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The article presents selected results of the assessment of the harmfulness of building vibrations and the impact of railway traffic on people staying in buildings. The research presented in the article concerns a long-term field study. Field research was conducted in various locations and with the movement of various types of rolling stock. The results were the basis for determining the zones of influence of railway vibrations on the building structure. The criteria adopted in the research were the conditions of the impact of vibrations on the structure of buildings as well as the vibration comfort for people staying in buildings and passively perceiving vibrations. The paper presents the methodology of field research and selected results from the conducted research. The proposed zones vary depending on the type of trains (freight and passenger). The range of zones also depends on the structure of the building and human perception of passively perceived vibrations. All analyses carried out for the purposes of this work are in accordance with Polish regulations and were performed by an accredited laboratory for testing vibrations and deformations of buildings. The proposed zones were adopted for use in design and diagnostic practice regarding the impact of vibrations on buildings and people in buildings.

Coastal seas are under increasing pressure from extreme weather events and sea level rise, resulting in impacts such as changing hydrodynamic conditions, coastal erosion, and marine heat waves. To monitor changes in coastal marine habitats, such as reefs and macrophytes meadows, which add to the resilience of our coasts, consistent, medium- to long-term seafloor observations are needed. This project aims to deliver repeated, high-frequency sonar surveys on a stationary seabed mooring of a specific target area over a period of up to several months. A new stand-alone subsea system, the Sonarlogger, based on a battery pack, low-power logger and a high-resolution scanning sonar, was developed. It allows for long-term deployments with a customisable battery pack, WI-FI download and configurable sleep state. The system has been tested for over 130 days in dynamic coastal environments off the Belgian coast. Combined with auxiliary sensors, such as for measuring currents, waves and turbidity, this system enables comprehensive studies of morphologic changes and changing benthic ecosystems. Moreover, this system has the capacity to provide measurements of coastal environments during storms, where conventional systems may fall short, providing insights into event-based changes of the seafloor.

To obtain new information about surface waves, it is proposed to use an underwater acoustic wave gauge, and an assessment of its effectiveness can be performed using a numerical simulation and field experiment. A new device, an underwater acoustic wave gauge named "Kalmar", was developed by the Institute of Applied Physics of the Russian Academy of Sciences for long-term, all-weather monitoring of wind waves. The instrument uses ultrasound to probe the water surface from underwater and can be used to verify remote sensing data. In this work, the capabilities of the device are tested and compared with ADCP data. Two independent methods for processing underwater acoustic wave gauge data are discussed and compared. One of them is completely new for acoustic measurements and is based on the analysis of the shape of the reflected acoustic pulse averaged over space and time. The other allows processing individual reflected pulses and calculating the time implementation of the distance to the water surface. It is shown that two independent methods of significant wave height retrieval from the acoustic wave gauge measurements are highly correlated. The "Kalmar" acoustic wave gauge and the RDI WH-600 acoustic Doppler current profiler operated simultaneously at the test site in Gelendzhik from 1 February to 10 February 2020. The significant wave heights measured by the two instruments are in good agreement. [ABSTRACT FROM AUTHOR]

Currently, there is no methodological support for radiation monitoring and sanitary and epidemiological assessment of radon concentration (or radon EEC) and other parameters of the radiation situation in existing operated buildings. The paper presents a review of the protocols for conducting measurements of indoor Leningrad region with previously found elevated levels of radon concentration using long-term measurements. The survey revealed that highest values of indoor radon ECC were obtained using instant measurements in several educational institutions both in the normal operation mode of the buildings (up to 1106 Bq/m3) and after leaving the premises for 12 hours with closed windows and doors (up to 1586 Bq/m3) according to the requirements of paragraph 6.5 of MU 2.6.1.2838-11. High values of radon concentration were also obtained using long-term and short-term measurements (up to 4900 and 1420 Bq/m3, respectively). In addition, high values of radon flux density were detected (up to 2030 mBq/(m2·s)). The established hygienic norms for ambient dose equivalent rate indoors and outdoors were not exceeded in the surveyed educational institutions. The levels of gross alphaand beta activities in tap water sampled from the surveyed educational institutions were below the control levels, and an exceedance of intervention level for activity concentration of radon in analyzed samples was not detected. The results of the survey will be used for hygienic assessment of doses and health risks for students (pupils) and employees of several educational institutions of the Leningrad region due to exposure to radon and its progeny and can be used to improve the method for indoor radon concentration monitoring in existing operated public buildings in the Russian Federation, which in turn will make it possible to obtain correct values of public doses and health risks.

