Biodiversity and Environmental Impact from Climate Change: Causes and Consequences

The Intergovernmental Panel on Climate Change reports that current global warming is unprecedented in the past 2000 years, and atmospheric CO2 levels are the highest in at least 2 million years. Such profound alteration of the global climate is exacerbating the effect of direct human pressure on biodiversity. Climate change affects human activities and, consequently, land-use change, for example forcing the shifting of crops to newly suitable areas (e.g., at higher latitudes and higher altitudes). Land-use change acts synergistically with climate change in altering the distribution and abundance of wildlife, with cascading effects on ecosystems, for example in terms of pest species and pathogens arrival. Thus, the combined effects of climate and land-use change pose high risk to global biodiversity, with a high projected increase in global extinction rates which already largely surpass the rates registered from the fossil record. The projected decline of biodiversity compromises ecosystem functioning and, consequently, the provision of Nature’s Contributions to People (NCP)—the contributions of nature to people’s quality of life. However, several studies show that bold climate policies (compliant with the Paris Agreement) can largely reduce such risks. Reversing biodiversity decline is still possible, combining international abatement of carbon emissions with actions that limit habitat loss and degradation, such as the establishment of protected areas and the definition of sustainable land-use policies. Analyzing scenarios of future environmental change can guide the definition of strategies to safeguard biodiversity and NCP, but this requires a paradigm shift from the “business-as-usual” approach, built on the intense use of fossil fuel and natural resources, to a greener socio-economic growth which aims at achieving ambitious biodiversity targets.