Spatio Temporal ◽  
Global Seismicity ◽  
Deep Focus ◽  
The Moment

homogeneous with respect to magnitude earthquake catalog is compiled, particularly focusing on the global intermediate depth-deep focus seismicity and by exploiting data of almost half-century. Within a two-step compilation process, we take advantage of 10 robust conversion equations produced exclusively for intermediate depth and deep focal data (Tsampas et al., 2016). Initially, magnitudes of different scales and several origins are converted into proxy moment magnitudes (Mw*~Mw) and a weighted mean-value aggregation procedure is then applied for all events with estimated Mw*. Therefore, a homogeneous magnitude scale (equivalent to Mw) is obtained as result of individual correlations between different magnitude scales and the moment magnitude (Mw) scale, yielding a unique magnitude value per event. Moreover, through implementing a simple optimization scheme, a composed, unique depth value per event is estimated, utilizing focal data from multiple resources. In the end and after validating magnitude’s (M) reliability, a brief spatiotemporal analysis of the provided catalog is performed, revealing its potential for further exploitation in large scale seismological surveys or other research studies of global interest.

scholarly journals Spatio-temporal dynamics of dengue in Brazil: seasonal travelling waves and determinants of regional synchrony

2018 ◽  
Author(s):  
Mikhail Churakov ◽  
Christian J. Villabona-Arenas ◽  
Moritz U.G. Kraemer ◽  
Henrik Salje ◽  
Simon Cauchemez
Keyword(s):  
Large Scale ◽  
Temporal Dynamics ◽  
Mosquito Control ◽  
Human Mobility ◽  
Travelling Waves ◽  
Seasonal Pattern ◽  
Temporal Analysis ◽  
Vector Ecology ◽  
Spatio Temporal ◽  
Dengue Epidemics

AbstractDengue continues to be the most important vector-borne viral disease globally and in Brazil, where more than 1.4 million cases and over 500 deaths were reported in 2016. Mosquito control programmes and other interventions have not stopped the alarming trend of increasingly large epidemics in the past few years.Here, we analyzed monthly dengue cases reported in Brazil between 2001 and 2016 to better characterize the key drivers of dengue epidemics. Spatio-temporal analysis revealed recurring travelling waves of disease occurrence. Using wavelet methods, we characterised the average seasonal pattern of dengue in Brazil, which starts in the western states of Acre and Rondônia, then travels eastward to the coast before reaching the northeast of the country. Only two states in the north of Brazil (Roraima and Amapá) did not follow the countrywide pattern and had inconsistent timing of dengue epidemics throughout the study period.We also explored epidemic synchrony and timing of annual dengue cycles in Brazilian regions. Using gravity style models combined with climate factors, we showed that both human mobility and vector ecology contribute to spatial patterns of dengue occurrence.This study offers a characterization of the spatial dynamics of dengue in Brazil and its drivers, which could inform intervention strategies against dengue and other arboviruses.Author summaryIn this paper we studied the synchronization of dengue epidemics in Brazilian regions. We found that a typical dengue season in Brazil can be described as a wave travelling from the western part of the country towards the east, with the exception of the two most northern equatorial states that experienced inconsistent seasonality of dengue epidemics.We found that the spatial structure of dengue cases is driven by both climate and human mobility patterns. In particular, precipitation was the most important factor for the seasonality of dengue at finer spatial resolutions.Our findings increase our understanding of large scale dengue patterns and could be used to enhance national control programs against dengue and other arboviruses.

scholarly journals (Im-)material flow analysis framework implementation on repair and reuse initiatives

2020 ◽  
Vol 108 (5-6) ◽  
pp. 509 ◽  
Author(s):  
Julie Gobert ◽  
Romain Allais
Keyword(s):  
Material Flow ◽  
Flow Analysis ◽  
Material Flow Analysis ◽  
Spatiotemporal Analysis ◽  
Temporal Analysis ◽  
Local Initiatives ◽  
Spatio Temporal ◽  
Stakeholder Network ◽  
Multi Scales

