Normalized Difference Vegetation Index (NDVI) for Barranquilla, Colombia, 2000-2022

This dataset is part of the ESCALA (Study of Urban Health and Climate Change in Informal Settlements in Latin America) project that was funded by the Lacuna Fund of the Meridian Institute https://lacunafund.org/.

NDVI (normalized difference vegetation index) is an indicator of vegetation health, which is calculated from the reflectance of red and infrared light from the earth's surface. This variable is represented by raster layers and has a range of values from -1 to 1 where higher values represent denser, healthier vegetation.

The dataset consists of 270 raster images where each pixel (30 m spatial
resolution) has a NDVI value for a specific date.

The data were derived from Landsat imagery available in Google Earth Engine.

Satellite imagery was processed in Google Earth Engine as follows. Images from the Landsat 5, 6, 7, 8, and 9 collections were selected for the period of interest (2000-01-01 to 2022-12-31) with a maximum cloud cover of 20%. For each image, reflectance values were calculated using scaling parameters from the product guide and a cloud and shadow mask was applied. NDVI was then calculated from the Red and NIR bands and cropped to the urban perimeter area.

本数据集隶属于拉丁美洲非正规住区城市健康与气候变化研究（ESCALA, Study of Urban Health and Climate Change in Informal Settlements in Latin America）项目，该项目由子午线研究所（Meridian Institute）的拉库纳基金（Lacuna Fund）资助，资助官网为https://lacunafund.org/。

归一化植被指数（NDVI, normalized difference vegetation index）是反映植被健康状态的指标，其通过地表红光与红外光的反射率计算得到。该变量以栅格图层形式呈现，数值范围为-1至1，数值越高则代表植被越茂密、健康。

本数据集包含270幅栅格影像，每幅影像的像素空间分辨率为30米，每个像素均对应特定日期的NDVI数值。

本数据源自谷歌地球引擎（Google Earth Engine）平台公开的陆地卫星（Landsat）影像。

卫星影像在谷歌地球引擎中按如下流程完成处理：选取2000年1月1日至2022年12月31日期间的Landsat 5、6、7、8、9系列影像，且单幅影像最大云量覆盖率不超过20%；针对每幅影像，利用产品指南中的缩放参数计算反射率，并应用云与阴影掩膜；随后基于红光与近红外波段计算NDVI，最终将影像裁剪至城市边界范围内。

搜集汇总

背景与挑战

背景概述

该数据集提供了哥伦比亚巴兰基亚地区2000年至2022年的归一化植被指数(NDVI)数据，用于监测植被健康变化。数据集包含270个30米空间分辨率的栅格图像，源自Landsat卫星影像并通过Google Earth Engine处理，适用于城市健康、环境科学等多学科研究。