Cynips, this is "fixed" in the snapshots, and also 1.7.3( when i comes out), so unless your playing that version, your still getting this bug.
I have just done some testing, and it seem no matter what i do with optifine adjusting those, it always seems to do this only on my hi resolution texture pack. The only thing that i can find to change it is make the cloud hight higher.
Confirmed, but only happens for me when im using a hi-res texture pack. Using 1.5.1
There are so many things wrong with this bug:
1. This looks like pocket edition, so you should it the pocket edition bugtracker.
2. When does it do this? Does it do this all the time? Do some testing and see what ghe configuration is for when this happens, this means less time for the developers.
3. What device are you using? IPad? Android tablet? Who knows. Tell us.
4. What version are you running?
Please, redo this post giving more than two seconds of thought into it.