Underlying Surface Temperature Research Articles

Decadal Predictability of Seasonal Temperature Distributions

AbstractDecadal predictions focus regularly on the predictability of single values, like means or extremes. In this study we investigate the prediction skill of the full underlying surface temperature distributions on global and European scales. We investigate initialized hindcast simulations of the Max Planck Institute Earth system model decadal prediction system and compare the distribution of seasonal daily temperatures with estimates of the climatology and uninitialized historical simulations. In the analysis we show that the initialized prediction system has advantages in particular in the North Atlantic area and allow so to make reliable predictions for the whole temperature spectrum for two to 10 years ahead. We also demonstrate that the capability of initialized climate predictions to predict the temperature distribution depends on the season.

A dataset of dryland ground temperature in typical small watersheds in the hilly areas of Central Sichuan Basin (1997-2021)

The underlying surface temperature (i.e. land surface temperature) and soil temperature at different depths are collectively referred to as ground temperature. The variations and variation rules of ground temperature comprehensively depict the exchange of energy and materials between the atmosphere and the land surface. Hence ground temperature is an important parameter for assessing soil thermal conditions. Located in the agro-ecological zone of subtropical Sichuan Basin, Sichuan Yanting Agro-ecosystem Research Station in Chinese National Ecosystem Research Network (also referred to as Yanting Station, code YGA) serves as an experimental observation and research platform of Agro-Ecosystem set by the Chinese Ecosystem Research Network (CERN) and the National Science and Technology Infrastructure Platform in this ecological region. This dataset is based on the long-term automatic station observation data and manual observation data of the comprehensive meteorological observation field of Yanting Station. It consists of four data files, namely, hourly ground temperature data from the automatic observation stations on a daily basis (1997-2021), daily ground temperature statistical data from the automatic observation stations (2004-2021), monthly statistical data of ground temperature from the automatic observation stations (2004-2021) and daily and monthly surface temperature data form the manual observation stations (2004-2021). The data volume is about 8.85 MB. Ground temperature is the networked observation index of field stations. Observation instruments, data acquisition procedures, and data quality control adhere to standardized norms and protocols, ensuring the utmost reliability and comparability of ground temperature data. The accumulation of long time series and multi-level geothermal data can provide scientific data support for the energy and material exchange of ecosystem, the response to environmental change, and the application research of cultivated land quality assessment and food security in the main agricultural areas of the basin.

Potential Climate Impacts of Reforestation and Waterlogging in Belarus

The article discusses the expected climate changes in Belarus as a result of two types of land transformation – rewetting degraded peatlands and increasing forest cover. The analysis was performed for the growing season (May–September) based on long-term Earth remote sensing data, mesoscale modeling of atmospheric processes, and balance calculations using ERA5 reanalysis. It is shown that as a result of waterlogging, the daytime temperature of the underlying surface for the southern part of Belarus (below the latitude of Minsk) decreases within 1.5°С due to increased consumption, and for the northern part – within 0.5°С due to albedo regularity. At night, waterlogging, depending on the soil and climatic conditions, can cause both an increase and a specific value of the underlying surface temperature within 1°C. Evapotranspiration due to waterlogging in the northern regions of Belarus, and in the southern regions – emissions, which is associated with a significant ratio between consumption and transpiration in these regions. During the reforestation of cropland, the daytime land surface temperature of Belarus territory decreases within 2°C, and at night – within 0.4°C. The total evapotranspiration for the growing season due to the increase in forest cover reaches 100 mm, and approaching (maximum possible) consumption remains at the same level, which overestimates soil absorption at an increased amount of atmospheric pressure. The above changes in the physical characteristics of the underlying surface as a result of reclamation determine the standard surface air temperature in the reclamated disease within 0.4°C and an increase in the sums of atmospheric conditions within 2% of the climatic norm. At the same time, secondary reactions are predominantly distributed in morbidity due to western transfer with an emphasis on the eastern border distribution to the reclaimed region.

