6 research outputs found

    Environmental change detection in relation to landslide hazard using landsat TM imagery

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    Landslides are severe environmental hazards in mountainous areas. Nowadays, the threat of landslides to public safety has become more pronounced resulting from the burgeoning development and the increase of deforestation in hilly areas, and the increase of regional precipitation caused by global climate change. Traditional landslide risk assessment requires immense physical power to assemble different in-situ data, such as identification of landslide location and land-cover classification. This traditional data collection technique is very time consuming, and thus impossible to be applied for the large scale assessment. Remote sensing techniques, therefore, are the solutions for providing fast and up-to-date landslide assessments. This thesis focuses on the applications of multispectral Landsat data for landslide recognition. Wollongong of Australia was chosen as a test bed for this analysis. For landslide recognition analysis, three change detection techniques were employed, which were image differencing, bi-temporal linear data transformation and post-classification comparison. For the first two change detection methods, a new landslide identification procedure was developed by integrating surface change information of greenness, brightness and wetness. During the image differencing, the three surface change components were derived from Vegetation Indices (VIs), in which four different surface change composites were generated. Each composite contained three surface change bands which were greenness, brightness and wetness. For bi-temporal linear data transformation, multitemporal Kauth-Thomas (MKT) transformation was adopted for providing the three types of surface change information. In the landslide recognition analysis, the best mapping performance is yielded by the image differencing method using brightness and wetness components of Kauth-Thomas transformation and NDVI. Its omission error (i.e. percentage of actual landslide pixels which were not detected) and commission error (i.e. percentage of change pixels identified which were not landslide) are 14.4% and 3.3%, respectively, with a strong agreement (KHAT = 88.8%)

    Glacier mass balance changes and meltwater discharge

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    Vurdering av mulighetene for kartlegging av snøskred med fjernanalyse

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    I denne oppgaven undersøkes mulighetene for å bruke satellittfjernanalyse til kartlegging av snøskred som har gått. Det gjøres en teoretisk kartlegging av aktuelle metoder. Ulike sensortyper og deres egnethet for formålet vurderes. Synthetic aperture radar – SAR anses som den mest interessante sensortypen, på grunn av muligheten for å ta bilder til alle døgnets tider og under nærmest alle værforhold. På grunn av SAR geometrien vil det imidlertid i terreng med vertikalt relieff, være topografiske effekter i bildene. Dersom helningsvinkelen i terrenget overstiger insidensvinkelen i bildet og har eksposisjon mot eller fra sensoren, vil man få henholdsvis overlay og shadow. Dette er ekstreme topografiske effekter som ikke lar seg korrigere. For å undersøke i hvilken grad skredavsetningene ligger i områder med shadow og/eller overlay er det gjort en digital terrenganalyse. Basert på en digital terrengmodell og NGIs topografisk/statistiske modell for beregning av maksimal utløpslengde for snøskred, er det laget en modell som beregner mulige utløsningsområder for snøskred, deres skredbaner og utløpsområder. Resultatene fra denne modellen sammenliknes med beregninger av hvilke områder som vil dekkes av shadow og/eller layover. I testområdet i Myrkdalen i Hordaland ligger over 97 % av skredavsetningene, slik at man har innsyn med SAR, dersom man bruker stor insidensvinkel eller kombinerer ulike pass. Vinteren 2002/2003 og vinteren 2003/2004 ble det gjort et feltarbeid for å kartlegge skredavsetningenes egenskaper i forhold til snødekket i områdene rundt. En skredavsetning ble volumberegnet for å finne endringer i snødybde, det ble gravd snøprofiler i og utenfor skredavsetninger for å finne forskjeller og det ble logget temperatur i utløsningsområdet for å prøve å estimere temperaturøkning i snøen under et skred. Resultatene av disse undersøkelsene viser at skredavsetningene skiller seg vesentlig fra områdene rundt ved en markert økning i snødybde, økt overflate ruhet og manglende struktur/lagdeling i snøpakka. Selv om resultatene er positive og det teoretisk kan være mulig å kartlegge snøskred ved bruk av SAR, gjenstår praktisk utprøving der man undersøker SAR bilder mot kjente snøskred

    Eighth International Symposium “Monitoring of Mediterranean Coastal Areas. Problems and Measurement Techniques”

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    The 8th International Symposium "Monitoring of Mediterranean Coastal Areas. Problems and Measurements Techniques" was organized by CNR-IBE in collaboration with FCS Foundation, and Natural History Museum of the Mediterranean and under the patronage of University of Florence, Accademia dei Geogofili, Tuscany Region and Livorno Province. It is the occasion in which scholars can illustrate and exchange their activities and innovative proposals, with common aims to promote actions to preserve coastal marine environment. Considering Symposium interdisciplinary nature, the Scientific Committee, underlining this holistic view of Nature, decided to celebrate Alexander von Humboldt; a nature scholar that proposed the organic and inorganic nature’s aspects as a single system. It represents a sign of continuity considering that in-presence Symposium could not be carried out due to the COVID-19 pandemic restrictions. Subjects are related to coastal topics: morphology; flora and fauna; energy production; management and integrated protection; geography and landscape, cultural heritage and environmental assets, legal and economic aspects

    Proceedings of Eighth International Symposium “Monitoring of Mediterranean Coastal Areas. Problems and Measurement Techniques”

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    The 8th International Symposium "Monitoring of Mediterranean Coastal Areas. Problems and Measurements Techniques" was organized by CNR-IBE in collaboration with FCS Foundation, and Natural History Museum of the Mediterranean and under the patronage of University of Florence, Accademia dei Geogofili, Tuscany Region and Livorno Province. It is the occasion in which scholars can illustrate and exchange their activities and innovative proposals, with common aims to promote actions to preserve coastal marine environment. Considering Symposium interdisciplinary nature, the Scientific Committee, underlining this holistic view of Nature, decided to celebrate Alexander von Humboldt; a nature scholar that proposed the organic and inorganic nature’s aspects as a single system. It represents a sign of continuity considering that in-presence Symposium could not be carried out due to the COVID-19 pandemic restrictions. Subjects are related to coastal topics: morphology; flora and fauna; energy production; management and integrated protection; geography and landscape, cultural heritage and environmental assets, legal and economic aspects

    Protected Area Governance and Management

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    Protected Area Governance and Management presents a compendium of original text, case studies and examples from across the world, by drawing on the literature, and on the knowledge and experience of those involved in protected areas. The book synthesises current knowledge and cutting-edge thinking from the diverse branches of practice and learning relevant to protected area governance and management. It is intended as an investment in the skills and competencies of people and consequently, the effective governance and management of protected areas for which they are responsible, now and into the future. The global success of the protected area concept lies in its shared vision to protect natural and cultural heritage for the long term, and organisations such as International Union for the Conservation of Nature are a unifying force in this regard. Nonetheless, protected areas are a socio-political phenomenon and the ways that nations understand, govern and manage them is always open to contest and debate. The book aims to enlighten, educate and above all to challenge readers to think deeply about protected areas—their future and their past, as well as their present
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