DIURNAL TEMPERATURE RANGE VARIABILITY OVER KARNATAKA, INDIA: SPECTRAL EVIDENCE OF INTERANNUAL AND DECADAL CLIMATE MODES (1958–2024)
DIURNAL TEMPERATURE RANGE VARIABILITY OVER KARNATAKA, INDIA
13 / 6
Authors
-
SRINIVASA SASDHAR PONNALURU
Keywords:
Climate Variability, Diurnal temperature range, ENSO, Karnataka, Spectral analysis.Abstract
Diurnal temperature range (DTR), defined as the difference between daily maximum and
minimum temperatures, is an important indicator of climatic variability and land–atmosphere
interactions. This study examines the temporal variability of DTR over Karnataka, India, using
monthly temperature data for 1958–2024. Monthly DTR anomalies were analysed using Welch
and Lomb–Scargle spectral techniques with statistical significance assessed against an AR(1)
red-noise background. The results reveal variability across multiple timescales, including
interannual (H=2–5 years), sub-decadal (H=8–9 years), and a statistically significant decadal
cycle near 16–17 years. Additional low-frequency variability around 30 years indicates gradual
climatic modulation of DTR. These findings highlight the presence of multi-timescale climate
variability influencing diurnal temperature behaviour in southern India, with potential implications
for agricultural planning and climate adaptation.
References
Abatzoglou, J. T., Dobrowski, S. Z., Parks, S. A., and Hegewisch, K. C. 2018. TerraClimate, a high-resolution global
dataset of monthly climate and climatic water balance from 1958–2015. Scientific Data, 5, 170191. https://doi.org/10.1038/sdata.2017.191
Donat, M. G., Lowry, A. L., Alexander, L. V.,O’Gorman, P. A., and Maher, N. 2016. More extreme precipitation in the world’s dry and wet regions. Nature Climate Change, 6, 508–513. https://doi.org/10.1038/nclimate2941
IPCC (2021). Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge. https:// doi.org/10.1017/9781009157896
Krishnan, R., Sanjay, J., Gnanaseelan, C., Mujumdar, M., Kulkarni, A., and Chakraborty, S. 2020. Assessment of Climate Change over the Indian Region.Springer Nature, Singapore. https://doi.org/10.1007/978-981-15-4327-2
Lesk, C., Rowhani, P., and Ramankutty, N. 2016. Influence of extreme weather disasters on global crop production.Nature, 529, 84–87. https://doi.org/10.1038/nature16467
Lobell, D. B., Hammer, G. L., McLean, G.,Messina, C., Roberts, M. J., and Schlenker, W. 2015. The critical role of extreme heat for maize production in the United States. Nature Climate Change, 3, 497–501. https://doi.org/10.1038/nclimate1832
Downloads
Submitted
Published
Issue
Section
License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
The author owns the article's copyright until the article is accepted for publication. After acceptance, the author(s) assigns the article's copyright jointly to both the authors and the Publishers of the Journal of Research ANGRAU (ANGRAU) and licensed under a Creative Commons Attribution-Non Commercial-Share Alike 4.0 International License.
