"grave impact on" is a correct and usable phrase in written English.
You could use it to describe the serious effect that something has on something else. For example, "The global pandemic has had a grave impact on the economy."
If our libraries closed it would leave a lot of people stranded, and have a grave impact on my life".
Climate change, which Trump has denied and dismissed, has already had a grave impact on the world's poorest people.
"Fertilisers and pesticides have played an important role in enhancing productivity but in certain areas improper use has had a grave impact on the environment," he said.
Sheik Saud said in his statement today that oil prices had fallen over the last two years to below $10 a barrel and that this had had a grave impact on the economies of oil exporters.
Jo Glanville, director of English PEN, said: "The coup posed a serious threat to the Turkish state, but the closing down of publishers, alongside the mass sackings, detentions, arrests and allegations of torture, will have a grave impact on democracy.
The declassified portion of the report obtained by the Guardian says only that DIA "assesses with high confidence that the information compromise by a former NSA contractor [redacted] and will have a GRAVE impact on US national defense".
The judge said the allegations were "very grave", impacting on Cruddas's personal honour and integrity, and received "maximum possible publicity".
A limitation on wood does not have grave impacts on the economic performance of the system, eliminating the wood gasification, increasing the utilisation of grass resources to 81%and76%6% for grassland and fields, respectively, and lowering the revenue to 92% of the optimal value.
In doing so, we are altering the global nitrogen cycle, causing possible grave impacts on biodiversity, global warming, water quality, human health, and even the rate of population growth in developing nations.
Sparse networks, those with low node density, are the most interesting, as they cannot make use of traditional adhoc routing algorithms, and the most challenging, since decisions carry a graver impact on global performance.
If Jennifer owns a steel factory, it is for her to decide (in her own interest) whether to close it or to keep the plant operating, even though a decision to close may have the gravest impact on her employees and on the prosperity of the local community.
