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Evapotranspiration (ET) is predominant variable for water management in various types of ecosystems, and it has been intensively studied through in situ measuring and modeling methods. However, it is challenging to measure actual ET and upscale it to regional level for karst landscapes, where aquifers typically show remarkable and rapid responses to precipitation events. There is an urgent need to quantify water fluxes to provide reliable evidence for the protection and sustainable management of karst water resources. Therefore, in this study, five plots were built to observe actual ET based on Thermal Dissipation Probes, redesigned ventilated chamber and in‐site microlysimeters in a karst watershed in southwest China. Then, three models (Penman‐Monteith‐Leurning, PML; Remote Sensing‐Priestley and Taylor; and Hargreaves) were constructed to upscale ET estimation to the regional level based on Landsat‐8 images and MODIS data. The results showed that: (a) The PML model performed better than other models (p < 0.01) with higher R2 values (0.72 for MODIS images and 0.87 for Landsat‐8 images); (b) Daily ET exhibited significant seasonal variability and different spatial distribution, and yearly ET exhibited well related with soil thickness (R2 = 0.58); (c) Daily ET had a slightly positive correlation with DEM, however, had a negative correlation with ground temperature. This study is helpful to improve accuracy of measured and estimated ET by combining remote sensing data, and it has important implications for upscaling it to regional level. It suggests that ET is strongly regulated by constant supply of water, vegetation coverage, and available energy in karst catchments. Plain Language Summary: Evapotranspiration (ET) process bonds water, energy cycle, and carbon cycles. Aiming to characterize ET processes and impact controls at regional level for karst landscapes, five plots were built to observe actual ET, and three models were selected to upscale ET estimation to the regional level using Landsant‐8 and MODIS data in this study. The results showed that the Penman‐Monteith‐Leurning model performed the best and additional validation data observed in experimental spots were identified and corresponded with satellite data. Vegetation coverage and the density of conducting tissue (e.g., LAI) both contributed to ET seasonality and the spatial distribution differences. Soil thickness is a key prediction for the ratio distribution of yearly evapotranspiration to precipitation in karst watershed in southwest China. Key Points: Multiple models based on different data sources exhibited different accuracy on evapotranspiration simulation in karst basinYearly evapotranspiration distribution is well related with soil thicknessGround temperature exhibited negative correlation with daily evapotranspiration [ABSTRACT FROM AUTHOR]

By using an acoustic Doppler velocimeter mounted on the seabed of the continental shelf of the northern South China Sea, high frequency velocity fluctuations were measured for 4.5 days. The turbulent kinetic energy dissipation rate was estimated. During the observation, the strong ocean response to Typhoon Rammasun was recorded to compare the turbulent characteristics before and during the typhoon. The results show that the turbulence near the seabed is mainly generated by the tidal current shear and exhibits a quarter diurnal variation during the period before the typhoon. During the typhoon period, the dissipation rate ε dramatically increased from 1 × 10−6 to 1 × 10−2 m2 s−3 within a short time, and the significant wave height and the surface wave orbital velocity showed the same tendency. This finding suggests that the turbulence is dominantly generated by the surface waves near the seabed. Plain Language Summary: Under typhoon conditions, the turbulence characteristic at the bottom boundary layer of the continental shelf is not clear. Therefore, the field observation was carried out, and the results show that the turbulence kinetic energy dissipation rate increases 4 orders under Typhoon Rammasun. This strong turbulence is dominantly generated by the surface waves near the seabed. Understanding the turbulence characteristics is important for studying turbulent mixing, turbulence parameterization, pollutant dispersion, sediment dynamics, and biological activities. Key Points: The strong turbulence was measured with ADV on the continental shelf of the northern South China Sea during Typhoon Rammasun in 2014The turbulent kinetic energy dissipation rate increases 4 orders of magnitude under typhoon conditionSea surface waves play a key role in the generation of strong turbulence in the wave bottom boundary layer [ABSTRACT FROM AUTHOR]