Hydrothermal conditions of southern and northern slope soils of northeastern Great Xing'an Mountain, China

The purpose of the article is to study the influence features of polar-oriented slopes on the near-surface energy and hydrothermal balance in the seasonal cryolithozone. The authors carried out a complex of field observations including measurement of air and underlying surface temperature, soil moisture, solar radiation and wind speed at the hydrological stations of Songling (southern slope) and Luoguhe (northern slope) in the northeast of the Great Xing'an Mountain (China). The analysis of the data obtained allowed to conclude that, on the one hand, the long-term influence of the thermal balance components causes significant differences in the soil structure and properties on differently oriented slopes. The number of daily freeze-thaw soil cycles on the southern slope (100 cycles) significantly exceeds the ones on the northern slope (56 cycles). The soil on the southern soil is 3 °C warmer than that on the northern slope, and its humidity in the area of the Songling hydrological station is lower than that at the Luoguhe station. On the other hand, differences in soil properties control the energy exchange between the atmosphere and the earth's surface, this means that the incoming short-wave solar radiation and heat flux into the soil on the southern slope is greater than on the northern one. Therefore, slope orientation is one of the significant environmental factors affecting the influx of solar energy, temperature and humidity of the soils in the northeastern Great Xing'an Mountain. It also has a decisive role for the spatial distribution and evolution of seasonal permafrost in the region and, accordingly, affects the stability and safety of engineering structures. The performed research is important for understanding the relationship between climate and frozen soil in the mountainous areas with seasonal cryolithozone as well as for optimization of boundary conditions when modeling rock freeze-thaw processes.

Combining microclimatic monitoring with questionnaires, for understanding thermal comfort in Linpan, a typical agricultural ecosystem settlement in the Chengdu plain

Linpan is a unique livable ecosystem settlement in western Chengdu, China, that has existed for thousands of years. However, its living environment is deteriorating because of rapid urbanization. Improving residents' satisfaction with environmental quality through providing favorable thermal comfort is of vital significance for preserving Linpan. However, whether the existing microclimate conditions in Linpan actually meet the inhabitants' thermal comfort is not yet known. Therefore, this study combines an objective microclimatic monitoring approach with a subjective questionnaire method, to quantify the thermal comfort, and in a further step to investigate its relationship with inhabitants' thermal adaptation and thermal environment, for the outdoor (including public spaces and courtyards), semi-outdoor (referring to the spaces under eaves) and indoor (referring to building interiors) spaces of Linpan. The results show that the neutral temperatures for outdoors and indoors are 26.64 °C and 26.84 °C, respectively. Air temperatures for all these four types of spaces exceed the inhabitants' thermal comfort. Microclimates are found to have strong influences on thermal comfort in Linpan: underlying surface temperature has the most influence on public spaces; air temperature is the important determinant for courtyards, the spaces under eaves and building interiors. Local residents have stronger preference for improving the air temperature, relative humidity and wind speed outdoors than indoors, because they can adapt better to the indoor environment. Our findings contribute to determining better ways of preserving the Linpan settlement by clearly understanding its thermal environment and thermal comfort requirements.

Комбинированное использование изображений Landsat 8 и Sentinel 2А для улучшения пространственного разрешения температуры поверхности Земли

Underlying surface temperature is an important parameter of underlying surface thermal radiation and can be used in monitoring forest fires, coal fires, urban thermal radiation and developing climate models. Ground-based observations provide temperature information for small areas around weather stations and in fact cannot provide a high density of surface temperature data. Remote sensing technologies are promising in this respect. However, due to the low spatial resolution in the infrared channel, the surface temperature calculated from Landsat and Aster images does not always have the required detail needed when studying small areas. The results of images from Sentinel 2A and Landsat 8 satellites combination (joint digital processing) made in order to increase spatial resolution of underlying surface temperature are presented. Comparison of surface temperature extreme values shows that in spite of small difference in extreme values of temperature, the spatial field of temperature in case of combined images was more detailed and variable. This is evidenced by a significant increase in the variability of the temperature standard deviation. Direct visual observations of image fragments also confirm that combining Sentinel 2A and Landsat 8 images increases the spatial resolution of the surface temperature when compared to the Landsat 8 image

Urban Micro-Scale Thermal Environment Simulation Supported by UAV Thermal Infrared Data

With further improvements to meet social requirements for healthy and comfortable living, the research of micro-scale thermal environments has been received increasing attention. The key to micro-scale thermal environment study is the underlying surface temperature field simulation, which requires high precision results. Taking a typical area of the Jiangning District, Nanjing City, as a study area, this study used a UAV equipped with a thermal infrared imager to obtain surface temperature data in summer and autumn because of the limitation of the traditional ground measurements. Then, the numerical simulation software of ENVI-met and PALM-4U were utilized to conduct the surface temperature filed simulation. The simulation results were further analyzed combined with measured data. The modeling results indicated that the numerical simulation has high spatial accuracy, which can be applied to the study of the urban micro-thermal environment. Furthermore, the simulation effect of the model on the artificial surface is better than that of the natural surface, and the simulation effect of the open surface is better than that of the non-open surface. The study also found that the simulation effect of ENVI-met under the influence of occlusion was better than that of PALM-4U. The vegetation occlusion PALM-4U was less effective than that of ENVI-met, although both models correctly predicted the ground temperature under the occlusion of buildings. The overall conclusion indicates that the applicability of ENVI-met is superior to that of PLAM-4U for urban micro-thermal environment simulation. The study can provide a reference for the high-resolution remote sensing research of urban micro-scale thermal environments.

Retrievals of High‐Latitude Surface Emissivity Across the Infrared From High‐Altitude Aircraft Flights

AbstractWe present retrievals of infrared spectral surface emissivities spanning the far infrared and mid‐infrared from aircraft observations over Greenland, taken at an altitude of 9.2 km above sea level. We describe the flight campaign, available measurements, and the retrieval method. The principal barriers to reducing uncertainty in the emissivity retrievals are found to be instrumental noise and our ability to simultaneously retrieve the underlying surface temperature. However, our results indicate that using the instrumentation available to us it is possible to retrieve emissivities from altitude with an uncertainty of ~0.02 or better across much of the infrared. They confirm that the far‐infrared emissivity of snow and ice surfaces can depart substantially from unity, reaching values as low as 0.9 between 400 and 450 cm−1. They also show good consistency with retrievals from the same flight made from near‐surface observations giving confidence in the methodology used and the results obtained for this more challenging viewing configuration. To the best of our knowledge, this is the first time that far‐infrared surface emissivity has been retrieved from altitude and demonstrates that the methodology has the potential to be extended to planned satellite far‐infrared missions.

The mitigation strategies for bottom environment of service-oriented public building from a micro-scale perspective: A case study in China

Abstract Ecological civilization construction has risen to be a major social concern in China so that green construction and low-carbon life have been advocated. However, the construction of urban micro-scale green space environment might not align well with the national policies, forming public space without people involved in, which caused an energy consumption rise of interior service-oriented public buildings with high-volume people. Therefore, this paper is aimed to explore suitable spatial structure and configuration in outdoor bottom environment to improve the site efficiency through field measurement and numerical simulation. The results show that, first, multi-layered greening system (MLGS) proposed might activate urban micro-scale green space with the public involved in, and the mean radiation temperature (MRT) declines 1-3 °C. Second, the integration of colonnade (semi-open space) + courtyards is suitable for exterior space of service-oriented public buildings with high-volume pedestrians under hot-humid climatic condition. Third, the ability of microclimate adjustment is sunshade > evaporation > grass ground. Finally, compared to grass, water-holding pavement has obvious cooling effect (lower 12 °C under sunlight and 8 °C under membrane structure) on underlying surface temperature.

