The Trends in Climate and Determination of Climate-Yield Relationships in Different Tea-Growing Regions of Sri Lanka during the Period from 2010 to 2024

DOI

10.2991/978-94-6239-646-3_17How to use a DOI?

Keywords

Climate change; tea yield; temperature; rainfall; water balance

Abstract

This work determined the temporal trends in key climatic variables in different tea-growing regions of Sri Lanka during 2010-2024 and determined climate-yield relationships. Daily meteorological data from Talawakelle, Ratnapura, Hantana, Kottawa and Passara, were computed into monthly means of maximum (T_Max), minimum (T_Min) and mean (T_Mean) temperatures and monthly totals of rainfall (R_F) and pan evaporation (E_T). Primary water balance (W_B) was computed as the difference between monthly totals of R_F and E_T. Change in each climatic variable was computed as the difference (i.e. anomaly) in its monthly value from the respective monthly mean during the reference period 2010-2014. Anomalies of climatic variables showed different temporal trends at different locations. Talawakelle, Hantana and Kottawa showed increasing trends in T_Max whereas Ratnapura and Hantana showed increasing trends in T_Min. All locations except Passara showed increasing trends in T_Mean. Ratnapura and Kottawa showed increasing trends in R_F whereas the rest did not show significant temporal trends. Best-fitting multiple regression models for climate-yield relationships included the second-order polynomials of a temperature-related variable (T_Max or T_Min) and a water-related variable (R_F or W_B). Estimated temperature thresholds showed that current monthly temperatures in Ratnapura and Kottawa have already exceeded the thresholds beyond which yields begin to decline. In contrast, current temperatures in Talawakelle are close to the threshold while those in Hantana and Passara are still below the threshold. Estimated water-related thresholds show that increasing R_F or W_B will have positive impacts on tea yields in Ratnapura and Hantana, but negative impacts in other locations.

Copyright

© 2026 The Author(s)

Open Access

Open Access This chapter is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

Download article (PDF)

TY  - CONF
AU  - W. A. J. M. De Costa
AU  - B. L. D. S. M. Fernando
AU  - N. P. S. N. Bandara
AU  - A. L. R. U. Kumara
AU  - P. D. De Alwis
AU  - G. S. Pradeep
AU  - K. G. N. M. Gamage
AU  - U. C. Oliver
AU  - S. B. Edirisinghe
PY  - 2026
DA  - 2026/04/15
TI  - The Trends in Climate and Determination of Climate-Yield Relationships in Different Tea-Growing Regions of Sri Lanka during the Period from 2010 to 2024
BT  - Proceedings of the International Tea Symposium (InTSym100 2025)
PB  - Atlantis Press
SP  - 291
EP  - 316
SN  - 2468-5747
UR  - https://doi.org/10.2991/978-94-6239-646-3_17
DO  - 10.2991/978-94-6239-646-3_17
ID  - DeCosta2026
ER  -