Satellite Data for Detecting Trans-Boundary Crop and Forest Fire Dynamics in Northern Thailand
要旨Haze and smoke problems with adverse socio-economic and health impacts have become emerging new “disaster” issues over the last few years, especially in Northern Thailand. Among various main causes are forest fires, slash-and-burning, and waste residues burning from within Thailand and neighboring countries such as Myanmar and Laos. Although real-time remote-sensed data are usually used for fire detection and monitoring, there is an equal important need to assess the fire causes and impacts over time and space, then identify suitable prevention and mitigation strategies at relevant spatio-temporal scales. This study aims to analyze available remote-sensed data to better understand spatial and temporal distribution patterns of fire occurrences among these countries and also within Thailand. Our initial findings reveal that, over the period from 2006 to 2010, the frequency of fire occurrences varies from country to country. Namely, it is highest in Myanmar, and modest in China, Thailand, Cambodia, and Laos, but low in Vietnam. However, monthly distribution analysis clearly shows a common peak across these countries during the period from February to April, which clearly indicates trans-boundary and accumulative nature of the fire issue. Our further temporal analysis at local levels, from overlay techniques, indicates that fire occurrences are subject to change over time and space, hence fire risk maps must be dynamic accordingly. Overlay with other relevant data such as forest cover and landuse can be conducted to detect distribution patterns of different fire types for initially developing spatial management strategies to minimize total fire occurrences. Further in-depth research is planned to assess various socio-economic and health impacts to identify most sensitive areas for priority remedy actions, as well as responses to these issues by different stakeholders to identify gaps to be addressed, based on these patterns identified, then finally followed by alternative options and interventions to be identified to manage these trans-boundary fires and haze problems. Technical cooperation needed is also discussed for developing more comprehensive multi-temporal geospatial database at various geographical scales for different use purposes related to haze and forest fire monitoring across the South East Asia region.