MISR Level 3 Global Cloud public Product in netCDF format covering a year V002

This file contains the MISR Level 3 Global Cloud public Product in netCDF format covering a year. MI3YCLDN_002 is the Multi-angle Imaging SpectroRadiometer (MISR) Level 3 Global Cloud Public Product in netCDF format covering a year version 2 data product. It is a global summary of the Level 1 and Level 2 cloud parameters of interest averaged over a year and reported on a geographic grid; it has multiple data layers with varying temporal resolutions of 0.5 degrees by 0.5 degrees and 2.5 degrees by 2.5-degree resolution. Data collection for this product is ongoing. The MISR instrument consists of nine push-broom cameras that measure radiance in four spectral bands. Global coverage is achieved in nine days. The cameras are arranged with one camera pointing toward the nadir, four forward, and four aftward. It takes seven minutes for all nine cameras to view the same surface location. The view angles relative to the surface reference ellipsoid are 0, 26.1, 45.6, 60.0, and 70.5 degrees. The spectral band shapes are nominally Gaussian, centered at 443, 555, 670, and 865 nm. MISR isdesigned to view Earth with cameras pointed in 9 different directions. As the instrument flies overhead, each piece of Earth's surface below is successfully imaged by all nine cameras in 4 wavelengths (blue, green, red, and near-infrared). The goal of MISR is to improve our understanding of the effects of sunlight on Earth and distinguish different types of clouds, particles, and surfaces. Specifically, MISR monitors the monthly, seasonal, and long-term trends in three areas: 1) amount and type of atmospheric particles (aerosols), including those formed by natural sources and by human activities; 2) amounts, types, and heights of clouds, and 3) distribution of land surface cover, including vegetation canopy structure.本文件包含覆盖一年时长的netCDF（网络通用数据格式）格式的MISR三级全球云公开产品数据。 MI3YCLDN_002 为版本2的多角度成像光谱辐射计（Multi-angle Imaging SpectroRadiometer，简称MISR）三级全球云公开产品数据集，采用netCDF格式存储，覆盖时长为一年。该数据集是对一级（Level 1）和二级（Level 2）云参数中关注的指标进行全年平均后得到的全球汇总结果，并以地理网格形式发布；其包含多个数据图层，空间分辨率分别为0.5°×0.5°与2.5°×2.5°。该产品的数据采集工作仍在持续进行中。 MISR仪器由9台推扫式相机组成，可采集4个光谱波段的辐射亮度数据，可在9天内完成全球覆盖。相机布局为：1台指向天底方向，4台指向飞行前方，4台指向飞行后方。全部9台相机完成同一地表位置的成像仅需7分钟。相对于地表参考椭球体的观测天顶角分别为0°、26.1°、45.6°、60.0°与70.5°。光谱波段的响应曲线近似为高斯分布，中心波长分别为443 nm、555 nm、670 nm与865 nm。 MISR的设计目标是通过9台指向不同方向的相机对地观测。当仪器飞越上空时，地表的每一处区域都会被全部9台相机以4个波段（蓝、绿、红与近红外）完成成像。MISR的研发目标是加深人类对太阳光对地球影响的认知，并区分不同类型的云、颗粒物与地表覆盖物。具体而言，MISR将从三个领域监测月度、季节与长期变化趋势：1）大气颗粒物（气溶胶，aerosols）的含量与类型，包括自然源与人为源产生的颗粒物；2）云的含量、类型与云高；3）陆地地表覆盖的分布，包括植被冠层结构。