Hugo Carrao

European Commission | ec · Energy (ENER)

The briefing "Building Trans-European Nature Network" analyses the potential of using green infrastructure to connect protected Natura 2000 sites with other natural and semi-natural landscapes.

The EEA briefing ‘Tools to support green infrastructure planning and ecosystem restoration’ looks at natural capital from the angle of building networks of natural and semi-natural areas that can help biodiversity to recover and deliver a wide range of ecosystem services. These include water purification, improving air quality, providing space for...

This report draws on a range of European-wide datasets, geospatial methods, and tools available for green infrastructure (GI) mapping. It shows how two complementary mapping approaches (physical and ecosystem based) and the three key GI principles of connectivity, multifunctionality and spatial planning are used in case studies selected in urban an...

This report draws on a range of European-wide datasets, geospatial methods, and tools available for green infrastructure (GI) mapping. It shows how two complementary mapping approaches (physical and ecosystem based) and the three key GI principles of connectivity, multifunctionality and spatial planning are used in case studies selected in urban an...

This report draws on a range of European-wide datasets, geospatial methods, and tools available for green infrastructure (GI) mapping. It shows how two complementary mapping approaches (physical and ecosystem based) and the three key GI principles of connectivity, multifunctionality and spatial planning are used in case studies selected in urban an...

Drought vulnerability assessments are the first steps in the identification of the underlying causes of drought impacts. There is no single factor or measure that can entirely represent the complexity of drought vulnerability. However, this multidimensional nature of vulnerability can be conceptualised and divided into different subgroups or compon...

Meaningful seasonal prediction of drought conditions is key information for end-users and water managers, particularly in Latin America where crop and livestock production are key for many regional economies. However, there are still not many studies of the feasibility of such a forecasts at continental level in the region. In this study, precipita...

Higher evaporative demands and more frequent and persistent dry spells associated with rising temperatures suggest that drought conditions could worsen in many regions of the world. In this study, we assess how drought conditions may develop across the globe for 1.5, 2, and 3°C warming compared to pre-industrial temperatures. Results show that 2/3...

Projections of drought hazard (dH) changes have been mapped from five bias-corrected climate models and analyzed at the global level under three representative concentration pathways (RCPs). The motivation for this study is the observation that drought risk is increasing globally and the effective regulation of prevention and adaptation measures de...

Global warming is expected to considerably change the hydrological cycle, with higher temperatures resulting in higher potential evapotranspiration (PET), as well as in changes in the spatial and temporal distribution of precipitation, including more frequent and persistent dry periods. Therefore, coherent information on plausible future drought co...

Droughts are a recurrent climatic event in many parts of the world which intensity and duration are the main causes of important economic losses and disruption in rural and urban activities. It is expected in the near future more intense droughts due to the climatic changes in the past years and, at the same time the affected territories will expan...

Abstract A global map of drought risk has been elaborated at the sub-national administrative level. The motivation for this study is the observation that little research and no concerted efforts have been made at the global level to provide a consistent and equitable drought risk management framework for multiple regions, population groups and econ...

We propose a simple, spatially invariant and probabilistic year-round Empirical Standardized Soil Moisture Index (ESSMI) that is designed to classify soil moisture anomalies from harmonized multi-satellite surface data into categories of agricultural drought intensity. The ESSMI is computed by fitting a nonparametric empirical probability density f...

An extreme heat wave occurred in Russia in the summer of 2010. It had serious impacts on humans and natural ecosystems, it was the strongest recorded globally in recent decades and exceeded in amplitude and spatial extent the previous hottest European summer in 2003. Earlier studies have not succeeded in comparing the magnitude of heat waves across...

The adequacy of meteorological drought intensity threshold levels based on deviations of monthly precipitation totals from normal climatological conditions is reconsidered. The motivation for this study is the observation that reference classification systems are fixed for all climatological regions and threshold levels have been proposed without r...

Over the past decades, a continuous rise in global air temperatures resulted in significant changes in the global hydrological cycle. Regionally increased frequencies of extreme weather events and changes in the regional extent of drylands resulted in new areas at risk of desertification, a complex process driven by socio-economic and climate-relat...

In the context of climate change characterized by rising temperature and more extreme precipitation regimes, drought is one of the most relevant natural disasters. This paper presents maps of global drought frequency, duration, and severity for the periods 1951 – 1970, 1971 – 1990, and 1991 – 2010, to give an overview of the respective drought hot...

A plethora of national and regional applications need land-cover information covering large areas. Manual classification based on visual interpretation and digital per-pixel classification are the two most commonly applied methods for land-cover mapping over large areas using remote-sensing images, but both present several drawbacks. This paper tes...

We propose a relatively simple, spatially invariant and probabilistic year-round Standardized Soil Moisture Index (SSMI) that is designed to estimate drought conditions from satellite imagery data. The SSMI is based on soil moisture content alone and is defined as the number of standard deviations that the observed moisture at a given location and...

