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Estimating spatio-temporal air temperature in London (UK) using machine learning and earth observation satellite data / Rochelle Schneider dos Santos in International journal of applied Earth observation and geoinformation, vol 88 (June 2020)
Titre : Estimating spatio-temporal air temperature in London (UK) using machine learning and earth observation satellite data Type de document : Article/Communication Auteurs : Rochelle Schneider dos Santos, Auteur Année de publication : 2020 Article en page(s) : 10 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme du gradient
[Termes IGN] apprentissage automatique
[Termes IGN] chaleur
[Termes IGN] classification par forêts aléatoires
[Termes IGN] ilot thermique urbain
[Termes IGN] image Aqua-MODIS
[Termes IGN] image Terra-MODIS
[Termes IGN] Londres
[Termes IGN] modèle de régression
[Termes IGN] mortalité
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] politique publique
[Termes IGN] Python (langage de programmation)
[Termes IGN] régression linéaire
[Termes IGN] santé
[Termes IGN] station météorologique
[Termes IGN] température au sol
[Termes IGN] température de l'air
[Termes IGN] zone urbaine
Résumé : (auteur) Urbanisation generates greater population densities and an increase in anthropogenic heat generation. These factors elevate the urban–rural air temperature (Ta) difference, thus generating the Urban Heat Island (UHI) phenomenon. Ta is used in the fields of public health and epidemiology to quantify deaths attributable to heat in cities around the world: the presence of UHI can exacerbate exposure to high temperatures during summer periods, thereby increasing the risk of heat-related mortality. Measuring and monitoring the spatial patterns of Ta in urban contexts is challenging due to the lack of a good network of weather stations. This study aims to produce a parsimonious model to retrieve maximum Ta (Tmax) at high spatio-temporal resolution using Earth Observation (EO) satellite data. The novelty of this work is twofold: (i) it will produce daily estimations of Tmax for London at 1 km2 during the summertime between 2006 and 2017 using advanced statistical techniques and satellite-derived predictors, and (ii) it will investigate for the first time the predictive power of the gradient boosting algorithm to estimate Tmax for an urban area. In this work, 6 regression models were calibrated with 6 satellite products, 3 geospatial features, and 29 meteorological stations. Stepwise linear regression was applied to create 9 groups of predictors, which were trained and tested on each regression method. This study demonstrates the potential of machine learning algorithms to predict Tmax: the gradient boosting model with a group of five predictors (land surface temperature, Julian day, normalised difference vegetation index, digital elevation model, solar zenith angle) was the regression model with the best performance (R² = 0.68, MAE = 1.60 °C, and RMSE = 2.03 °C). This methodological approach is capable of being replicated in other UK cities, benefiting national heat-related mortality assessments since the data (provided by NASA and the UK Met Office) and programming languages (Python) sources are free and open. This study provides a framework to produce a high spatio-temporal resolution of Tmax, assisting public health researchers to improve the estimation of mortality attributable to high temperatures. In addition, the research contributes to practice and policy-making by enhancing the understanding of the locations where mortality rates may increase due to heat. Therefore, it enables a more informed decision-making process towards the prioritisation of actions to mitigate heat-related mortality amongst the vulnerable population. Numéro de notice : A2020-448 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jag.2020.102066 date de publication en ligne : 10/02/2020 En ligne : https://doi.org/10.1016/j.jag.2020.102066 Format de la ressource électronique : url article Permalink :
in International journal of applied Earth observation and geoinformation > vol 88 (June 2020) . - 10 p.[article]Innovative geo-information tools for governance / Yola Georgiadou (2019)
Titre : Innovative geo-information tools for governance Type de document : Monographie Auteurs : Yola Georgiadou, Editeur scientifique ; Diana Reckien, Editeur scientifique Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2019 Importance : 186 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-3-03921-338-2 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] chaleur
[Termes IGN] changement climatique
[Termes IGN] énergie renouvelable
[Termes IGN] gestion de l'eau
[Termes IGN] information géographique
[Termes IGN] outil d'aide à la décision
[Termes IGN] politique publique
[Termes IGN] recherche interdisciplinaire
[Termes IGN] surveillance hydrologique
[Termes IGN] téléphone intelligent
[Termes IGN] urbanisation
Résumé : (éditeur) In current times, highly complex and urgent policy problems--e.g., climate change, rapid urbanization, equitable access to key services, land rights, and massive human resettlement--challenge citizens, NGOs, private corporations, and governments at all levels. These policy problems, often called 'wicked', involve multiple causal factors, anticipated and unanticipated effects, as well as high levels of disagreement among stakeholders about the nature of the problem and the appropriateness of solutions. Given the wickedness of such policy problems, interdisciplinary and longitudinal research is required, integrating and harnessing the diverse skills and knowledge of urban planners, anthropologists, geographers, geo-information scientists, economists, and others. This Special Issue promotes innovative concepts, methods, and tools, as well as the role of geo-information, to help (1) analyze alternative policy solutions, (2) facilitate stakeholder dialogue, and (3) explore possibilities for tackling wicked problems related to climate change, rapid urbanization, equitable access to key services (such as water and health), land rights, and human resettlements in high-, middle-, and low-income countries in the North and South. Such integrative approaches can deepen our understanding of how different levels of government and governance reach consensus, despite diverging beliefs and preferences. Due to the particularly complex spatiotemporal characteristics of wicked policy problems, innovative concepts, alternative methods, and new geo-information tools play a significant role. Note de contenu : 1- Monitoring Rural Water Points in Tanzania with Mobile Phones: The Evolution of the
2- An Interactive Planning Support Tool for Addressing Social Acceptance of Renewable Energy Projects in The Netherlands
3- The Governance Landscape of Geospatial E-Services—The Belgian Case
4- Closing Data Gaps with Citizen Science?Findings from the Danube Region
5- Tensions in Rural Water Governance: The Elusive Functioning of Rural Water Points in Tanzania
6- Evolving Spatial Data Infrastructures and the Role of Adaptive Governance
7- Wicked Water Points: The Quest for an Error Free National Water Point Database
8- What do New Yorkers Think about Impacts and Adaptation to Heat Waves? An Evaluation
Tool to Incorporate Perception of Low-Income Groups into Heat Wave Adaptation Scenarios in New York City
Numéro de notice : 25988 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/URBANISME Nature : Monographie DOI : 10.3390/books978-3-03921-338-2 En ligne : https://doi.org/10.3390/books978-3-03921-338-2 Format de la ressource électronique : URL Permalink : Responses of the structure and function of the understory plant communities to precipitation reduction across forest ecosystems in Germany / Katja Felsmann in Annals of Forest Science [en ligne], vol 75 n° 1 (March 2018)
Titre : Responses of the structure and function of the understory plant communities to precipitation reduction across forest ecosystems in Germany Type de document : Article/Communication Auteurs : Katja Felsmann, Auteur ; Mathias Baudis, Auteur ; Zachary E. Kayler, Auteur ; Heike Puhlmann, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] biodiversité végétale
[Termes IGN] chaleur
[Termes IGN] écosystème forestier
[Termes IGN] sécheresse
[Termes IGN] sous-bois
[Termes IGN] strate forestière
[Termes IGN] surveillance de la végétation
[Vedettes matières IGN] Végétation et changement climatique
Résumé : (Auteur) Key message: Understory plant communities are essential for the recruitment of trees making up future forests. Independent of plant diversity, the understory across different forest ecosystems shows considerable physiological acclimation and structural stability towards drought events, which are expected to occur more frequently in future.
Context: Understory plant communities are essential for the recruitment of trees making up the future forest. It is so far poorly understood how climate change will affect understory in beech and conifer forests managed at different intensity levels.
Aims: We hypothesized that drought would affect transpiration and carbon isotope discrimination but not species richness and diversity. Moreover, we assumed that forest management intensity will modify the responses to drought of the understory community.
Methods: We set up roofs in forests with a gradient of management intensities (unmanaged beech—managed beech—intensively managed conifer forests) in three regions across Germany. A drought event close to the 2003 drought was imposed in two consecutive years.
Results: After 2 years, the realized precipitation reduction was between 27% and 34%. The averaged water content in the top 20 cm of the soil under the roof was reduced by 2% to 8% compared with the control. In the 1st year, leaf level transpiration was reduced for different functional groups, which scaled to community transpiration modified by additional effects of drought on functional group leaf area. Acclimation effects in most functional groups were observed in the 2nd year.
Conclusion: Forest understory shows high plasticity at the leaf and community level, and high structural stability to changing climate conditions with drought events.
