Human well-being and the health of the planet are at risk from the threats posed by warming, greenhouse gas emissions and insufficient efforts to contain them. Many of the effects of climate change, attributed “unequivocally” to human activities, are irreversible. For this reason, it is necessary to reduce them as a priority: to prevent greater damage.
In this sense, “a substantial reduction in the general use of fossil fuels”, responsible for these gases, is key. This is what the scientists of the UN’s Intergovernmental Panel on Climate Change (IPCC) say in a summary document (37 pages) of the sixth complete assessment of climate change studies.
The pace and scale of climate action plans are “insufficient” to tackle climate change, scientists say.
In 2018 the IPCC highlighted the unprecedented scale of the challenge posed by containing warming to 1.5°C. Five years later, this challenge is even greater due to the continued increase in greenhouse gases.
More than a century of burning fossil fuels, as well as unsustainable use of energy and land have led to a warming of 1.1 °C above pre-industrial levels. The result is more frequent and intense extreme climate events, which have caused increasingly dangerous impacts on nature and people in all regions of the world.
The report detects an “unequivocal” human influence on the warming of the atmosphere, the seas and on land. Sea level rise (result of melting ice) is accelerating: from 1.3 mm per year between 1901 and 1971 to 1.9 mm between 1971 and 2006, and up to 3.7 mm from 2006 to 2018. This human influence has been seen since at least 1971. “Evidence for observed extreme changes such as heat waves, heavy rainfall, droughts and tropical cyclones and in particular their attribution to the influence human, has strengthened even more” compared to the fifth cycle of the IPCC (2014), they add.
The growing number of extreme weather and climate events, with serious impacts on many communities (Africa, Asia, South America, small islands…), have exposed millions of people to acute food insecurity. Between 2010 and 2020, human mortality caused by floods, droughts and storms was fifteen times higher in highly vulnerable regions compared to low vulnerability regions. Climate change has caused substantial damage and increasingly irreversible losses to ecosystems.
The report, approved during a one-week session in Interlaken (Switzerland), highlights the losses and damages we are already experiencing and will continue in the future (with food and water security crisis…). They will especially affect the most vulnerable people and ecosystems. “Climate justice is crucial because those who have contributed least to climate change are disproportionately affected,” said Aditi Mukherji, one of the 93 authors.
Containing warming to 1.5°C above pre-industrial levels (or even slowing it down to 2°C) means “taking immediate actions that involve deep, rapid and sustained reductions in greenhouse gas emissions decade”. However, climate action plans announced by governments (assuming they are implemented) lead to a warming of 2.8º C by 2100.
Stopping warming at 1.5º C requires greenhouse gas reductions of 43% by 2030 compared to 2019; and if you don’t want to cross the 2º C threshold, it would be necessary to reduce them by 21% with a path destined to approach climate neutrality towards 2050.
The warming scenarios that the climate models draw for the end of the century (2081-2100) indicate temperature rises of 1.4º C, 2.7º C and 4.4º C according to the scenarios (low emissions, medium emissions or high emissions). Hazards and risks expected in the short term include an increase in heat-related human mortality and morbidity from food-, water- and vector-borne diseases.
The IPCC emphasizes that some future changes are inevitable and irreversible, although they can be limited with sustained reductions in global greenhouse gas emissions. In the worst case scenario (high emissions), the sea level could rise between 0.63 and 1.01 meters by 2100. The IPCC advocates a comprehensive response to climate change.
For example: access to energy and clean technologies and active mobility reduce emissions and improve people’s health (electrification, walking, cycling). It’s the same with diet changes to achieve a healthier diet.
