关键词: GEE, 亚马逊生态区, 火灾, 时空特征, MODIS, 降水

Abstract: The fire happened in the Amazon in 2019 attracted worldwide attention. There are many problems to be solved with respect to the fire. Where exactly was the burning area concentrated? The duration and calamity degree also need to be explored. It is unclear whether there was a serious meteorological drought with less abnormal precipitation. Based on the MOD14A2 fire products, MCD64A1 burning sites, precipitation, surface cover types and other multi source data, we investigated the spatial and temporal variations of the 2019 fire in the Amazon using the geographic information system and remote sensing technology. The spatiotemporal correlation between the 2019 fire and precipitation was analyzed. The cause of fire was reasonably presumed using Spearman correlation coefficient and spatial correlation analysis method. The results showed that the fires in the Amazon had obvious temporal and spatial variations. Fires usually happened during the period from the end of July to the end of September, and were mainly distributed in Brazil and Bolivia in the southern part of the study area. Fires mainly occurred in the evergreen broadleaved forest and savanna. There was a significant negative correlation between precipitation and the number of fires with a delay of 1-2 months, which affected the temporal distribution of fires. However, the spatial correlation coefficient was close to 0, indicating no direct spatial correlation between precipitation and fire. Moreover, some fires were distributed in the area where human activities were frequent, which was probably related to human factors.

Key words: Google Earth Engine (GEE), Amazon ecological region, fire, spatiotemporal characteristics, MODIS, precipitation.