So after a genetic survey of Amazon tree species it has been determined that many of the species have survived for a surprisingly long time in the region (over 8 million years in some cases). Previously it had been believed that most tree species originated in the cold Quaternary Period (in which we are now), beginning some 2.6 million years ago.
In fact, of the 12 species surveyed, seven have been around for at least 5.6 million years and three for more than 8 million years.
This means that many of the common amazon tree species were around during previous periods of high temperatures induced by previous instances of rapid CO2 induced climate change such as the early Pliocene (3.6 million years ago to 5 million years ago) which was equivalent to the IPCC's moderate carbon emission scenario. During the highest emission IPCC scenario, temperatures will be equivalent to what they were during the Miocene (5.3 to 11.5 million years ago).
The implications are clear: Amazon tree species can survive extreme temperatures up to and including those predicted for the most extreme emissions scenario.
So no tree dieoff then.
No comments:
Post a Comment