Sensible Heat Research Articles (Page 1)

Surface soil moisture–precipitation (SSM–P) coupling involves complex processes, with sensible heat (SH) and evapotranspiration as important mediators. However, these coupling pathways and their underlying mechanisms across the globe remain unclear, limiting hydrometeorological predictions and projections. Here, we employ an information flow technique to satellite observations and reanalysis, revealing strong local SSM impacts on precipitation across ~16% of analyzed global land. Among the eight identified coupling hotspots, the SH-mediated pathway emerges as a crucial mechanism, except for two African hotspots dominated by the evapotranspiration-mediated pathway. These pathway differences are linked to remote moisture availability and boundary layer height variability. Strong coupling preferentially occurs over regions with large SSM variability, particularly for SSM–SH–P. Most CMIP6 models fail to reproduce these coupling patterns, with only four successfully capturing the ERA5-derived variability–causality relationship. Our study offers additional insights into land–atmosphere coupling and proposes process-based metrics for model evaluation.

Abstract Previous studies have suggested that variability in the Gulf Stream (GS) region can lead North Atlantic atmospheric variability. However, it remains unclear what GS characteristic is most important in driving this lead time. Here, we show that the GS sensible heat flux (SHF) gradient specifically leads the North Atlantic Oscillation (NAO) by 1 month. This lag relationship occurs only when climatological sea‐surface temperature and SHF gradients are largest in late winter. Further analysis reveals that fine‐scale gradients (∼50 km) are critical. A month prior to a negative NAO, stronger than normal diabatic frontogenesis associated with anomalously strong SHF gradients is observed over the separated GS region. This is collocated with a North Atlantic eddy‐driven jet located in its Southern regime. These results suggest that knowledge of fine‐scale air‐sea heat flux gradients in late winter can potentially provide useful information about the NAO in weather forecasts and climate prediction systems.

Abstract. Eddy covariance observations play a pivotal role in understanding the land–atmosphere exchange of energy, water, carbon dioxide (CO2), and other trace gases, as well as the global carbon cycle and earth system. To promote the networking of individual measurements and the sharing of data, FLUXNET links regional networks of researchers studying land–atmosphere processes. JapanFlux was established in 2006 as a national branch of AsiaFlux. Despite the growing amount of shared data globally, the availability in Asia is currently limited. In this study, we developed an open dataset of the eddy covariance observations for Japan and East Asia, called JapanFlux2024, that was conducted by researchers affiliated with Japanese research institutions. The data were processed using selected standard methods from the FLUXNET community, with adaptations specific to the JapanFlux2024 dataset. Here, we present the data description and data processing and show the value of processed fluxes of sensible heat, latent heat, and CO2. The dataset will facilitate important studies for Japan and East Asia, such as land–atmosphere interactions, improvement of process models, and upscaling fluxes using machine learning and remote sensing technology, as well as bridge collaborations between Asia and FLUXNET.

Typhoon Yagi (2024) was a rapidly moving storm that lasted for eight days and made landfall in three locations, producing heavy rainfall over Hainan and Vietnam. This study aims to investigate the dynamical processes contributing to the heavy rainfall, concentrating on enthalpy flux (EF) and moisture flux (MF). The results indicate that both EF and MF increased significantly during the typhoon’s intensification stage and were high at the time of landfall. Before landfalling at Hainan, latent heat flux (LHF) reached 600 W/m2, while sensible heat flux (SHF) was recorded as 80 W/m2. Landfall at Hainan resulted in a decrease in LHF and SHF. LHF and SHF subsequently increased to 700 W/m2 and 100 W/m2, respectively, as noted prior to the landfall in Vietnam. The increased LHF led to higher evaporation, which subsequently elevated moisture flux (MF) following the landfall in Vietnam, while the region’s topography further intensified the rainfall. The mean daily rainfall observed over Philippines is 75 mm on 2 September (landfall and passing through), 100 mm over Hainan (landfall and passing through) on 6 September, and 95 mm at over Vietnam on 7 September (landfall and after), respectively. Heavy rainfall was observed over the land while the typhoon was passing and during the landfall. This research reveals that Typhoon Yagi’s intensity was maintained by a well-organized and extensive circulation system, supported by favorable weather conditions, including high sea surface temperatures (SST) exceeding 30.5 °C, substantial low-level moisture convergence, and elevated EF during the landfall in Vietnam.