This research aims at understanding better the nature of stakeholders’ resistance to and interest in repair and reuse. In fact, the authors assume that in the future waste management could be less centralized using a network of territorialized initiatives based on repair and reuse activities with high social and environmental values. Such system innovation requires tools and methods to support analysis and facilitate decision-making in multi-stakeholders, multi-scales systems. The framework for spatiotemporal analysis of territorial projects considers a project’s stakeholder network and the way they mobilize resources. These resources may be tangible or intangible, brought by individuals, organizations or even the territory. This communication focuses on the implementation of such an analysis in the community of communes Coeur de Savoie, to understand how local initiatives emerge and on which interactions and resources they are based. This paper proposes feedback on the implementation of the spatio-temporal analysis in one case study (Coeur de Savoie), and provides insights to build new networks promoting reuse and repair.

scholarly journals SPATIO-TEMPORAL DYNAMIC OF LAND DEGRADATION USING REMOTE SENSING-BASED INDEX

AGROFOR ◽  
2021 ◽  
Vol 4 (2) ◽  
Author(s):  
Seyed Hamidreza SADEGHI ◽  
Fahimeh MIRCHOOLI ◽  
Abdulvahed KHALEDI DARVISHAN
Keyword(s):  
Remote Sensing ◽  
Land Degradation ◽  
Net Primary Productivity ◽  
Temporal Analysis ◽  
Mean Value ◽  
Annual Rainfall ◽  
Landsat Images ◽  
Policy Makers ◽  
Use Efficiency ◽  
Spatio Temporal

Land degradation is the major issue which affect watershed sustainability and following social, economic and environmental of livelihood people. So, early detection of land degradation is necessary for policy-makers to make appropriate decision. In this way, remote sensing method is a candidate choice for assessments and monitoring. In this study, land degradation was assessed using Rain-Use Efficiency (RUE) in the Shazand Watershed, Iran in 1986, 1998, 2008 and 2016. Thus, annual rainfall was calculated using inverse distance weight (IDW), net primary productivity (NPP) were calculated using Landsat images. The results indicated that RUE had increasing and then decreasing trends which were 10.66, 33.77, 20.03 and 9.47 kg C ha-1 yr-1. The results also illustrate that the mean value of RUE in different land uses varied between the irrigated land and orchard that had the highest value and outcrop dominant areas and bareland had the lowest value of RUE among land use categories. It is also established that spatio-temporal analysis of RUE can provide valuable information about the trend of watershed’s sustainability over years.

scholarly journals AN EARTHQUAKE CATALOG OF MID-ATLANTIC RIDGE

2017 ◽  
Vol 50 (3) ◽  
pp. 1258 ◽  
Author(s):  
E. Teza ◽  
E.M. Scordilis ◽  
C.B. Papazachos ◽  
G.F. Karakaisis
Keyword(s):  
Large Scale ◽  
Time Window ◽  
Magnitude Scale ◽  
Earthquake Catalog ◽  
Strong Earthquakes ◽  
Completeness Magnitude ◽  
Mid Atlantic Ridge ◽  
The Moment ◽  
Definition Of ◽  
Reference Agency

The Mid-Atlantic Ridge (M-AR), which runs along the centre of the Atlantic Ocean, is one of the best known divergent boundaries. Seismic studies have been a crucial factor in deciphering the structure of the oceanic crust. For their performance a necessary prerequisite is the compilation of a reliable earthquake catalog of the broader area. In this study, an attempt was made to create an earthquake catalog of M-AR that could become a useful “tool” for large-scale seismological studies of this region. For this reason a very large sample of data from several seismological centers, as well as from already published catalogs of strong earthquakes, was collected and examined. ISC was considered as the main reference agency, while as reference magnitude scale the moment magnitude scale, MW was adopted. The main goal was to identify and organize the best and most recent information available for earthquakes falling within the time window 1900-2014 and the space window bounded by the extended coordinates ~ 81 (N) to -51 (S) and 10 (E) to ~ -50 (W). After magnitude homogenization, check of focal depths and definition of completeness magnitude, a reliable and homogeneous earthquake catalog of M AR consisting of 14,211 events was created, available for any seismological use and further study.

scholarly journals Flood-initiating catchment conditions: a spatio-temporal analysis of large-scale soil moisture patterns in the Elbe River basin

