Climate Change and Its Impacts on Biodiversity in Mexico

Abstract

During the last 150 years, the increase in the average temperature of the atmosphere and oceans has been documented due to the increase in the concentration of greenhouse gases produced by the burning of fossil fuels, deforestation, excess production and reduced capacity to capture pollution. The consequences have been radical changes in the distribution of ecosystems and species, rise in sea level, disappearance of glaciers and corals, unpredictable and extreme climates such as droughts and storms. Climate change affects all organisms on the planet, many of them are already responding to this new dynamic through changes in their distribution and migrations. All these factors are the product of human activities and their social, economic and political causes. The effects of human activities, which were previously small-scale, have turned into large-scale events, affecting the climate of the entire planet. Climate change has become one of the main threats to biodiversity. In Mexico, a large number of endemic species of highly restricted distribution are susceptible to be affected by the indicated factors. Aims: The objective of this study is to present a set of regional projections of temperature, rainfall, humidity and drought index for Mexico under the IPCC AR6 climate change scenarios, and to evaluate their impact on biodiversity in Mexico by the end of the century. Methodology and Results: Regional models for Mexico show temperature increases between 0.5 to 5°C, while % precipitation will range from -20.3 to 13.5% depending on the scenario and period of analysis. The low soil moisture, vegetation changes and drought indices show that the North, West and Bajío areas presented reductions in precipitation and temperature increase that caused soil moisture deficit, water stress, presence of scarce vegetation and semi-permanent meteorological drought. Under these scenarios, it is expected that the entire country will be subjected to moderate to extremely strong droughts that will last and worsen between now and the end of the century. The results of the scenario projections and forecasts made by the IPCC show that the effects on biodiversity associated with climate change have been manifested for several decades in Mexico and are expected to worsen by the end of the century, increasing the number of threatened and endangered species. Based on the probable temperatures by the end of the century (from 0.5 to 5°C) it is estimated that the risk of extinction ranges from 3 to 48% in terrestrial ecosystems, in ocean and coastal ecosystems the risk of biodiversity loss will go from moderate to very high; and for endemic species it is estimated that the risk of extinction is very high with the possibility of increase by more than ten times. Conclusion: Thus, the vulnerability of biodiversity in Mexico is high to very high, which puts a very high number of species and ecosystems at risk.