The Year the World Crossed the 1.5°C Threshold, What Happens Now in 2025?
Awa B. | 16 June 2025
Summary
2024 was the hottest year on record, with global temperatures averaging 1.6°C above pre-industrial levels marking the first full year of the Paris Agreement’s 1.5°C threshold being surpassed.
Climate impacts are intensifying in 2025, including extreme weather, food insecurity, and rising displacement, particularly affecting developing countries.
Political and financial responses remain uneven, though pressure is growing on fossil fuel companies, insurers, and governments to act.
Long-term risks remain significant, with a realistic possibility of approaching 2°C of warming by the 2030s if emissions are not rapidly reduced.
In 2024, the world experienced its hottest year on record, with global average temperatures reaching 1.6°C above pre-industrial levels. This marked the first time the world exceeded the 1.5°C warming threshold for an entire calendar year; this surpassed the limit set by the 2015 Paris Agreement, an internationally agreed-upon target to avoid severe climate impacts.
As of mid-2025, the consequences of this warming have become increasingly evident with intensified heat waves across Southern Europe and Asia, unprecedented coral reef bleaching, and worsening food insecurity, especially in vulnerable regions.
However, the World Meteorological Organisation (WMO) stresses that exceeding 1.5°C in a single year does not invalidate the long-term goal of the Paris Agreement. Climate scientists clarified that the Paris target refers specifically to long-term, human-induced warming averaged over decades, intentionally smoothing out short-term variations caused by natural events like El Niño or volcanic activity.
A significant contributor to 2024’s record temperatures was unprecedented ocean warming. An international study published in Advances in Atmospheric Sciences found that ocean temperatures reached their highest levels ever recorded from the surface down to 2,000 meters. This warming occurred despite the transition from El Niño to neutral conditions, indicating that the primary driver was the continued accumulation of greenhouse gases in the atmosphere.
Although the long-term Paris Agreement goal remains technically achievable, the severe impacts seen in 2024 showcase a critical gap between political commitments and actual reductions in CO₂ emissions. Current emissions remain high, and the damage from recent warming episodes could be irreversible.
Implications
Environmental:
In 2025, irreversible damage has intensified significantly: Antarctic Sea ice remains at record lows, coral reefs face widespread die-offs, and prolonged droughts severely disrupt agriculture and freshwater access in regions such as Southeast Asia and Sub-Saharan Africa.
Extreme weather events including a severe India–Pakistan heatwave, major flooding in Buenos Aires, Argentina, and Botswana, as well as widespread wildfires across the United States and South Korea
Economic:
Insurance companies in the UK and EU are scaling back coverage in high-risk regions, raising costs for homeowners and businesses.
Flood Re, the UK’s government-backed scheme, received a third of its total claims during the severe 2023/24 storms but only covers homes built before 2009, leaving around five million privately rented properties excluded.
Rising flood risks have led insurers to raise premiums, increase excesses up to £2,500 for some and deny coverage for high-risk properties. Without insurance, many owners cannot get financing. Insurers cite climate change, urban development, and poor drainage as key causes.
Crop yields are falling in climate-sensitive regions such as India, North Africa, and the U.S. Midwest, contributing to rising global food prices.
In Nigeria and similar economies, drought and flooding are crippling agriculture and driving food insecurity.
Political:
Even as climate disasters become more severe, progress on climate action has slowed in some countries. In the United States the election of Donald Trump, whose administration cut back many environmental protections, showed how easily climate policies can be weakened in a divided political climate. These changes led to large protests and growing public unrest.
On Earth Day 2025, thousands of Americans joined protests across the country to speak out against the administration’s environmental policies. Many of these demonstrations also raised concerns about social justice, especially how environmental damage often hurts low-income and marginalised communities the most.
Security:
Internal displacement from climate-driven disasters reached 83.4m in 2024, with major displacement in countries like Bangladesh, Honduras, and Nigeria. Cross-border climate migration is rising sharply, placing additional pressure on border regions in South Asia, Central America, and parts of Sub-Saharan Africa in 2025.
Social and Humanitarian:
The WMO's finding that over 90% of climate-related deaths occurred in developing countries shows that the human toll of climate change is not equally shared. This highlights the inequality in who suffers most, linking climate change directly to humanitarian crises, especially in vulnerable regions. Cyclones, floods, droughts, and heat waves often force people from their homes, destroy healthcare and education systems, and increase poverty which are core social disruptions.
The Indigenous peoples, rural communities, and low-income populations are hit hardest, not only physically but also socially through loss of land, cultural heritage, and access to necessities. These effects tie directly into climate justice discussions, where marginalised groups face the most harm.
Chris LeBoutillier/Unsplash
Forecast
Short-term (Now - 3 months)
There is a realistic possibility that increased public pressure will be directed at fossil fuel companies.
It is likely that there will be an increase in climate activism, litigation, and shareholder pressure in 2025, forcing firms to disclose their climate risks and defend their decarbonization timelines.
It is likely that some insurance companies are beginning to reassess the level of risk they assume in flood-prone and coastal areas. In certain regions, this is leading to higher insurance costs or limited coverage. These changes are happening gradually and vary depending on the location.
There is a realistic possibility that investors pull back from high-risk zones and trigger divestment in coastal and flood-prone areas.
Medium-term (3-12 months)
There is a realistic possibility that there will be a sharp rise in heatwaves, floods and other natural disasters.
There is a possibility of an expansion of carbon removal investments. Carbon removal technologies like direct air capture and reforestation are receiving growing interest, especially from EU institutions and private investors.
It is likely that more governments are integrating climate resilience into their infrastructure, health, and agriculture plans. This shift is expected to be reinforced at upcoming global forums like COP31 and G20, where adaptation funding and implementation will be high on the agenda.
Regional bodies such as the African Union and ASEAN are also pushing for coordinated climate action strategies.
Long-term (>1 year)
Breaching 2°C by 2040 becomes unlikely. However, there is a likely chance that if current global emissions trends continue without significant reduction by 2027, the 2°C threshold could be approached. This raises long-term risks for vulnerable ecosystems and communities.
There is a likely chance that continued warming is expected to gradually affect ecosystems such as coral reefs and polar regions. Although the changes are gradual, their long-term effects could become more difficult to undo after the early 2030s.
There is a realistic possibility that climate-related displacement is expected to rise gradually, especially due to drought, coastal erosion, and urban flooding. While most migration will remain internal, some regions may see increased cross-border movement.
