Using Fisher information to track stability in multivariate systems

With the current proliferation of data, the proficient use of statistical and mining techniques offer substantial benefits to capture useful information from any dataset. As numerous approaches make use of information theory concepts, here, we discuss how Fisher information (FI) can be applied to sustainability science problems and used in data mining applications by analysing patterns in data. FI was developed as a measure of information content in data, and it has been adapted to assess order in complex system behaviour. The main advantage of the approach is the ability to collapse multiple variables into an index that can be used to assess stability and track overall trends in a system, including its regimes and regime shifts. Here, we provide a brief overview of FI theory, followed by a simple step-by-step numerical example on how to compute FI. Furthermore, we introduce an open source Python library that can be freely downloaded from GitHub and we use it in a simple case study to evaluate the evolution of FI for the global-mean temperature from 1880 to 2015. Results indicate significant declines in FI starting in 1978, suggesting a possible regime shift.

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On the scaling of climate impact indicators with global mean temperature increase: a case study of terrestrial ecosystems and water resources

Climatic Change ◽

10.1007/s10584-017-1911-6 ◽

2017 ◽

Vol 141 (4) ◽

pp. 775-782 ◽

Cited By ~ 4

Author(s):

Akemi Tanaka ◽

Kiyoshi Takahashi ◽

Hideo Shiogama ◽

Naota Hanasaki ◽

Yoshimitsu Masaki ◽

...

Keyword(s):

Water Resources ◽

Temperature Increase ◽

Terrestrial Ecosystems ◽

Climate Impact ◽

Global Mean Temperature ◽

Mean Temperature ◽

Impact Indicators ◽

Global Mean

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Using Fisher information to assess stability in the performance of public transportation systems

Royal Society Open Science ◽

10.1098/rsos.160920 ◽

2017 ◽

Vol 4 (4) ◽

pp. 160920 ◽

Cited By ~ 7

Author(s):

Nasir Ahmad ◽

Sybil Derrible ◽

Heriberto Cabezas

Keyword(s):

Fisher Information ◽

Public Transportation ◽

Regime Shift ◽

Transportation Systems ◽

Regime Shifts ◽

Monthly Data ◽

Multiple Variables ◽

The Stability ◽

Public Transportation Systems ◽

Lasting Change

Public transportation systems (PTS) are large and complex systems that consist of many modes operated by different agencies to service entire regions. Assessing their performance can therefore be difficult. In this work, we use concepts of Fisher information (FI) to analyse the stability in the performance of PTS in the 372 US urbanized areas (UZA) reported by the National Transit Database. The key advantage of FI is its ability to handle multiple variables simultaneously to provide information about overall trends of a system. It can therefore detect whether a system is stable or heading towards instability, and whether any regime shifts have occurred or are approaching. A regime shift is a fundamental change in the dynamics of the system, e.g. major and lasting change in service. Here, we first provide a brief background on FI and then compute and analyse FI for all US PTS using monthly data from 2002 to 2016; datasets include unlinked passenger trips (i.e. demand) and vehicle revenue miles (i.e. supply). We detect eight different patterns from the results. We find that most PTS are seeking stability, although some PTS have gone through regime shifts. We also observe that several PTS have consistently decreasing FI results, which is a cause for concern. FI results with detailed explanations are provided for eight major UZA.

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Simultaneous Carbon Storage in Arable land and Anthropogenic Products (CSAAP): demonstrating a new concept towards well below 2°C

10.31224/osf.io/cmvtu ◽

2021 ◽

Author(s):

SHEN Zhou ◽

Ligia Barna ◽

Shivesh Kishore Karan ◽

Lorie Hamelin

Keyword(s):

