是的,意味着云层经常从卫星测量。像所有的卫星数据(实际上所有测量),它有一个不确定性,但为了这个问题的意思是云的卫星产品覆盖率已经足够好了。就我个人而言,我会犹豫相信数据在高纬度地区频繁的雪或冰的封面,因为这些是很难区分与任何形式的被动眼朝下遥感云。下图是(发布的ESA) (http://www.esa.int/Our_Activities/Observing_the_Earth/Space_for_our_climate/Highlights/Cloud_cover)和来自梅里和AATSR前环境卫星仪器。虽然标题没有指定,我怀疑它使用可见光通道,因此它只与*白天*阴沉。这将是有趣的,看看比较24小时云层![!(意味着云层,ESA)[1]][1]完整图像标题和信贷:>全球年平均云量来自三年(2007 - 09年)的环境数据。地图显示区域没有云覆盖(蓝色)以及区域几乎总是多云(红色)。晴朗的天空是立即可见的沙漠(如撒哈拉、纳米比亚和阿塔卡马)。 Regions with constant high-pressure systems are detectable, such as the Pacific. On the other hand, the North Atlantic Ocean in the mid-latitudes is mostly covered with clouds, where storms develop. The UK is often cloudy, whereas the Mediterranean shows sunny skies. Data from both the MERIS and AATSR instruments on Envisat were used. > Credits: ESA/Cloud–CCI *(On behalf of ESA and the Cloud-CCI I would like to apoligise for the [poor choice of colourmap](https://users.soe.ucsc.edu/~pang/261/f15/papers/colormapSlides.pdf), but this figure predates the time at which many of us were educated on its poor suitability)* [1]: https://i.stack.imgur.com/NMrnn.jpg