2023 Global Warming Highs
Earth experienced its warmest average surface temperature on record in 2023, with a 1.2 degrees Celsius increase over NASA's baseline period (a period used as reference when monitoring climate change), of 1951-1980. July marked the hottest month ever recorded. Earth was about 1.4°C warmer than the average temperature of the late 19th-cent-
ury (Kirk, 2023). Gavin Schmidt, Goddard Institute for Space Studies (GISS) director, highlights the unprecedented warming caused by fossil fuel emissions, leading to heatwaves, intense rainfall, and coastal flooding. While long term warming is attributed to human activities, El Niño (a climate phenomenon characterized by warmer than average sea surface
temperatures in the Pacific Ocean), aerosols, and volcanic eruptions are factors that should be considered for short term warming (Kirk, 2023).
In 2023, El Niño-Southern Oscillation (ENSO) played a key role in Earth's climate. ENSO is characterized by the warming and cooling of sea surface temperatures in the central and eastern Pacific Ocean. The two phases involved in ENSO are El Niño (warming) and La Niña (cooling). The Pacific Ocean transitioned from three consecutive La Niña events (cooling) to El Niño (warming) in May 2023, known for coinciding with record-high temperatures (Kirk, 2023). Despite the El Niño's peak expected in February-April, the record temperatures in late 2023 occurred earlier. Scientists also considered the impact of the Hunga Tonga-Hunga Ha'apai volcano eruption in January 2022, which caused a slight cooling in the Southern Hemisphere. However, Gavin Schmidt, emphasizes that despite the cooling factor, continuous greenhouse gas emissions produce way warmer temperatures. Greenhouse gas emissions hit a new record in 2023, emphasizing the urgency of addressing climate change (Kirk, 2023).
Aerosols have also been studied extensively over the past decade, for both their cooling and warming effects (Aerosols: are SO2 emissions reductions contributing to global warming, 2023). Natural aerosols, such as those from volcanic eruptions, can emit sulfur dioxide gas into the stratosphere. Due to the sulfates’ light colouring, sunlight tends to reflect off the particles promoting the cooling phenomenon seen in the Hunga Tonga-Hunga Ha'apai eruption. However, soot, a particulate matter that is dark in colour and often a result of burning fossil fuels, have a tendency to absorb sunlight directly resulting in warmer atmospheres. Sources of soot are much more common in daily life, among which are wildfires, industrial fuel, combustion engines, etc. Although short-lived, soot and sulfates have demonstrated a negative impact on human health due to their persistent production. Air pollution as a result of aerosols have resulted in up to 8 million deaths annually. Any short-term cooling effects of aerosols are simultaneously negated by similar atmospheric warming phenomena, as well as subsequent health impacts years later (Aerosols: are SO2 emissions reductions contributing to global warming, 2023).
NASA and other climate related organizations seek to publicize valuable meteorological data, enabling access for anyone from key decision makers to ordinary citizens (NASA Goddard Space Flight Center, 2024). Analysis of air temperatures as well as those of sea surface temperatures point to the same conclusions: global surface temperatures measured in 2023 are at a record high (NASA Goddard Space Flight Center, 2024). And while short-term warming effects of natural and manmade sources need immediate attention, drastic legislative changes need to be made to ensure the long term well-being of the planet and the people living on it. By making climate data readily accessible to the public, NASA hopes to promote informed lifestyle choices (NASA Goddard Space Flight Center, 2024).
References
Aerosols: are SO2 emissions reductions contributing to global warming? (2023, August 1). Copernicus. https://atmosphere.copernicus.eu/aerosols-are-so2-emissions-reductions-contributing-global-warming
Kirk, K. (2023, June 12). Aerosols: Small Particles with Big Climate Effects. Climate Change: Vital Signs of the Planet. https://climate.nasa.gov/explore/ask-nasa-climate/3271/aerosols-small-particles-with-big-climate-effects/
NASA Goddard Space Flight Center. (2024, January 14). NASA analysis confirms 2023 as warmest year on record. ScienceDaily. https://www.sciencedaily.com/releases/2024/01/240114195023.htm