A new version of the World Atlas of Desertification (WAD) is being compiled in the framework of cooperation between the Joint Research Centre (JRC) of the European Commission and the United Nations Environment Programme (UNEP). This initiative aims at mapping the global land degradation and desertification, as well as introducing the reader with co...

An increase in arid areas and progressing land degradation are two of the main consequences of global climate change. In the 2nd edition of the World Atlas of Desertification (WAD), published by the United Nation Environment Program (UNEP) in 1997, a global aridity map was presented. This map was based on the Food and Agriculture Organization (FAO)...

On a global basis, climate classification is one of the most widespread ways to describe climate features and climate change issues. In scientific literature, many different classifications can be found, but the most used ones are based on the Köppen scheme and its further modifications into Köppen-Trewartha (K-T) and Köppen-Geiger (K-G) schemes. F...

This study evaluates the relationship between the frequency and duration of meteorological droughts and the subsequent temporal changes on the quantity of actively photosynthesizing biomass (greenness) estimated from satellite imagery on rainfed croplands in Latin America. An innovative non-parametric and non-supervised approach, based on the Fishe...

This study proposes a drought indicator that combines the Standardized Precipitation Index (SPI), the anomalies of soil moisture and the anomalies of the fraction of Absorbed Photosynthetically Active Radiation (fAPAR). Computed at the European level, the Combined Drought Indicator (CDI) gives a synthetic and synoptic overview of the drought situat...

The main objective of this study is to evaluate the uncertainties due to sample size associated with the estimation of the standardized precipitation index (SPI) and their impact on the level of confidence in drought monitoring in Africa using high-spatial-resolution data from short time series. To do this, two different rainfall datasets, each ava...

Assessment of drought conditions requires understanding regional historical droughts as well as the impacts on human activities during their occurrences. Traditional methods for drought assessment are mainly based on water supply indices derived from precipitation time-series alone. Thus, the main limitation for developing effective real-time droug...

Numerous efforts have been made to develop models to fit multispectral reflectance and vegetation index (VI) time series from satellite images for diverse land cover classes. The common objective of these models is to derive a set of measurable parameters that are able to characterize and to reproduce the land cover dynamics of natural- and human-i...

Medium-spatial-resolution satellite images have already proved to be successful in automatic production of global land-cover maps. However, their operational use for land-cover mapping at a national scale has not yet been well established. We find that the reasons for this are not data-source dependent, but are due to the land-cover nomenclatures p...

This paper proposes an effort to include uncertainty in reference databases used to assess the accuracy of land cover maps. Five linguistic levels of confidence in land cover labelling are assigned to each sample observation and converted into fuzzy numbers. This information is introduced in a fuzzy confusion matrix and fuzzy accuracy measures, sim...

To accommodate the difficulty of identifying a single 'true' or 'reference' class, the reference data protocol of an accuracy assessment may include identifying both a primary and alternate reference land cover label along with a rating of the interpreter's confidence in the reference classification obtained for each sample location. This additiona...

The goal of this study is to evaluate the relative usefulness of high spectral and temporal resolutions of MODIS imagery data for land cover classification. In particular, we highlight the individual and combinatorial influence of spectral and temporal components of MODIS reflectance data in land cover classification. Our study relies on an annual...

Resumo Neste artigo apresentam-se as iniciativas do Instituto Geográfico Português (IGP) relacionadas com produção de cartografia temática de ocupação/uso do solo. Assim, descreve-se a Carta de Ocupação do Solo de 1990 (COS90) e de 2005 (COS2005) e o programa CORINE Land Cover (CLC). Neste artigo apresenta-se também o projecto COSMIC que tem como o...

In this paper we present the methodological approach developed by the Remote Sensing Unit (RSU) of Portuguese Geographic Institute (IGP) for the regular production and updating of land cover maps derived from medium spatial resolution satellite images in Portugal. The focus of this paper is to explain the adopted land cover nomenclature, the satell...

This is a preliminary study in the framework of an ongoing research work that aims at comparing the aptitude of MERIS and MODIS images for land cover mapping at regional scale. Overall and per class accuracies achieved with a Maximum Likelihood classification of MODIS and MERIS images acquired during August 2005, are used as a measurement of their...

This paper aims at presenting the usefulness of combining satellite optical data from the visible and infrared wavelengths with longer wavelength radar data for land cover mapping in Portugal. This is a ground-breaking study in a geographical region that does not experience continuous intra- annual dreadful atmospheric contamination that commonly j...

In this paper we present a study exploring the medium spatial resolution images of recently launched ENVISAT MERIS for land cover characterization in Portugal. The goal is to take advantage of enhanced spectral and temporal resolutions of images acquired by this sensor to discriminate properly between 19 land cover classes. We test both unitemporal...

This paper introduces a reference sample database that is being developed by the Remote Sensing Unit of the Portuguese Geographic Institute for the accuracy assessment of medium scale land cover products in Portugal. The goal is to provide the worldwide remote sensing community with sufficient data for the accurate estimation of overall and per cla...

