Tree Cover Dynamics CONUS Dataset

The Tree Cover Dynamics (TCD) Conterminous United States (CONUS) dataset is a suite of 30 m wall-to-wall products, derived from USGS Landsat-4, Landsat-5 and Landsat-7 Collection 1 Analysis Ready Data (ARD), defining for each year: (i) the estimated percent tree cover (PTC), (ii) if tree cover loss is detected, the estimated percent tree cover decrease from the previous year (ΔPTC), (iii) if tree cover loss is detected, the Landsat acquisition dates bounding the tree cover loss event (i.e., the last valid observation before the loss, and the first valid observation after the loss) and (iv) a forest status thematic map (three thematic classes: stable forest, stable non-forest, forest cover loss).
The products are available for every year from 1985 to 2019.
The dataset is provided as georeferenced GeoTIFF images, defined in the CONUS Albers Equal-Area Conic map projection at 30m resolution.

美国本土（Conterminous United States, CONUS）树木覆盖动态（Tree Cover Dynamics, TCD）数据集是一套30米分辨率的全域覆盖产品套件，其数据源自美国地质调查局（USGS）Landsat-4、Landsat-5及Landsat-7 Collection 1分析就绪数据（Analysis Ready Data, ARD），可为每一年度提供以下四类信息：(i) 估算树木覆盖百分比（Percent Tree Cover, PTC）；(ii) 若检测到树木覆盖损失，则估算相较于上一年的树木覆盖百分比降幅（ΔPTC）；(iii) 若检测到树木覆盖损失，记录界定该损失事件的Landsat影像成像日期，即损失发生前的最后一次有效观测成像日期与损失发生后的首次有效观测成像日期；(iv) 森林覆盖状况专题图，包含3个专题类别：稳定森林、稳定非森林、森林覆盖损失。该产品套件覆盖1985年至2019年的每一个年份。本数据集以地理参考GeoTIFF图像形式提供，采用CONUS阿尔伯斯等面积圆锥地图投影，分辨率为30米。