Numéro de notice : A2018-319 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-017-0681-7 date de publication en ligne : 22/12/2017 En ligne : https://doi.org/10.1007/s13595-017-0681-7 Format de la ressource électronique : URL article Permalink :
in Annals of Forest Science [en ligne] > vol 75 n° 1 (March 2018)[article]How web services Apples and insects / Haikou Wang in GEO: Geoconnexion international, vol 15 n° 5 (May 2016)
Titre : How web services Apples and insects Type de document : Article/Communication Auteurs : Haikou Wang, Auteur Année de publication : 2016 Article en page(s) : pp 26 - 28 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] chaleur
[Termes IGN] géopositionnement
[Termes IGN] insecte nuisible
[Termes IGN] tablette
Résumé : (éditeur) For 40 years, the Australian plague locust commission has adopted new technology as it has become available. But would Apple’s IPAD prove a good surveying tool in 40ºc heat and in the middle of inland Australia? Haikou Wang reports on the results of his tests. Numéro de notice : A2016-196 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article Permalink :
in GEO: Geoconnexion international > vol 15 n° 5 (May 2016) . - pp 26 - 28[article]Seedlings of two Acacia species from contrasting habitats show different photoprotective and antioxidative responses to drought and heatwaves / Agnieszka Wujeska-Klause in Annals of Forest Science [en ligne], vol 72 n° 4 (June 2015)
Titre : Seedlings of two Acacia species from contrasting habitats show different photoprotective and antioxidative responses to drought and heatwaves Type de document : Article/Communication Auteurs : Agnieszka Wujeska-Klause, Auteur ; Gerd Bossinger, Auteur ; Michael Tausz, Auteur Année de publication : 2015 Article en page(s) : pp 403 - 414 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] Acacia aneura
[Termes IGN] Acacia melanoxylon
[Termes IGN] analyse comparative
[Termes IGN] chaleur
[Termes IGN] photosynthèse
[Termes IGN] sécheresse
[Termes IGN] zone aride
[Termes IGN] zone humide
Résumé : (auteur) Key message : Two Acacia species adapted to contrasting habitats showed different response of photoprotective and antioxidative defence systems to imposed drought and heatwave.
Context : Predicted increases in drought frequency and intense heatwaves are expected to lead to dieback of sensitive tree species. Stomatal closure restricts CO2 input into the leaf, resulting in imbalances between light energy-driven electron transport rate and electron consumption in the Calvin cycle. Reactive oxygen species formed under these circumstances have to be kept under control by photoprotective and antioxidative defence systems.
Aims : We hypothesised that these defence systems behave differently in tree species from contrasting habitats.
Methods : Acacia aneura (adapted to arid habitats) and Acacia melanoxylon (adapted to humid habitats) were exposed to two water treatments for 50 days including two short heatwave periods. Responses were assessed by gas exchange, chlorophyll fluorescence and concentrations of antioxidants (phyllodes, roots).
Results : Photosynthesis and quantum yield of photochemistry decreased significantly in both Acacia species, especially after water was withheld in combination with the second heatwave episode. In phyllodes, the concentration of antioxidants remained unchanged until exposure to severe drought and heatwave conditions (except for A. melanoxylon where changes in glutathione concentration were observed prior to exposure to severe stress), but after water was withheld and the second heatwave occurred, oxidised forms of glutathione increased. After exposure to the second heatwave, well-watered seedlings of A. melanoxylon but not A. aneura increased ascorbic acid concentration in phyllodes. Under well-watered conditions, Acacia species also showed increased concentration of antioxidants in roots following heatwaves.
Conclusions : Both Acacia species showed photodamage to photosystem II (PSII) after water was withheld and the second heatwave imposed, but with more gradual response in A. aneura. Total concentration of investigated antioxidants increased in response to the first (A. melanoxylon) and second (A. aneura) heatwaves rather than drought stress alone.
Numéro de notice : A2015-425 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-014-0438-5 date de publication en ligne : 19/11/2014 En ligne : https://doi.org/10.1007/s13595-014-0438-5 Format de la ressource électronique : URL article Permalink :
in Annals of Forest Science [en ligne] > vol 72 n° 4 (June 2015) . - pp 403 - 414[article]MODIS-based vegetation index has sufficient sensitivity to indicate stand-level intra-seasonal climatic stress in oak and beech forests / Tomáš Hlásny in Annals of Forest Science [en ligne], vol 72 n° 1 (January 2015)PermalinkTowards a 3D spatial urban energy modelling approach / Jean-Marie Bahu in International journal of 3-D information modeling, vol 3 n° 3 (July- September 2014)PermalinkA GIS-based site identification for the seasonal storage of solar heating: Promises and pitfalls / Timothy J. Dolney in Transactions in GIS, vol 17 n° 2 (April 2013)PermalinkTemporal characteristics of thermal satellite images for urban heat stress and heat island mapping / J.E. Nichol in ISPRS Journal of photogrammetry and remote sensing, vol 74 (Novembrer 2012)PermalinkSynthesizing urban remote sensing through application, scale, data and case studies / E.A. Wentz in Geocarto international, vol 27 n° 5 (August 2012)PermalinkHome energy assessment technologies / G. Hay in GIM international, vol 24 n° 3 (March 2010)PermalinkAssimilation of remote sensed data for improved latent and sensible heat flux prediction: a comparative synthetic study / R. Pipunic in Remote sensing of environment, vol 112 n° 4 (15/04/2008)PermalinkMesoscale meteorological modeling / R.A. Pielke (2002)PermalinkMeteorology for scientists and engineers / R.B. Stull (2000)PermalinkThermodynamics of atmospheres and oceans / J.A. Curry (1999)Permalink