Medium spatial resolution satellite images have been recurrently used for automatic land cover mapping of large geographical areas. Despite the innovative developments in temporal and spectral resolutions of these sensors, their spatial resolution still hampers the effective discrimination between detailed cover types within fragmented landscapes....

In this paper we explore the spectral and temporal characteristics of MERIS Level 2 full resolution imagery for land cover cartography production in Portugal. For this goal, we propose a methodology based on a multi-stage approach that combines several land cover maps, each one produced for a different month of the year using the maximum likelihood...

Remote sensing data has been extensively used to generate land cover and land use maps for a variety of purposes using automatic classification approaches. However, while major efforts have been made in the development and description of automatic techniques for land cover classification, the survey sampling for the accuracy assessment of land cove...

In this paper we present a MATLAB toolbox that was developed for the analysis and classification of medium spatial resolution satellite imagery. Its main functionality is the time series analysis of satellite imagery for the land cover char-acterization. This multi-temporal assessment is of extremely high importance, since different land cover clas...

Automatic image classification often fails at separating a large number of land cover classes that punctually may present similar spectral reflectances. To improve the classification accuracy of such situations, multi-temporal satellite data has proven valuable auxiliary information. In this paper, we present a study exploring the use fulness of in...

Imaging and sensing technologies are constantly evolving so that, now, the latest generations of satellites commonly provide with earth snapshots at very short sampling periods (daily images). It is unquestionable that this tendency towards continuous time observation will broaden up the scope of remote sensing activities: not only will it enable r...

Knowledge of land cover spatial distribution is important for many activities, including environmental monitoring, land planning, and resource management. Land cover information at the appropriate time and over large geographical regions can only be derived from satellite images. With the recent launch of MERIS, a wide range of new possibilities fo...

The reported study is the first part of an ongoing work which objective is to produce a land cover classification of continental Portugal from multi-spectral and multi-temporal MODIS satellite images acquired at a 500 m nominal resolution. Our goal is to achieve an automatic pixel level classification using a Support Vector Machine (SVM) learning a...

Forest fires affect significant areas of the Portuguese forest annually, depending upon seasonal moisture and temperature conditions. Although a large percentage of those fires are not originated by natural causes, there is still a need to develop an effective and timely warning system for fire-prevention. The combination of Earth observation (EO)...

The purpose of this study was to quantitatively evaluate the effects of scale on landscape metrics. If these are insensitive to scale then it will be possible to compare landscapes of different regions (or time periods) derived from maps produced at different spatial resolutions. The study was carried out on three Portuguese municipalities with dif...

1 carrao@cnig.pt, 2 roberto@cnig.pt, 3 nery@cnig.pt, 4 mario@cnig.pt Abstract Generalisation is an essential component of the cartographic process, albeit a slow and subjective one when implemented manually. The automation of map generalisation is a complex and challenging task. Geographic Information Systems (GIS), due to their power and spatial a...

Sessão Temática 7 -Planeamento & Ordenamento do Território Resumo O desenvolvimento da tecnologia em Sistemas de Informação Geográfica (SIG) tornou disponível um conjunto de ferramentas analíticas para a análise e ordenamento do território. Em resposta a este crescente suporte teórico e empírico, aliado a outras capacidades técnicas, diversas agênc...

With the recent launch of MERIS, a wide range of new possibilities for the periodic land cover characterization at regional scale is available. This sensor offers a combination of innovative features, such as high spectral and temporal resolutions, wide geographical coverage and improved atmospheric correction. We believe that the exploitation of d...

A methodology for fire risk mapping using satellite imagery and ancillary data, developed within PREMFIRE, a project funded by European Space Agency (ESA), is presented. The proposed method-ology is based on the combination of both structural and dynamic indices to produce an Integrated Forest Fire Risk map, to be updated daily. The structural comp...

This study evaluates the effectiveness of a previous developed methodology, in which was produced a medium scale land cover map for Portugal for 2005, when tested with up- to-date data. If proved successful, this methodology can be used on an operational basis for the establishment of an annual land cover mapping program at the national scale. The...

Updated land cover maps are increasingly needed for landscape management, biodiversity assessment, and, in general, to support environmental policies. Therefore, mapping landscape regimes that are subject to frequent change actions must be a regular process. Automatic interpretation of multispectral satellite imagery has proven to be an efficient p...

Knowledge of land cover characteristics and spatial distribution of landscape features is important for many activities, including environmental monitoring, land planning, and resource management. Amongst all those different fields of action, land cover characterization and change analyses are common tasks that undoubtedly benefit from the use of e...

An application to derive land cover change maps from satellite imagery was developed for ArcView® 3.x. from ESRI (Redlands, California). The application was implemented in five modules: the unit conversion module, the vegetation index module, the change detection module, the generalization module and the map actualization module. With this tool, no...

The accuracy assessment of land cover maps is traditionally based on reference sample observations randomly selected over the study area. It is assumed that reference sample observations, representing the "real" land cover at Earth's surface, are free of errors. However, some of these may be erroneous. These errors are sometimes due to an uncertain...