2013 ◽  
Vol 17 (4) ◽  
pp. 1401-1414 ◽  
Author(s):  
M. Nied ◽  
Y. Hundecha ◽  
B. Merz
Keyword(s):  
Soil Moisture ◽  
River Basin ◽  
Large Scale ◽  
Principal Component ◽  
Temporal Analysis ◽  
Elbe River ◽  
High Soil Moisture ◽  
Elbe River Basin ◽  
Spatio Temporal ◽  
The Elbe River

Abstract. Floods are the result of a complex interaction between meteorological event characteristics and pre-event catchment conditions. While the large-scale meteorological conditions have been classified and successfully linked to floods, this is lacking for the large-scale pre-event catchment conditions. Therefore, we propose classifying soil moisture as a key variable of pre-event catchment conditions and investigating the link between soil moisture patterns and flood occurrence in the Elbe River basin. Soil moisture is simulated using a semi-distributed conceptual rainfall-runoff model over the period 1951–2003. Principal component analysis (PCA) and cluster analysis are applied successively to identify days of similar soil moisture patterns. The results show that PCA considerably reduced the dimensionality of the soil moisture data. The first principal component (PC) explains 75.71% of the soil moisture variability and represents the large-scale seasonal wetting and drying. The successive PCs express spatially heterogeneous catchment processes. By clustering the leading PCs, we identify large-scale soil moisture patterns which frequently occur before the onset of floods. In winter, floods are initiated by overall high soil moisture content, whereas in summer the flood-initiating soil moisture patterns are diverse and less stable in time.

scholarly journals On the spatio-temporal analysis of hydrological droughts from global hydrological models

2011 ◽  
Vol 8 (1) ◽  
pp. 619-652 ◽  
Author(s):  
G. A. Corzo Perez ◽  
M. H. J. van Huijgevoort ◽  
F. Voß ◽  
H. A. J. van Lanen
Keyword(s):  
Time Series ◽  
20Th Century ◽  
Large Scale ◽  
Southern Oscillation ◽  
Regional Scale ◽  
Spatial Coherence ◽  
Temporal Analysis ◽  
Global Scale ◽  
Scale Models ◽  
Spatio Temporal

Abstract. The recent concerns for world-wide extreme events related to climate change phenomena have motivated the development of large scale models that simulate the global water cycle. In this context, analyses of extremes is an important topic that requires the adaptation of methods used for river basin and regional scale models. This paper presents two methodologies that extend the tools to analyze spatio-temporal drought development and characteristics using large scale gridded time series of hydrometeorological data. The methodologies are distinguished and defined as non-contiguous and contiguous drought area analyses (i.e. NCDA and CDA). The NCDA presents time series of percentages of areas in drought at the global scale and for pre-defined regions of known hydroclimatology. The CDA is introduced as a complementary method that generates information on the spatial coherence of drought events at the global scale. Spatial drought events are found through CDA by clustering patterns (contiguous areas). In this study the global hydrological model WaterGAP was used to illustrate the methodology development. Global gridded time series (resolution 0.5°) simulated with the WaterGAP model from land points were used. The NCDA and CDA were applied to identify drought events in subsurface runoff. The percentages of area in drought calculated with both methods show complementary information on the spatial and temporal events for the last decades of the 20th century. The NCDA provides relevant information on the average number of droughts, duration and severity (deficit volume) for pre-defined regions (globe, 2 selected climate regions). Additionally, the CDA provides information on the number of spatially linked areas in drought as well as their geographic location on the globe. An explorative validation process shows that the NCDA results capture the overall spatio-temporal drought extremes over the last decades of the 20th century. Events like the El Niño Southern Oscillation (ENSO) in South America and the pan-European drought in 1976 appeared clearly in both analyses. The methodologies introduced provide an important basis for the global characterization of droughts, model inter-comparison, and spatial events validation.

scholarly journals Dynamics of monthly amount of rainfall in the territory of Kharkiv region

2019 ◽  
Keyword(s):  
Large Scale ◽  
Precipitation Amount ◽  
Atmospheric Precipitation ◽  
Temporal Analysis ◽  
Monthly Rainfall ◽  
Moisture Regime ◽  
Monthly Precipitation ◽  
Air Temperatures ◽  
Spatio Temporal ◽  
Calculated Average