СПЕКТРАЛЬНЫЕ ХАРАКТЕРИСТИКИ ТУНДРОВЫХ И ЛЕСОТУНДРОВЫХ ЛАНДШАФТОВ В ГОДЫ ЛЕТНИХ ТЕМПЕРАТУРНЫХ АНОМАЛИЙ

The warming at high latitudes, remaining in recent years, has a direct impact on arctic and subarctic landscapes. Possible changes of this landscapes under the climate warming are closely related with regulatory mechanisms for the underlying surface temperature. The circumstances of forming radiation and evapotranspirational regulatory mechanisms for the surface temperature were explored for tundra (from arctic to southern) and forest tundra landscapes of Novaya Zemlya and Western Siberia. The MODIS data of surface spectral characteristics were used, and more specifically albedo (Al) and surface temperature (Ts) for July 2000-2019. The work shows that the radiation regulatory mechanism of the surface temperature is dominated in glacial and polar desert landscapes of Arctic and Subarctic with a predominance of stony and rubble types of surfaces with lichens. At the same time, radiative surface temperature control mechanism in mountain and arctic tundra of Novaya Zemlya almost does not depend on weather anomalies and so far has a little implication for the temperature trend. In the mainland and forest tundra, the evapotranspirational regulatory mechanism for the surface temperature starts to prevail. This is supported by the increasing of monthly average air temperatures to 15-16°С, which is beneficial to the vegetation diversity. In subzones of the southern and forest tundra, the connection of albedo and surface temperature depends on altitudes, slope exposure and especially on extreme temperature anomalies. In basins, or hydromorphic complexes, in cold years against the backdrop of wetlands the regulatory mechanism for the surface temperature prevails, and in warm years the humidity decreasing leads to the highest vegetation development and the connection type can turn into the evapotranspirational one. On the high grounds the return process is observed, which is also connected with the changes in humidification conditions. In forest tundra, where the air temperature rises and the canopy height increases, the evapotranspirational mechanism of spectral parameters Al–Ts connections is weakening. As a result, in southern and forest tundra two balanced steady states of the connection types of surface spectral characteristics can exist in relation to lighting conditions and temperature anomalies.

The Variation Law of Different Underlying Surface Temperature and Urban Temperature

The rapid development of urbanization has changed the type of underlying surface within the city and affected the temperature changes in the city. Mastering the relationship between urban temperature and the temperature of the different underlying surface is the basis for improving the urban heat island effect. To this end, select the school with representative urban characteristics to study the relationship between urban temperature and urban underlying surface types under different weather conditions. The Chenggong Campus of Yunnan Normal University in Kunming, Yunnan Province is the typical urban research object. Extracting the underlying surface type data of four main active areas such as grassland, water surface, bare soil and asphalt by means of artificial field measurement, and analyzed. The experimental results show that under different underlying conditions, the influence of environmental climatic conditions on urban temperature is different. This shows that in urban planning, the rational planning and design of different underlying surface types can effectively solve the urban heat island and rain island effect problem.

Оценка тепловых карт подстилающей поверхности на участках вырубок по данным Landsat

Оценка тепловых карт подстилающей поверхности на участках вырубок по данным Landsat

Radiometric microwave field measurements of the complex dielectric constant of the water surface

The paper describes the new remote method of radiometric in situ measurements of the real and imaginary parts of the dielectric constant (permittivity) of the underlying sea surface, which is an important parameter for remote sensing of the Earth. The method does not require absolute calibration of a radiometer, but uses the black body with the underlying surface temperature, which simplifies the measurement and allows one to measure the effective reflection coefficient at specified polarizations. It is shown that, for a fixed value of the reflection coefficient in sensing to the nadir, R(θ = 0°) = const, the reflection coefficient at the horizontal polarization is almost independent of the of dielectric loss angle. The reflection coefficient at the vertical polarization is most sensitive to the loss angle in the vicinity of the Brewster angle Rv(θ = θBr). The paper presents the results of measurements of the sea surface reflection coefficient using the radiometer operating at frequency of 37.5 GHz. The reflection coefficients at vertical and horizontal polarizations are calculated taking into account the antenna pattern and the distribution of slopes of a weakly roughened sea surface. The paper presents the example of determining the real and imaginary parts of the permittivity based on experimentally measured values of reflection coefficients at incidence angles close to the nadir and the reflection coefficient Rv(θ = θBr) at the Brewster angle. The obtained experimental values correspond to the theory within the limits of diversity of existing models.

Atmospheric Processes in the South Baikal Basin and Their Role in Relief Formation

Climatic conditions and the solar and circulation features in the Lake Baikal basin are analyzed. The relationship between the heat balance and surface temperature of slopes is shown, taking into account each features’ physical state. The dependence of the heat balance values and the underlying surface temperature were revealed. The quantitative material allowed us to reveal regional patterns of geomorphological regimes, seasonal rhythm, and the dynamics of processes. In Cisbaikalia, within the denudation cycle, semi-humid states under water erosion and aeolian processes of moderate intensity predominate. The semi-arid state manifests itself under decreasing humidification. In these years, the probability of extreme manifestations of aeolian processes is high. The humid states occur in 1% of cases, primarily in extremely wet years, when fluvial processes are dramatically activated. In Cisbaikalia, climate warming and an increase in mean annual temperature have been observed in recent years. Depending on the moisture amplitude and heat availability, the intensity and direction of water erosion and aeolian processes is changing now. The dynamics of relief-forming processes cause an increase in loose substance in the lake and the exacerbation of the ecological situation.

Study on the thermal performance and wind environment in a residential community

In situ measurements are conducted on the thermal performance and wind environment in a residential community. The relationship between the community thermal performance and the tested parameters including the air temperature, relative humidity, underlying surface temperature is also presented. The results indicate that the lawns and tree shade in the community help to reduce the ambient temperature and enhance the relative humidity which means that the green ratio of a building cluster makes a significant contribution to the thermal performance. Furthermore, a numerical simulation is performed with the experimental results as the boundary conditions to get the airflow field and pressure field of the whole community to improve the architectural layout. The numerical results indicate that staggered arrangement of the building groups seems to be more beneficial to eliminating the laneway wind effects compared to aligned arrangement.

Mapping urban heat islands of arctic cities using combined data on field measurements and satellite images based on the example of the city of Apatity (Murmansk Oblast)

This article presents the results of a study of the urban heat island (UHI) in the city of Apatity during winter that were obtained according to the data of field meteorological measurements and satellite images. Calculations of the surface layer temperature have been made based on the surface temperature data obtained from satellite images. The experimental data on air temperature were obtained as a result of expeditionary meteorological observations, and the experimental data on surface temperature were obtained based on the data of the space hyperspectral Moderate-Resolution Imaging Spectroradiometer (MODIS) system, channels 31 and 32 (10.78–11.28 and 11.77–12.27 micrometers, respectively). As a result of the analysis of temperature fields, an intensive heat island (up to 3.2°C) has been identified that was estimated based on the underlying surface temperature, and its mean intensity over the observation period significantly exceeds the representative data for European cities in winter. It has also been established that the air temperature calculated according to the MODIS data is systematically higher under winter conditions than the air temperature from direct measurement data.

Radiative and Microphysical Properties of Cirrus Cloud Inferred from Infrared Measurements Made by the Moderate Resolution Imaging Spectroradiometer (MODIS). Part I: Retrieval Method

