By the end of the century, 2 billion people will live in places with temperatures beyond the threshold of “dangerous heat”

An international group of researchers on the initiative of the Global Systems Institute of the English University of Exeter has studied, on the basis of a world population estimated at 9.5 billion individuals in 2100, the consequences of a 2.7°C increase in temperature by the end of the century (i.e. in the period between 2080 and 2100), publishing their results in the journal Nature Sustainability. This average temperature rise corresponds to what should be achieved globally if we stick to the policies currently implemented in the fight against global warming. Well, the researchers conclude that, under these conditions, 22 percent of the world’s population, or over 2 billion people, will find themselves living in places where average temperatures will reach above the “dangerous heat” threshold, set at 29th annual average The countries with the largest number of human beings exposed to this condition will be India (600 million), Nigeria (300 million) and Indonesia (100 million).In an even more pessimistic scenario, at +3 .6°C or even +4.4°C, half of the world’s population would be at risk.

Now, if average warming could be limited to +1.5°, i.e. if the target set in Paris in 2015 were reached, these effects could be prevented; but since it is now a rather widespread belief in the scientific community that this objective is unattainable, it is good to make a further consideration, following the reasoning of the authors of the study. In short, for every tenth of a degree of average temperature rise saved on our planet, about 140 million people will be saved; thus, for example, limiting global warming to 2°C by the end of the century (the least ambitious goal of the Paris agreements), 980 million people would be saved compared to the 2.7°C in the study.

Now, I would like to make some considerations with the reader. First of all, it is obvious that, since we are dealing with forecasts of future conditions, we can only use mathematical models to try to define what could happen, knowing that these can fail with a well-defined probability; However, here it does not count to know exactly when we will reach the indicated temperatures, but instead it is important to consider what would happen when that point were to be reached. This part of the authors’ model is the most interesting, because, beyond the quantitative estimates, it allows us to make some important considerations.

First of all, as we might expect, the populations that are least responsible today in terms of per capita emissions will be those on average exposed to the worst consequences in terms of rising temperatures, living in areas of the world that are physically more exposed in the event of a global increase. This simple datum reveals a further profound injustice, which goes hand in hand with those documented for centuries in our world of exploitation and asymmetrical wealth. More precisely, as the authors point out, if their maths are right, the lifetime emissions of 3.5 average global citizens today, or just 1.2 US citizens, expose a future person to heat dangerous; but this future heat-exposed person will live in places where emissions today are about half the global average. Even if the math doesn’t turn out to be so accurate, the overall trend remains the same, whichever model is taken into consideration: that is, climate inequity is a fact that does not change if the value of the emission parameters and their effect on the climate change, because it only depends on the distribution of emissions and the global population.

Secondly, it should be noted that the damage considered by the authors, i.e. only that directly linked to extreme heat, does not consider other harmful consequences of climate change: meteorological events with higher and more frequent energy and rising seas are an example, considered in other studies. This variegated set of other negative effects will be more evenly distributed, but the resources to defend ourselves will once again be more concentrated in the hands of the major polluters (because consumption and emissions are today largely correlated to economic strength and rate of development).

Finally, although, selfishly, we can hope to be better equipped to deal with climate change in countries like ours, there is a general consideration that suggests greater foresight in implementing global policies to prevent emissions, and not just to protect against climatic extremes: climate migrations, which have already begun today, could lead to the displacement of hundreds of millions of people from areas where survival will become almost impossible, with consequences in terms of international and internal tensions that can be easily guessed, which will be nothing more than the product of the climatic inequity mentioned above. Some will also be able to take refuge in the usual world of fairy tales, telling themselves that bad catastrophists exist and that the models don’t work, just as happened with Covid-19; others will then be able to count on being dead before trouble strikes (even if their children and grandchildren will be very much alive). Honestly, as always, I prefer to listen to scientists, and act accordingly: where acting, at this moment, means first of all, as far as I’m concerned, studying the solutions that research indicates, to communicate them and form public opinion; and secondly, to act individually as responsibly as possible, perhaps following the indications of the United Nations and downloading the appropriate app to measure the collective impact of anyone who does the same with me.