Carbon Dioxide ◽

Carbon Storage ◽

Carbon Budget ◽

Arable Land ◽

Marginal Lands ◽

Global Mean Temperature ◽

Negative Emission ◽

French Case ◽

Global Mean

The removal of additional carbon dioxide from the atmosphere is indispensable for controlling global warming. This study proposed the concept of ‘biopump’, as plants capable of significantly transferring carbon into the soil. The Carbon Storage in Arable land and Anthropogenic Products (CSAAP) relates to the cultivation of ‘biopumps’ on marginal arable lands poor in soil organic carbon (SOC) and their conversion into long-lived anthropogenic products. Based on a list of twenty-seven biopumps assembled from a literature review, this study proposed a method for the regional prioritization of biopumps, considering among others their ability to increase SOC and adaptation. A list with eight woody and eight herbaceous biopumps was recommended for France. To illustrate the potential of the CSAAP strategy for products encompassing a variety of lifetimes, carbon flows, from biopump cultivation to biomaterial manufacturing and end-of-life, were tracked in time to calculate their influence on global mean temperature change. An illustration was performed on the basis of a French case study, where Miscanthus is grown on spatially identified marginal lands quantified as 11,187- 24,007 km2. Planting biopumps on these lands could increase by 0.23 to 0.49 Mt carbon stocked as SOC annually, which represents 0.19%- 0.41% of the annual French carbon budget during 2015-2018. If the carbon contained in the biomass is indefinitely kept in anthropogenic products, it could represent 13.07% of the same carbon budget. We concluded that biopumps could induce negative emission by 2100, with efficiency strongly depending upon carbon’ residence time in the anthroposphere.

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The Impact of COVID-19 on Hospitality Industry in Greece and Its Treasured Santorini Island

Sustainability ◽

10.3390/su13147906 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7906

Author(s):

Nikola Medová ◽

Lucie Macková ◽

Jaromir Harmacek

Keyword(s):

Social Impact ◽

Tourism Sector ◽

Challenges And Opportunities ◽

Multiple Variables ◽

Hospitality Sector ◽

Tourism And Hospitality ◽

The Impact ◽

Further Development

This paper focuses on the dynamic of the recent upheaval in the tourism and hospitality sector due to the COVID-19 epidemic in Greece and Santorini island. It uses the case study of a country one-fourth of whose GDP consists of tourism. We compare the available statistical data showing the change in variables in the previous years with 2020 and look into the new challenges and opportunities posed by the drop in the numbers of visitors and flights. We focus mainly on the economic and social impact on the destination and possible future scenarios for further development in the area. Data show a significant effect of the pandemic on multiple variables, such as the long-term trend of the importance of tourism sector in GDP in Greece, the number of flights and visitors to Greece and Santorini island, and the contribution of tourism and travel to GDP. Based on the available data, we also construct three foresight scenarios that describe the possible futures for Santorini island in terms of the pandemic evolution. These scenarios may help various stakeholders and policymakers to be better prepared for different developments that may appear.

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Estimates of Uncertainty in Predictions of Global Mean Surface Temperature

Journal of Climate ◽

10.1175/jcli4012.1 ◽

2007 ◽

Vol 20 (5) ◽

pp. 843-855 ◽

Cited By ~ 19

Author(s):

J. A. Kettleborough ◽

B. B. B. Booth ◽

P. A. Stott ◽

M. R. Allen

Keyword(s):

Twentieth Century ◽

Energy Balance ◽

Temperature Change ◽

Radiative Forcing ◽

Balance Model ◽

Future Climate Change ◽

Model Parameters ◽

Global Mean Temperature ◽

Mean Temperature ◽

Global Mean

Abstract A method for estimating uncertainty in future climate change is discussed in detail and applied to predictions of global mean temperature change. The method uses optimal fingerprinting to make estimates of uncertainty in model simulations of twentieth-century warming. These estimates are then projected forward in time using a linear, compact relationship between twentieth-century warming and twenty-first-century warming. This relationship is established from a large ensemble of energy balance models. By varying the energy balance model parameters an estimate is made of the error associated with using the linear relationship in forecasts of twentieth-century global mean temperature. Including this error has very little impact on the forecasts. There is a 50% chance that the global mean temperature change between 1995 and 2035 will be greater than 1.5 K for the Special Report on Emissions Scenarios (SRES) A1FI scenario. Under SRES B2 the same threshold is not exceeded until 2055. These results should be relatively robust to model developments for a given radiative forcing history.

