Why あります instead of です in this sentence?


In the following sentence (from [here](https://nhkeasier.com/2019/03/13/)),

> 北海道札幌市の円山動物園に、ミャンマーから来た３頭の象をみんなに見せるための広い場所と建物ができました。[...] 広さは５０００m²以上
> **あります** 。

I would have expected です instead of あります: 広さ = ５０００m²以上.




> 「広さは５０００m²以上 **あります** 。」

is a perfectly natural-sounding sentence.

**「あります」 can be replaced by 「です」, but that will change rather drastically the
basic grammar (if not the meaning) of the sentence.**

In the original sentence, 「５０００m²以上」 functions adverbially to modify the verb
phrase 「あります」. As discussed [in this
Q&A](https://japanese.stackexchange.com/questions/65398/different-ways-to-say-
several), number-related phrases can function **_adverbially_** in Japanese.
From my own experience with Japanese-learners, however, they seem to have
difficulty getting used to this concept.

It is more natural (or more "originally Japanese") to say:

「リンゴが **むっつ** あります。」 ← 「むっつ」 functions **_adverbially_**.

than to say:

「むっつのリンゴがあります。」 ← 「むっつの」 functions **_adjectivally_**.

Thus, in the sentence you were thinking of:

> 「広さは５０００m²以上 **です** 。」

「５０００m²以上」 functions as a **_noun_**.

