Last year the global average temperature rose to 1.15°C above its preindustrial (1850-1900) level. For its part, France is struggling to maintain a trajectory that will keep its own rise below 2.5-3.0°C (temperatures rise faster on land). Should it, as the government suggested after a public consultation this summer, be preparing for a global rise of 3°C – and 4°C in France?

Climate projections indicate this scenario is not compatible with the survival of complex lifeforms on earth: droughts and heatwaves are already increasing the frequency of uncontrollable wildfires and massive crop failures. Given the inertia of climate change (long-term effects are not amenable to short-term actions), such extreme weather events will inevitably become more frequent and intense, and without a drastic cut in greenhouse gas emissions, scientists warn that global warming could drive the planet across a threshold, ‘raising the temperature further to activate other tipping elements in a domino-like cascade’ (1).

Accepting this scenario at global level would be to risk irreversible changes such as our tropical rainforests turning into savannahs, no longer able to function as carbon sinks. The polar ice caps would then melt even faster, accelerating sea level rise and weakening the major ocean currents that temper the climate of many parts of the world. Likely repercussions for European countries include epidemics of diseases hitherto unseen in Europe, and human migrations on a scale impossible to cope with.

The need to slow emissions

The UN’s 2015 Paris climate accord raised hopes of significantly slowing greenhouse gas emissions. But few countries have met their commitments, which were already inadequate for achieving the overall goal. Some companies have massively stepped up investment in fossil fuel exploration and extraction, and the development of new toxic chemicals – a total of around $2.2tr since 2016. Others – notably China Energy Investment Group (coal), TotalEnergies and Saudi Aramco (oil) – plan to continue exploiting fossil fuels until 2030, through projects known as ‘carbon bombs’ because of their potential for making the climate unliveable. Most big international banks, including France’s BNP Paribas, Crédit Agricole and Société Générale, have helped finance these projects and are making huge profits on them, providing backing for a mass crime against humanity and the environment.

Rather than paying lip service to climate adaptation (futile once global warming reaches a certain threshold), governments should be prioritising efforts to slow greenhouse gas emissions and other harmful activities, and taking action against the companies responsible. There are still many things that could help stop the descent into irreversible catastrophe:

– We should require businesses to show on their balance sheets the impact of their activities on human health and natural resources. In many cases, the dividends they pay shareholders come from harmful activities; they total more than $5tr a year according to IMF estimates (2) and should be sanctioned.

– Public finances, in other words tax and subsidy systems, should be restructured to force companies to cease harmful activities and contribute to sustainable adaptation.

– Banks that continue to finance the destruction of human health and natural resources should be required to pay the kind of penalties applied to those who fund criminal activities (drug trafficking, terrorism etc).

– Inequality must be eradicated: the world’s richest 10% are responsible for 60% of greenhouse gas emissions. Since they can easily cope with, or circumvent, indirect fiscal pressure, it’s important to attack the source of their privilege – their income, assets and influence. Although the ‘exceptional’ and ‘temporary’ tax rates recommended in policy thinktank France Stratégie’s report (3) are low, they were condemned by the economy, finance and industry minister. Was this short-sightedness or collusion?

– Funds need to be transferred from wealthy countries, which bear historical responsibility for global warming, to less developed countries, which are often its first victims (4). US special presidential envoy for climate John Kerry estimates $3-4tr a year will be required; a recent study puts the figure at around $6tr a year (5).

Poorer countries need help

Denouncing the idea that adaptation to 4°C of warming is possible does not mean abandoning all efforts to prepare for the consequences of current global warming projections, remembering that this will not be possible for those of modest means unless there is a significant redistribution of income and assets.

Not all solutions are equally good. Cereal farmers in Nebraska, US, have developed an irrigation system that adjusts the volume of water to the needs of the crop (measured using soil moisture probes) and enables them to cut groundwater pumping by 20%, while growers in France’s Poitou-Charentes region continue to irrigate indiscriminately, with groundwater stored in artificial open-air megabasins.

Few countries have met their commitments to the UN’s 2015 Paris climate accord which were inadequate even then

But while the Nebraska farmers have achieved considerable water savings, they still don’t see that their agroindustrial methods are unsustainable. In their approach, the soil is merely a vehicle for fertilisers and biocides. This leads to devastating pollution, not only of the soil, but also of inland waterways, coastal waters and even the atmosphere (through emissions of nitrous oxide (N2O), a greenhouse gas 280 times more damaging than carbon dioxide). It’s unsustainable in the long term.

Millions of farmers in India, already facing severe climate change, are coming to the end of what the ‘green revolution’, based on the selection of more efficient crop varieties and over-use of chemical inputs, had to offer. In the southern state of Andhra Pradesh, with government support, they are turning to agroecology. A number of different crops are grown in parallel or in rotation to maintain soil fertility and act as a barrier to harmful organisms. And trees are planted among the crops, helping to manage water and capturing atmospheric nitrogen for their own growth and that of the surrounding crops. Meanwhile, European economists and agronomists have shown that the agroecological approach could feed the entire population of the EU decently, provided consumer tastes and habits also changed (6).

Protecting coastal areas

Intelligent adaptation also has a place in major civil engineering projects. With a significant rise in sea level now unavoidable, we need to protect coastal areas. Rather than building dykes ever higher, the Netherlands is creating defensive ecosystems. Salt marshes, willow ‘mangroves’ and oyster and mussel beds diffuse a significant part of the energy from storms and absorb much of the sediment they carry. Local populations, too, need to be involved in adapting to threats from the sea: Rotterdam has extensive public warning networks and has established training and mutual assistance programmes.

River catchment areas can amplify or slow flooding caused by extreme rainfall, depending on how they are managed. For smaller applications – a street, garden or small urban park – the Royal Botanic Gardens in the UK have developed ponds whose edges are planted with drought-resistant vegetation and their bottoms with plants that capture excess water and release it relatively slowly. This is just one example of how natural resource engineering can provide solutions, even if their individual impact may seem modest.

In major cities, which in future will be home to a growing proportion of the world’s population, living conditions will deteriorate significantly, especially during heatwaves. In 2007 France’s Grenelle environment forum identified improving the energy efficiency of buildings as a priority. This is a slow and complicated process unless governments provide landlords and tenants with technical, administrative and financial support, yet many solutions already exist, ranging from installing infrared light filters to incorporating vegetation into the fabric of buildings, which can reduce indoor temperatures by as much as 8-10°C.

There needs to be a reversal of the current trend in which (generally young) protesters are labelled as environmental extremists and subjected to violence, or even imprisonment, for wanting to halt the march to oblivion. Meanwhile those responsible for the destruction escape criticism and sometimes even receive awards.

The key to climate adaptation is social change and people agreeing to make their fair share of the effort. What can we hope to achieve? Or rather, what can those born this century hope for? Provided we immediately stop destroying the necessary conditions for life on earth (which will require considerable imagination), they can hope for a future. Even then, it may not be a comfortable one.