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Analytical solution for the effect of increasing CO2 on global mean temperature

Nature ◽

10.1038/316657b0 ◽

1985 ◽

Vol 316 (6029) ◽

pp. 657-657 ◽

Cited By ~ 1

Author(s):

T. M. L. Wigley ◽

M. E. Schlesinger

Keyword(s):

Analytical Solution ◽

Global Mean Temperature ◽

Mean Temperature ◽

Global Mean

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Évaluation de degré de défense de l’architecture défensive pré-coloniale en Algérie : cas des villages fortifiés

X ◽

10.4995/fortmed2020.2020.11376 ◽

2020 ◽

Author(s):

Mohand Oulmas ◽

Amina Abdessemed-Fouda ◽

Ángel Benigno González Avilés

Keyword(s):

Complex System ◽

Cultural Values ◽

Case Studies ◽

Cultural Landscape ◽

Geometrical Shape ◽

Defense System ◽

Medieval Period ◽

Architectural Features ◽

The Relationship

Assassing the defensibility of the pre-colonial defensive architecture in Algeria: case study on the medieval fortified villagesAlgeria’s pre-colonial towns of the medieval period still exist in different typologies, ranging from the isolated buildings (forts, castles) and town enclosures to whole urban units (fortified villages, defensives towns). Indeed, the constituent of these fortresses was their defense system, characterized by its large dimension, constituted essentially by the enclosure wall, and architectural features of defensiveness correlated with the outside and the inside of the fortresses. This paper aims to evaluate the relationship between physical landscape, built defensive features and cultural values of the medieval fortified villages in Algeria, two medieval fortified villages in our case “Kalaa of Beni Abbes” in Bejaia and “Kalaa of Beni Rached” in Oran, that we identified as an evolved landscape and interpreted as complex system (both defensive architecture and continuing cultural landscape). This current study consists of quantifying the defensiveness degree of these sites situated within different contexts, in fact, this method ensures to identify the strategy adopted to be protected against different invasions. However, in order to achieve this we calculate a spatial defensiveness index (DI) of these sites. The parameters of our choice are related to the implantation site, the elevation, the visibility and the geometrical shape, which allow us to estimate the defensiveness degree of the defense system of our case studies.

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Variability of surface climate in simulations of past and future

10.5194/egusphere-egu2020-8592 ◽

2020 ◽

Author(s):

Kira Rehfeld ◽

Raphaël Hébert ◽

Juan M. Lora ◽

Marcus Lofverstrom ◽

Chris M. Brierley

Keyword(s):

Climate Variability ◽

Temperature Change ◽

Temperature Variability ◽

Last Interglacial ◽

Global Mean Temperature ◽

Extreme Precipitation Events ◽

Mean Temperature ◽

Project Phases ◽

Intercomparison Project ◽

Global Mean

It is virtually certain that the mean surface temperature of the Earth will continue to increase under realistic emission scenarios. Yet comparatively little is known about future changes in climate variability. We explore changes in climate variability over the large range of climates simulated in the framework the Coupled Model Intercomparison Project Phases 5 and 6 (CMIP5/6) and the Paleoclimate Modeling Intercomparison Project Phases 3 and 4 (PMIP3/4).&#160; This consists of time slice simulations for the Pliocene, Last Interglacial, Last Glacial Maximum, the Mid Holocene and idealized warming experiments (1% CO2 and abrupt 4xCO2), and encompasses climates with a range of 12&#176;C of global mean temperature change. We examine climate variability from different perspectives: from local interannual change, to coherent climate modes and through compositing extremes. The change in the interannual variability of precipitation is strongly dependent upon the local change in the total amount of precipitation. Meanwhile only over tropical land is the change in the interannual temperature variability positively correlated to temperature change, and then weakly. In general, temperature variability is inversely related to mean temperature change - with analysis of power spectra demonstrating that this holds from intra-seasonal to multi-decadal timescales. We systematically investigate changes in the standard deviation of modes of climate variability. Overall, no generalisable pattern emerges. Several modes do show, sometimes weak, increasing variability with global mean temperature change (most notably the Atlantic Zonal Mode), but also the El Ni&#241;o/Southern Oscillation indices (NINO3.4 and NINO4). The annular modes in the Northern (Southern) hemisphere show only weakly increasing (decreasing) relationships. By compositing extreme precipitation events across the ensemble, we demonstrate that the atmospheric drivers dominating rainfall variability in Mediterranean climates persist throughout palaeoclimate and future simulations. The robust nature of the response of climate variability in model simulations, between both cold and warm climates and across multiple timescales, suggests that observations and proxy reconstructions could provide a meaningful constraint on climate variability in future projections.

