How could that happen if a bunch of literal major physical catastrophes are going on all over the world?
The 7 years begin when the prince that shall come is perceived by the Jews as their long awaited messiah.
The false prophet anoints the prince that shall come as the King of Israel thought-to-be messiah, making the person the Antichrist.
In that role as the King of Israel, the Antichrist will confirm the Mt. Sinai covenant for the 7 year period Moses required in Deuteronomy 31:9-13.
So the 7 years begin. No catastrophes going on in the world, except maybe a small muslim uprising to the Jews rebuilding their temple on the temple mount - and destroying the Dome of the Rock and Al Asqua mosque.
"Peace and safety" mode in the world for around three years.
Then totally unexpected, the Antichrist commits the transgression of desolation act of Daniel 8:13 described in 2Thessaloinans2:4 of going into the temple, sitting, claiming to have achieved God-hood. Revealing himself as the man of sin, and not the Jewish messiah after all. End of his stage of being the Antichrist. The Jews will renounce him as their King of Israel.
War breaks out. In Ezekiel 28:1-10, God has strangers come against the revealed man of sin and has him assassinated, mortally wounded.
In Isaiah 14:18-20, God in total disdain for the person, a Jew, who destroys his own people and land, casts him out of the grave, i.e. brings him back to life.
In Revelation 13, he is the mortally wounded but healed head. Becoming the beast-king. Which the false prophet has an image made of the beast-king and placed on the temple mount as the abomination of desolation.
And the great tribulation begins. During which, the catastrophes that you speak of will take place.