According to the latest report from the Intergovernmental Panel on Climate Change (IPCC), climate change is widespread and rapidly intensifying. United Nations Secretary-General Antonio Guteress called the report a “code red for humanity, where the alarm bells are deafening and the evidence irrefutable.”
Among the changes noted by scientists throughout the climate system, namely in the atmosphere, glaciers, oceans and land, many are unprecedented and considered irreversible for centuries or millennia, such as sea level rise.
The internationally agreed threshold of 1.5° above pre-industrial levels of global warming is dangerously close and could even be reached in the short term(we can reach it in upcoming 20 years). The only way to avoid exceeding this threshold is to urgently step up our efforts by pursuing the most ambitious path.
The report, prepared by 234 scientists from 66 countries, shows that the influence of human activity has impacted climate at an unprecedented rate for at least the last 2,000 years.
Co2 concentrations in 2019 were at their highest in at least 2 million years, while methane and nitrous oxide concentrations were higher than at any time in the past 800,000 years.
Meanwhile, average sea levels have risen faster since 1900 than in any previous century in the last 3,000 years.
Scientists point out that evidence has strengthened between climate changes observed in extreme natural events and their attribution to human influence. In addition, they add that many changes are closely related to increased global warming, including increases in the frequency and intensity of extreme events.
Scientists predict that climate change will increase in all regions in the coming decades; for 1.5°C of global warming, heat waves with longer hot seasons and shorter cold seasons will increase; for 2°C, extreme heat events are likely to reach critical tolerance thresholds for agriculture and health.
And it’s not just a temperature issue. The water cycle is heavily involved, bringing more intense rainfall and associated flooding, as well as more intense droughts in many regions.
Coastal areas will see continued sea level rise throughout the 21st century, contributing to more frequent and severe flooding and coastal erosion. Even more amplified will be the effects of climate change for cities, including increasing heat and flooding.
IPCC experts say there is still time to limit climate change. Through strong and sustained reductions in emissions of carbon dioxide and other greenhouse gases, air quality could rapidly improve and in 20 to 30 years global temperatures could stabilize.
The UN chief, in a detailed section of the report, said the solutions are clear: “inclusive and green economies, prosperity, cleaner air and better health for all if we respond to this crisis with solidarity and courage.”
To contain the phenomenon it will be essential to achieve the goal of zero net Co2 emissions, as well as other greenhouse gases, thus aiming to stabilize the climate.