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Biophysical effects of land cover changes on land surface temperature (Ts), including two effects, that is, radiative effects (caused by surface albedo changes) versus non‐radiative effects (caused by changes in the energy flux distribution), have attracted the attention of many researchers. However, the uncertainties of land use and land cover (LULC) and vegetation schemes on non‐radiative effects, and the roles of non‐radiative effects on Ts, remain uncertain. In this study, we investigate the local impact of LULC differences by comparing Noah with multiparameterization (Noah‐MP) land model simulations with different LULC data sets and those with vegetation schemes whether they include interactive canopies. We attribute Ts changes induced by LULC differences obtained from Noah‐MP simulations to radiative and non‐radiative effects over East Asia based on the decomposed temperature metric theory. The results indicate that vegetation cools Ts over urban regions by 4.0–6.0°C. Grassland and cropland decrease the Ts over barren regions. Forests are warmer (cooler) than grassland and cropland in high latitudes (in mid and low latitudes). Grassland is cooler than cropland. However, the magnitude of Ts changes induced by these differences is lower than that induced by differences between vegetation and urban. The non‐radiative effect generally explains more than 50% of the local changes in Ts. The interactive canopies enlarge Ts changes for afforestation or replacements of urban region by vegetation. The effect of uncertainties in LULC data sets is negligible. This study highlights the importance of non‐radiative biophysical effects and interactive canopies on local changes in Ts. Plain Language Summary: The biophysical effects of land cover changes on land surface temperature (Ts) cannot be ignored while assessing the impact of land cover changes. The role of non‐radiative effect, one of the two forcing effects of the biophysical effects, remains uncertain. In this study, we investigate the local impact of different land cover types on Ts by comparing land model simulations with different land cover data sets and vegetation schemes whether they include interactive canopies. The non‐radiative effect dominates the local changes in Ts over East Asia. The interactive canopies could enlarge the Ts changes for afforestation or replacements of urban region by vegetation. However, the effect of uncertainties in land cover data sets on Ts changes and non‐radiative effect induced by different land cover types is negligible. Key Points: Forests, grassland, and cropland largely cool the land surface temperature compared with urban region and the barren regionThe non‐radiative effect generally explains more than 50% of the local changes in land surface temperatureThe interactive canopies enlarge the changes in Ts for conversions from short vegetation to tall vegetation or urban to vegetation [ABSTRACT FROM AUTHOR]

Surface albedo is a crucial parameter in land surface radiation budget. As bias exists between the model simulated and observed surface albedo, data assimilation is an important method to improve the simulation results. Moreover, surface albedo is associated with the wavelength of the sunlight. So, solar radiation partitioning is important to parameterize the surface albedo. In this paper, the moderate resolution imaging spectroradiometer- (MODIS-) retrieved direct visible, direct near-infrared, diffuse visible, and diffuse near-infrared surface albedos were assimilated into the integrated urban land model (IUM). The solar radiation partitioning method was introduced to parameterize the surface albedo. Based on the albedo data from MODIS and the solar radiation partitioning method, the surface albedo data set for the Beijing municipal area was generated. Based on the surface albedo data set and the IUM, the impacts of the surface albedo on the surface radiation budget were discussed quantitatively. Surface albedo is inversely proportional to the net radiation. For urban areas, after assimilation, the annual average net radiation decreases about 5.6%. For cropland, grassland, and forest areas, after assimilation, the annual average net radiations increase about 20.2%, 24.3%, and 18.7%, respectively. [ABSTRACT FROM AUTHOR]