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Utilization of adaptive methodology to underpin rail transportation systems: Sydney metro’s methodical formulation

Journal of Engineering Design and Technology ◽

10.1108/jedt-06-2020-0259 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Koorosh Gharehbaghi ◽

Kerry McManus ◽

Matt Myers

Keyword(s):

Complex System ◽

Triple Bottom Line ◽

Transportation Systems ◽

System Thinking ◽

Rail Transportation ◽

Bottom Line ◽

Content Type ◽

Transportation Projects ◽

Separate Dimension

Purpose As a part of adaptive and complex system thinking, geographic information systems (GIS) are beneficial particularly for transportation projects, where uncertainty is frequent. Accordingly, this paper aims to examine the utilization of GIS in line with adaptive and complex system thinking, as the basis of the methodical formulation of perceived gaps within the integrated transportation planning (ITP) specifically for the mega transportation projects. Such a framework is undertaken, as the mega transportation projects although may seem straightforward, however, are problematic and require more consideration than the traditional triple bottom line factors. Using the Sydney Metro as the case study, the outcome demonstrates the significance of the fourth separate dimension of engineering into the aforementioned bottom-line factors. Design/methodology/approach The research examines the utilization of adaptive and complex system thinking, as the basis of the methodical formulation of perceived gaps within the ITP. The use of Sydney’s Metro project is a novel example of the proposed methodical formulation and its empirical assessment and provides a better understanding of the use of mapping and planning tools for mega transportation projects. Findings Aptly, using the developed conceptual framework, this research further validates the inclusion of a separate engineering dimension with the usual triple bottom line factors. Such inclusion is paramount in responding to the existing ITP gaps found within the current literature. Originality/value This research uses GIS and ITP process to support the aforementioned adaptive and complex system thinking. This, in turn, is used as the basis of a methodical formulation framework in dealing with mega rail transportation infrastructure. To support such a proposition, Sydney Metro is examined as the basis of a case study.

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Climate variability following large volcanic eruption: CMIP6 model investigation

10.5194/egusphere-egu21-3686 ◽

2021 ◽

Author(s):

Elizaveta Malinina ◽

Nathan Gillett

Keyword(s):

Climate Variability ◽

Volcanic Eruption ◽

Volcanic Eruptions ◽

Arctic Sea Ice ◽

Evaluation Tool ◽

Global Mean Temperature ◽

Arctic Sea ◽

Global Mean Surface Temperature ◽

Krakatoa Eruption ◽

Global Mean

Volcanic eruptions are an important driver of climate variability. Multiple literature sources have shown that after large explosive eruptions there is a decrease in global mean temperature, caused by an increased amount of stratospheric aerosols which influence the global radiative budget. In this study, we investigate the changes in several climate variables after a volcanic eruption. Using ESMValTool (Earth System Model Evaluation Tool) on an ensemble of historical simulations from CMIP6, such variables as global mean surface temperature (GMST), Arctic sea ice area and Nino 3.4 index were analyzed following the 1883 Krakatoa eruption. While there is a definite decrease in the multi-model mean GMST after the eruption, other indices do not show as prominent change. The reasons for this behavior are under investigation.&#160;

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