UN scientists warn 70% chance global temperatures exceed 1.5°C in next 5 years

UN Scientists Warn of 70% Chance Global Temperatures Will Exceed 1.5°C in Next Five Years

In a stark new warning, United Nations scientists have estimated there is now a 70% probability that global average temperatures will temporarily surpass 1.5 degrees Celsius above pre-industrial levels within the next five years. This latest assessment signals an escalating urgency in international efforts to address climate change, as the world approaches the key threshold targeted by the Paris Agreement.

The 1.5°C Threshold: A Critical Benchmark

The 1.5°C mark holds significant importance in climate science and policy. It is considered a crucial “guardrail” that, if crossed, risks exposing human societies and natural ecosystems to increasingly severe impacts, including more frequent heatwaves, droughts, extreme weather events, sea-level rise, and loss of biodiversity. The threshold was codified in the 2015 Paris Agreement, with nearly every nation pledging efforts to keep global temperature rise “well below” 2°C and to pursue efforts to limit it to 1.5°C above pre-industrial (mid-19th century) figures.

UN Scientists’ New Findings

Drawing on the latest global climate models and observational data, the United Nations’ climate science panel evaluated the growing likelihood of the world exceeding this benchmark. Based on current emissions trajectories and ongoing global warming trends, their new report places the probability of temporarily breaching 1.5°C at 70% within the period from now until 2029.

This updated outlook represents a notable increase from previous estimates. Notably, while passing 1.5°C would likely be temporary on a year-to-year average, scientists emphasize that each year above this level will have cumulative impacts and may pave the way for higher, more prolonged exceedance in future decades if greenhouse gas emissions are not rapidly curbed.

What “Exceedance” Means

The scientists clarify that “exceedance” refers to a temporary annual average global temperature above 1.5°C, not that the target will be permanently surpassed immediately. There remains a window to stabilize global temperatures over longer time frames. Nonetheless, the rising odds underscore the current inadequacy of current climate policies and actions.

Acceleration Driven by Human Activity

The main driver behind this rapid warming is the continued and growing emission of greenhouse gases, primarily carbon dioxide and methane, arising from the burning of fossil fuels, deforestation, and other human activities. Despite international pledges for stronger climate action, recent years have seen insufficient progress in reducing global emissions.

Potential Consequences of Surpassing 1.5°C

Exceeding the 1.5°C threshold, even temporarily, is expected to amplify climate risks. According to climate scientists, this could result in more intense heatwaves, heavier rainfall, longer and more severe droughts, and higher incidences of wildfires. Vulnerable populations, particularly in low-lying and developing regions, would face heightened threats to livelihoods, health, and infrastructure.

Global Response and Next Steps

The UN’s new warning comes ahead of several key international climate meetings, where negotiators are under increasing pressure to strengthen national commitments to reduce emissions, invest in adaptation, and support vulnerable communities.

Experts stress that limiting the frequency and duration of temperature exceedance hinges on immediate and large-scale cuts to greenhouse gas emissions. Accelerated deployment of renewable energy, increased energy efficiency, reforestation, and technological innovation are among the recommended measures.

Conclusion

With the probability of surpassing 1.5°C in the next five years now at 70%, the UN scientists’ report marks a pivotal reminder of the urgent need for sweeping climate action. The world stands at a decisive moment, facing the challenge of averting the worst consequences of climate change as outlined in the Paris Agreement.

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