GFOI Central America Capacity Building

Taller sobre detección de degradación de bosques utilizando sensores remotos

Workshop on Detection of forest degradation using remote sensing

San José, 21 y 22 de mayo de 2019

acerca del workshop/about the workshop

Con el objetivo de desarrollar las capacidades técnicas de expertos costarricenses por medio de metodologías de vanguardia que están disponibles gratuitamente, SilvaCarbon en colaboración con la Universidad de Boston, y en conjunto con el Centro Nacional de Información Geoambiental (CENIGA) del Ministerio de Ambiente y Energía (MINAE), organizaron el “Taller sobre detección de degradación de los bosques utilizando sensores remotos”. Esta actividad se realizó el 21 y 22 de mayo de 2019, en San José, Costa Rica, en el marco del desarrollo del Sistema de Monitoreo de la Cobertura y el Uso de la Tierra y Ecosistemas (SIMOCUTE). (texto de la página simocute.org). Haga click en el link para acceder a la nota.

https://simocute.org/2019/05/22/tallerdetecciondegradacionforestal/

With the objective of developing the technical capabilities of Costa Rican experts through avant-garde methodologies that are freely available, SilvaCarbon in collaboration with the University of Boston, and in conjunction with the National Center for Geoenvironmental Information (CENIGA) of the Ministry of Environment and Energy (MINAE), organized the "Workshop on detection of forest degradation using remote sensing". This activity was carried out on May 21 and 22, 2019, in San José, Costa Rica, within the framework of the development of the Monitoring System for Coverage and Use of Land and Ecosystems (SIMOCUTE). (text copied from simocute.org). Please click on the link above to read the entire note.

Antecedentes

SilvaCarbon es un programa estratégico del gobierno de los EE. UU. cuyo objetivo es brindar asistencia técnica a los países que tienen una estrategia REDD+ y están desarrollando Sistemas Nacionales de Monitoreo Forestal utilizando sensores remotos. Con la intención de generar capacidades técnicas por medio de metodologías de vanguardia que están disponibles gratuitamente, SilvaCarbon en colaboración con Google Earth Engine (GEE), organizó un taller sobre detección de degradación de los bosques utilizando sensores remotos.

GEE es una plataforma basada en la Web que combina un catálogo de multi-petabytes de imágenes de satélite y conjuntos de datos geoespaciales, y que permite el análisis de gran cantidad de datos. En julio de 2018 se realizó una capacitación introductoria sobre esta plataforma que brindó información general de sus principales funcionalidades, incluyendo el editor de códigos, análisis básico de las imágenes y visualización de series de tiempo. Además, como parte de esta actividad, fue presentado un método para detectar degradación de los bosques y debido al interés de los participantes, SilvaCarbon ofreció un taller posterior para profundizar en dicho método y su posible aplicación en Costa Rica.

En este taller se abordó con mayor profundidad el mapeo de la degradación de los bosques utilizando datos nacionales, empleando y modificando el algoritmo de detección de degradación disponible en GEE.

El taller se dividió en dos partes. El primer día se centró en: a) revisar conceptos básicos de GEE y el funcionamiento del algoritmo de detección de degradación; b) analizar resultados preliminares y series de tiempo para determinar lugares donde el algoritmo no funciona apropiadamente. El segundo día se centró en analizar resultados producidos el día anterior y estimar áreas empleando el mapa generado.

Objetivos

• Revisitar los proceses aprendidos en el uso la plataforma GEE y sintaxis de JavaScript.

• Mejorar la capacidad técnica en sensores remotos: mapeo de degradación foresta y análisis de cambio usando GEE.

• Explorar y comprender el funcionamiento de las funciones y herramientas de GEE para el mapeo y monitoreo de la cobertura forestal; usando un algoritmo de mapeo degradación de los bosques creado por la Universidad de Boston.

• Identificar áreas geográficas donde el algoritmo de degradación puede ser mejorado.

BACKGROUND

SilvaCarbon is a strategic program of the US government. UU whose objective is to provide technical assistance to countries that have a REDD + strategy and are developing National Forest Monitoring Systems using remote sensing. With the intention of generating technical capabilities through avant-garde methodologies that are available for free, SilvaCarbon in collaboration with Google Earth Engine (GEE), organized a workshop on detection of forest degradation using remote sensing.

GEE is a web-based platform that combines a multi-petabyte catalog of satellite images and geospatial datasets, and allows the analysis of large amounts of data. In July 2018, introductory training was carried out on this platform, which provided general information on its main functions, including the code editor, basic image analysis and time series visualization. In addition, as part of this activity, a method to detect forest degradation was presented and due to the interest of the participants, SilvaCarbon offered a later workshop to deepen this method and its possible application in Costa Rica.

In this workshop, the mapping of forest degradation using national data was addressed in greater depth, using and modifying the degradation detection algorithm available in GEE.

The workshop was divided into two parts. The first day focused on: a) reviewing basic GEE concepts and the operation of the degradation detection algorithm; b) analyze preliminary results and time series to determine places where the algorithm does not work properly. The second day focused on analyzing results produced the previous day and estimating areas using the generated map.

Goals

• Revise the processes learned in the use of the GEE platform and JavaScript syntax.

• Improve technical capacity in remote sensing: mapping of forest degradation and change analysis using GEE.

• Explore and understand the functioning of GEE functions and tools for mapping and monitoring forest cover; using a forest degradation mapping algorithm created by Boston University.

• Identify geographic areas where the degradation algorithm can be improved.

Expositores/Trainers

Paulo Arévalo

Boston University-Department of Earth and Environment

BU PhD student Paulo Arevalo (GRS’19) works with Olofsson, focusing on forest change in his home country of Colombia using data from the mid-1990s through the present. “Before, it was like looking at a picture of when you were a kid and then looking at one when you were 25 years old and ignoring all the things that happened in between,” he says. Being able to monitor deforestation in greater detail with time series analysis has allowed him to see patterns of land change that had never been explored in depth before. For example, in the Colombian Amazon, he found that communities would clear a portion of forest for subsistence agriculture, then abandon it and move on. If left alone over years, the cleared patches can regain their forest cover. However, previously farmed patches of vegetation are likely to be occupied by other communities who might clear the land again. Both patterns can be seen in Colombia, but deforestation is more prevalent and damaging.

Arevalo, Olofsson, and their colleagues, BU PhD students Christopher Holden (CAS’11, GRS’11,’17) and Eric Bullock (GRS’22), and Curtis Woodcock, also a BU professor of earth and environment, are working with the governments of Colombia and other nations to help them monitor rainforests and meet global expectations for reducing deforestation. One of their sponsors is SilvaCarbon, a US government program under the President’s Global Climate Change Initiative that monitors deforestation and carbon emissions and looks for the best methods to measure and model environmental changes around the world. SilvaCarbon and its collaborators, like the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UN-REDD), also educate countries on how to report and reduce carbon emissions.

Deforestation affects the Earth’s carbon cycle, and Arevalo plans to find out how. Trees absorb carbon dioxide from the air as they grow and release it again when they die and decompose. Halting or even slowing deforestation could have a huge impact on the carbon cycle and, scientists expect, on climate change.