Cartographic Accuracy Standard (CAS) of the digital terrain model of the digital and continuous cartographic base of the state of Amapá: case study in the city of Macapá

Abstract: The Cartographic Accuracy Standard (CAS) is a quality parameter used by the Brazilian standard to estimate the positional quality of cartographic products in their degree of precision, also including altimetry. The Digital and Continuous Cartographic Base of Amapá - BCDCA has a large amount of freely available spatial information, for the study of its territory within the state of Amapá. This project, a partnership between the Government of the State of Amapá and the Directorate of Geographical Services of the Brazilian Army (DSG), obtained a large amount of SAR data by interferometry. Among the resulting products, the Digital Terrain Model - DTM has a wide range of applications: watershed analysis, infrastructure program, diagnosis of environmental risks and so many others. Therefore, the present work aims to evaluate the altimetric data (DTM) provided by the BCDCA through 2172 orthometric points calculated from the Brazilian Network for Continuous Monitoring - RBMC measured in the field in the city of Macapá, capital of the State of Amapá. For the level curves, the results presented class A for the 1: 10 000 scale, at an equidistance of 5 m, showing that the DTM product is highly reliable for urban applications.

摘要：制图精度标准（Cartographic Accuracy Standard, CAS）是巴西官方标准中用于评估制图产品位置精度质量的参数，同时亦涵盖高程精度维度。阿马帕州数字化连续制图基底（Digital and Continuous Cartographic Base of Amapá, BCDCA）包含大量可免费获取的空间信息，可用于该州境内的领土研究。本项目由阿马帕州政府与巴西陆军地理服务局（Directorate of Geographical Services of the Brazilian Army, DSG）合作开展，通过干涉测量技术获取了大量合成孔径雷达（Synthetic Aperture Radar, SAR）数据。在其产出的各类产品中，数字地形模型（Digital Terrain Model, DTM）应用场景广泛，可用于流域分析、基础设施规划、环境风险诊断等诸多领域。因此，本研究旨在借助阿马帕州首府马卡帕市野外实测的巴西连续监测网络（Brazilian Network for Continuous Monitoring, RBMC）所计算得到的2172个正高控制点，对阿马帕州数字化连续制图基底（BCDCA）提供的高程数据（DTM）进行精度评估。针对等高线而言，当比例尺为1:10000、等高距为5米时，其精度等级达到A级，这表明该DTM产品在城市应用场景中具备极高可靠性。