Will 2024 Top the Charts as the Hottest Year Yet?
In January 2024, the global average surface air temperature reached a record high of 13.14°C according to ERA5 data, which is 0.70°C above the 1991–2020 January average and 0.12°C higher than the previous warmest January in 2020.
Throwback to the hottest year on record to date — 2023:
In 2023, Earth experienced its warmest average surface temperature on record, according to NASA’s analysis. The global temperatures were approximately 2.1 degrees Fahrenheit (1.2 degrees Celsius) above the average for NASA’s baseline period from 1951 to 1980. Scientists from NASA’s Goddard Institute for Space Studies (GISS) in New York provided this information.
NASA Administrator Bill Nelson emphasized the urgency of addressing the climate crisis, noting that billions of people worldwide are already feeling its effects, such as extreme heat, wildfires, and rising sea levels. He highlighted ongoing efforts, including those led by President Biden and communities across America, to mitigate climate risks and enhance resilience.
Throughout 2023, hundreds of millions of people faced extreme heat, with each month from June to December setting global records for their respective months. July stood out as the hottest month ever recorded. Overall, Earth was about 2.5 degrees Fahrenheit (1.4 degrees Celsius) warmer in 2023 compared to the late 19th-century average, marking the beginning of modern record-keeping. NASA continues to utilize its space-based vantage point to gather critical climate data and make it accessible for all, supporting efforts to protect the planet for current and future generations.
In addition to the warming trend, scientists have investigated the impact of the January 2022 eruption of the Hunga Tonga-Hunga Ha’apai undersea volcano. This eruption released water vapour and fine particles, known as aerosols, into the stratosphere. A recent study revealed that these volcanic aerosols, by reflecting sunlight away from the Earth’s surface, caused a slight cooling effect of less than 0.2 degrees Fahrenheit (or about 0.1 degrees Celsius) in the Southern Hemisphere after the eruption.
Gavin Schmidt, a scientist involved in the study, emphasized that despite occasional cooling events like volcanic eruptions or aerosols, the overall warming trend will persist as long as greenhouse gas emissions continue to rise. Unfortunately, the past year saw a new record for greenhouse gas emissions, indicating the ongoing challenge of climate change.
NASA Deputy Administrator Pam Melroy stressed the importance of urgent and sustained actions to address climate change, highlighting recent legislation that includes significant investments to enhance America’s resilience to climate impacts. NASA’s Earth-observing satellites will continue to play a crucial role in providing comprehensive data about our changing planet, empowering people worldwide to make informed decisions regarding climate-related challenges.
Hottest January on the Mercury:
In January 2024, the global average surface air temperature reached a record high of 13.14°C according to ERA5 data, which is 0.70°C above the 1991–2020 January average and 0.12°C higher than the previous warmest January in 2020. This marks the eighth consecutive month with record warmth for its respective month. While the temperature anomaly for January 2024 was lower than the last six months of 2023, it remained higher than any month before July 2023.
Compared to the pre-industrial reference period of 1850–1900, January 2024 was 1.66°C warmer globally. The average global temperature for the past twelve months (February 2023 — January 2024) was also the highest on record, exceeding the 1991–2020 average by 0.64°C and the pre-industrial average by 1.52°C.
European temperatures in January 2024 varied significantly, with much below-average temperatures in the Nordic countries and much above-average temperatures in southern Europe. Outside Europe, temperatures were notably above average in eastern Canada, north-western Africa, the Middle East, and Central Asia, while being below average in western Canada, the central USA, and most of eastern Siberia.
Although El Niño in the equatorial Pacific began to weaken, marine air temperatures remained unusually high. The global sea surface temperature (SST) for January over 60°S–60°N set a new record at 20.97°C, surpassing the previous warmest January in 2016 by 0.26°C and ranking as the second-highest value in the ERA5 dataset, just 0.01°C shy of the record from August 2023. Recent daily SSTs also set new absolute records, exceeding previous highs from August 2023.
January 2024 — Sea Ice updates:
In January, the Arctic sea ice extent was near average and reached its highest level since 2009. Sea ice concentrations were above average in the Greenland Sea, a trend that has persisted since October, as well as in the Sea of Okhotsk. However, below-average concentrations were observed in the Labrador Sea during this period.
In contrast, the Antarctic sea ice extent ranked as the sixth lowest for January, registering 18% below the average. This is an improvement from the record low seen in January 2023 when it was 31% below average. Below-average sea ice concentrations were notably present in the Ross and Amundsen Seas, the northern Weddell Sea, and along the coast of East Antarctica during this time.
January 2024 — Hydrological highlights:
In January 2024, Europe experienced wetter-than-average conditions across large portions, with storms affecting north- and south-western regions. However, some areas like south-eastern and northern Spain, the Maghreb, southern UK, Ireland, eastern Iceland, most of Scandinavia, part of north-western Russia, and the eastern Balkans observed drier-than-average conditions.
Outside of Europe, several regions also saw wetter-than-average conditions in January. These areas include western and south-eastern USA, a significant portion of Eurasia, south-eastern South America, southeast Africa, and northern and eastern Australia. Conversely, drier-than-average conditions were observed across parts of western and southern North America, Canada, the Horn of Africa, the Arabian Peninsula, south-central Asia, Australia, and Chile. The dry conditions in some of these regions contributed to wildfires.
Top contributing factors behind rapid global temperature rise:
- Global Warming: 2011–2020 was the warmest decade recorded, with global average temperature reaching 1.1°C above pre-industrial levels in 2019. Human-induced global warming is presently increasing at a rate of 0.2°C per decade.
An increase of 2°C compared to the temperature in pre-industrial times is associated with serious negative impacts on to the natural environment and human health and well-being, including a much higher risk that dangerous and possibly catastrophic changes in the global environment will occur.
For this reason, the international community has recognised the need to keep warming well below 2°C and pursue efforts to limit it to 1.5°C.
2. Greenhouse gases: The main driver of climate change is the greenhouse effect. Some gases in the Earth’s atmosphere act a bit like the glass in a greenhouse, trapping the sun’s heat and stopping it from leaking back into space and causing global warming.
Many of these greenhouse gases occur naturally, but human activities are increasing the concentrations of some of them in the atmosphere, in particular:
- carbon dioxide (CO2)
- methane
- nitrous oxide
- fluorinated gases
CO2 produced by human activities is the largest contributor to global warming. By 2020, its concentration in the atmosphere had risen to 48% above its pre-industrial level (before 1750).
Other greenhouse gases are emitted by human activities in smaller quantities. Methane is a more powerful greenhouse gas than CO2 but has a shorter atmospheric lifetime. Nitrous oxide, like CO2, is a long-lived greenhouse gas that accumulates in the atmosphere over decades to centuries. Non-greenhouse gas pollutants, including aerosols like soot, have different warming and cooling effects and are also associated with other issues such as poor air quality.
Natural causes, such as changes in solar radiation or volcanic activity are estimated to have contributed less than plus or minus 0.1°C to total warming between 1890 and 2010.
3. Rising emissions:
A. Burning coal, oil and gas produces carbon dioxide and nitrous oxide.
B. Cutting down forests (deforestation). Trees help to regulate the climate by absorbing CO2 from the atmosphere. When they are cut down, that beneficial effect is lost and the carbon stored in the trees is released into the atmosphere, adding to the greenhouse effect.
C. Increasing livestock farming. Cows and sheep produce large amounts of methane when they digest their food.
D. Fertilisers containing nitrogen produce nitrous oxide emissions.
E. Fluorinated gases are emitted from equipment and products that use these gases. Such emissions have a very strong warming effect, up to 23,000 times greater than CO2.
