The World Meteorological Organization and other U.N. climate agencies said this week that 2024 is likely to be the hottest year on record, driven by a strong El Nino and continuing greenhouse gas emissions. Officials warned that temperature records set in recent years are being broken again, increasing the frequency of dangerous heat events and exacerbating droughts, wildfires and flooding around the world.

Data compiled from national meteorological services and global observing systems show early 2024 monthly averages running higher than the same months in 2023, the previous warmest year on record. Experts said the pattern is consistent with model forecasts and with long-term warming caused by human emissions of carbon dioxide and other greenhouse gases.

Background and history of the issue

Global temperatures have risen steadily since the late 19th century, with the past decade among the warmest in the instrumental record. Scientists attribute the trend primarily to the accumulation of greenhouse gases from fossil fuel combustion, deforestation and industrial processes.

The World Meteorological Organization, the United Nations Environment Programme and national climate centers maintain global monitoring networks that track temperatures, greenhouse gas concentrations and related indicators. Those systems showed that 2023 was the warmest year to date, and the El Nino event that developed in late 2023 has contributed to further warming in early 2024.

The Intergovernmental Panel on Climate Change has warned that continued emissions would lead to more frequent and severe climate extremes. Analysts say the current run of record-setting years underscores the reality of those projections and the limits of adaptation without stronger emissions cuts.

Key facts, figures and stakeholders

Key indicators cited by agencies include rising global surface temperatures, increasing atmospheric concentrations of carbon dioxide and more extreme weather events.

• Temperature trends: Early 2024 monthly averages have exceeded the corresponding months in 2023, pushing the year toward a likely new record.
• Greenhouse gases: Atmospheric CO2 concentrations remain elevated, near levels above 410 parts per million recorded in recent years, maintaining their long-term upward trajectory.
• El Nino influence: A strong El Nino has amplified global warming signals by shifting ocean and atmospheric circulation patterns, contributing to higher global surface temperatures.
• Impacts felt worldwide: Heatwaves, drought and intensified rainfall events have been reported in regions including parts of Asia, Africa, the Americas and Europe, with economic and humanitarian consequences.

Stakeholders in the unfolding climate situation include national governments, subnational authorities, humanitarian agencies, farmers and businesses. Vulnerable populations in low-lying coastal zones and drought-prone inland regions face heightened exposure to physical risks.

Reactions

U.N. and scientific officials urged rapid policy responses. Agency spokespeople noted that El Nino makes the short-term outlook worse but stressed that the underlying cause is long-term emissions.

Analysts say the announcement is likely to intensify calls for accelerated mitigation by major emitters and for more funding for adaptation in low-income countries. Climate advocates pointed to the report as evidence that international commitments are not yet sufficient to avoid increasingly severe impacts.

Government responses have varied. Some national leaders reiterated commitments to reduce emissions and accelerate renewable energy deployment. Other officials emphasized the need for emergency preparedness and humanitarian assistance to help communities cope with immediate impacts.

Broader implications and what happens next

If 2024 becomes the warmest year on record, policymakers will face mounting pressure to deliver stronger mitigation measures under the U.N. Framework Convention on Climate Change. Experts said several areas will be in focus:

1. Accelerating reductions in carbon dioxide and methane emissions through policy and technological shifts.
2. Scaling up climate adaptation finance to help vulnerable countries strengthen resilience.
3. Improving early warning systems and disaster response to reduce loss of life and economic disruption.
4. Advancing research on regional impacts to better target agricultural, water and infrastructure planning.

Economists and risk analysts warned that repeated record years increase the probability of compound disasters that can overwhelm local response capacity and create cascading economic damage. Insurance markets are already adjusting premiums and coverage in many exposed regions, while investors are increasingly factoring climate risk into asset valuations.

Scientists stressed the role of continuous observation networks and improved modeling to refine seasonal and longer-term projections. They say those tools can help decision makers prepare for likely near-term extremes while charting pathways to lower global emissions over the coming decades.

Frequently Asked Questions

Why is 2024 likely to be the hottest year on record?

Early-month temperature averages in 2024 have been higher than the same months in the previous warmest year, 2023. A strong El Nino event is amplifying natural variability, and long-term warming from greenhouse gas emissions is raising the baseline temperature, together increasing the likelihood of a new record.

How does El Nino affect global temperatures?

El Nino shifts ocean and atmospheric circulation, releasing heat stored in the tropical Pacific into the atmosphere and altering weather patterns globally. This natural cycle typically boosts global average temperatures for the year or two it is active, on top of the warming trend from human emissions.

Are recent records proof that human-caused climate change is happening?

Scientists say the trend in record high temperatures, alongside rising greenhouse gas concentrations, is consistent with human-caused climate change. Weather and climate extremes are influenced by natural variability, but the long-term warming trend is driven primarily by emissions of carbon dioxide and other greenhouse gases.

Which regions are most affected by the warming so far?

Heatwaves and droughts have been notable in parts of Asia, Africa and the Americas, while heavy rainfall and flooding have affected other regions. Low-lying coastal areas face rising sea levels as a chronic risk, and communities dependent on seasonal rainfall are particularly vulnerable to disruptions.

What can governments and communities do to prepare?

Officials can invest in early warning systems, strengthen emergency response, secure water and food supplies, and upgrade infrastructure to withstand heat and extreme precipitation. Longer term, reducing emissions and investing in resilience are central to limiting future risks.

Will a single hot year change global climate policy?

A single year rarely changes policy on its own, but a string of record years adds urgency to international negotiations and domestic policy debates. Repeated extremes can increase public and political support for stronger mitigation and adaptation measures.

How reliable are the temperature records and forecasts?

Global temperature records are compiled from extensive networks of land and ocean observations and undergo quality control and analysis by multiple independent agencies. Seasonal forecasts that incorporate ocean-atmosphere conditions like El Nino are well established and help provide probabilistic outlooks for the year.

As the year unfolds, agencies will continue to update their analyses and provide more detailed regional outlooks. For now, the consensus from climate monitors is that 2024 is on track to set a new global temperature record, reinforcing concerns about the accelerating impacts of a warming world.