Abstract Aerosol‐radiation interactions decrease the solar radiation reaching the surface, which cools the surface and influences land‐atmosphere interactions and affects the regional climate through various pathways. To estimate the change in radiative and nonradiative fluxes due to aerosol‐radiation interactions, regional climate model simulations were carried out over the South Asian region. Using the energy balance equation, aerosol‐induced changes in surface temperature are decomposed into its radiative (shortwave (SW) and longwave) and nonradiative (sensible heat flux (SHF), latent heat flux (LHF), and ground flux) components for different seasons. This study showed that the surface cooling due to the decrease in SW radiation is mainly compensated by the decrease in SHF in all seasons. The decrease in SHF is more than 50% of the decrease in SW radiation due to aerosols over the Indo‐Gangetic Plain (IGP). Aerosol‐induced changes in incoming longwave radiation have a cooling effect over the Indian region except over the western part of South Asia. The aerosol‐induced changes in LHF are highly heterogeneous and insignificant except for monsoon season. Over IGP, the decrease in LHF compensates nearly 15% of the SW cooling due to aerosols during monsoon season. Over the Indian region, approximately 40%–50% of the SW cooling due to aerosols is translated to net change in surface temperature, whereas the remaining is adjusted by the decrease of SHF and LHF. Notably, the impact of aerosol‐induced weakening of SHF remains unexplored but holds profound implications for the hydroclimate and air quality of the Indian subcontinent.

Thermal radiation is the process in which energy, in the form of electromagnetic radiation, is released from a heated surface in all directions and moves at the speed of light straight to its site of absorption. It doesn't need a medium to deliver it. The wavelengths of thermal radiation span from the shortest ultraviolet rays to the longest infrared rays through the visible light spectrum. The temperature of the emitting surface controls the radiant energy's distribution and intensity within this range. According to the Stefan-Boltzmann law, a surface's total radiant heat energy is proportional to the fourth power of its absolute temperature. In addition to surface net solar radiation (SNSR) and surface net solar radiation clear sky (SNSR clear sky) for noon, as well as surface net thermal radiation (SNR) and surface net thermal radiation clear sky (SNTR clear sky) for two times (00;00 am and 12:00 pm), data are collected by latent heat (LH), sensible heat (SH), and satellites recorded by the European Centre for Medium-Range Weather Forecasts Two latitudes (29.55 - 37.225) north of the equator and two longitudes (38.455 - 48.548) east of the Corniche line are covered by the 2021 over Iraq stations selection. The examination of the daily means of LH, SH, SNSR, SNSR clear sky, SNTR, and SNTR clear sky has been our focus otherwise. Spearman's test results demonstrated that, for all stations chosen in Iraq, there is a substantial correlation between thermal radiation types (SNTR clear sky, SNTR, and STRD) and latent heat and sensible heat, and that this correlation is positive for 2021. According to the test findings in Table 1, the Emadiyah station (SH & SNTR) at noon had the highest correlation coefficient in the Spearman's test (0.9), although the correlation coefficient for this station was the lowest across several stations.

Vegetation cover can be easily measured in the field by assessing the percentage of the ground that is covered by the existing vegetation. Aerial photographs or satellite images can be used for measuring vegetation cover in an extensive area. With time, vegetation cover can change, particularly for annual or perennial deciduous plants. Measuring the amount of vegetation is particularly crucial during the rainy season when soil erosion happens. In this work, the data of the European Center for Mediums-ranges Weathers Forecasts (ECMWF) was Low vegetation cover (LVC), High vegetation cover (HVC), Sensible heat (SH), and Latent heat (LH). Also. The research purpose was to find the relationship between LVC and HVC in the stations (Diyala, Mosul, and Arbil) for the period 2008-2022. The work was carried out with monthly and yearly mean data. It was found that there is an increase in low vegetation cover through the study period and this is due to Opinion and farmers' follow-up of low vegetation cover (for crops), and a decrease in high cloud cover through the study period this is due to the high temperatures and other weather factors such as the lack of rain. Also, the low cover has a heating effect on the weather, while the high cover has a cooling effect during the study period.