Fengyun-4A is the new generation of Chinese geostationary meteorological satellites. Land surface albedo, land surface emissivity and land surface temperature are key states for land surface modelling. In this paper, the land surface albedo, land surface emissivity and land surface temperature data from Fengyun-4A were assimilated into the Integrated Urban land Model. The Fengyun-4A data are one of the data sources for the land data assimilation system which devoted to produce the high spatial and temporal resolution, multiple parameters near real-time land data sets. The Moderate-Resolution Imaging Spectroradiometer (MODIS) LSA and LSE data, the Institute of Atmospheric Physics, China Academy of Sciences (IAP) 325 m tower observation data and the observed 5 cm and 10 cm soil temperature data in more than 100 sites are used for validation. The results indicate the MODIS land surface albedo is much smaller than the Fengyun-4A and is superior to the Fengyun-4A for the Institute of Atmospheric Physics, China Academy of Sciences 325 m tower site. The Moderate-Resolution Imaging Spectroradiometer land surface emissivity is smaller than the Fengyun-4A in barren land surface and the differences is relatively small for other land use and land cover categories. In most regions of the research area, the Fengyun-4A land surface albedo and land surface emissivity are larger than those of the simulations. After the land surface albedo assimilation, in most regions the simulated net radiation was decreased. After the land surface emissivity assimilation, in most regions the simulated net radiation was increased. After the land surface temperature assimilation, the biases of the land surface temperature were decreased apparently; the biases of the daily average 5 cm and 10 cm soil temperature were decreased. [ABSTRACT FROM AUTHOR]

Surface albedo is one of the key parameters of land surface radiation and energy balance. As surface albedoes for visible and near-infrared solar radiation are quite different, solar radiation partitioning is important to parameterize the total surface albedo and upward solar radiation. In this paper, a surface albedo parameterization scheme was introduced and a solar radiation partitioning method was developed to improve the simulation of the upward solar radiation. The simulation results were validated in a hinterland site of the Taklimakan Desert. The surface albedo is not only associated with the soil moisture, but associated with the solar zenith angle. The solar radiation partitioning method considers the joint influences of cloud cover, near-surface air pressure, and solar zenith angle and was compared with the method using the Simple Biosphere Model version 3 (SiB3). The total albedo depends on the partitioning of the total visible and near-infrared radiations. The results indicate the surface albedo parameterization scheme is important to parameterize the upward solar radiation. The new solar radiation partitioning method could improve the simulation result. [ABSTRACT FROM AUTHOR]

We present a method for the fast computation of the intersection between a ray and the geometry of a scene. The scene geometry is simplified with a 2D array of voxelizations computed from different directions, sampling the space of all possible directions. The 2D array of voxelizations is compressed using a vector quantization approach. The ray-scene intersection is approximated using the voxelization whose rows are most closely aligned with the ray. The voxelization row that contains the ray is looked up, the row is truncated to the extent of the ray using bit operations, and a truncated row with non-zero bits indicates that the ray intersects the scene. We support dynamic scenes with rigidly moving objects by building a separate 2D array of voxelizations for each type of object, and by using the same 2D array of voxelizations for all instances of an object type. We support complex dynamic scenes and scenes with deforming geometry by computing and rotating a single voxelization on the fly. We demonstrate the benefits of our method in the context of interactive rendering of scenes with thousands of moving lights, where we compare our method to ray tracing, to conventional shadow mapping, and to imperfect shadow maps. [ABSTRACT FROM AUTHOR]

Land surface evaporation is not only an important parameter in natural land surface modeling, but a crucial important parameter in urban hydrology modeling. A whole-layer soil evaporation scheme was developed in the integrated urban land model (IUM) to improve the soil evaporation simulation. The impervious surface evaporation (ISE) was used as a component of urban water balance equation. In this paper, the integrated urban land model was validated at one desert site and six urban road sites to emphasize the improvement in the evaporation simulations for arid and urban areas. A sensitivity analysis was implemented in seven basins to expand the utility of the whole layer soil evaporation scheme. For the urban road sites, the validation results indicate that imperious surface evaporation (ISE) plays a crucial role in road surface temperature (RST) simulations on rainy days. For the desert site, the validation results show that the inner layer evaporation is very important in arid regions. For the basins, the analysis results indicate that the relative monthly mean differences in the evapotranspiration (ET) between the simulations with (IUM) and without (Common Land Model (CoLM)) considering the inner layer evaporation range from −8% to 8%, which is proportional to the degree of dryness. In arid areas, especially deserts, the inner layer soil evaporation could not be neglected. [ABSTRACT FROM AUTHOR]

