In order to achieve this, four experiments were performed...
Therefor (without the added e), according to Oxford Living Dictionary this means:
'For that object or purpose.'
This as opposed to therefore, which means (according to Oxford Living Dictionary)
'For that reason; consequently.'
This article by Grammarly explains the difference between the two words:
"Therefor means “for it,” or “for that.” It’s one of those words like “therein,” “thereafter,” and “thereof” that you rarely use in everyday speech but should be aware of."
They also provide examples, one of which is:
"I took back the dress I bought, and the shop gave me a reimbursement therefor."
Suppose we have this sentence using in order to achieve that (this replaced by that):
We needed to show he was drunk, and we used an alcoholtest in order to achieve that.
We could write:
We needed to show he was drunk, and we used an alcoholtest therefor.
You could ask, what did you need the alcoholtest for? You could answer that by saying: for showing he was drunk or In order to achieve showing he was drunk.
In your example this would require some pretext:
We want to show the state of the climate, in order to achieve this, four experiments were performed.
We want to show the state of the climate, four experiments were performed therefor.
So, four experiments were performed.
so TFD adv
- Afterward; then: