The worst-case scenario is that there is likely an 80% chance that at least one year between 2025 and 2029 will be warmer than the warmest year on record (currently held by the year 2024), and there is an 86% chance that at least one year will be more than 1.5°C above the pre-industrial level.
By Salam Rajesh
If it is of any solace for the global community, the World Meteorological Organization (WMO) has forewarned that the annually averaged global mean near-surface temperature for each year between 2025 and 2029 is predicted to be between 1.2°C and 1.9°C higher than the average over the years 1850-1900 (the pre-industrial period).
The worst-case scenario is that there is likely an 80% chance that at least one year between 2025 and 2029 will be warmer than the warmest year on record (currently held by the year 2024), and there is an 86% chance that at least one year will be more than 1.5°C above the pre-industrial level.
The WMO’s State of the Global Climate 2024 report released in March earlier this year had confirmed that the year 2024 was likely the first calendar year to be more than 1.5°C above the 1850-1900 average, with a global mean near-surface temperature of 1.55 ± 0.13°C above the 1850-1900 average. It does not sound too well for the blue planet and the billions of human population it supports.
This does assert that year 2024 was the warmest year in the 175-year observational record. The current level of warming had caused more harmful heatwaves, extreme rainfall events, intense droughts, uncontrollable wildfires, melting of ice sheets, sea ice, and glaciers, heating of the ocean, and rising sea levels, according to the WMO.
At this scale of forewarning, the Arctic warming over the next five extended winters, that is, between November and March, is predicted to be more than three and a half times the global average, that is, at 2.4°C above the average temperature during the most recent 30-year baseline period of 1991 to 2020.
The Paris Climate Agreement concluded in 2015 had urged member countries to hold the increase in long-term global average surface temperature well below 2°C above the pre-industrial levels, and, thereto, pursue efforts to limit the increase to 1.5°C. The 1.5°C (and 2.0°C) level specified in the Paris Agreement refers to long-term level of warming inferred from global temperatures, typically over a period of 20 years.
The predicted precipitation patterns for May to September between 2025 and 2029, relative to the 1991-2020 baseline, suggest wetter than average conditions in the Sahel, northern Europe, Alaska and northern Siberia, and drier than average conditions for this season over the Amazon, as per the WMO report.
Recent years in the South Asian region have been wetter than average and the forecast suggests this will continue for the 2025-2029 period, the WMO report noted.
Reflecting upon the report, WMO’s Deputy Secretary-General Ko Barrett says, “We have just experienced the ten warmest years on record. Unfortunately, this WMO report provides no sign of respite over the coming years, and this means there will be a growing negative impact on our economies, our daily lives, our ecosystems, and our planet”.
“Continued climate monitoring and prediction is essential to provide decision-makers with science-based tools and information to help us adapt”, she said.
The scientific community has repeatedly warned that the warming of more than 1.5°C risks unleashing far more severe climate change impacts and extreme weather, and every fraction of a degree of warming matters. This year’s UN climate change conference, COP30, will consider updated climate action plans on the Nationally Determined Contributions (NDCs) of member countries which are crucial for achieving the Paris Agreement goals, WMO noted.
The Intergovernmental Panel on Climate Change (IPCC) defines future global warming levels in terms of a 20-year mean. The WMO report presented three methods for estimating the current global warming level, with central estimates ranging from 1.34°C to 1.41°C compared to the 1850-1900 baseline based on a range of methods.
One of the best known examples of climate extremity in recent years was the formal declaration of the ‘death’ of Iceland’s Okjökull glacier in 2014. It was the first glacier, globally, to be officially declared dead as a result of human-caused climate change. The Okjökull was a dome-shaped glacier located 71 kilometers northwest of Reykjavík in Iceland.
In 2023, Iceland also created the world’s first iceberg graveyard, where ice-like headstones were constructed for the 15 major glaciers listed on the Global Glacier Casualty List, all of which are either dead or critically endangered due to climate change impacts. The list also included the Anderson Glacier in Washington State, which in 2015 became the first U.S. glacier to be declared officially ‘dead’.
The worry is not only about glacial melts and sea level rise, resulting in gradual submergence of low lying countries. The more worrisome issue on the climate front is of food security, or insecurity.
Researchers from Aalto University, Finland; University of Göttingen, Germany; and University of Zürich, Switzerland studied 30 major crops under four scenarios of global warming levels ranging from 1.5°C to 4°C, and found that a considerable increase in the share of agricultural areas shifting to unprecedented climatic conditions could happen if global warming exceeds 2°C.
The study published in Nature Food, forewarned that at least half of the global crop production in low latitude areas could be jeopardized as and when global warming surpasses the threshold of 1.5 degrees Celsius, and climate conditions subsequently become unsuitable for food production.
At the same time, there is also a threat to crop diversity as it was projected to decline on 52 percent of global cropland in a scenario of global warming exceeding 2°C and on 56 percent if warming exceeded 3°C, the study warned. This scenario threatens the objectivity of the SDG1 and SDG2 goals of the United Nations.
The World Meteorological Organization is a specialized agency of the United Nations and is responsible for promoting international cooperation in atmospheric science and meteorology. WMO monitors weather, climate, and water resources and provides support to its Members in forecasting and disaster mitigation. The organization is committed to advancing scientific knowledge and improving public safety and well-being through its extensive work.