A fine-scale numerical model for road surface parameters prediction (BJ-ROME) is developed based on the Common Land Model. The model is validated using in situ observation data measured by the ROSA road weather stations of Vaisala Company, Finland. BJ-ROME not only takes into account road surface factors, such as imperviousness, relatively low albedo, high heat capacity, and high heat conductivity, but also considers the influence of urban anthropogenic heat, impervious surface evaporation, and urban land-use/land-cover changes. The forecast time span and the update interval of BJ-ROME in vocational operation are 24 and 3 h, respectively. The validation results indicate that BJ-ROME can successfully simulate the diurnal variation of road surface temperature both under clear-sky and rainfall conditions. BJ-ROME can simulate road water and snow depth well if the artificial removing was considered. Road surface energy balance in rainy days is quite different from that in clear-sky conditions. Road evaporation could not be neglected in road surface water cycle research. The results of sensitivity analysis show solar radiation correction coefficient, asphalt depth, and asphalt heat conductivity are important parameters in road interface temperatures simulation. The prediction results could be used as a reference of maintenance decision support system to mitigate the traffic jam and urban water logging especially in large cities. [ABSTRACT FROM AUTHOR]

Seasonal snow plays an important part in Earth's climate system. Snow cover regulates the land surface energy balance through altering the albedo of the land surface. To utilize the satellite-retrieved snow cover fraction (SCF) and snow depth (SD) data sufficiently and avoid inconsistency, this paper developed a very simple but robust quality control method to assimilate Fengyun satellite-retrieved SCF and SD simultaneously. The results show that the assimilation method which this paper implemented can not only utilize the satellite-retrieved SCF and SD data sufficiently but also avoid the inconsistency of them. Two experiments were designed and performed to quantify the impacts of snow on land surface energy balance using the integrated urban land model. With the increase of the SCF and SD, the net radiation decreased significantly during the day and increased a little at night; the sensible heat flux decreased significantly during the day; the evapotranspiration and ground heat flux decreased during the day too. [ABSTRACT FROM AUTHOR]

In a surface urban heat island (SUHI), the urban land surface temperature (LST) is usually higher than the temperature of the surrounding rural areas due to human activities and surface characteristics. Because a SUHI has many adverse impacts on urban environment and human health, SUHI mitigation strategies are very important. This paper investigates the mechanism of a SUHI based on the basic physical laws that control the formation of a SUHI; five mitigation strategies are proposed, namely: sprinkling and watering; paving a pervious surface; reducing the anthropogenic heat (AH) release; using a 'white roof'; increasing the fractional vegetation cover or leaf area index (LAI). To quantify the effect of these mitigation strategies, 26 sets of experiments are designed and implemented by running the integrated urban land model (IUM). The results of the sensitivity analysis indicate that sprinkling and watering is an effective measure for mitigating a SUHI for an entire day. Decreasing the AH release is also useful for both night- and daytime SUHI mitigation; however, the cooling extent is proportional to the diurnal cycle of AH. Increasing the albedo can reduce the LST in the daytime, especially when the solar radiation is significant; the cooling extent is approximately proportional to the diurnal cycle of the net radiation. Increasing the pervious surface percentage can mitigate the SUHI especially in the daytime. Increasing the fractional vegetation cover can mitigate the SUHI in the daytime but may aggravate the SUHI at night. [ABSTRACT FROM AUTHOR]

