Climate change accelerates the extinction of species(global warming)
The current high rate of species loss has led scientists to claim that we are experiencing the 'sixth great extinction'. The rate of species loss is similar to that of the other five previous ones that have occurred in the history of the Earth, such as the one that wiped out the dinosaurs 65 million years ago. The hand of man is behind this mass extinction. Edward O. Wilson, professor emeritus at Harvard University and father of the concept of biodiversity, combines the causes of this sixth extinction in the now-famous word HIPPO (hippopotamus), the acronym for loss of habitats, invasive species, pollution, overpopulation, and excessive capture of wild species.
But fauna, plant species and many other organisms that attract less attention also have a major challenge in climate change. Biologists have been trying for years to assess how and at what speed a rise in global temperature will affect biodiversity. The problem is that predictions of the percentage of species that will become extinct as a result of climate change vary widely depending on the species considered , the geographic region or the factors considered.
A researcher from the Department of Ecology and Evolutionary Biology at the University of Connecticut (USA), Mark Urban, has evaluated 131 important scientific works published on the matter and has included known factors that affect biodiversity to try to obtain a conclusion about how climate change will affect species in a future affected by climate change . And the conclusions, published in the journal 'Science', are shocking.
The first relevant piece of data presented by Urban is that about 16% of the world's species will disappear if greenhouse gas emissions continue to grow as they have done now. In other words, one of every six species that we know of, we will not be able to show them except in photos to our grandchildren. In addition, the regions that will be most affected by rising temperatures are South America, Australia and New Zealand.
"Actually, the study also draws attention to regions like Asia, where there are few published scientific studies and it is difficult to draw a conclusion. But the work indicates that the range could be less than 10% or close to 30% of species extinct ", explains Mario Díaz, head of the Department of Biogeography and Global Change of the National Museum of Natural Sciences of the CSIC. "But the most striking thing is not so much the percentage of species that will disappear, but how clear the work reflects that the extinction of species will grow exponentially with the increase in temperature", says the Spanish researcher.
In reality, the resulting percentages in the study should not be taken at face value. As Mario Díaz explains, the models include many factors that can vary and cause a result to oscillate from 14% of lost species to 7% or 21%. What is truly relevant about Urban's work is the direct link between temperature rise and species extinction . And, even more, that the increase in the rate of disappearance grows disproportionately - exponentially, not linearly - with each increase of one degree in temperature.
According to Mark Urban, the current extinction rate is 2.8%. If the objectives to which the international community aspires and which have been recognized at the United Nations Climate Summits of a maximum global temperature increase of 2ºC were met, the species disappeared on a global scale would be 5.2%. But if the increase were to be 3ºC, the extinction rate would go to 8.5%. And in the event that it reached 4.3ºC - a scenario that would be reached with the current rate of emissions growth - disappearances would reach 16% of the species.
"We must not wait for more data to act against climate change, ideally by reducing greenhouse gas emissions, " writes Janneke Hille Ris Lambers, of the University of Washington, in an article accompanying Urban's work. "If we don't, it is clear that soon we will be able to directly observe the impacts of climate change on biodiversity," https://www.extinction.live/