Some form of epidemic - virus, bacteria, etc.

After years of searching, we finally find the WMDs in Iraq.

Possibly war between Pakistan and India, they hate each other so much.

But, the Korean war returning after 60 years is looking much more likely unfortunately

Peace between Israel and Palestine

The hottest summer on record for Europe! (Forest fires from Spain to Norway, wtf?)

2035, the year there is no summer sea ice in the Arctic Ocean!

Earthquake destroys Los Angeles and Tokyo, at the same time!

Coastal cities across the world submerged after series of storm surges and tsunamis, 2.5 billion climate refugees

The first human clone

Communist revolution in Russia again

The dissolution of the European Union, due to the economic crisis ----)
Crash of the United States economy ---) The end

Lol it funny but true. (jk) 

Almost everything you guys have stated would be pretty huge news. I personally would say USA attacking Iran and Russia and China defending Iran thus causing WW3 would be the worst news possible in this world of ours. Other than a gigantic meteor crashing into Earth wiping out all life on the planet or Yellowstone National Park super volcano erupting killing hundreds of millions and choking out the sun for hundreds of years while ash and dust and sulfur spew into the atmosphere making it non breathable thus resulting in the deaths of billions of other people.

The Meaning of Life

I went outside.

The council of the united interstellar civilization grants the humans the status as 'possible candidate for future delevopment into a minor civilization'.

Super powers

The biggest possible news, that would have a worldwide effect?

Someone nukes someone else, World War 3 starts.