*Article* **Estimation of Sensible and Latent Heat Fluxes Using Surface Renewal Method: Case Study of a Tea Plantation**

**Jizhang Wang 1, Noman Ali Buttar 1,2, Yongguang Hu 1,\*, Imran Ali Lakhiar 1, Qaiser Javed <sup>1</sup> and Abdul Shabbir 1,2**


**\*** Correspondence: deerhu@ujs.edu.cn; Tel.: +86-511-8879-7338

**Abstract:** An experiment of sensible and latent heat flux measurement was conducted in a tea plantation near the Yangtze River within Danyang of Jiangsu Province, China. High-frequency (~10 Hz) air temperature measurement with fine-wire thermocouples ( = 50 μm) was used for the estimation of sensible heat flux (*H*), and latent heat flux (*LE*) was extracted as a residual of the energy balance equation using additional measurements of net radiation (*Rn*) and soil heat flux (*G*). Results were compared against the eddy covariance (EC) system under unstable conditions only, and days with high precipitation were excluded from further analysis. Half-hourly datasets of the sensible heat flux estimated using the surface renewal method (SR) (*HSR*) and measured by the EC system (*HEC*) were analyzed. Results showed good agreement with *R2* = 0.80, root mean square error (*RMSE*) = 27.87 W m<sup>−</sup>2, relative error (*RE*) *=* 9.02%, and a regression slope of 0.68—this slope was used for the calibration of the uncalibrated *HSR* estimated by SR. On the other hand, the half-hourly dataset of *LESR* was regressed against EC, and it showed good agreement with relatively high *R<sup>2</sup>* = 0.93, *RMSE* = 32.99 W·m<sup>−</sup>2, and *RE* = 5.67%. Hence, the SR method may estimate the surface fluxes at a relatively low cost, ultimately improving calculations of evapotranspiration. Thus, the SR method could provide an economical tool for improving crop water management of tea plantations.

**Keywords:** sensible and latent heat fluxes; surface renewal method; tea plantation; evapotranspiration; eddy covariance
