https://www.coinwarz.com/difficulty-charts/ethereum-difficulty-chartjump from 1,800T to 2,200T
ttps://steemit.com/ethereum/@joshbreslauer/ethereum-metropolis-upgrade-in-late-september
In addition, the so-called Difficulty-Bomb is actually delayed and will be part of the 2nd Hardfork of Metropolis.
The Difficulty Bomb should cause an expanding difficulty in ethereum's mining.
It is an intermediate step for the gradual replacement from proof-of-work to proof-of-stake.
This is the so called Ethereum "Ice Age".
But for the next Metropolis HF in September 2017 this should be delayed to the 2nd part and replaced by a simple Block Reward reducement from 5 to 3 ether per block.
https://www.reddit.com/r/EtherMining/comments/6t56a0/important_information_from_todays_ethereum_dev/For those of you wondering what the real world impact of these bombs going off is, they are significantly increasing the amount of time it takes to mine blocks. Before one of the first bombs went off in mid May, it took on average about 14.5 secs to mine one block which contained 5 ETH. If you look at this chart
https://etherscan.io/chart/blocktime you can see the exact times each subsequent bomb has gone off to the point we are at now were it is taking about 21 secs to mine 1 block of ETH. With the current implementation of Ice Age, this is what block times will look like over the coming bomb drops:
August 25th - 25 seconds
September 24th - 32 seconds
October 31st - 41 seconds
