The damage climate change has done and will do to marine ecosystems may not be irreversible, but it will take thousands of years to recover.

According to the AFP, authors of a study published in the journal Proceedings of the National Academy of Sciences analyzed a sediment core sample off the coast of Calif. dating back between 3,400 and 16,100 years.

It was previously held that such marine ecosystems would need hundreds of years to rehabilitate from the ill effects of climate change. The researchers said that estimate was too low.

"These past events show us how sensitive ecosystems are to changes in Earth's climate - it commits us to thousands of years of recovery," study lead author Sarah Moffit, a marine ecology scientist from the University of California - Davis Bodega Marine Laboratory and Coastal and Marine Sciences Institute, said in a press release. "It shows us what we're doing now is a long-term shift - there's not a recovery we have to look forward to in my lifetime or my grandchildren's lifetime. It's a gritty reality we need to face as scientists and people who care about the natural world and who make decisions about the natural world."

The researchers analyzed more than 5,000 fossil samples of seafloor invertebrates. Combined with the sediment core, the fossils provided an idea of what happened to these ecosystems the last time there was a major deglaciation.

"After the initial sampling at sea, I took the entire core, which was about 30 feet long," Moffitt said. "I cut it up like a cake, and I sampled the whole thing. Because of that, I had the whole record."