Suggestion: add mouseovers explaining units

[jidanni]

Suggestion: add mouseovers explaining units.
E.g., here "I/km2" could have a mouseover at least saying, or even
explaining, lightnings per kilometer.

Without a mouseover the user might even think it is liters or live reports etc.

I am saying not only for this item, but for each item.

[vsinceac]

Generally the "i" control does the deal for every data layer; on the popup panel the info is more complete than a tooltip could do:

[jidanni]

@vsinceac That's great. OK, but today's users are used to sites with a lot of mouseovers and get nervous without them.
Therefore many such spots could have a mouseover saying "click ⓘ above for details".