Satellite-derived time-series of shoreline change along the Pacific Rim

This repository contains 40 years of tidally-corrected shoreline change time-series for most sandy coastlines around the Pacific Rim derived from Landsat imagery. The time-series were last updated in May 2025. For the latest data always refer to http://coastsat.space/. The dataset was used to investigate the impact of ENSO on beach erosion and accretion in:- Vos, K., Harley, M.D., Turner, I.L. et al. Pacific shoreline erosion and accretion patterns controlled by El Niño/Southern Oscillation. Nat. Geosci. 16, 140–146 (2023). https://doi.org/10.1038/s41561-022-01117-8 CoastSat was used to map shoreline changes on Landsat 5, Landsat 7 and Landsat 8 imagery between 1984 and 2025. The Coastsat toolbox is publicly available at https://github.com/kvos/CoastSat and described in Vos et al. 2019, https://doi.org/10.1016/j.envsoft.2019.104528. The time-series of shoreline change were tidally-corrected along cross-shore transects using tide levels from a global tide model (FES2022) and a satellite-derived estimate of the beach slope (as described in Vos et al. 2020, "Beach slopes from satellite-derived shorelines", https://doi.org/10.1029/2020GL088365). This dataset covers wave-dominated sandy coasts in the Pacific basin where Landsat imagery was available, including a total of 3,000 beaches and more than 100,000 cross-shore transects (100-m alongshore spaced). This includes coastlines in Australia, New Zealand, Japan, Chile , Peru, Mexico and USA (California and Hawaii only). The data is structured as follows: There is a folder for each country (e.g. Australia) In the country folder, there is a folder for each site (e.g. aus0001, aus0002 etc) In the site folder, there are 4 CSV files: time_series_tidally_corrected.csv: this file contains the tidally-corrected time-series of shoreline change along each transect belonging to the site (e.g. aus0001-0001, aus0001-0002 etc). This is the final product used for coastal change analyses. time_series_raw.csv: this file contains the raw time-series of shoreline change, which have not be tidally-corrected. Note that each image is taken at a different stage of the tide. tide_levels_fes2022: this file contains the tide levels at the time of image acquisition extracted from FES2022 (global tide model publicly available on AVISO+). transect_coordinates_and_beach_slopes.csv: this file contains the coordinates (in WGS84 lat/lon coordinates) as well as the estimated beach slope for each transect, including confidence intervals. In addition, there are four geospatial layers (.GEOJSON) which contain important spatial information: polygons.geojson: this layer contains the polygons that were used to run CoastSat for each beach. shorelines.geojson: this layer contains the sandy shorelines that were used to generate the cross-shore transects (also used as reference shorelines in CoastSat). Each beach has the following attributes: beach length, median orientation, median slope, and mean springs tidal range. transects.geojson: this layer contains the cross-shore transects, which are spaced 100 m along each beach. Each transect has the following attributes: orientation, beach slope, linear trend (in m/year), alongshore distance relative to the northern end of the beach (absolute and normalised). transects_edit.geojson: this layer is the same as transects.geojson but the transects that are not suitable for shoreline mapping were manually deleted (rocky shores, submerged reef, coastal lagoons and inlets, coastal defences etc...). transects_ENSO.geojson: this layer (similar to transects.geojson) contains the transects that were used to analyse ENSO effects on shoreline changes in the Pacific (a total of 83,000).本仓库存储了环太平洋绝大多数沙质海岸线的40年潮汐校正海岸线变化时间序列，数据源自Landsat卫星影像，该时间序列最后更新于2025年5月。如需获取最新数据，请访问http://coastsat.space/。 该数据集曾用于研究厄尔尼诺-南方涛动（El Niño/Southern Oscillation, ENSO）对海滩侵蚀与淤积的影响，相关研究成果发表于：Vos, K., Harley, M.D., Turner, I.L. 等. 受厄尔尼诺-南方涛动调控的太平洋海岸线侵蚀与淤积格局. "Nat. Geosci.", 16, 140–146 (2023). https://doi.org/10.1038/s41561-022-01117-8 本数据集基于CoastSat工具，对1984年至2025年间的Landsat 5、Landsat 7及Landsat 8卫星影像开展海岸线变化制图工作。CoastSat工具包已开源，公开地址为https://github.com/kvos/CoastSat，相关方法说明详见Vos等人2019年发表的研究（https://doi.org/10.1016/j.envsoft.2019.104528）。海岸线变化时间序列通过沿垂直岸线断面（cross-shore transects）进行潮汐校正，校正过程采用了全球潮汐模型FES2022的潮位数据，以及卫星反演得到的海滩坡度数据（具体方法详见Vos等人2020年发表的《基于卫星反演海岸线的海滩坡度估算》，https://doi.org/10.1029/2020GL088365）。 本数据集涵盖太平洋流域内有Landsat影像可用的以波浪为主导的沙质海岸，共计3000处海滩及超过10万条垂直岸线断面（沿岸布设间距为100米），涉及澳大利亚、新西兰、日本、智利、秘鲁、墨西哥及美国（仅加利福尼亚州与夏威夷州）的海岸线。 数据组织形式如下： 1. 每个国家对应一个独立文件夹（例如Australia） 2. 国家文件夹内包含各研究位点文件夹（例如aus0001、aus0002等） 3. 每个位点文件夹内包含4个CSV格式文件： - time_series_tidally_corrected.csv：存储该位点所有断面的潮汐校正后海岸线变化时间序列，是用于海岸变化分析的最终成果数据。 - time_series_raw.csv：存储未经潮汐校正的原始海岸线变化时间序列。需注意，每景影像均对应不同的潮汐相位。 - tide_levels_fes2022.csv：存储从FES2022全球潮汐模型（可在AVISO+平台公开获取）中提取的影像获取时刻潮位数据。 - transect_coordinates_and_beach_slopes.csv：存储各断面的坐标（采用WGS84经纬度格式）、估算得到的海滩坡度及置信区间。 此外，本数据集还包含4个.GEOJSON格式的地理空间图层，用于存储关键空间信息： - polygons.geojson：包含用于对各海滩运行CoastSat工具的多边形区域。 - shorelines.geojson：包含用于生成垂直岸线断面的沙质海岸线（同时作为CoastSat的参考海岸线）。每个海滩包含以下属性：海滩长度、中位走向、中位坡度及平均大潮潮差。 - transects.geojson：包含沿各海滩以100米间距布设的垂直岸线断面。每个断面包含以下属性：走向、海滩坡度、线性变化速率（单位：米/年）、相对于海滩北端的沿岸距离（含绝对距离与归一化距离）。 - transects_edit.geojson：与transects.geojson内容一致，但已手动剔除不适用于海岸线制图的断面（如岩质海岸、淹没礁、海岸潟湖与海湾、海岸防护设施等）。 - transects_ENSO.geojson：该图层格式与transects.geojson类似，包含用于分析太平洋区域ENSO对海岸线变化影响的断面（共计8.3万条）。