Jesús A. Anaya

Universidad de Medellín · Engineering

Las imágenes obtenidas a partir de sensores ópticos instalados en satélites tienen un altísimo contenido de nubosidad en zonas tropicales y obstruyen la observación de la superficie terrestre. Por esta razón se hace necesario crear nuevas imágenes compuestas por píxeles sin nubes, donde cada pixel puede tener una fecha distinta para un período dete...

The rapid expansion of freely available Earth observation data, combined with advancements in forest monitoring capabilities, has led to the production of a variety of datasets on forest cover and change at the national and global scales. These datasets are essential for informing science and policy. Yet, this surge in available data products comes...

Understanding the spatial and temporal trends of burned areas (BA) on a global scale offers a comprehensive view of the underlying mechanisms driving fire incidence and its influence on ecosystems and vegetation recovery patterns over extended periods. Such insights are invaluable for modeling fire emissions and the formulation of strategies for po...

Structural attributes are fundamental biophysical parameters of forest, useful for ecological and environmental monitoring and planning. Canopy height is an important input for the estimation of several biophysical parameters as aboveground biomass and carbon stock, and can be related with forest degradation, deforestation, and emission reduction....

Biomass burning is an important source of greenhouse gases (GHG) and air pollutants (AP) in developing countries. In this research, a bottom-up method was implemented for the estimation of emissions, emphasizing the validation process of aerial biomass products (AGB), which it has not been sufficiently approached from the point of view of the quant...

Monitoring water level changes is necessary to manage, conserve and restore natural, and anthropogenic lake systems. However, the in‐situ monitoring of lake systems is unfeasible due to limitations of costs and access. Furthermore, current remote sensing methods are restricted to large lakes and low spatial resolutions. We develop a novel approach...

Assessments of ecosystem service and function losses of wetlandscapes (i.e., wetlands and their hydrological catchments) suffer from knowledge gaps regarding impacts of ongoing hydro-climatic change. This study investigates hydro-climatic changes during 1976–2015 in 25 wetlandscapes distributed across the world’s tropical, arid, temperate and cold...

The assessment of BA products require a statistical approach in order to define the number and the location of validation scenes [1]. In the Northern Hemisphere South America (NHSA), = 111 LANDSAT scenes (using the Worldwide Reference System-WRS) are needed to encompass the entire region. Thus, the starting point of our method must consider the sam...

This paper proposes a validation-comparison method for burned area (BA) products. The technique considers: (1) bootstrapping of scenes for validation-comparison and (2) permutation tests for validation. The research focuses on the tropical regions of Northern Hemisphere South America and Northern Hemisphere Africa and studies the accuracy of the BA...

Geography and associated hydrological, hydroclimate and land use conditions and their changes determine 42 the states and dynamics of wetlands and their ecosystem services. The influences of these controls are not limited to 43 just the local scale of each individual wetland, but extend over larger landscape areas that integrate multiple wetlands 4...

Geography and associated hydrological, hydroclimate and land-use conditions and their changes determine the states and dynamics of wetlands and their ecosystem services. The influences of these controls are not limited to just the local scale of each individual wetland but extend over larger landscape areas that integrate multiple wetlands and thei...

Tropical forests are disappearing at unprecedented rates, but the drivers behind this transformation are not always clear. This limits the decision-making processes and the effectiveness of forest management policies. In this paper, we address the extent and drivers of deforestation of the Choco biodiversity hotspot, which has not received much sci...

The authors wish to make the following correction to this paper: The author name “Zahra Kalantary” should be “Zahra Kalantari” [...]

Geography and associated hydrological, hydroclimate and land use conditions and their changes determine 42 the states and dynamics of wetlands and their ecosystem services. The influences of these controls are not limited to 43 just the local scale of each individual wetland, but extend over larger landscape areas that integrate multiple wetlands 4...

Floodplain water flows have large volumetric flowrates and high complexity in space and time that are difficult to understand using water level gauges. We here analyze the spatial and temporal fluctuations of surface water flows in the floodplain of the Atrato River, Colombia, in order to evaluate their hydrological connectivity. The basin is one o...

The availability of water is critical in determining the distribution of species by favoring or limiting their development, and leading to the formation of different ecosystems. Thus, analyzing the trends and fluctuations of the precipitation is a key factor to understanding our planet's biodiversity. Different physical conditions exist in northwes...

p>There are large omission errors in the estimation of burned area in map products that are generated at a global scale. This error is then inherited by other models, for instance, those used to report Greenhouse Gas Emissions using a “bottom up” approach. This study evaluates temporal methods to improve burned area detection using Landsat 5-TM and...

