Declaring an emergency is a standard method employed by humans to let other humans know that they think there is an emergency that everybody should be acting on.

If I see a fire in the house I am in, it might be in the grate, or it might be on the sofa. If I declare some sort of 'fire emergency', it can help to point out to other humans which of the two situations I think I am encountering and how they might therefore choose to react.

I hope this helps.

As someone who's constantly learning how to be human, I found this helpful.

I'm glad you found it helpful, though if I'm the best guide you can find, you are probably doomed.

I’ve also thought this in the past, and I know basically nil about British politics, but in the States at least, these declarations can control what pool of money you can use to work against the problem.

For example, Trump declared immigration a national emergency in an attempt to use funds to build the wall that he would not have otherwise been able to do so. See the second paragraph of https://en.m.wikipedia.org/wiki/National_Emergency_Concernin...