Nivar

Nivar

Examining the Latest State the Climate and Its Changes on a Global and National Scale

Document Type : Original Article

Author
Sahrar Tajbakhsh
Member of the faculty of the Institute of Meteorology and Atmospheric Sciences
10.30467/nivar.2025.529698.1340
Abstract
This paper examines the latest state of the climate in the world and Iran, and introduces anomalies in key weather and climate indicators. Global climate information has been compiled using real-time data and re-analysis data based on reports from the World Meteorological Organization (WMO). For Iran, data measured at more than 1,000 stations nationwide has been used. In areas where data are lacking, well-established interpolation methods have been applied. Key findings from recent studies reveal that the average temperature at the 2-meter surface level in 2024 was 1.55 ° C ± 0.13 ° C higher than the mean temperature of 1850-1900 (the pre-industrial period). This marks 2024 as the warmest year in 175 years on record, clearly surpassing the previous record set in 2023 (1.45°C ± 0.12°C above the 1850–1900 average). Notably, each of the past ten years, 2015–2024, has been a record-breaking year for global temperature. In 2024, ocean temperature reached its highest level in 65 years of observational records, surpassing the previous record set in 2023. A new record for ocean temperature has been set annually for the past eight years. Furthermore, the rate of ocean warming over the past two decades, 2005-2024, has been more than doubled compared to the period 1960-2005. In 2024, global average sea level also reached unprecedented heights in 2024, based on satellite data available since 1993. The rate of global average sea level rise over the past decade (2015-2024) was more than double the rate observed during the first decade of satellite records (1993-2002). The strong 2023/2024 El Niño followed three consecutive years of La Niña from late 2020 to early 2023. El Niño conditions were established by mid-2023, intensified by the end of the year, and dissipated in the second quarter of 2024. The World Meteorological Organization (WMO) report on the State of the Global Climate in 2023 and 2024 confirms that all major climate indicators are breaking records. These two years (2024 and 2023) stand as the hottest years in Erath's recorded history (175 years). In Iran, extreme weather events—including torrential rainfall, heat waves, and strong winds—have become increasingly frequent in 1402 and 1403 in Persian Calendar. Aging infrastructure, extensive land-use changes, along with an increase in the occurrence of weather and climate extreme events, have led to an increase in damages and casualties. For optimal management, it seems necessary to develop the I.R. of Iran Meteorological Organization's observation network for better monitoring and issuing more accurate forecasts and warnings, as well as decision-making for major decisions.
Keywords
Climate change
extreme indices
Heat wave
Drought
Evapotranspiration
Subjects
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  • Receive Date 10 June 2025
  • Revise Date 13 August 2025
  • Accept Date 17 August 2025
  • Publish Date 17 August 2025