This paper reports on the location of sources contributing to a point flux measurement in the southern taiga, Russia. The measurement tower is surrounded by a coniferous forest with a mean aerodynamically active height of 27 m (h). Aerodynamical parameters of the forest, such as displacement height d and aerodynamic roughness z 0 , derived from wind speed profile measurements for 2017–2019, were used to estimate the seasonal and daily behavior of the flux footprint. Two analytical footprint models driven by d and z0 were used to estimate the footprint for canopy sources. The Lagrangian simulation (LS) approach driven by flow statistics from measurements and modeling was used to estimate the footprint for ground-located sources. The Flux Footprint Prediction (FFP) tool for assessing canopy flux footprint applied as the option in the EddyPro v.7 software was inspected against analytical and LS methods. For model comparisons, two parameters from estimated footprint functions were used: the upwind distance (fetch) of the peak contribution in the measured flux (Xmax) and the fetch that contributed to 80% of the total flux (CF80). The study shows that Xmax varies slightly with season but relies on wind direction and time of day. All methods yield different Xmax values but fall in the same range (60–130 m, around 2–5 h); thus, they can estimate the maximum influence distance with similar confidence. The CF80 values provided by the FFP tool are significantly lower than the CF80 values from other methods. For instance, the FFP tool estimates a CF80 of about 200 m (7 h), whereas other methods estimate a range of 600–1100 m (25–40 h). The study emphasizes that estimating the ground source footprint requires either the LS method or more complex approaches based on Computational Fluid Dynamics (CFD) techniques. These findings have essential implications in interpreting eddy-flux measurements over the quasi-homogeneous forest. [ABSTRACT FROM AUTHOR]

To obtain new information about surface waves, it is proposed to use an underwater acoustic wave gauge, and an assessment of its effectiveness can be performed using a numerical simulation and field experiment. A new device, an underwater acoustic wave gauge named “Kalmar”, was developed by the Institute of Applied Physics of the Russian Academy of Sciences for long-term, all-weather monitoring of wind waves. The instrument uses ultrasound to probe the water surface from underwater and can be used to verify remote sensing data. In this work, the capabilities of the device are tested and compared with ADCP data. Two independent methods for processing underwater acoustic wave gauge data are discussed and compared. One of them is completely new for acoustic measurements and is based on the analysis of the shape of the reflected acoustic pulse averaged over space and time. The other allows processing individual reflected pulses and calculating the time implementation of the distance to the water surface. It is shown that two independent methods of significant wave height retrieval from the acoustic wave gauge measurements are highly correlated. The “Kalmar” acoustic wave gauge and the RDI WH-600 acoustic Doppler current profiler operated simultaneously at the test site in Gelendzhik from 1 February to 10 February 2020. The significant wave heights measured by the two instruments are in good agreement.

The measurement of the CO2 concentration has a wide range of applications. Traditionally, it has been used to assess air quality, with other applications linked to the experimental assessment of occupancy patterns and air renewal rates. More recently, the worldwide dissemination of COVID-19 establishing a relationship between infection risk and the mean CO2 level has abruptly led to the measurement of the CO2 concentration in order to limit the spread of this respiratory disease in the indoor environment. Therefore, the extensive application of this measurement outside of traditional air quality assessment requires an in-depth analysis of the suitability of these sensors for such modern applications. This paper discusses the performance of an array of commercial wall-mounted CO2 sensors, focusing on their application to obtain occupancy patterns and air renovation rates. This study is supported by several long-term test campaigns conducted in an in-use office building located in south-eastern Spain. The results show a spread of 19–101 ppm, with a drift of 28 ppm over 5 years, an offset of 2–301 ppm and fluctuations up to 80 ppm in instantaneous measurements not related to concentration changes. It is proposed that values averaged over 30 min, using a suitable reference value, be used to avoid erroneous results when calibration is not feasible. [ABSTRACT FROM AUTHOR]

We present ground‐based microwave measurements of mesospheric water vapor made by the Water Vapor Millimeter‐wave Spectrometer (WVMS) instruments since the early 1990s from sites in California, Hawaii, and New Zealand. These measurements are compared with coincident measurements from the Halogen Occultation Experiment, the Aura Microwave Limb Sounder, and Sounding of the Atmosphere using Broadband Emission Radiometry; all of which combine to cover the entire time period of the ground‐based measurements. Comparisons are presented both on ∼weekly timescales in order to better identify discontinuities in the relative differences and on annual timescales in order to better study geophysical variations. The WVMS retrievals shown here are available on the Network for the Detection of Atmospheric Composition Change database. The range of WVMS trends and the differences from the satellite trends, with the latter varying over a range of ∼3%/decade, provide an estimate of how accurately it would be possible to determine multidecadal trends using ground‐based microwave instruments in a postsatellite era. This uncertainty is comparable to the trend in mesospheric water vapor that is expected to have occurred since the early 1990s. Plain Language Summary: Understanding long‐term trends in water vapor in the middle atmosphere (the atmosphere from about 20 to 80 km) is important because increases in water vapor can cause additional ozone depletion and there are indications that variations in middle atmospheric water vapor may affect global surface climate. Increases in water vapor in the middle atmosphere are caused by increasing anthropogenic methane emissions, but changes are also caused by other factors, such as variations in tropical tropopause (the boundary that separates the troposphere from the stratosphere) temperatures. These temperatures are important because as air moves upward from the troposphere to the stratosphere the very cold temperatures at the tropopause freeze dry most of the water from the rising air. This study focuses on ground‐based microwave spectrometers that have been measuring water vapor in the middle atmosphere from three sites since the early 1990s. We provide both an estimate of the trend since then and, based on comparisons with satellite data, an estimate of the uncertainty of the trend from these ground‐based instruments. Understanding the uncertainty of this trend is important given the unfortunate likelihood that satellite measurements of middle atmospheric water vapor will be unavailable in future decades. Key Points: We present measurements of mesospheric water vapor since the early 1990s from three sites and compare with three satellite data setsTrend and trend uncertainty estimates are presentedWe document the effect of the solar cycle on these mesospheric water vapor measurements [ABSTRACT FROM AUTHOR]

Annual environmental noise monitoring is a legal requirement for local self-governments in the Republic of Serbia. However, Serbian legislation does not stipulate specific monitoring procedures, so each local self-government unit has to create its own environmental monitoring program within its jurisdiction. This paper analyzes the reliability of noise monitoring programs in local self-government units, based on short-term measurements. The reliability of applicable environmental noise monitoring programs in Serbia was examined by simulating the program imlementation to the results of noise monitoring obtained through continuous measurement over a period of one year. The above mentioned simulation showed that the monitoring programs based on short-term monthly measurements and a measurement time interval over 24 hours have the best repeatability and reliability result, especially at locations with the same daily noise profile and the occasional occurrence of unexpected short-term noise events. The results obtained in this study indicated that, either with higher or lower degrees of reliability, other programs can be used to monitor noise at measurement points near major urban roads with heavy and relatively constant vehicle flow throughout the day.

The relationship between the dynamics of the atmospheric pollutants and meteorological conditions has been analyzed during the COVID-19 pandemic in Moscow in spring, 2020. The decrease in traffic emissions during the lockdown periods from March 30th until June 8th played an important role in the decrease (up to 70%) of many gaseous species and aerosol PM10 concentrations and in the increase of surface ozone (up to 18%). The analysis of the pollutant concentrations during the lockdown showed much smoother diurnal cycle for most of the species due to the reduced intensity of traffic, especially during rush hours, compared with that before and after the lockdown. The specific meteorological conditions with low temperatures during the lockdown periods as well as the observed smoke air advection have made a considerable contribution to the air quality. After removing the cases with smoke air advection the decrease in concentration of many pollutants was observed, especially in NOx and PM10. The analysis of Pearson partial correlation coefficients with fixed temperature factor has revealed a statistically significant negative correlation between the Yandex self-isolation indices (SII), which can be used as a proxy of traffic intensity, and daily concentrations of all pollutants, except surface ozone, which has a statistically significant positive correlation with SII caused by specific photochemical reactions. In situations with SII>2.5 more favorable conditions for surface ozone generation were observed due to smaller NOx and the higher O3 /NOx ratios at the same ratio of VOC/NOx. In addition, this may also happen, since during the Arctic air advection, which was often observed during the lockdown period, the growth of ozone could be observed due to the downward flux of the ozone-rich air from the higher layers of the atmosphere.

The rapid growth of the wireless communication industry has resulted in the installation of numerous of base stations, everywhere in our surroundings. The population is exposed to Radio Frequency Electromagnetic Fields of varying frequency and strength. This, and introduction of new systems have risen public concerns regarding potential health effects from this RF-EMF exposure. The purpose of this project is to get an overview of any changes in exposure when new technologies are introduced. From June 2013 to October 2019, measurements were made at 16 measurement points in Kristiansand and surrounding areas in the same order, on the same day of the week and at the same time of day. The measurements are performed on the frequency bands 390, 450, 800, 900, 1800, 2100, 2400, and 2600 MHz. When we summed up the exposure for all the frequency bands relative to the limit values in a measuring point, the total values per measuring point showed that the exposure outdoors in most cases is less than 1‰ of the limit value. In 2017, a temporary increase was registered for most measurement points, but during 2018 the levels returned to the levels registered before 2017. During the increase, the levels were still low, around 3‰ of the limit values. The increase may be due to the fact that two mobile operators during this period made a comprehensive reconfiguration of their networks. The measurements presented in this report show that the exposure of the population is low, thousandths of the limit values, and relatively constant over time even though new technologies are introduced. [ABSTRACT FROM AUTHOR]

In the recent years, Digital Image Correlation (DIC) was applied with very promising results to monitor cracks in reinforced concrete structures. However, current DIC measurements present some limitations to characterize the existing crack (already present in the reference image) and for long-term monitoring due to the principles of the correlation algorithm. This paper presents two techniques to complement DIC in these two cases. The first one is based on direct detection using existing algorithms. The second one is based on the detection of markers fixed around the crack. Their relative position in different images is used to compute the crack displacement that occurred between the inspections. A conventional DIC set-up can be used for this technique. Simplified and refined methods are proposed to quantify the measurement uncertainty and to determine the number and position of markers. Both techniques are validated in laboratory conditions and in-situ in an existing concrete bridge. The combination of the two presented techniques with conventional DIC is promising and could be of interest for applications with complicated crack patterns where a detailed understanding of the crack kinematics is required. • A direct detection technique is validated to characterize existing cracks in reinforced concrete structures. • A marker-based technique is proposed for long term monitoring of cracks in existing concrete structures. • The techniques are validated in laboratory conditions and in an existing prestressed concrete bridge. • Limits of applicability and recommendations are provided for both techniques based on the performed validation tests. [ABSTRACT FROM AUTHOR]

Ammonia and greenhouse gases have a negative impact on the environment. The most important agricultural sources of ammonia are dairy cattle housing systems, which are mainly naturally ventilated. Estimating emissions for naturally ventilated barns (NVB) is challenging due to the large number of influencing factors. Most notably, the direct coupling of the inside flow regime with ambient and turbulent weather conditions causes difficulties in measuring ventilation rates, gas concentrations and emissions; thus, different methods are available. In this study, we compared the outputs of total volume flow obtained by two indirect methods (CO 2 mass balance) to the direct method. The latter we assume in this study as the reference method since it is a fundamental approach that estimates airflow on the inlet. In the context of mass balancing, we compared wind related (sampling method 1) and non-wind related (sampling method 2) approaches for measuring CO 2 concentrations. The total volume flow calculations were based on hourly measurements of CO 2 concentrations obtained by Fourier transform infrared (FTIR) spectrometer. Data were collected over a period of six months. The values of the total volume flow were filtered for prevailing southern winds (90 ∘ angle). The wind related method (sampling method 1) in stable cross-inflow conditions produces more accurate and realistic values in terms of the general representation of the values in comparison with direct method and can be considered further for measurements of volume flow in the NVBs. [ABSTRACT FROM AUTHOR]

Interannual variability of the Atlantic inflow (AI) into the Nordic Seas is studied using moored current and temperature measurements in the Norwegian Atlantic Current during the 25‐year period 1995–2020. We show that the properties of the AI are strongly connected to the dynamics of the Northern Atlantic and demonstrate the robustness of the average winter wind field in driving the variability with 3‐month winter maxima in the range of (40–50) cms−1. In that sense, the zero‐wind‐stress‐curl (ZWSC)‐lines aligned northeastward are crucial. Occasional events with slowdown of winter‐maxima are connected to a meridional and zonal shift of the ZWSC‐lines, and not the strength of the wind. This is manifested in a correlation of 0.3 versus the North Atlantic Oscillation (NAO) winter‐index, demonstrating that the NAO‐index is insufficient to explain the AI‐variability. The records show no long‐term‐trend over the 25‐year period 1995–2020, regarding volume flux, temperature, nor temperature flux. Plain Language Summary: The inflow of warm and saline Atlantic water into the Nordic Seas and the Arctic Ocean is crucial with respect to climate and ecology in Northern areas. In this study, we investigate the variability of this inflow on interannual timescales, using moored current and temperature measurements in the core of the inflow during 1995–2020. We show that the variability of the inflow is strongly connected to the dynamics of the Northern Atlantic. The average winter wind field toward the northeast drives a fairly stable inflow with winter‐maxima. Occasionally there is a decrease of the inflow, particularly with slowdown of winter‐maxima. These slowdowns are mainly caused by changes of the wind direction, more than the strength of the wind. We also show that the variability of the heat transport is caused by the strength of the flow, more than the water temperature. Despite the global warming trend over Northern areas with increasing air temperature and substantial ice melting both in the Arctic Ocean and over land, there is no long‐term‐trend of the Atlantic inflow over the 25‐year period 1995–2020 regarding water transport, temperature, nor heat transport. Key Points: 25 years of moored current and temperature measurements of the Atlantic inflow toward Arctic in the Norwegian Atlantic Current 1995–2020Interannual variabilities driven mainly by meridional and zonal shift of the winter wind field over the Northern AtlanticThe records show no long‐term‐trend over the 25‐year period 1995–2020, regarding volume flux, temperature, nor temperature flux [ABSTRACT FROM AUTHOR]

High-frequency eddy-covariance measurements of net ecosystem CO2 exchange (NEE) with the atmosphere are valuable resources for model parameterization, calibration, and validation. However, uncertainties in measured data, i.e., data gaps and inherent random errors, create problems for researchers attempting to quantify uncertainties in model projections of terrestrial ecosystem carbon cycling. Here, we demonstrate that a model-data fusion method (residual bootstrap) produces defensible annual NEE sums, through mimicking the behavior of random errors, filling missing values, and simulating gap-filling biases. This study estimated annual NEE sums for 53 site-years based on nine eddy-covariance tower sites in the USA, and found that our annual estimates were, in most cases, comparable in magnitude with those obtained from AmeriFlux gap-filled data. Additionally, compared to the AmeriFlux standardized gap-filling, our approach provides better NEE estimates for moderate to longer, and more frequent, data gaps. Annual accumulated uncertainties in NEE at the 95% confidence level were ±30gCm−2year−1 for evergreen needleleaf forests; ±60gCm−2year−1 for deciduous broadleaf forests; and ±80gCm−2year−1 for croplands. The residual bootstrap performed worst when gap length was greater than one month or data exclusion greater than 90% during the growing season, common to other gap-filling techniques. However, this study produced robust results for most site years when monthly data coverage during the growing season is not extremely low. We therefore suggest that the inclusion of NEE uncertainty estimates and better estimation for moderate to longer, and more frequent, data gaps as provided by the residual bootstrap approach can be beneficial for ecosystem model evaluation.

The measurement of the CO2 concentration has a wide range of applications. Traditionally, it has been used to assess air quality, with other applications linked to the experimental assessment of occupancy patterns and air renewal rates. More recently, the worldwide dissemination of COVID-19 establishing a relationship between infection risk and the mean CO2 level has abruptly led to the measurement of the CO2 concentration in order to limit the spread of this respiratory disease in the indoor environment. Therefore, the extensive application of this measurement outside of traditional air quality assessment requires an in-depth analysis of the suitability of these sensors for such modern applications. This paper discusses the performance of an array of commercial wall-mounted CO2 sensors, focusing on their application to obtain occupancy patterns and air renovation rates. This study is supported by several long-term test campaigns conducted in an in-use office building located in south-eastern Spain. The results show a spread of 19–101 ppm, with a drift of 28 ppm over 5 years, an offset of 2–301 ppm and fluctuations up to 80 ppm in instantaneous measurements not related to concentration changes. It is proposed that values averaged over 30 min, using a suitable reference value, be used to avoid erroneous results when calibration is not feasible.

Most of market-available logic analyzers are designed for hardware debug purposes and cannot record continuous measurement in long-term while in different fields of scientific research it is necessary to make data acquisition within small periods (less then 1 ms) during several hours or even days. The common example is real-time communication worst-case jitter analysis. This paper introduces an easy to implement approach how to create a logic analyzer for such kind of task on a basis of a low-cost Field-Programmable Gate Array (FPGA) kit and a personal computer. The Author provides both sample FPGA design files compatible with an open-source toolchain and the approach how to collect data using standard software and Octave scripts to post-process the experimental result. Following the Author’s guidelines even with minimal knowledge in FPGA design makes it easy to modify the introduced hardware for specific laboratory team needs.

Ammonia and greenhouse gases have a negative impact on the environment. The most important agricultural sources of ammonia are dairy cattle housing systems, which are mainly naturally ventilated. Estimating emissions for naturally ventilated barns (NVB) is challenging due to the large number of influencing factors. Most notably, the direct coupling of the inside flow regime with ambient and turbulent weather conditions causes difficulties in measuring ventilation rates, gas concentrations and emissions; thus, different methods are available. In this study, we compared the outputs of total volume flow obtained by two indirect methods (CO2 mass balance) to the direct method. The latter we assume in this study as the reference method since it is a fundamental approach that estimates airflow on the inlet. In the context of mass balancing, we compared wind related (sampling method 1) and non-wind related (sampling method 2) approaches for measuring CO2 concentrations. The total volume flow calculations were based on hourly measurements of CO2 concentrations obtained by Fourier transform infrared (FTIR) spectrometer. Data were collected over a period of six months. The values of the total volume flow were filtered for prevailing southern winds (90∘ angle). The wind related method (sampling method 1) in stable cross-inflow conditions produces more accurate and realistic values in terms of the general representation of the values in comparison with direct method and can be considered further for measurements of volume flow in the NVBs.

To overcome the lack of year-long profiling data of upper ocean layers, an autonomous Subsea Winched Profiling System (SWIPS) was developed at the German Alfred Wegener Institute (AWI), Helmholtz Center for Polar and Marine Research. Mounted on the top of a scientific mooring, the SWIPS can winch a profiling unit equipped with various sensors from 200-m water depth to the surface. The entire construction was deliberately designed to be compact and light weight in order to simplify handling and improve performance in the water. Profiler and winch units are connected by an electro-mechanical cable, which is used for a communication link between these two components. This connection enables the main control electronics to use pressure recordings from the conductivity, temperature, and depth (CTD) sensor for controlling the depth of the profiling unit in real time and a storage of the measured data in the winch unit as a safety backup. Moreover, the cable supplies the profiling unit with power from batteries stored in the winch unit. Several tests and demonstration deployments have shown the operational readiness of the system. [ABSTRACT FROM AUTHOR]

Emissions and ventilation rates (VRs) in naturally ventilated dairy barns (NVDBs) are usually measured using indirect methods, where the choice of inside and outside sampling locations (i.e. sampling strategy) is crucial. The goal of this study was to quantify the influence of the sampling strategy on the estimation of emissions and VRs. We equipped a NVDB in northern Germany with an extensive measuring setup capable of measuring emissions under all wind conditions. Ammonia (NH 3) and carbon dioxide (CO 2) concentrations were measured with two Fourier-transform infrared spectrometers. Hourly values for ventilation rates and emissions for ammonia over a period of nearly a year were derived using the CO 2 balance method and five different sampling strategies for the acquisition of indoor and outdoor concentrations were applied. When comparing the strategy estimating the highest emission level to the strategy estimating the lowest, the differences in NH 3 emissions in winter, transition, and summer season were +26%, +19% and +11%, respectively. For the ventilation rates, the differences were +80%, +94%, and 63% for the winter, transition and summer season, respectively. By accommodating inside/outside concentration measurements around the entire perimeter of the barn instead of a reduced part of the perimeter (aligned to a presumed main wind direction), the amount of available data substantially increased for around 210% for the same monitoring period. • Sampling strategy influences the estimation of NH3 and ventilation rates. • Maximum difference in sampling strategies for NH3 estimation was 26%. • Maximum difference in sampling strategies for ventilation rate estimation was 94%. • A sampling line in the middle of the barn does not provide extra information. • Measuring around the entire perimeter of the barn increased the dataset up to 210%. [ABSTRACT FROM AUTHOR]

