March 2025 stands out as one of the hottest months ever recorded worldwide, with an average temperature of 14.06 ° C, or 1.6 ° C above pre-industrial levels.
This figure places the month in the second row of the hottest March in the history of climatic surveys, just after March 2016. It is part of a persistent warming trend, marked by 20 months out of 21 above the symbolic threshold of +1.5 ° C, fixed by the Paris Agreement.
An increasingly clear climate alert
The recurring overcoming of this threshold, although measured over monthly periods, confirms a structural trend and not a temporary phenomenon. Despite the end of the El Niño phenomenon, which generally contributes to temporary global warming, global temperatures remain abnormally high. According to experts, this persistence is mainly explained by greenhouse gas emissions linked to human activities.
Overheating oceans
The oceans, which absorb a large part of the excess heat, also reach critical levels. In March 2025, the average surface temperature of the seas climbed to 20.96 ° C, a record for this period of the year. This ocean overheating leads to:
an accelerated melting of polar ice;
a reduction in dissolved oxygen, impacting marine fauna;
Disturbances of marine currents and ecosystems.
A record melting with the poles
Satellite data confirm the magnitude of the phenomenon:
In the Arctic, the ice floe only covers 14.55 million km², 6 % less than the average of March.
In Antarctica, the extent of the ice remains 24 % lower than normal, a worrying deficit which is part of the continuity of negative records observed since the beginning of 2023.
Cascade effects on the planet
This acceleration of climate change causes chain consequences:
increased water stress in several regions;
drop in agricultural yields;
World security threats;
Increase in climatic disasters (heat waves, droughts, floods, etc.).
These multiple signals confirm that climate change is intensifying, with cascade effects on ecosystems, water resources, food safety and the frequency of extreme weather events.
