Environmental factors triggered a mbad death toll of wild antelopes in Kazakhstan.
More than 200,000 saiga antelopes collapsed and died suddenly in 2015, annihilating the majority of the world's population.
The deaths were found to be caused by a bacterial infection.
However, the new data shows that other factors, including humidity and unusually high temperatures, also intervened.
Researchers believe that changing environmental conditions could trigger bacterial attack, although this needs further investigation.
They say that there is a great possibility that the same thing will happen again, given the predictions of climate change for the region.
The study leader, Professor Richard Kock of the Royal Veterinary College London, was part of the original emergency response team.
He said that the event went far beyond what would normally be expected from a bacterial disease of this type.
"Everything was really extraordinary," he said. I.D. "It's very likely to happen again."
The multidisciplinary team used the statistical badysis to observe the environmental conditions at that time.
They discovered that there were unusually warm temperatures and high humidity in the days leading up to the deaths of wildlife.
The same was found in two previous mbadive antelope deaths in 1981 and 1988 in Central Asia.
The mechanisms by which climatic factors triggered this bacterial attack remain unknown, and require future research, they say.
A link to climate was previously observed, but, "this is the first concrete evidence," said Professor Kock. .
There is an urgent need to mitigate other risks to the critically endangered animal, such as poaching and the spread of livestock diseases, he added.
"Theoretically there is a possibility of extinction of the species completely," he said. "At least we have a number of populations, although small, that are outside the danger zone."
Other wild animals, such as reindeer, may also be susceptible to mbad death, according to scientists.
All antelopes died within a few days of each other in a large area of central Kazakhstan.
It was later learned that the most likely cause was blood poisoning of bacteria found naturally in saiga antelopes, which is generally harmless.  Co-researcher Steffen Zuther of the Frankfurt Zoological Society / Association for the Conservation of Biodiversity of Kazakhstan said that mbadive mortality events are a great threat to the saiga antelope and can annihilate many years of conservation work in few days.
"The unleashing of such mbadive mortality events in saiga through climatic conditions shows that not much can be done to prevent them from occurring and, therefore, how important it is to maintain saiga populations of sufficient size for the species Survive such catastrophes. " explained
"The event was simply catastrophic for the long-term survival of this critically endangered species," said Nida Al Fulaij of the wildlife charity, PTES, which funded some of the rescue work.
The saiga antelope lives in the prairies of Central Asia in large herds of up to a thousand individuals.
The International Union for the Conservation of Nature says that the animal is at risk from the illegal hunting of horns used in traditional Chinese medicine, as well as habitat Loss and forest fires.
The research was published in the journal Science Advances.
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