ABSTRACTThe Uttarakhand state of India has been witnessing spatiotemporal variations in heavy rainfall, posing landslides, avalanches, and risks to livelihood and infrastructure. The complex terrain (ranging 250–~7500 m) and weather in this part of the Himalayan region pose difficulties in maintaining land surface observations, thus creating uncertainties in surface energy and hydrological processes. The present study demonstrates the value of the high‐resolution land data assimilation system (HRLDAS) integrated at 2 km grid spacing from 2011 to 2021 over Uttarakhand and validated against in situ, satellite, and reanalyzes products. Diurnal variation of sensible heat flux (SHF), and latent heat flux (LHF) are closer to the in situ observations (−35 to 64 Wm−2) than the global and regional analysis (−125 to 129 Wm−2 and −40 to 172 Wm−2) during monsoon season. The HRLDAS soil moisture (SM) is overestimated against in situ and exhibited less error against European Space Agency Climate Change Initiative (ESACCI) (0.02 m3 m−3 with 30%) and Cyclone Global Navigation Satellite System (CYGNSS) (−0.02 m3 m−3 error with 21%). The HRLDAS performs better for soil temperature (ST) with high correlation and less bias (0.94°C and −0.34°C) than the GLDAS (0.83°C and −0.61°C) and IMDAA (0.86°C and 2.2°C), when verified against in situ observations. The spatial distribution of HRLDAS shows maximum ST in the southern parts and minimum ST in the northern parts of the Uttarakhand region and is consistent with the GLDAS and IMDAA during monsoon. HRLDAS shows lesser biases in net radiation (12 Wm−2), SHF (−10 Wm−2), and LHF (9.7 Wm−2) compared to GLDAS (25, −17, 10.3 Wm−2), and IMDAA (38, −11, 16 Wm−2), respectively. Besides the performance, the HRLDAS products represent better spatial heterogeneity than the coarser global and regional analysis and are useful to initialize numerical models.

Accurate estimation of air-sea fluxes is essential for advancing ocean modeling, observational studies, and understanding air-sea interactions. To address this need, the Indian National Centre for Ocean Information Services (INCOIS) developed and deployed a Flux Reference System (INCOIS-FRS) onboard ORV Sagar Nidhi. This article provides an overview of the system, its components, data acquisition methods, flux computation techniques, and preliminary results. The INCOIS-FRS integrates an Eddy Covariance Flux System (ECFS) and an Automated Weather Station (AWS). The ECFS collects high-frequency (20 Hz) data to directly estimate the latent heat flux (LHF), sensible heat flux (SHF), and momentum flux (τ) using the Eddy Covariance (EC) method. The AWS records meteorological and oceanic variables at 1 Hz, enabling flux estimates using the COARE 3.5 algorithm. A spectrally flat Class-A pyranometer and a pyrgeometer provide climate-grade measurements of downward shortwave and longwave radiation, which, combined with EC-derived SHF and LHF, yield the net heat flux. This article presents preliminary results inferred from data collected by INCOIS-FRS during a cruise in the Arabian Sea from 1–16 July 2023. Data from this system are useful for validating model outputs and satellite observations, refining flux parameterizations, marine boundary layer studies, and improving air-sea interaction models. INCOIS-FRS represents a first step toward equipping more oceanographic platforms, both crewed and uncrewed, with flux reference units. Future plans include expanding such deployments to enhance observational coverage and support research on air-sea fluxes across the Indian Ocean and other regions.

Cumulonimbus clouds that develop rapidly during summertime afternoons can cause local heavy precipitation and local flooding, particularly in urban areas. This study examines the potential to mitigate the severity of urban precipitation by reducing sensible heat flux (SHF). Large SHF characterizes urban areas due to anthropogenic factors such as heat emissions from buildings and roads, leading to the urban heat island effect. To assess the impact of SHF reduction, numerical simulations for an afternoon precipitation event in Osaka, Japan were conducted using the Weather Research and Forecasting (WRF) model. The nesting capability was used to increase the horizontal resolution to 0.5 km in the innermost domain. SHF reduction experiments were conducted by varying the reduction levels of SHF against no-reduction experiment (CTL) (ranging from 50 to 90% of CTL) and the size of the region of SHF reduction (the entire innermost domain, only urban grids of the innermost domain, and urban grids within a 20 km box of innermost domain). We created CTL and 15 types of reduction experiments with 8 ensemble members initialized at different times for each and a total of 128 members were created. The control experiment (CTL) reproduced the actual afternoon precipitation event. Results showed that SHF reduction experiments suppressed accumulated and peak precipitation in most cases compared to CTL. Extreme precipitation events, defined as precipitation above the 99.9th percentile value in CTL, were also less frequent in most cases. The most practical reduction experiment, 10% reduction level in the 20-km box area, resulted in a decrease of 18% in accumulated precipitation, 13% in peak precipitation, and 9% in the 99.9th percentile value of precipitation. These findings indicate that the reduction of SHF would stabilize the lower troposphere and hence would lead to reducing cloud formation and precipitation. This study demonstrates a potential for reducing SHF as a measure to mitigate urban precipitation under accelerating urbanization.

