Climate emergency: time to act

On Monday, August 10, the report AR6 Climate Change 2021: The Physical Science Basis was published, the first of the three parts that will make up the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).

This document, developed by 234 experts from 66 countries, updates and reduces the level of uncertainty in the forecasts for the evolution of global warming in the coming decades. For the preparation of the document, more than 15,000 articles and academic references published so far on this topic have been reviewed, with the aim of developing a detailed synthesis on the effects that warming has had on the physical environment, as well as five possible warming scenarios based on greenhouse gas emissions (GHG) emitted between now and 2100.

Source: AR6 Climate Change 2021: The Physical Science Basis

Each warming scenario implies a series of consequences on different indicators, such as temperature, precipitation, extreme weather events, rising sea levels or the loss of the frozen surface of the Arctic.

“According to the report, which highlights a climate emergency against which it is time to act, there is a direct relationship between the increase in temperature and extreme weather events.

Expectations are not very flattering. In an intermediate GHG emission scenario, temperatures would rise from 2.1 to 3.5 ºC by the end of this century but could reach 5.7 ºC in the worst-case scenario. Taking this evolution into account, by 2060 the 2 ºC warming will have been exceeded. In fact, in the last fifty years, the temperature on the Earth’s surface has risen faster than in any other similar period in the last 2,000 years.

But what does the increase in temperature imply? According to this report, there is a direct relationship between the increase in temperature and the proliferation of extreme meteorological phenomena, such as torrential rains, cyclones, droughts or the decrease in Arctic ice, among others.

Likewise, the report argues that it is unequivocal that human influence has been an accelerating element, increasing the chances of such extreme events materializing.

“A rise in sea level by the end of the century is not excluded, which implies an impact on terrestrial and marine ecosystems and millions of people living in coastal areas.

The most devastating aspect is that many of the changes observed in the climate system are unprecedented and a large number of their consequences, such as thawing or rising sea levels, will be irreversible for thousands of years. In the latter case, an increase of around one meter by the end of this century cannot be excluded, in the worst-case scenario. This, apart from the tremendous impact on a multitude of terrestrial and marine ecosystems, puts many millions of people who live in coastal areas at risk and who would be forced to migrate to inland areas.

However, although the outlook is dark, the situation is not irreversible, at least for the moment. According to the most optimistic emissions scenario, it is still possible to ensure that the temperature increase does not exceed 1.5 ºC by the end of the century. But, for this, it is necessary to generate rapid, sustained and large-scale reductions of GHG emissions. The evolution in the most favorable scenario implies a reduction of emissions of 40% by 2030 and reaching neutrality of emissions by the middle of the century. Although these reductions would take approximately three decades to have an effect on temperature, the benefits to air quality would be seen in no time.

The task ahead is twofold, since we must reduce emissions and adapt to changes, both those that the planet is suffering and those that derive from the solutions we must take to heal the wounds.

It is clear that this will only be achieved with strong political decisions, severe changes in the production model, effective technological developments and, above all, with climate awareness. We must all understand that passivity will condemn the planet to a path of no return. We must be clear that we are facing the greatest challenge that humanity has faced. We know what the goal is and how to get there, so it’s time to act.

Pablo Collazo,responsible for Environmental Sustainability at Abengoa.