How to remove ads with spaces below adsense ads?

Question

I have an AdSense ad unit at the top of a mobile web page. When a 320x50 ad fills this space, there is additional free space at the bottom of the ad. There is no space when using the 320x100 ad. I did not determine the size of the div element, so the device should customize any Google ad.

Is there a way to narrow the space if a 320x50 ad is used instead of 320x100?

I thought this would be a common problem, but I could not find a solution. Thanks in advance for your help.

I think that Google initially tries to provide a 320x100 block, but ultimately provides a 320x50 block, leaving extra space. According to Google: “To increase competition for 320x100 ad sizes, we allow display ads to display 320x50 ads in this format. When this happens, the smaller ad will always be vertically aligned at the top.”