Given the important role of the land surface for climate, this study aims at (1) to evaluate the quality of the simulation of surface climate by the land-surface component of the EC-Earth3 ESM and (2) to assess the role of the coupling of the land surface with the atmosphere for the simulation of the surface climate in EC-Earth3. It is based on three simulations with different configurations of the EC-Earth3 ESM: an offline simulation with the land-surface component, a partially coupled simulation with the atmospheric component and a fully coupled simulation with the atmospheric component of EC-Earth3. The land-surface component of EC-Earth3 shows a characteristic geographical distribution of the biases for the different variables describing surface climate. As for the land-surface temperature, the model is characterized by warm biases in the tropics and the mid- and high latitudes of the Northern Hemisphere and a cold bias in the subtropics. For surface soil moisture, on the other hand, the model shows wet biases in the tropics and the mid- and high latitudes of the Northern Hemisphere and a dry bias in the subtropics. As for the surface energy fluxes, net radiation and sensible heat flux are underestimated in the tropics and the mid- and high latitudes of the Northern Hemisphere and overestimated in the subtropics, and the opposite behaviour is found for latent heat flux. The land-surface component of EC-Earth3 is characterised by an overall cold bias and a general underestimation of net radiation and sensible heat flux. Neither the coupling with the atmosphere nor the feedback between the land surface and the atmosphere affect the geographical distribution of the biases in surface climate characterising the offline simulation with the land-surface component of EC-Earth3 but have impacts on the magnitude of the local biases and regional details. The coupling with the atmosphere decreases land-surface temperature in the tropics and the mid- and high latitudes of the Northern Hemisphere and increases land-surface temperature in the subtropics, resulting in colder land-surface temperature and, thus, amplifying the overall cold bias found in the offline simulation. The feedback between the land surface and the atmosphere, on the other hand, increases land-surface temperature in the tropics and the mid-latitudes of the Northern Hemisphere and decreases land-surface temperature in the subtropics and the high latitudes of the Northern Hemisphere. The overall effect of the feedback between the land surface and the atmosphere is notably smaller than the effect of the coupling with the atmosphere for land-surface temperature and net radiation, similar for the fluxes of sensible and latent heat and stronger for surface soil moisture. The results of this study emphasize the need to improve the quality of the land-surface component of EC-Earth3 parallel with other components of the ESM.

Abstract The separate effects of the sensible heat flux (SHF) and latent heat flux (LHF) on the outer spiral rainbands of tropical cyclones (TCs) have not received sufficient attention. This study examines the separate contributions of the SHF and LHF to the outer spiral rainbands of TCs via a series of sensitivity experiments using the three‐dimensional cloud‐resolving Weather Research and Forecasting model. The results indicate that removing the outer SHF suppresses the activity of the outer spiral rainbands and results in a stronger and smaller‐scale TC, whereas decreasing the outer LHF by the same amount has only a slight impact on the outer spiral rainbands. Further investigations indicate that the positive radial gradient of the potential temperature at the cold‐pool outer edge is crucial for the strength of outer spiral rainbands. The strong positive radial gradient of the potential temperature gives rise to a negative radial gradient of the horizontal pressure at the cold‐pool outer edge, and thus an outward radial pressure gradient force. As a result, strong outflow exists near the cold‐pool outer edge, producing horizontal convergence and eventually lifting air to generate new convective cells. Distinct from the LHF, the SHF directly modulates the potential temperature immediately outside the cold pool and thus the radial gradient of the potential temperature at the cold‐pool outer edge. Removing the outer SHF leads to a significantly lower potential temperature outside the cold pool, which is averse to the formation of a larger radial gradient of the potential temperature at the cold‐pool outer edge.

