Sudden cosmic ray decreases: No change of global cloud cover

[1] Currently a cosmic ray cloud connection (CRC) hypothesis is subject of an intense controversial debate. It postulates that galactic cosmic rays (GCR) intruding the Earth's atmosphere influence cloud cover. If correct it would have important consequences for our understanding of climate driving processes. Here we report on an alternative and stringent test of the CRC-hypothesis by searching for a possible influence of sudden GCR decreases (so-called Forbush decreases) on clouds. We find no response of global cloud cover to Forbush decreases at any altitude and latitude.