After more than 50-years of armed conflict, Colombia is now transitioning to a more stable social and political climate due to a series of peace agreements between the government and different armed groups. Consequences of these socio-economic and political changes on ecosystems are largely uncertain, but there is growing concern about derived incr...

Colombia is one of the most biodiverse countries on Earth and is currently entering an era of tremendous societal and economic transformations. Formerly inaccessible conflict areas will face development, agricultural expansion, and intrusion of extractive industries threatening Colombia’s ecosystems and biodiversity. This constitutes a great challe...

Colombia is experiencing a tremendous societal and economic transformation with unknown consequences for its biodiversity and ecosystems. While rates of change of land cover and climate have reached inprecedented velocities, information about the state of Colombian ecosystems is becoming increasingly available and openly accessible. However, these...

This study aims to determine the wetland potential on a pixel basis on the floodplain of the Leon River: hydrology, hydrophytic vegetation and hydromorphic soils were taken into account. Field measurements and spatially explicit models were used to model surface hydrology and piezometric levels. Satellite data were used to derive inundated areas an...

The Essential Biodiversity Variables (EBV) concept proposed by GEO BON, Space Agencies, and the Earth Observation research community at large aims to support efforts for biodiversity monitoring. GOFC-GOLD and GEO BON propose a new sourcebook to promote the best operational monitoring practices for the relevant EBVs based on scientific literature, a...

Fire is an important tool in tropical forest management, as it alters forest composition, structure, and the carbon budget. The United Nations program on Reducing Emissions from Deforestation and Forest Degradation (REDD+) aims to sustainably manage forests, as well as conserve and enhance their carbon stocks. Despite the crucial role of fire manag...

Authors In addition to the core editors, a number of international experts in remote sensing, and biodiversity field measurement have contributed to the development of the Sourcebook and are thankfully acknowledged for their support. This Sourcebook is the result of a joint voluntary effort from more than 70 contributing authors from different inst...

Time series of the Normalized Burn Ratio (NBR) calculated from Landsat data were analyzed at diff erent ecoregions of Colombia and Argentina. The process included removing clouds and cloud shadows from Landsat imagery and masking areas were vegetation was removed without evidence of charcoal. Changes from vegetation to bare soils are usually classi...

This paper analyzes the reflectance obtained with a series of Landsat images processed with LEDAPS model in a region of the Colombian Andes. A total of 38 images of TM and ETM sensors were calibrated to surface reflectance using LEDAPS in order to determine difference among bands of the same sensor, difference between sensors and analyze temporal p...

A pesar de que hasta hace una década los bosques protectores del embalse La Fe estaban catalogados como áreas de conservación, los consiguientes procesos de urbanización, deforestación y minería que han tenido lugar en las zonas aledañas han llegado a poner en riesgo la provisión de agua para Medellín.

Abstract: Generating annual land cover maps in the tropics based on optical data is challenging because of the large amount of invalid observations resulting from the presence of clouds and haze or high moisture content in the atmosphere. This study proposes a strategy to build an annual time series from multi-year data to fill data gaps. The appro...

Se realizó una revisión del estado del arte de las técnicas de teledetección para la implementación de programas de mitigación de Gases de Efecto Invernadero (GEI), MDL y REDD. Para tal fin se recopiló la información documentada haciendo una clasificación de la misma en tres grandes clases de sensores: ópticos, radar y LiDAR. Posteriormente, se eva...

Land cover maps at different resolutions and mapping extents contribute to modeling and support decision making processes. Because land cover affects and is affected by climate change, it is listed among the 13 terrestrial essential climate variables. This paper describes the generation of a land cover map for Latin America and the Caribbean (LAC)...

The overall goal of this study is the change of vegetation NDVI as an approach to phenology within the context of remote sensing. Vegetation cover has different phenological patterns due to seasons at high latitude regions and climate. It is expected that this pattern can also be detected with NDVI time series in the tropical environment. Thirteen...

Este documento presenta la validación del producto global de área quemada L3JRC en Colombia utilizando el método de matrices de confusión e imágenes de satélite Landsat como sustituto a la verdad terreno. El producto L3JRC, generado por Tansey et al. en el año 2007, es un mapa de áreas quemadas obtenido por teledetección con datos del instrumento S...