Cold Surge (CS) events are often associated with rainfall occurrences in the Jakarta area. However, there is still limited literature on how CS affects other parameters in Indonesia. This study aims to contribute to this literature, particularly regarding the crucial role of CS in the interaction between the ocean and the atmosphere. This research uses the composite difference method to compare changes in Wind Speed (WS), Latent Heat Flux (LHF), Sensible Heat Flux (SHF), Shortwave Radiation (SWR), Longwave Radiation (LWR), and Net Surface Heat Flux (NSHF) during CS phases versus neutral conditions no CS (nCS). The composite difference results indicate an increase in wind speed in the study area, Natuna Sea, with values of 1.17 m/s, 1.45 m/s, and 1.69 m/s for December, January, and February, respectively. This finding explains that the increase in wind speed significantly influences LHF in the negative direction, meaning more LHF is transferred from the ocean to the atmosphere during the CS phase. LHF also predominantly affects NSHF in the study area during the CS period, indicating that more NSHF is leaving the ocean and entering the atmosphere compared to the amount entering the ocean from the atmosphere during the CS phase.

Trends in the air–sea freshwater and heat fluxes and hydrographic properties of the Mediterranean Sea are investigated to assess changes in dense water formation over 1979–2023 and 2004–2023. Results show a strong annual evaporation increase that has accelerated over the last two decades following the higher warming rate. Positive trends in winter latent heat flux (LHF) were obtained over 1979–2023 in most of the East Mediterranean, driving an increase in both the ocean heat loss and the haline component of the surface density flux, but there were no significant long-term trends over the western basin and the dense water formation sites. Results show much larger trends over 2004–2023 when a broadscale decrease in sensible heat flux (SHF) is obtained over the western basin as the air temperature is increasing much faster than SST. Decreasing (increasing) LHF and SHF resulted in largely reduced (enhanced) ocean heat loss during winter in the Gulf of Lions (Aegean Sea) over 2004–2023. Robust positive trends are obtained for both the salinity and temperature fields throughout the basin, with accelerated warming and salinification rates after the 2000s. Deep waters have become warmer but also much saltier and denser over recent decades. A water mass transformation method is also used to investigate changes in volumetric distribution in temperature/salinity/density and T/S space. Results suggest that salinification over the last 45 years may have strongly enhanced salt preconditioning in all major dense water formation sites, sustaining or even increasing deep water formation despite the increasingly warming climate.

Abstract Accurate quantification of turbulent heat fluxes [THF, comprising sensible heat flux (SHF) and latent heat flux (LHF)] and Bowen ratio (β, ratio of SHF and LHF) is essential for understanding the air-sea interaction. However, the biased estimates of SHF and LHF by widely applied bulk aerodynamic models, and the separate estimates of SHF and LHF by data-driven models, both may result in unrealistic β estimates. This study for the first time innovatively proposes a Bowen ratio-informed data-driven model (BrTHF) for coordinating the estimations of THF and β using the multivariate random forest technique and a combination of eddy covariance flux observations and meteorological and oceanic observations collected from 53 historical cruises. The result shows that the BrTHF model could not only achieve high-accuracy SHF and LHF estimates, but also avoid the outliers of β estimates that were commonly found in un-synergistic random forest and well-known COARE3.5 models.

Influence of clouds on planetary boundary layer height: A comparative study and factors analysis

Surface heat source (SHS) is a crucial factor affecting local weather systems. Particularly SHS on the Tibetan Plateau (TP) significantly influences East Asian atmospheric circulation and global climate. Accurate prediction of summer SHS on the TP is of urgent demand for economic development and local climate change. To evaluate the performance of SHS on the TP, the observed SHS data from the eleven sites on the TP verified against CRA40-land (CRA) is evidenced significantly better than ERA5-land (ERA5), another widely used reanalysis. The predictive capability of the CMA Climate Prediction System Model (CMA-CPS) for SHS on the TP was assessed using multiple scoring methods, including the anomaly correlation coefficient and temporal correlation coefficient, among others. Furthermore, relative variability and trend analysis were conducted. Finally, based on these assessments, the causes of the biases were preliminarily discussed. The CMA-CPS demonstrates a reasonable ability to predict the spatial distribution patterns of SHS, sensible heat (SH), and latent heat (LH) on the TP in summer. Specifically, the prediction results of SHS and LH exhibit an “east-high and west-low” distribution, while the distribution of the predicted SH is opposite. Nevertheless, the predicted values are generally lower than CRA, particularly in interannual variations and trends. Among the predictions, LH exhibits the highest temporal correlation coefficients, consistently above 0.6, followed by SHS, while SH predictions are less accurate. The spatial distribution and skill scores indicate that LH on the TP contributes more significantly to SHS than SH in summer. Furthermore, discrepancies in the predictions of surface temperature gradients, ground wind speed, and humidity on the TP may partly explain the biases in SHS and their components.

