Beach Erosion during Hurricane Maria in PuertoRico

This dataset accompanies the Manuscript 'Impact of Hurricane Maria on beach erosion in Puerto Rico: remote sensing and causal inference' by Jaynise Perez-Valentin and Marc F. Muller, November 2019. beachesGIS is a zip archive that contains GIS vectors of 75 beach polygons across Puerto Rico. The vectors are provided in ESRI Shapefile format and LatLong coordinate system and have an attribute table with a beach name. TimeSeries is a csv table containing time series of shoreline position associated with each of the 75 beaches, identified by their name. Each row is an observation, columns are: - 'Name' the name of the beach, as referred to in the beachesGIS file and in the manuscript. - 'date' in yyyy-mm-dd format - 'postMaria' takes a value of 1 if the observation was taken after the Hurricane (2017-09-20), zero otherwise - 'Lat', 'Lon' the coordinates of the centroid of the beach - 'A' and 'P' the area and perimeter of the beach polygon in meters - 'w' and 'L' the estimated length and width of the beach polygon in meters. - 'sandRatio' The ratio of the beach polygon occupied by the shore (i.e sand), as measured using Sentinel 1 GRD SAR imagery - 'distance' the distance from pre-Maria shoreline position, in meters, away from the shore (i.e. positive if the beach accretes) and spatially averaged over the polygon.

本数据集配套学术论文《飓风玛丽亚对波多黎各海滩侵蚀的影响：遥感与因果推断》（作者：Jaynise Perez-Valentin与Marc F. Muller，2019年11月）。

beachesGIS为压缩归档文件，包含波多黎各75处海滩多边形的地理信息系统（GIS）矢量数据。该矢量数据采用ESRI Shapefile（ESRI形状文件）格式与经纬度（LatLong）坐标系，附带包含海滩名称字段的属性表。

TimeSeries为逗号分隔值（CSV）表格，存储上述75处海滩各自对应的海岸线位置时间序列数据，以海滩名称作为识别标识。表格每行对应一条观测记录，各字段说明如下：
- "Name"：海滩名称，与beachesGIS文件及论文中的名称保持一致；
- "date"：观测日期，格式为yyyy-mm-dd；
- "postMaria"：二元标识变量，若观测采集于飓风玛丽亚（2017年9月20日）之后则取值为1，否则为0；
- "Lat"、"Lon"：海滩多边形质心的经纬度坐标；
- "A"、"P"：海滩多边形的面积与周长，单位为米；
- "w"、"L"：海滩多边形的估算宽度与长度，单位为米；
- "sandRatio"：海滩多边形中被岸线（即沙滩区域）覆盖的面积占比，通过Sentinel 1 GRD合成孔径雷达（SAR）影像测算得到；
- "distance"：相较于飓风玛丽亚发生前的海岸线位置的空间平均偏移距离，单位为米（正值表示海滩发生淤积，即向海方向扩张）。