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This dataset provides annual gridded estimates of fire locations and associated burn fraction per pixel for Alaska and Canada at approximately 500 meter (m) spatial resolution for the period 2001-2019. Gridded predictions of carbon combustion and burn depth for the same period within the Arctic-Boreal Vulnerability Experiment (ABoVE) extended domain using the burn area maps and field data are also available. Fire locations and date of burn (DOB) were detected by MODIS-derived active fire products. Burned area was primarily estimated from finer-scale Landsat imagery using a differenced Normalized Burn Ratio (dNBR) algorithm and upscaled to an approximate 500 m MODIS resolution. Aboveground combustion, belowground combustion, and burn depth were statistically modeled at the pixel level for every mapped burned pixel in the ABoVE extended domain based on field observations across Alaska and western Canada. Predictor variables included remotely sensed indicators of fire severity, topography, soils, climate, and fire weather. Quality flags for burned area and combustion are available. Fire is the dominant disturbance agent in Alaskan and Canadian boreal ecosystems and releases large amounts of carbon into the atmosphere. These data are useful for studies of disturbance, fire ecology, and carbon cycling in boreal ecosystems.
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Burned area mapping across the Arctic-boreal zone (1985-2020) with Landsat and Sentinel-2 imagery
Wildfires in the Arctic-boreal zone have increased in frequency over recent decades, carrying substantial ecological, social, and economic consequences. Remote sensing is crucial for mapping burned areas, monitoring wildfire dynamics, and evaluating their impacts. However, existing high-latitude burned area products suffer from significant discrepancies, particularly in Siberia, and their coarse spatial resolutions limit accuracy and utility. To address these gaps, we developed a convolutional neural network model to map burned areas at a 30-meter resolution across the Arctic-boreal zone using Landsat and Sentinel-2 imagery. Our model achieved promising results, with an Intersection Over Union (IOU) of 0.77 and an F1 score of 0.85 on unseen test data, performing better in North America (IOU=0.84) than Eurasia (IOU=0.72) due to differences in fire regimes and data quality. Predictions for six representative years showed our model’s burned area closely matched the median values of Landsat, MODIS, and VIIRS-based products, although alignment varied annually and spatially. Visual assessments indicated our approach was generally more accurate, notably in detecting unburned vegetation islands within fire perimeters missed by other products. This research has numerous potential applications, such as analyzing feedback between vegetation and burn patterns, characterizing spatial dynamics of unburned islands, and improving carbon emission estimates through detailed burn severity assessments. Here we have provided the primary series of scripts used to achieve the above results. In these scripts we use historical vector fire polygons to download imagery from Landsat 5, 7, 8, 9 and Sentinel-2 to train a deep learning model called a UNet++ in the Arctic-boreal zone. Imagery is downloaded from Google Earth Engine, while all other processing is done locally. The series of 6 scripts describes main steps from downloading training data, pre-processing it, training the model, and applying the model across the Arctic Boreal Zone. All scripting is done in python through .py scripts and Jupyter notebooks (.ipynb). Our study area includes Alaska, Canada and Eurasia, and we trained our model on all historical fire polygons from 1985-2020.
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- Award ID(s):
- 2019485
- PAR ID:
- 10616447
- Publisher / Repository:
- Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- deep learning wildfire Arctic
- Format(s):
- Medium: X Other: text/xml
- Location:
- Arctic-boreal zone
- Institution:
- Woodwell Climate Research Center
- Sponsoring Org:
- National Science Foundation
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