**5.1 Physical planet Earth's environment**

According to the core accretion theory, planet Earth formed around 4.54 billion years ago (approximately one-third the age of the universe) by accretion from the solar nebula [38].

Planet Earth has faced climate change throughout its long history. The current climate change has multiple negative impacts on the physical planet Earth's environment. It affects the frequency and severity of extreme events and natural disasters [1, 4, 6–13, 19].
