But, warming is just one among many consequences of a global crisis.

Population: we are more and more

Between 1700 and 2003, the world human population multiplied tenfold, from about 600 to 6,300 million. From 2050, growth will level off to reach around 12 billion in 2100. Europe and North America have slowed their population growth. However, the rest of the world representing the largest part of the population is growing more.

The current level of the planet's population places enormous stress on its sustainability due to the demand for water, food and energy, along with considerable losses in biodiversity.

Fresh water: the next source of conflict

Global population growth and economic development will weigh even more heavily than climate change on the relationship between availability and demand for freshwater. Access to freshwater is already at risk for 80% of the world's population.

Much of the world will face substantial challenges in securing water supplies. This will require a significant effort in infrastructure and technology, but also in water distribution and pricing policies. When the water supply becomes limiting, it will lead to the reduction of economic activities, to infrastructure giving up, and even conflicts around hydrographic basins.

Energy: we will continue to burn fossil fuels

Between 2015 and 2050, global CO₂ emissions, mainly related to energy, will increase by 6%, from 33 to 35 Gt, depending on current and projected policies. These emissions would need to fall to 9.7 Gt in 2050 to meet the 2°C maximum increase target of the Paris Agreement.

The most optimistic views suggest that renewable energies can provide two thirds of the global energy demand. That requires multiplying by six the current rate of these growth sources. The EU goal on climate neutrality by 2050 is shared with the United States; even China intends to strive to that reach that goal in 2060.

However, data from the International Energy Agency on oil consumption for the 2019-2026 period still forecast a 4.4% increase in world demand for crude oil. The lower use of fossil fuels in some OECD (Organisation for Economic Co-operation and Development) countries will be largely offset by higher consumption in developing countries. In short, the owners of fossil fuels are not going to stop taking advantage of their resources.

Food production and consumption

Striking a balance between agricultural intensification, the fight against hunger and biodiversity conservation, while reducing negative environmental impacts, is one of the greatest challenges humanity is facing.

In principle, the farmland and grasslands of planet earth can produce the food needed to provide for the entire human population. However, in 2019 almost 690 million people (8.9% of the population) suffered from malnutrition. These figures have been getting worse for several years.

In addition, the global food system has significant impacts on the environment through water extraction, pollution, change in land use, and biodiversity loss. Food production contributes to global warming through greenhouse gas emissions, although to a much lesser extent than the fossil fuels use. At the global level, an increase in emissions from food production is expected, especially due to the African continent’s demographic and economic growth, which will double its contribution in 2030.

Biodiversity loss

The biodiversity loss derives from changes in land use by agriculture, from changes in the climate due to the use of fossil fuels, as well as from other effects associated with human being’s actions. The consequences of this loss affect the ecosystems functioning and the services they provide.

Mediterranean climate and grassland ecosystems will experience the largest proportional change, due to the substantial influence of all drivers of biodiversity loss. Despite international efforts, biodiversity conservation goals is not being achieved yet.

Solutions to a global crisis

We are not facing a climate crisis, but rather a global crisis derived from the overexploitation of resources on a planet of finite dimensions. We focus our attention on global warming, biodiversity loss, and other collateral consequences of resource overexploitation. But, we don't want to see the elephant in the room: unsustainable population growth that we need to stabilize or even reverse.

In London in 1798, Thomas R. Malthus wrote, "the perpetual tendency of the human race to grow beyond the means of subsistence is one of the animated nature’s general laws, which we cannot expect to change."

In its call from science, the scientific world advocated in 2019 to mitigate and address the changing reality through transforming the way we govern, manage, feed ourselves and use materials and energy. In a recent update, it proposes to tackle three fronts: implement a global carbon price, phase out and eventually ban fossil fuels, create strategic climate reserves to protect and restore natural carbon sinks and biodiversity.

Some of these messages fit with the green commitment of Europe, the continent that suffers the most from the scarcity of raw materials, where there is greater social pressure in favor of green policies, and which maintains a certain leadership in alternative energies and technologies necessary to mitigate global climate change. But, that vision is utopian, since no society is really willing to give up its growth and well-being for the good of the planet.

The solution, if it comes at all, will not come from a sudden global agreement that reverses current trends. Only science could provide technological solutions to control the climate, increase water availability, maximize food production and conserve what remains of biodiversity. However, it may already be too late.

See, Población, agua, biodiversidad, energía y alimentación: los pilares de una crisis global