The purpose of this article is the spatio-temporal analysis of the monthly rainfall in the territory of Kharkiv region during the year. To determine the dynamics of the territory humidity y, the time series of the monthly amount of precipitation at ten meteorological stations of the oblast were used for two periods: 1961-1990 and 1961-2016. Using statistical methods, features of the monthly precipitation amount distribution for twelve months were determined. The main material. Modern climatic changes, expressed in high air temperatures, are crucial for the formation of moisture within the country or region. Humidification regime is formed under the influence of both large-scale atmospheric processes and physical and geographical factors of the investigated area: landscape, presence of water objects, vegetation cover. The value of the monthly rainfall in winter indicates that in the decade of 1961-1970 it was characterized by an increase of up to 13 mm at all stations in the region. During the next decades arid conditions were observed at the rest of meteorological stations. Significant decrease in the amount of precipitation was observed in the period between 1991-2000at the station Velykyi Burluk (13 mm). In the spring period, there is a general trend towards a slight increase in the amount of precipitation. The value of monthly rainfall in the summer and autumn has a tendency to growth. The analysis of the calculated average parameters and the probability of atmospheric precipitation have showed that changes in the amount of precipitation in the region are characterized by high temporal variability. The change in rainfall is volatile in 2-3 years. Conclusions and further research. By comparing the data for two periods (1961-1990, 1961-2016), the peculiarities of changes in the amount of precipitation during the second half of the last century and the beginning of this century were revealed in the region. It has been established that the precipitation is characterized by high variability over the territory, which is reflected in the humidification regime. In general, there is a tendency to a decrease in the amount of precipitation in November-March periods. The spatial-temporal changes in the amount of atmospheric precipitation in the territory of Kharkiv region by seasons have been revealed: their changes at stations have the greatest amplitudes in winter; maximum values are fixed in the summer. The unstable moisture regime remains in the spring and autumn.

scholarly journals Spatio-Temporal Evolution of Intermediate-Depth Seismicity Beneath the Himalayas: Implications for Metamorphism and Tectonics

2021 ◽  
Vol 9 ◽  
Author(s):  
Konstantinos Michailos ◽  
N. Seth Carpenter ◽  
György Hetényi
Keyword(s):  
Fault Zone ◽  
Earthquake Catalog ◽  
Waveform Data ◽  
Central Himalayas ◽  
Intermediate Depth ◽  
Migration Rates ◽  
Spatio Temporal ◽  
Tear Fault ◽  
Dehydration Processes ◽  
The Himalaya

Intermediate-depth earthquakes (>40 km) have been observed beneath the central Himalayas over decades, with little known about their nature and characteristics. Here, we apply a state-of-the-art systematic processing routine, starting from continuous waveform data, to obtain the most comprehensive high-quality earthquake catalog with a focus on the intermediate-depth seismicity beneath the central Himalayas. We construct a catalog containing 414 robust earthquake locations with depths ranging from 40 to 110 km spanning from late 2001 till mid-2003. We calculate earthquake magnitudes in a consistent way and obtain values ranging between ML 0.8 and 4.5 with a magnitude of completeness of Mc 2.4. This information allows us to study the spatiotemporal characteristics of the seismicity in great detail. Earthquakes mainly take place in a cluster, consisting of two linear segments at ca. 35° azimuth difference, situated beneath the high Himalayas in NE Nepal and adjacent S. Tibet. Seismicity there does not feature any mainshock-aftershock patterns but presents a few sequences with potential seismicity migration rates compatible with linear or diffusive migration. This result, along with previous studies in the lower Indian crust, allows interpreting these events as related to metamorphic reactions involving dehydration processes. However, given the geodynamic context, a tectonic interpretation with a dextral basement fault zone propagating beneath the Himalaya and continuing as a westward propagating tear fault would also be possible. This represents a continuous fault zone from the deep crust in S. Tibet, across the Himalaya along the Dhubri-Chungthang fault zone (DCFZ) to the Shillong plateau, which could be an inherited tectonic feature.

scholarly journals On the spatio-temporal analysis of hydrological droughts from global hydrological models

