Disclaimer: Copyright infringement not intended.

Context:

The year 2024 has now been confirmed to have breached the 1.5-degree Celsius global warming threshold, becoming the first calendar year to do so.

Details

According to scientists at the Copernicus Climate Change Service (C3S), 2024 was the hottest year since global temperature tracking began in 1850.

The average global temperature was 15.1 degrees Celsius -- 0.72 degrees above the 1991-2020 average and 0.12 degrees higher than that in 2023, the previous record-holder.

What does exceed 1.5°C mean and why is it significant?

• The 1.5°C mark referred to in the 2015 Paris Agreement is an arbitrary threshold indicating severe climate impacts with increasing temperature. It does not mean a sudden change, but it points to the worsening effects of the climate.
• 2024 became the first calendar year to exceed the 1.5°C warming threshold, with the global annual average temperature 1.6°C above pre-industrial levels (1850–1900).
• Context of the Paris Agreement: The5°C target refers to long-term trends over decades, not individual years. Therefore, this violation does not yet mean that the Paris Agreement has been violated.

Why did 2024 become the hottest year ever?

Contributing factors:

• The global average temperature was 1.5°C above pre-industrial levels for the first time in 2024.
• It averaged 15.1 °C, which was 0.72 °C above the 1991–2020 baseline and 0.12 °C above the 2023 baseline.
• 2024 also saw 1.6°C above pre-industrial estimates (1850–1900 levels).
• Sea Surface Temperature (SST): Annual SST in extrapolar oceans reached a record 20.87°C, beating the 1991–2020 average by 0.51°C. SST levels from January to June 2024 were the highest for this period, while July to December were second only to 2023.
• El Niño Effect: A major El Niño event that began in June 2023 contributed to the warming and its effects lasted until 2024.
• Exceeding 1.5°C for one year does not mean that the threshold has been exceeded permanently.
• Experts warn that if this trend continues for a decade or more, it would mark a permanent crossing of this critical threshold.

No single cause: ECMWF notes that the warming was the result of a combination of factors and further analysis is needed.

How do 2023 and 2024 compare to previous years?

Extremely warm years:

• 2023: 1.45°C above pre-industrial levels.
• 2024: 1.6°C above pre-industrial levels, breaking the previous record.

Monthly trends: Every month since July 2023, except July 2024, has been more than 1.5 °C warmer than the pre-industrial average.

Does this breach mean that the 1.5°C target is unattainable?

• A one-year breach does not mean the Paris Agreement's goal is unattainable. Emphasis is placed on trends over several decades.
• Outlook: With global warming rates above 0.2°C per decade, exceeding the 1.5°C target by the 2030s is very likely.

What are the long-term consequences of a breach in 2024?

• Global emissions: Emissions are still rising and the 2030 emission reduction targets are unlikely to be met. This increases the likelihood that the 1.5°C breach will become the norm.
• Projections: Annual temperatures could reach 1.9°C above pre-industrial levels before 2028, according to the WMO. There is a 50% chance that the five-year average will exceed 1.5°C by 2028.

What does 2025 and beyond look like?

• Forecast for 2025: It is not expected to surpass 2024 as the warmest year. It is likely to remain between 1.1°C and 1.4°C above pre-industrial levels, consistent with the past decade.
• Long-term trends: The UK Met Office predicts that 2025 could be the third warmest year on record, after 2024 and 2023.

About the Copernicus Climate Change Service (C3S)

The Copernicus Climate Change Service (C3S) is a key part of the European Union's Copernicus program dedicated to providing comprehensive climate information to support adaptation and mitigation efforts.

• Established: 2014
• Administered by: European Center for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Commission. Provide authoritative information on past, present and future climate conditions in Europe and the world. Analyze historical climate data to track changes and trends.
• Provide seasonal forecasts and future climate projections under different greenhouse gas emission scenarios. Offer users worldwide free and open access to climate data, tools and information.

READ ABOUT

Climate Change 2024: Record Heat and Urgent Action

Copernicus Climate Centre Service

UN Environmental Summits 2024: Failures & Challenges

Source:

INDIAN EXPRESS

DECCANHERALD