Phelps_Rd_Parcel_Boundary

This layer is a representation of the Santa Barbara County Assessor Parcel maps created for tax assessment purposes only. This layer was originally built in the late 1990's by digitizing Assessor map pages and first rubber sheeting to Assessor book indexes that were COGOed for this project and those indexes to USGS Quadrangle maps and County Flood Control topo maps. In 1998, the Assessor purchased a GPS road centerline to acquire better positional accuracy and the full parcel layer was adjusted. In 2000 the County acquired its first full county digital orthoimagery, which enabled a better ortho rectified control in many areas to improve the accuracy of the Basemap. Overtime, the spatial accuracy of this layer has improved significantly by COGOing entire Assessor Parcel Map pages and new subdivisions then rubber sheeting to those pages. When geodetic control first started showing up on recorded subdivision maps, we were able to start placing COGOed parcels to their exact location. As countywide orthoimagery gets more accurate and the number of Record of Survey and subdivision maps record with geodetic control increases, the greater the positional accuracy of the parcels on this layer will increase. Parcel polygon attributes have been updated to include Assessor property characteristics as well.本图层为仅用于税务评估目的制作的圣巴巴拉县评估员宗地地图（Assessor Parcel Maps）的可视化呈现。本图层最初于20世纪90年代末构建，流程为先将评估员宗地地图页面数字化，再将其首次橡皮校正（rubber sheeting）至经本项目坐标几何（COGO）处理的评估员手册索引，随后将该索引匹配至美国地质调查局（USGS）标准分幅地图及县防洪局地形图。1998年，评估部门采购了GPS道路中心线数据以提升空间定位精度，随后对完整宗地图层进行了调整。2000年，该县获取了首套全县范围的数字正射影像（digital orthoimagery），使得多个区域可采用更精准的正射校正控制点，进而提升了底图（Basemap）的精度。随着时间推移，通过对全部评估员宗地地图页面及新增分区进行坐标几何处理，并将其橡皮校正至对应页面，本图层的空间精度得到了显著提升。当实测分区地图首次出现大地测量控制点（geodetic control）后，我们便可将经坐标几何处理的宗地放置于其精确位置。随着全县正射影像精度不断提升，且带有大地测量控制点的测绘记录与分区地图备案数量持续增加，本图层中宗地的定位精度也将进一步提高。宗地多边形的属性字段也已更新，同步纳入了评估部门的物业特征信息。