Search results for "Remote Sensing"

Advances in the Retrieval and Interpretation of Solar-Induced Vegetation Chlorophyll Fluorescence Using Passive Remote Sensing Techniques

2021

In the context of the development and implementation of the Fluorescence Explorer (FLEX) mission, selected in 2015 by the European Space Agency (ESA) as the 8th Earth Explorer, many recent developments in the field of vegetation chlorophyll fluorescence have taken place in the last years. These advances include new retrieval approaches, more accurate and robust, and a much better understanding of the variability of the signal, facilitating the interpretation of the dynamical changes and the usage of the fluorescence signal in Earth models and applications. Although chlorophyll fluorescence is related to the actual photosynthetic activity of the plants, the link between fluorescence and phot…

Combining the FAO56 agrohydrological model and remote sensing data to assess water demand in a Sicilian irrigation district

2020

<p>Agricultural water use in irrigated areas plays a key role in the Mediterranean regions characterized by semi-arid climate and water shortage. In the face of optimizing irrigation water use, farmers must revise their irrigation practices to increase the drought resilience of agricultural systems and to avoid severe damages in agro-ecosystems. In this direction, during the last decades, the research has been focused on mathematical models to simulate the process of driving mass transport and energy exchanges in the Soil-Plant-Atmosphere system.</p><p>The objective of the paper was to test the suitability of the combination of FAO56 agro-hydrologi…

Kernel Spectral Angle Mapper

2016

This communication introduces a very simple generalization of the familiar spectral angle mapper (SAM) distance. SAM is perhaps the most widely used distance in chemometrics, hyperspectral imaging, and remote sensing applications. We show that a nonlinear version of SAM can be readily obtained by measuring the angle between pairs of vectors in a reproducing kernel Hilbert spaces. The kernel SAM generalizes the angle measure to higher-order statistics, it is a valid reproducing kernel, it is universal, and it has consistent geometrical properties that permit deriving a metric easily. We illustrate its performance in a target detection problem using very high resolution imagery. Excellent re…

Investigating diffuse CO2 degassing in tectonically active areas by groundwater

GIS AND REMOTE SENSING IN HYDROLOGY: SELECTED PRACTICAL APPLICATIONS. Proceedings of the ECO-GEOWATER conference - GIS for International river basin …

2004

Assessing opportunities for water savings in large-scale pressurized irrigation systems using actual evapotranspiration retrieved by surface energy b…

Remote sensing allows the observation of large land stretches and the acquisition of worthwhile information that can be used efficaciously in agro-hydrologic systems. Satellite imagery associated to computational models provide a reliable resource in estimating evapotranspiration (ET) fluxes based on surface energy balance. On irrigated crops, quantifying the spatial distribution of actual ET enables a broad range of applications such as irrigation management, monitoring water distribution, assessing crop water status and irrigation system performance. The general objective of the research was to propose a methodology to estimate ET by using Landsat Thematic Mapper (TM) images and surface e…

Recent advances in ground based ultraviolet remote sensing of volcanic SO2 fluxes

2011

Object oriented methodology for change detection technique: the case of Scopello-Sicily

2014

This paper describes a change detection approach based on an object-based classification of remote sensing data for the change detection. The history of urban growth and urbanisation reveals that urban areas belong to the most dynamic land cover types on earth. The trend of urban growth is usually towards the urban-rural fringe where there are less built areas, irrigation and other water management systems. Regardless of the regional economic importance, urban growth, particularly the expansion of residential and commercial land use towards the periphery of urban areas, has an impact on the ecosystem. It is evident that such trend of urban growth has an impact on natural resources and on la…

Reservoir monitoring using satellite SAR and GNSS: a case study in southern Italy

2018

Recently, it has been demonstrated that it is possible to relate water levels of a reservoir with its dam displacements. Water levels were determined via remote sensing, while dam displacements were measured via Global Navigation Satellite System (GNSS). Results have shown that displacements and water levels are correlated.Water levels at the Magazzolo reservoir in southern Italy were firstly retrieved using two remote sensing approaches: by visual matching between the reservoir shoreline and contour lines, and by evaluating the surface extent via unsupervised classification to estimate the water levels with an area/depth relation. Dam displacements were measured using GPS receivers on the …

Fluorescence estimation in the framework of the CEFLES2 campaign

2011

International audience; Chlorophyll fluorescence (ChF) is a relevant indicator of the actual plant physiological status. In this article different methods to measure ChF from remote sensing are evaluated: The Fraunhofer Line Discrimination (FLD), theFluorescence Radiative Method (FRM) and the improved Fraunhofer Line Discrimination (iFLD). The three methods have been applied to data acquired in the framework of the CarboEurope, FLEX and Sentinel-2 (CEFLES2) campaign in Les Landes, France in September 2007. Comparing with in situ measurements, the results indicate that the methods that provide the best results are the FLD and the iFLD with root mean square errors (RMSEs) of 0.4 and 0.5 mW m-…