An integrated urban land model (IUM) was developed based on the Common Land Model (CoLM). A whole layer soil evaporation parameterization scheme was developed to improve soil evaporation simulation especially in arid areas. For the urban underlying surface, the energy and water balance model were modified; urban land parameters such as the anthropogenic heat (AH), albedo, surface roughness length, imperious surface evaporation etc. were also reparameterized. IUM was validated and compared with CoLM and the urbanized high-resolution land data assimilation system (u-HRLDAS) in single and regional scale. The validation results indicate that IUM can improve the simulation of land surface parameters and land-atmosphere interaction fluxes. [ABSTRACT FROM AUTHOR]

We investigate the multiple attribute decision making problems with the hesitant triangular fuzzy information. Then, we have developed the hesitant triangular fuzzy Einstein correlated averaging (HTFECA) operator. The prominent characteristic of the operators is that they can not only consider the importance of the elements or their ordered positions, but also reflect the correlation among the elements or their ordered positions. We have applied the HTFECA operators to multiple attribute decision making for evaluating the wireless network security with hesitant triangular fuzzy information. Finally an illustrative example for evaluating the wireless network security has been given to show the developed method. [ABSTRACT FROM AUTHOR]

This paper uses an urbanized high-resolution land data assimilation system (u-HRLDAS) to parameterize the urban land surface characteristics. The u-HRLDAS model is localized and developed in order to satisfy the need of the weather forecast in Beijing, China. The remote sensing data used to localize and drive u-HRLDAS include the soil type data and MODIS retrieved leaf area index (LAI) data. The evaporation and water depth for impervious surface in urban area are developed to improve the simulation of u-HRLDAS. The result of the urban weather forecast is used for the comparison based on the rapid update cycle system at Beijing Meteorological Bureau (BJ-RUC) without coupled with u-HRLDAS. The land surface temperature, land surface fluxes, and first layer soil moisture in several single sites and urban Beijing region by BJ-RUC are compared with u-HRLDAS after localization and development. The off-line simulation results indicate that compared with BJ-RUC, after the localization and development, u-HRLDAS can improve the simulation of land surface parameters and fluxes definitely. [ABSTRACT FROM AUTHOR]

A variational data assimilation algorithm for assimilating the land surface temperature (LST) into the Common Land Model (CLM) was implemented using the land surface energy balance equation as the adjoint physical constraint. In this data assimilation algorithm, the evaporative fractions of the soil and canopy were adjusted according to the remotely sensed surface temperature observations. This paper developed a very simple analytical algorithm to characterize the errors' weighting matrices in the cost function. The leaf area index (LAI) retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) was also assimilated into CLM using the direct insertion method. The analysis results from the CLM with the LST assimilation algorithm compare well with MODIS and field observations for the Yucheng site, especially in daytime. On the basis of the histogram of the error of the LST, it can be concluded that after assimilation, the LST was greatly improved in comparison with the MODIS observations, especially in daytime. These results indicate that this surface temperature assimilation method is efficient and effective, even when only one time observational LST data point is available for each day, especially in daytime. The regional spatial patterns of evapotranspiration and soil surface moisture were also compared before assimilation on the basis of LAI data calculated using the empirical formula, before assimilation on the basis of MODIS LAI data, and after assimilation on the basis of MODIS LAI data. [ABSTRACT FROM AUTHOR]

Impervious surface temperature is a key parameter in impervious surface energy balance. Urban canopy models are now widely used to simulate impervious surface temperatures, but the physical assimilation method for the urban canopy model is still under development and the use of high temporal resolution observation data are limited. In this paper, a physical assimilation method was used to improve the simulation of the impervious surface temperature for the first time. A variational assimilation method was developed and coupled with the integrated urban land model, using the impervious surface energy balance equation as the adjoint physical constraint. The results showed that when the observed impervious surface temperature data of every timestep were assimilated into the integrated urban land model, the bias of the impervious surface temperature was reduced about 86 %. For the operational run, the observed data were assimilated twice per day, and the bias of the impervious surface temperature was reduced by about 78%. [ABSTRACT FROM AUTHOR]