Tropical belt expansion and its impacts on climate variability in the Mediterranean from 1980 to 2022
- 1National Research Institute of Astronomy and Geophysics (Helwan, Egypt)
- 2Anhui University (Hefei, China)
- 3Henan Polytechnic University (Jiaozuo, China)
Abstract
This paper explores the long-term variability of climatic parameters over the Mediterranean region and their relationship with tropical belt expansion by investigating observational and reanalysis data from January 1980 to December 2022 through multiple approaches, including correlation, linear regression, and singular value decomposition (SVD) analysis. The lapse rate tropopause height exhibits upward trends of approximately 80.58 m per decade. Concurrently, the tropical belt shows a poleward expansion of approximately 0.14 and 0.27° per decade, estimated using the tropopause drop and tropopause gradient methods, respectively. The tropical edge latitudes (TELs) of both applied approaches show an evident seasonal variation. In addition, the two TEL definitions exhibit consistent correlation patterns with surface temperature (Ts), lower tropospheric temperature (Trp-1), upper tropospheric temperature (Trp-2), precipitation, and the Standardized Precipitation Evapotranspiration Index (SPEI). The results of the SVD analysis depict that although the leading mode explains the majority of the covariance between TELs and the examined climatic parameters, the second coupled mode shows more localized spatial structures, with TELs pronouncedly coupling with Ts and Trp-1 in the eastern Mediterranean. Furthermore, Ts and Trp-1 have significant increasing trends, which are abundant in the eastern Mediterranean. On the other hand, both precipitation and SPEI exhibit downward trends. Over the Mediterranean region, climatic parameters show an apparent spatial and temporal variation. The results confirm the linkage between climatic parameters' trends and variability with the TELs' variability patterns over the study area, especially in the eastern Mediterranean region.
Versions
Related
- Holocene millennial climate variability influenced by tropical–Antarctic ocean–atmosphere interactions
- Thirty-five years of urban expansion and thermal transformation: Integrating LULC change climate variability and population growth
- Polar front jet regulates tropical sea surface temperature impacts on South China extreme precipitation
- An unprecedented Mediterranean tropical cyclogenesis attempt above extreme sea surface temperatures?
- Tropical impacts of the Southern Ocean underestimated by mean-state biases
BibTeX
@article{darrag2026tropical,
title = {{Tropical belt expansion and its impacts on climate variability in the Mediterranean from 1980 to 2022}},
author = {Mohamed Darrag and Shuanggen Jin and Andrés Calabia and Aalaa Samy and Ivan Radevski and Ali M. Radwan},
journal = {Atmospheric Chemistry and Physics},
year = {2026},
month = oct,
doi = {10.5194/acp-26-14031-2026},
url = {https://acp.copernicus.org/articles/26/14031/2026/},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Tropical belt expansion and its impacts on climate variability in the Mediterranean from 1980 to 2022
AU - Mohamed Darrag
AU - Shuanggen Jin
AU - Andrés Calabia
AU - Aalaa Samy
AU - Ivan Radevski
AU - Ali M. Radwan
PY - 2026
DA - 2026/10/06
JO - Atmospheric Chemistry and Physics
DO - 10.5194/acp-26-14031-2026
UR - https://acp.copernicus.org/articles/26/14031/2026/
AB - This paper explores the long-term variability of climatic parameters over the Mediterranean region and their relationship with tropical belt expansion by investigating observational and reanalysis data from January 1980 to December 2022 through multiple approaches, including correlation, linear regression, and singular value decomposition (SVD) analysis. The lapse rate tropopause height exhibits upward trends of approximately 80.58 m per decade. Concurrently, the tropical belt shows a poleward expansion of approximately 0.14 and 0.27° per decade, estimated using the tropopause drop and tropopause gradient methods, respectively. The tropical edge latitudes (TELs) of both applied approaches show an evident seasonal variation. In addition, the two TEL definitions exhibit consistent correlation patterns with surface temperature (Ts), lower tropospheric temperature (Trp-1), upper tropospheric temperature (Trp-2), precipitation, and the Standardized Precipitation Evapotranspiration Index (SPEI). The results of the SVD analysis depict that although the leading mode explains the majority of the covariance between TELs and the examined climatic parameters, the second coupled mode shows more localized spatial structures, with TELs pronouncedly coupling with Ts and Trp-1 in the eastern Mediterranean. Furthermore, Ts and Trp-1 have significant increasing trends, which are abundant in the eastern Mediterranean. On the other hand, both precipitation and SPEI exhibit downward trends. Over the Mediterranean region, climatic parameters show an apparent spatial and temporal variation. The results confirm the linkage between climatic parameters' trends and variability with the TELs' variability patterns over the study area, especially in the eastern Mediterranean region.
SN - 1680-7324
ER -