High-resolution data from an automatic weather station (for 45 days in July–August 2021) installed at the level of the perrenial snowline of the Sygyktinsky Glacier (Kodar Ridge, south of the Eastern Siberia) were used to simulate ablation with daily resolution. Ablation was measured conventionally (using snow stakes and ultrasonic sensor) and calculated basing on a surface heat balance (SHB). The average and total values of measured and calculated ablation are in a good agreement with each other, while daily fluctuations in the ablation may differ due to changes in the surface density. It was found that the calculation of ablation based on thermal balance is the most accurate and physically justified. The average magnitude of energy spent on melting the glacier was 81 W/m2. The greatest contribution to melting is made by the radiation balance (70 W/m2, 86%), and especially by the shortwave radiation balance (76 W/m2, 94%). The long-wave radiation balance was slightly negative (–7 W/m2) that means that the glacier was losing heat. The turbulent fluxes of latent and sensible heat were positive on all days, but their total contribution was insignificant (10 W/m2, 13% of the melting energy). The reason for the low values of turbulent heat is the weak wind speeds which are typical for the Kodar region in summer. Significant statistical correlations of ablation with the cloudiness, precipitation, atmospheric pressure, air temperature and relative humidity were found. The relationship of the melting rate with meteorological parameters is controlled mainly by the short-wave radiation balance, and not by the turbulent heat flows. Two the T-index models (regression and “degree-day” ones) were tested using the meteorological data. Both models reproduce the mean and total ablation well (deviation ≤ 9%), but the daily fluctuations in ablation are simulated with significant error (standard error of about 50%). The use of different “degree-day factor” (DDF) coefficients for snow and ice allows improving the model accuracy up to 44%. The T-index models best estimate ablation for snow surface (standard error ≤26%), and they may be improved by taking into account shortwave radiation and weather conditions.

Variability of the total heat balance (HB) of the Barents Sea during the cold period of the year has been studied. The cold period is that of cooling of the sea surface when the heat flux is permanently oriented towards the atmosphere. The contribution of two major components of the HB, i. e. sensible and latent heat fluxes, to the observed increase of the total winter heat transfer at the sea-atmosphere interface has been estimated. Data on short-wave and long-wave radiation fluxes, and sensible and latent heat values were obtained from the atmos-pheric reanalysis of the European Center for Medium-term Weather Forecasting ERA5. HB of the sea surface was calculated as a sum of short-wave and long-wave radiation fluxes and those of sensible and latent heat. The total HB, as well as the total flux of sensible and latent heat for the cold period were calculated by summing up the corresponding values between the start and end dates of the cooling season. Calculations demonstrated an increase in the sum of HB over the cold season for the northern part of the Barents Sea (up to 2000 MJ/m2 over 40 years), and a decrease in the southern part of the sea (up to 1000 MJ/m2 over 40 years). In the northern part of the sea, the contribution of sensible and latent heat fluxes decreases to 0,3-0,4. The observed trend of sum of HB over the cold season and its turbulent components could with high probability be explained by increasing difference between air temperature and sea surface temperature.

Abstract. Long-term tall-tower eddy-covariance (EC) measurements have been recently established in three European pilot cities as part of the ICOS-Cities project. We conducted a comparison of EC software to ensure a reliable generation of interoperable flux estimates, which is the prerequisite for avoiding methodological biases and improving the comparability of the results. We analyzed datasets covering 5 months collected from EC tall-tower installations located in urbanized areas of Munich, Zurich, and Paris. Fluxes of sensible heat, latent heat, and CO2 were calculated using three software packages (i.e., TK3, EddyPro, and eddy4R) to assess the uncertainty of flux estimations attributed to differences in implemented postprocessing schemes. A very good agreement on the mean values and standard deviations was found across all three sites, which can probably be attributed to a uniform instrumentation, data acquisition, and preprocessing. The overall comparison of final flux time series products showed a good but not yet perfect agreement among the three software packages. TK3 and EddyPro both calculated fluxes with low-frequency spectral correction, resulting in better agreement than between TK3 and the eddy4R workflow with disabled low-frequency spectral treatment. These observed flux discrepancies indicate the crucial role of treating low-frequency spectral loss in flux estimation for tall-tower EC systems.