2011 ◽  
Vol 15 (9) ◽  
pp. 2963-2978 ◽  
Author(s):  
G. A. Corzo Perez ◽  
M. H. J. van Huijgevoort ◽  
F. Voß ◽  
H. A. J. van Lanen
Keyword(s):  
Time Series ◽  
20Th Century ◽  
Large Scale ◽  
Southern Oscillation ◽  
Spatial Coherence ◽  
Temporal Analysis ◽  
Global Scale ◽  
Hydrological Models ◽  
Context Analysis ◽  
Spatio Temporal

Abstract. The recent concerns for world-wide extreme events related to climate change have motivated the development of large scale models that simulate the global water cycle. In this context, analysis of hydrological extremes is important and requires the adaptation of identification methods used for river basin models. This paper presents two methodologies that extend the tools to analyze spatio-temporal drought development and characteristics using large scale gridded time series of hydrometeorological data. The methodologies are classified as non-contiguous and contiguous drought area analyses (i.e. NCDA and CDA). The NCDA presents time series of percentages of areas in drought at the global scale and for pre-defined regions of known hydroclimatology. The CDA is introduced as a complementary method that generates information on the spatial coherence of drought events at the global scale. Spatial drought events are found through CDA by clustering patterns (contiguous areas). In this study the global hydrological model WaterGAP was used to illustrate the methodology development. Global gridded time series of subsurface runoff (resolution 0.5°) simulated with the WaterGAP model from land points were used. The NCDA and CDA were developed to identify drought events in runoff. The percentages of area in drought calculated with both methods show complementary information on the spatial and temporal events for the last decades of the 20th century. The NCDA provides relevant information on the average number of droughts, duration and severity (deficit volume) for pre-defined regions (globe, 2 selected hydroclimatic regions). Additionally, the CDA provides information on the number of spatially linked areas in drought, maximum spatial event and their geographic location on the globe. Some results capture the overall spatio-temporal drought extremes over the last decades of the 20th century. Events like the El Niño Southern Oscillation (ENSO) in South America and the pan-European drought in 1976 appeared clearly in both analyses. The methodologies introduced provide an important basis for the global characterization of droughts, model inter-comparison of drought identified from global hydrological models and spatial event analyses.

scholarly journals Fire and forage quality: post-fire regrowth quality and pyric herbivory in subtropical grasslands of Nepal.

2022 ◽  
Author(s):  
Shyam Kumar Thapa ◽  
Joost de Jong ◽  
Anouschka Hof ◽  
Naresh Subedi ◽  
Laxmi Joshi ◽  
...  
Keyword(s):  
Crude Protein ◽  
Large Scale ◽  
Forage Quality ◽  
Chemical Properties ◽  
Grazing Intensity ◽  
Mean Value ◽  
Burned Areas ◽  
Short Period ◽  
Pyric Herbivory ◽  
Spatio Temporal

Indiscriminate fire is rampant throughout subtropical South and Southeast Asian grasslands. However, very little is known about the role of fire and pyric herbivory on the functioning of highly productive subtropical monsoon grasslands lying within Cwa-climatic region. We collected grass samples from 60 m x 60 m plots and determined vegetation physical and chemical properties at regular 30-day intervals from April to July 2020, starting from 30 days after fire to assess post-fire regrowth forage quality. We counted pellet groups for the same four months from 2 m x 2 m quadrats that were permanently marked with pegs along the diagonal of each 60 m x 60 m plot to estimate grazing intensity to the progression of post-fire regrowth. We observed strong and significant reductions in crude protein (mean value 9.1 to 4.1 [55% decrease]) and phosphorus (mean value 0.2 to 0.11 [45% decrease]) in forage collected during different time intervals i.e., from 30 days to 120 days after fire. Mesofaunal deer utilised the burned areas extensively for a short period, i.e., up to two months after fire when the burned areas contained short grasses with a higher level of crude protein and phosphorus. Grazing intensity of chital (Axis axis) to post-fire regrowth differed significantly over time since fire, with higher intensity of use at 30 days after fire. Grazing intensity of swamp deer (Rucervus duvaucelii) did not differ significantly until 90 days after fire, however, decreased significantly after 90 days since fire. Large-scale indiscriminate single event fires thus may not fulfil nutritional requirements of all species in mesofaunal deer community in these subtropical monsoon grasslands. We recommend for a spatio-temporal manipulation of fire to reinforce grazing feedback and to yield for the longest possible period a reasonably good food supply for the conservation of mesofaunal deer.

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