the mysterious green half circle!

i was walking home from across the river and the sun was setting, so i took a bunch of pictures over the river..  it was pretty. .. see.. 

but what's this?

lens flare right?  that's what i thought..  but i was looking through the pictures i took and it showed up in all of them (except one) 

here's the pictures in the order i took them .. 

 you start to really notice it around the 5th photo, and it's pretty obvious that it's there.. even when there's no other obvious lens flares...
but cause i was looking i noticed something in the first 3 photos too.. 

it's 'further back' in the first 3.. i dont see anything in the 4th, but if you follow the path it seems to be going it could be right over the sun in that one. 

but the really weird thing!  .. i enlarged them to try and see what it was and mostly all you see is a green half circle, but on some of the closer ones you see these little dots in it.  especially the 4th from the last one.. 

i think it looks better on my phone..  but you can see it..  the three little dots along the bottom..  weird eh?
anyway..  that's my weird photo experience..  if you know about the bridge, it's' got 2 little um..  i can't thing of the word.. little areas that jut out from the main straight part..  and i stopped at the first one and took some pictures, and then walked to the next one and took some pictures too..  so there's pictures from both ends there.  so it was a few minutes anyway.
the mysterious green half circle!