Climate on the brink: Earth nears critical warming threshold
Climate organizations are warning that last year was the hottest on record. The global average temperature was higher than the average temperatures at the end of the 19th century before humans began the mass burning of fossil fuels. What does this mean for us?
The Earth is inevitably approaching a breach of the global warming limit of 1.5 degrees Celsius, as indicated by two significant studies published on February 10 in "Nature Climate Change" by European and Canadian scientists. According to these analyses, our planet's climate is entering a new, terrifying phase. What are the risks we face?
The threshold that crossing will initiate irreversible changes on Earth
Climate organizations worldwide agree that last year was the hottest on record. The average global temperature in 2024 was about 1.6 degrees Celsius higher than the average temperatures at the end of the 19th century before large-scale fossil fuel burning began.
Under the Paris Agreement of 2015, we are aiming to reduce greenhouse gas emissions to limit the temperature rise to no more than 1.5 degrees Celsius. However, in 2024, the average temperature on Earth temporarily exceeded this limit. This does not yet mean that the threshold set in Paris has been breached, as the agreement's targets are measured over decades, not through short-term increases in temperatures above 1.5 degrees Celsius.
Even a month or a year can mean crossing a critical threshold
New studies have taken a different approach. Analysis of historical climate data indicates that recent very warm years may signal a long-term breach of the permissible warming threshold. The outcome of these studies is alarming: the record-breaking year 2024 suggests that the Earth is indeed crossing the 1.5-degree Celsius threshold, beyond which catastrophic changes in natural systems may occur.
According to scientists, the variability in global temperature from year to year means that climate experts do not consider a single year exceeding 1.5 degrees Celsius as a failure of the Paris Agreement. The research team, both from Europe and Canada, suggests that even just a month or a year with warming of about 1.5 degrees Celsius can mean a long-term crossing of this critical threshold for the Earth.
Only zero CO2 emissions will halt global warming
Studies conducted in Europe and Canada separately analyzed whether a year with warming above 1.5 degrees Celsius is a signal of crossing the agreement threshold. Both studies utilized climate model observations and simulations, with the European study analyzing historical warming trends and the Canadian study examining monthly data.
Both analyses show that even in the case of strict emission reductions, the Earth will most likely exceed the 1.5-degree Celsius threshold. Worse, greenhouse gas emissions continue to rise, indicating that we are not heading in the right direction, and science shows that we must achieve zero CO2 emissions to stop global warming.
What awaits us if we cross the critical threshold?
If the Earth has indeed already crossed the critical threshold, we will need to achieve "negative emissions", meaning we will need to remove more greenhouse gases from the atmosphere than we emit, which is a colossal challenge. The impacts of climate change are already being felt worldwide, and the situation will worsen for future generations. Unique ecosystems are already suffering from rising temperatures, and sea levels threaten coastlines.
Fires, floods, and extreme weather conditions, especially heat waves, are becoming more frequent and severe, which strains nature, society, and the economy. Despite this, as the study authors believe, progress is visible, especially in renewable electricity generation and reducing fossil fuel consumption.
Scientific analyses show how far we are from effectively combating climate change. They indicate that we must urgently adapt to global warming. According to the analysis authors, wealthier countries should support poorer ones, which are the most vulnerable to the effects of climate change.