Forest fires contribute to deforestation and have been considered a significant source of CO2 emissions. There are global maps that estimate the area affected by a fire using the reflectance variation of the surface. In this study, we evaluated the reliability and the causes of error of the MCD45 Burned Area Product, by applying the confusion matri...

Introducción Durante los últimos 40 años, Latinoamérica ha experimentado un proceso de cambios am-bientales sin precedentes en la historia. La de-forestación, los incendios, la expansión de la agricultura, el cambio climático y la globali-zación de la economía mundial son algunas de las principales causas. Para el estudio del cambio global, se requ...

Appropriate assessment of the accuracy of burned area products is required to assess greenhouse gas (GHG) emissions in a reliable way. This paper provides validation results for three burned area products with different pixel sizes: MCD45 (500 m), GlobCarbon (1 km), and L3JRC (1 km) for the Orinoco River basin, which is widely affected by fires, ma...

This work was developed in the framework of the Latin American Network of Monitoring and Study of Natural Resources (SERENA) in response to the need for accurate and reliable information on landcover, with a medium spatial resolution in the region of Latin America and the Caribbean (LAC). This article describes the methodology and presents the resu...

A state of the art of remote sensing techniques was made in the context of Greenhouse Gases (GHG) emissions, CDM and REDD. For this purpose the documented information was collected and classified into three major classes of sensors: optical, radar and LiDAR. In addition, we evaluated the appropriateness of each sensor in the monitoring of the REDD...

Biomass burning is a major source of greenhouse gas emissions in developing countries. In Colombia, land use change, forestry and agriculture are responsible for more than 50% of the total greenhouse gas emissions. Fire is commonly used as a mechanism for land use change. In Colombia the Llanos Orientales and the Amazonia are subject to biomass bur...

Se realizó una revisión del estado del arte de las técnicas de teledetección para la implementación de programas de mitigación de Gases de Efecto Invernadero (GEI), MDL y REDD. Para tal fin se recopiló la información documentada haciendo una clasificación de la misma en tres grandes clases de sensores: ópticos, radar y LiDAR. Posteriormente, se eva...

Caracterización de la Eficiencia del Quemado a partir del análisis de series de tiempo del índice de vegetación EVI. Resumen La eficiencia del quemado (EQ) es una variable de mucha importancia en la cuantificación de emisiones de gases efecto invernadero producidas por incendios, ya que permite estimar qué proporción de la biomasa original ha sido...

This document presents a validation of the global burned area product (L3JRC) in Colombia, using the method of the confusion matrix where Landsat images are used as a proxy for fieldwork. The product L3JRC is a burned area map based on remote sensing SPOT-VEGETATION data and generated by Tansey et al. in 2007. Determination of burned area using sat...

En Colombia, desde hace algunos años, se viene trabajando en la construcción de cartografía temática de usos del suelo escala 1:100.000, utilizando la metodología desarrollada en Europa y denominada Corine Land Cover (CLC). Esto se ha logrado con el apoyo del Instituto Forestal Nacional de Francia (ONF) a varios organismos nacionales, como el Insti...

En Colombia, desde hace algunos años, se viene trabajando en la construcción de cartografía temática de usos del suelo escala 1:100.000, utilizando la metodología desarrollada en Europa y denominada Corine Land Cover (CLC). Esto se ha logrado con el apoyo del Instituto Forestal Nacional de Francia (ONF) a varios organismos nacionales, como el Insti...

This paper presents a method to increase the level of detail of aboveground biomass estimates at a regional scale. Methods are based on empirical relationships while materials are based on MODIS products and field measurements; the area covers from 4° south up to 12° north of the Equator with a total of 1,139,012 km2 corresponding to the continenta...

Este trabajo evalúa la relación entre la textura calculada a partir de una imagen de satélite Ikonos con la diversidad y la estructura a lo largo de un corredor con 43 parcelas en los bosques andinos de Colombia. Para ello, utiliza índices de diversidad calculados en 43 parcelas y mapas detallados de Usos del Suelo que separan los bosques desde un...

This paper presents results of the AQL2004 project, which has been develope within the GOFC-GOLD Latin American network of remote sensing and forest fires (RedLatif). The project intended to obtain monthly burned-land maps of the entire region, from Mexico to Patagonia, using MODIS (moderate-resolution imaging spectroradiometer) reflectance data. T...

This paper presents a method to increase level of detail for above ground biomass estimates at a re- gional scale. The methodology and materials are based on MODIS products and field measurements corresponding to the continental area of Colombia, covering from 4 degrees south up to 12 degrees north of the Equator with a total of 1,139,012 km2 . Veg...