Rome must prepare for climate change scenarios that may increase the impacts and, therefore, the risk to which the city, its economy and social fabric are exposed. At the international level, climate scenarios have been developed, by the Intergovernmental Panel on Climate Change (IPCC) of the United Nations, which consider various projections of increases in global emissions and temperatures that will depend on the measures countries are able to implement to stay within the temperature increase targets of the Paris Agreement. While the scenarios in the projection of what may happen at the end of the century have significant margins of uncertainty, all cities that are working on adaptation consider scenarios to 2050 as the reference for identifying adaptation measures.
The results of the projections
Roma Capitale has asked CMCC (Euro-Mediterranean Center on Climate Change) to prepare for the Climate Adaptation Strategy an assessment of climate variations in the period between 2036 and 2065. The elaborations considered the three specific scenarios developed by the IPCC:
- RCP8.5 “High-emission,
- RCP4.5 “Strong mitigation,
- RCP2.6 “Aggressive mitigation.”.
The acronyms associated with the individual scenarios, such as RCP8.5 "High Emissions," RCP4.5 "Strong Mitigation," and RCP2.6 "Aggressive Mitigation," are simplifications commonly used by the various available documentations (e.g., Climate-ADAPT) to describe the different projections of GHG emissions in the context of climate change. It is important to note that these acronyms are simplifications used to facilitate understanding of the different emissions scenarios and do not necessarily represent exact descriptions of what will happen in the future.
The elaboration estimated for the three different scenarios what might happen, and in all simulations they share the same unequivocal trend of increasing average temperatures, duration of warm spells, thermal discomfort index, and reduction of frost days.
Climate science highlights the uncertainty with respect to the accuracy of local-level estimates that are too far forward in time because they are linked to temperature increases in different areas of the world and to the nonlinearity of the consequences of global warming processes in individual urban areas. But what is indisputable is that in Rome, albeit with differences related to emission scenarios, there will be an increase in the frequency and intensity of atmospheric phenomena that already currently cause significant impacts on the city, as well as an increase in periods of intense heat and so-called tropical nights.
