In 20 years, according to the main forecasting models, with current policies, we will reach the threshold of 2°C years of global warming. The effects of global warming will not be evenly distributed. A study reconstructs the regional variations of the main variables, including thermal stress, precipitation, relative humidity, fire risk, and wind speed. Amazonia and the Mediterranean basin are the two areas that overall will suffer more from the impact of climate change
NASA study published in Earth’s Future
Without new and more ambitious climate policies, we will reach 2 degrees of global warming during the 1940s. In 2041, in the worst-emitting scenario, and 2044, in the low-emitting scenario. The climate impact of at +2°C, However, will not be distributed evenly across the Planet. What will be the local and regional effects of this drastic change in the Earth’s climate system?
This was investigated by the NASA Ames Research Center in a study, recently published in Earth’s Future, in which it details changes for 6 climatic variables – including air temperature, rainfall variations and relative humidity, and the speed of winds – and two indicators of climate impact – thermal stress and weather conditions conducive to the triggering of fires – at the global and regional level.
The impact of a climate at +2 ºC in the Amazon
From this map of the world at +2°C, one of the most critical areas that emerges is the future of the Amazon. It is in the largest rainforest in the world that some of the most extreme variations linked to the impact of a +2 ºC climate are concentrated.
The Amazon basin is the region where the number of days with a high thermal stress index will increase more than ever, but also where the probability of fires increases more and where it will rain less than current levels (-98 mm/year), leading to record decreases in relative humidity (-1.7%). And probably energy supply problems, given the importance of hydropower in the area.
The climate of the future in Europe and the Mediterranean
One of the most significant and less considered impacts of a 2-degree warmer climate than the pre-industrial one in Europe is the reliance on wind energy to decarbonize the continent’s electrical mix. Northern Europe is focusing heavily on wind energy, including offshore energy, to reduce the role of oil and gas. However, exceeding the upper limit of the Paris Agreement will decrease the speed of winds throughout the region.
“The northernmost extratropical area shows a decreasing wind speed, while an increasing model is observable in most of the southern hemisphere,” reads the NASA study. “It is noteworthy a sharp decrease in wind speed over Central North America (-0.13 m/s) and East (-0.11 m/s), Northern Europe (-0.12 m/s) and Tibet (-0.11 m/s)”.
For the Mediterranean area, however, the study confirms the long-term trends and the connected criticalities already highlighted in recent years by a series of studies on the subject. The area of the Mare Nostrum, and therefore Italy, will become a hotspot of climate change not so much for the relative increase in air temperature, which is expected around two degrees and with little variation depending on the emissive scenarios that we will take, while for other regions, such as Greenland, a warmer world 2°C results in temperatures close to +4 ºC.
On the contrary, the significant drops in precipitation and relative humidity – second only to those that will touch the Amazon and Central America – will characterize the region. That will intertwine with the increase in thermal stress, at levels among the highest in the world. For Italy, the most significant change is expected mainly in the Centre-North and on the larger islands. The risk of fire will also be much higher.