AbstractAn optimal estimation–based algorithm is developed to infer the global-scale distribution of cirrus cloud radiative and microphysical properties from the measurements made by the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) at three infrared (IR) window bands centered at 8.5, 11, and 12 μm. Cloud-top and underlying surface temperatures, as a priori information, are obtained from the MODIS operational products. A fast-forward model based on semianalytical equations for the brightness temperature is used. The modeling errors in brightness temperature are mainly from the uncertainties in model parameters including surface emissivity, precipitable water, and cloud-base temperature. The total measurement–model errors are well correlated for the three bands, which are considered in the retrieval. The most important factors for the accurate retrieval of cloud optical thickness and the effective particle radius are cloud-top and surface temperatures, whereas model parameter uncertainties constitute a moderately significant error source. The three-band IR method is suitable for retrieving optical thickness and effective radius for cloud optical thicknesses within a range of 0.5–6, where the typical root-mean-square error is less than 20% in optical thickness and less than 40% in effective particle radius. A tropical-region case study demonstrates the advantages of the method—in particular, the ability to be applied to more pixels in optically thin cirrus in comparison with a solar-reflection-based method—and the ability of the optimal estimation framework to produce useful diagnostics of the retrieval quality. Collocated comparisons with spaceborne active remote sensing data exhibit reasonable consistency with respect to retrieved particle size.

Possibilities for determining temperature and emissivity of the land surface from data of satellite IR sounders with high spectral resolution (IRFS-2)

Numerical experiments on the simultaneous retrieval of the temperature and spectral emissivity of different land types are performed on the basis of inversion of the simulated high spectral resolution measurements by the IRFS-2 satellite IR sounder. The IRFS-2 data inversion method is based on using a priori information on the spectral behavior of emissivity of different land types and the multiple linear regression technique. The rms errors of determination of the underlying surface temperature using different solving operators are 0.26–0.71 K. The application of the developed IRFS-2 measurement inversion method makes it possible to estimate the land surface emissivity with an rms error not larger than 0.015.

Modeling water and heat balance components for the river basin using remote sensing data on underlying surface characteristics

The method of the AVHRR-3 (NOAA) radiometer measurement data subject processing is produced for the retrieval of underlying surface temperature and several vegetation characteristics under cloud-free conditions. A technology for deriving the values of these parameters from the MODIS (EOS/Terra and Aqua) radiometer data is developed. The estimation of the temperature and vegetation characteristics is carried out for the Seim River basin (Kursk region) with the catchment area of 7460 km2 for 2003–2005 vegetation seasons. Practical coincidence of estimations of AVHRR- and MODIS-derived temperatures, as well as the coincidence with ground observation results, is revealed. Statistics of these estimation errors is analyzed. Satellite-derived estimations of land surface temperature (LST) and vegetation characteristics are used for the calibration and verification of the developed model of the vertical heat and water transfer in the soil-vegetation-atmosphere system (SVAT). The model is intended for calculations of evapotranspiration, soil water and heat content, latent and sensible heat fluxes, and other water and heat balance components. The abilities to compute these parameters using the satellite estimations of the leaf area index and projective vegetation cover fraction as the model parameters and LST satellite estimations as the model input variable are investigated.

ATMOSPHERIC PARAMETERS OVER THE MARGINAL ICE ZONE RETREIVAL FROM ANSR/AMSR-E DATA

A direct radiative transfer model, 478 radiosondes complimented by the cloud liquid water content profiles and the underlying surface temperatures and emissivities were used to simulate the brightness temperatures TBs over the Marginal Ice Zone at ADEOS-II AMSR and Aqua AMSR-E frequencies. The precipitable water V varied from 0.63 to 18.5kg/m2, the total cloud liquid water content Q£0.25kg/m2 and SST£1°C. The mean experimental values of emissivity and its fluctuations for several types of the first-year ice at ice temperature of 263 to 271K were used in a model. The sea surface emissivity was computed taking into account wind action. 10 values of ice concentration C uniformly distributed from 0.0 to 1.0 were selected for each radiosonde. The radiometer noises of 0.5K were added to the modeled TBs. Standard regression techniques were applied to retrieve V, Q and C from the simulated TBs with vertical and horizontal polarization at 18.7, 23.8 and 36.5GHz. The retrieval errors increase from »0.5 to »1.7kg/m2 for V and from »0.02 to »0.06 kg/m2 for Q with the increase of C from 0.0-0.3 to 0.7-1.0. The algorithms were used to retrieve V, Q and C in the Okhotsk Sea from the TBs measured by AMSR-E