With regard to the public perception of the climate crisis, the communication faces a situation similar to that surrounding the Covid pandemic 20: the accumulation of measurements at confirming the warming seems insufficient to discredit a minority of skeptics with the power to cause much damage.
At the beginning of every year, reports from scientific and multilateral institutions appear stating that the temperature of the Earth’s atmosphere is far above the historical average. The headlines create a sense of déjà-vu: 2021 was the sixth warmest year on record since 1880.
Tens of thousands of thermometers in weather stations, automated ocean buoys and ships indicate that the atmosphere is 1.5°C above the century average 20. If the parameter is 1880, when the planetary temperature sampling became reliable, the measured increment is 1.1°C.
Two dozen of satellites confirm observations made on the surface. Supercomputers from Nasa and NOaa (American space, oceans and atmosphere agencies) calculate the contribution of each factor to warming –changes in orbit, solar activity, ash from volcanoes, etc.– and conclude: only human activity explains the magnitude of the phenomenon.
Last year it tied with 2018 in the sixth position. The last eight years rank as the hottest eight. The concentration of CO2 (the main greenhouse gas) in the atmosphere has been rising steadily since the 1990s 1880. The simple repetition takes away the novelty character of the information, when it should raise alarm.
It is the same effect of the summer rains in Southeast Brazil. As they return every year to wreak havoc, they engender the conviction that these are cyclical occurrences that fall within the range of natural climate variability.
This is a dangerous misconception. The constant return of floods, landslides, deaths, severe droughts and forest fires masks, for the public, the fact that rainy periods become rainier and dry periods drier. With more energy added to the atmospheric system, extreme events accumulate.
Abstract demonstrations offered by the best science, which confirm the predictions of climatology, take time to be mirrored in the daily experience of populations. When the statistics become robust enough to convince the common people, it may be too late.
Against the urgent awareness of the climate threat work ideologies of denial. The opportunism of pseudoscientists is put at their service.
As the troops of Jair Bolsonaro in the government militate against indigenous and quilombola rights, rural landowners addicted to cheap land, land grabbing and expansionist livestock are predisposed to buy in the same package climate change denialism (not to mention vaccines).
Large farmers pay to attend lectures by a retired meteorology professor who denies data from NASA satellites and computers. His arguments are as successful as Brazilian flags, on the gates of properties, and public health attacks by the president and his entourage of charlatans, in medicine.
Maybe some of the soybean farmers who are losing their harvest in the drought ravaging the south of the country change their minds, just as some anti-vaccine activists can surrender in the face of the death by Covid of a family member. Perhaps.
If and when they change their minds, however, it may be harmless. Against the coronavirus there are masks, distancing, vaccines and the possibility of adapting them to fight new strains, but with the climate crisis there are others 500.
Half of the CO2 emitted today from burning fossil fuels and forests remains more than a century in the atmosphere, blocking the dissipation of solar energy back into space. The half-life of methane produced in the digestion of cattle and in flooded rice fields is over ten years.
The UN climate change convention was adopted in Rio-92. Since then, carbon emissions have only increased, although it is essential to cut them in half over the next ten years and eliminate them by 2050 to meet the goal of containing warming by 1.5°C, as decided six years ago in the Paris Agreement.
The retrospect of nearly three decades of international negotiations on the climate crisis makes one fear the worst. And the resilience of denialist ideas in Brazil proves the failure of institutions, academia and the press ahead, to guide the national debate with facts and evidence.