The U.S. Geological Survey Land Change Monitoring, Assessment and Projection (USGS LCMAP) has released a suite of annual land cover and land cover change products for the conterminous United States (CONUS). The accuracy of these products was assessed using an independently collected land cover reference sample dataset produced by analysts interpreting Landsat data, high-resolution aerial photographs, and other ancillary data. The reference sample of nearly 25,000 pixels and the accompanying 33-year time series of annual land cover reference labels allowed for a comprehensive assessment of accuracy of the LCMAP land cover and land cover change products. Overall accuracy (± standard error) for the per-pixel assessment across all years for the eight land cover classes was 82.5% (±0.2%). Overall accuracy was consistent year-to-year within a range of 1.5% but varied regionally with lower accuracy in the eastern United States. User's accuracy (UA) and producer's accuracy (PA) for CONUS ranged from the higher accuracies of Water (UA = 96%, PA = 93%) and Tree Cover (UA = 90%, PA = 83%) to the lower accuracies of Wetland (UA = 69%, PA = 74%) and Barren (UA = 43%, PA = 57%). For a binary change/no change classification, UA of change was 13% (±0.5%) and PA was 16% (±0.6%) for CONUS when agreement was defined as a match by the exact year of change. UA and PA improved to 28% and 34% when agreement was defined as the change being detected by the map and reference data within a ± 2-year window. Change accuracy was higher in the eastern United States compared to the western US. UA was 49% (±0.3) and PA was 54% (±0.3) for the footprint of change (defined as the area experiencing at least one land cover change from 1985 to 2017). For class-specific loss and gain when agreement was defined as an exact year match, UA and PA were generally below 30%, with Tree Cover loss being the most accurately mapped change (UA = 25%, PA = 31%). These accuracy results provide users with information to assess the suitability of LCMAP data and information to guide future research for improving LCMAP products, particularly focusing on the challenges of accurately mapping annual land cover change.

美国地质调查局土地变化监测、评估和预测 (USGS LCMAP) 发布了一套针对美国本土 (CONUS) 的年度土地覆盖和土地覆盖变化产品。这些产品的准确性是使用独立收集的土地覆盖参考样本数据集评估的，该数据集由分析员解释 Landsat 数据、高分辨率航空照片和其他辅助数据而产生。近 25,000 个像素的参考样本和随附的 33 年时间序列年度土地覆盖参考标签允许对 LCMAP 土地覆盖和土地覆盖变化产品的准确性进行全面评估。八种土地覆盖类别所有年份的每像素评估的总体准确度（± 标准误差）为 82.5% (±0.2%)。总体准确度在 1 的范围内逐年保持一致。5%，但在美国东部地区的准确性较低。CONUS 的用户准确度 (UA) 和生产者准确度 (PA) 范围从较高的水准确度（UA = 96%，PA = 93%）和树木覆盖度（UA = 90%，PA = 83%）到较低的准确度湿地（UA = 69%，PA = 74%）和贫瘠（UA = 43%，PA = 57%）。对于二元变化/无变化分类，当一致性被定义为与变化的确切年份匹配时，CONUS 的变化 UA 为 13% (±0.5%)，PA 为 16% (±0.6%)。当一致性定义为地图和参考数据在 ± 2 年窗口内检测到的变化时，UA 和 PA 分别提高到 28% 和 34%。与美国西部相比，美国东部的变化准确度更高。UA 为 49% (±0.3)，PA 为 54% (±0. 3) 变化足迹（定义为从 1985 年到 2017 年至少经历一次土地覆盖变化的区域）。对于特定类别的损失和收益，当协议被定义为精确的年份匹配时，UA 和 PA 通常低于 30%，其中树木覆盖损失是最准确映射的变化（UA = 25%，PA = 31%）。这些精度结果为用户提供信息来评估 LCMAP 数据和信息的适用性，以指导未来改进 LCMAP 产品的研究，特别是关注准确绘制年度土地覆盖变化的挑战。