Hannah is one of many authors who published an article predicting that between 15% and 37% of species are at risk of extinction due to climate change caused by human greenhouse gas emissions.
Hannah received his Doctorate in Environmental Science and Engineering from the University of California, Los Angeles in June 1985.
Since 2004, he has also been working as a visiting researcher and adjunct professor at the Bren School of Environmental Science & Management at the University of California, Santa Barbara.
Thus, habitat connectivity is needed so that plants and animals will be able to move to find suitable climatic conditions[3] Finally, Hannah supports lowering greenhouse gas emissions.
[1] The study was done by computer simulations and based on the ecological law of the species-area curve, which amounts to the bigger the piece of livable land, the more species it harbors.
If international policy action results in climate change starting to level-off, it would reduce the number of extinctions projected by the study.
Likewise, some believe that just because living area shrinks, it is not necessarily indicative of the exact number of species that will go extinct.