Using Escape has some limitations:

• it stops the browser from loading pages
• Escaping performs other functions in the operating system
• Pressing Escape isn’t considered a user interaction:

  And Esc is the only keyboard key that doesn’t count as user interaction for the purposes of transient activation.

Why other alternative keys (^ Ctrl, ⎇ Alt, ⌥ Option, ) are not better, because they have tradeoffs.

⇧ Shift is also better. It has also limitations though.

About the EtP pattern what is the EtP pattern?

We would’ve also liked to have had the button overwrite or erase the user’s recent browser history, but we can’t do that either. (And for good reason!)

Why redirect the user to BBC weather?

As civil servants, we didn’t want to link to a news service as that could lead to claims of political bias.
BBC Weather’s homepage is a content-rich page. Users have a reason to be looking at it and to be looking for an extended period of time.