Google search rankings have been updated to punish websites that load the top of their pages with adverts and force visitors to scroll down to view content.

Google has concluded that its users are bothered by this type of layout so it will begin penalising them in search results, the company said in a blog post.

"If you click on a website and the part of the website you see first either doesn't have a lot of visible content above-the-fold or dedicates a large fraction of the site's initial screen real estate to ads, that's not a very good user experience. Such sites may not rank as highly going forward," wrote Matt Cutts, a Google engineer who is considered the company's main authority on search engine optimisation (SEO).

Google will not punish websites that place ads at the top of their pages to what the company considers "a normal degree" but rather those with an "excessive" amount of ads that make it hard for users to find the site's original content.

"This new algorithmic improvement tends to impact sites where there is only a small amount of visible content above-the-fold or relevant content is persistently pushed down by large blocks of ads," Cutts wrote. Google forecasts that this particular algorithmic tweak will impact the order of results in less than 1% of searches.

As often happens whenever Google introduces search algorithm changes, webmasters are already chiming in, and some aren't very happy, as evidenced by some of the comments left on Cutts' blog post.

Several commenters argue that it's hypocritical of Google to punish sites for something that they believe Google itself is often guilty of, while others suggest that it shouldn't be Google's business how sites decide to lay out their ads, especially when the Google policy could impact how effective the ads are.