why was a third on the earth is burn in reverlation 8?

2 possibilities in my opinion:

a meteor strike,

or a nuclear war triggered by the antichrist, as he tries to maintain control over the nations during the second half of his reign.

****
in response to one of the other answers given: it should go without saying that the scripture is referring to a third of the LAND AREA, not a third of the total surface area. it isn't necessary to read something into it that isn't there, just to argue with it.

The nuclear war will start out between the Asian capitalist , such as India , and the Muslims of that region with the help of the Chinese Communists ; burning up that part of the world's vegetation . Easily killing off a third of the world's population .

The fourth trumpet sounded and the sun was smitten, God causes this as one of the seven last plague, so the first trumpet seems to have an effect similar to the fourth trumpet,
It could be meteorite hit the sun and explodes, showering the earth with fire, the suns heat being cut off from the earth would freeze clouds into ice, blood from the people.
The earth is dry land above the water, Gen 1: 10

This event happens during The seven year tribulation on Earth. Christians will not be present for these Seven years. Only nonbelievers will suffer the consequences of Judgment of The Lord.

CB

Three is a number associated with God and His judgement and separation.

All through the Scripture you will find this, three days, and a third for destruction.

These are judgements therefore brought by God on sin and they have been since the time they were given.


… and the third part – this apportionment is significant and is used to show judgement and loss and the cross cutting off the flesh. The number three is strongly associated with God’s judgement through Scripture. It is always the third day that significant matters of judgement are brought to pass.

Abraham saw the place of sacrifice on the third day, Laban discovered Jacob’s flight the third day, Jacob split his caravan into three to face Esau, Simeon and Levi slew the circumcised on the third day, Pharaoh lifted the butler’s head the third day, Joseph held one of his brothers hostage as prisoner the third day, the third month after leaving Egypt Israel came into the wilderness of Sinai, God came down to Mount Sinai the third day, the flesh of the vow or voluntary offering must not be eaten the third day, a third part for oil and wine offerings, must purify the third day as well as the seventh after touching a corpse or killing a person, Egyptians could enter the congregation of the Lord the third generation, the third year is the year of tithing after entering the land, the third day Israel discovered they had made a league with the inhabitants of the land because they did not consult the Lord, Israel went against Benjamin on the third day, the Lord called Samuel three times, Israel rebelled against Rehoboam the third day, Ezekiel divided his hair and beard into three parts for judgement, and many other examples the most immediate is Christ’s crucifixion as one of three, and being in the tomb three days and three nights,

Eze 5:1-4 And thou, son of man, take thee a sharp knife, take thee a barber's razor, and cause it to pass upon thine head and upon thy beard: then take thee balances to weigh, and divide the hair. Thou shalt burn with fire a third part in the midst of the city, when the days of the siege are fulfilled: and thou shalt take a third part, and smite about it with a knife: and a third part thou shalt scatter in the wind; and I will draw out a sword after them. Thou shalt also take thereof a few in number, and bind them in thy skirts. Then take of them again, and cast them into the midst of the fire, and burn them in the fire; for thereof shall a fire come forth into all the house of Israel.

Rev 1:1 john is told the vision is "signified" meaning given in symbols and meaning. some of them we are told directly and the others are taken from the OT of which the Christians in the first century understood.
Ezekiel cuts off his hair and beard and seperates them into 3 areas and does an action to each group.
cuts up one group = die by the sword
burns up one group = die by famine
releases one group into the air = taken to the nations

also he ties a small group into his robe belt = faithful ones protected (by captivity actually)

this happened in the 500-600s BC

so they understand these symbols of what is going to happen to Jerusalem again.

this is NOT a declaration against the full world but just talking about what is going to happen in the first century with this judgment against Jerusalem and then the roman empire.

@Chicago Bob - anytime you hear someone talking about a 7 year trib you should auto know they are full of crap. they have no understanding of prophecy. they are just repeating out what they hear from others.

It was the 5th 3rd (5/3) of the aganxt wort dribln whonk.

70% of the surface area of the globe is covered by water. Obviously the book was written by someone who wasn't aware of what the globe looked like. Mathematically all continents would be burned to the ground if this were true and 3% of the ocean. Since there would be no human life left--well--kinda shows you how absurd the story is, doesn't it.

By the way it was a trumpet blown, not a turnip lol