Isoprene concentrations were measured at four heights below, within, and above the forest canopy in Wytham Woods (United Kingdom) throughout the summer of 2018 using custom‐built gas chromatographs (the iDirac). These observations were complemented with selected ancillary variables, including air temperature, photosynthetically active radiation, occasional leaf gas exchange measurements, and satellite retrievals of normalized difference vegetation and water indices. The campaign overlapped with a long and uninterrupted heatwave accompanied by moderate drought. Peak isoprene concentrations during the heatwave‐drought were up to a factor of 4 higher than those before or after. Higher temperatures during the heatwave could not account for all the observed isoprene; the enhanced abundances correlated with drought stress. Leaf‐level emissions confirmed this and also included compounds associated with ecosystem stress. This work highlights that a more in‐depth understanding of the effects of drought stress is required to better characterize isoprene emissions. Plain Language Summary: Plants emit a number of volatile organic compounds into the atmosphere as a response to environmental stimuli such as temperature and incoming sunlight. Once emitted, these compounds undergo chemical processes that can affect local air quality (for instance, contributing to the formation of pollutants such as ground‐level ozone) and climate (by contributing to the formation of aerosol particles). Numerical models have been developed to successfully simulate volatile emissions under most environmental conditions. However, one notable exception is during extreme weather events such as heatwaves and droughts, where current models appear inadequate. In this paper, we present a unique data set consisting of continuous measurements of isoprene, the main volatile emission from vegetation, during the summer of 2018 in a UK temperate forest. A prolonged heatwave and drought affected the United Kingdom that summer. We report unusually high levels of isoprene and show that higher temperatures during the heatwave cannot account for all the observed isoprene. Our analysis shows that ecosystem stress brought about by moderate drought correlates with the enhanced isoprene. This work enables an improved description of isoprene emissions under extreme events (droughts) that are predicted to become more frequent in the near future as a consequence of global change. Key Points: Isoprene concentrations were monitored for a whole growing season in a temperate forest in the United Kingdom before, during, and after the 2018 heatwaveIsoprene abundances during the heatwave increased by up to 400%, and stress‐related sesquiterpenes were observed during the heatwaveHigher temperatures in the heatwave cannot account for all the enhanced isoprene abundances, which correlate to drought stress [ABSTRACT FROM AUTHOR]

Energy demand versus energy consumption taking into account long‐term temperature measurements The comparison of the energy demand values with the energy consumption values of seven selected residential buildings shows that the determined de‐mand values are usually higher than the consumption data. This is not only put down to the reference itself, demand or consumption, but when determining the energy demand by using the approach of DIN V 18599 the results are get‐ting worse as by using DIN V 4108‐6 in conjunction with DIN V 4701‐10. Furthermore, an analysis of long‐term measurements of room and outside air temperatures at 33 locations in Germany shows that the real, time‐varying temperature curves in buildings clearly diverge from the standardised, temporally constant values according to DIN. [ABSTRACT FROM AUTHOR]

Large scale noise exposure modelling is used in epidemiological research projects as well as for noise mapping and strategic action planning. Such calculations should always be accompanied by an assessment of uncertainty, on the one hand to check for systematic deviations and on the other hand to investigate the sources of uncertainty to address them in future studies. Within the SiRENE (Short and Long Term Effects of Transportation Noise Exposure) project, a large scale nationwide assessment of Switzerland’s road, railway, and aircraft noise exposure was conducted for the year 2011. In the present follow-up study, we equipped 180 sleeping and/or living room windows with sound level meters for one week. The resulting dataset was used to validate noise exposure modelling within SiRENE. For the noise metric LDEN the comparison revealed a difference of 1.6 ± 5 dB(A) when taking all measurements into account. After removing measurement sites with noise mitigation measures not considered in the modelling, the difference to the calculation was reduced to 0.5 ± 4 dB(A). As major sources of uncertainty, the position accuracy and topicality of infrastructure and building geometries, the traffic modelling as well as the acoustic source and propagation models were identified.

Coastal seas are under increasing pressure from extreme weather events and sea level rise, resulting in impacts such as changing hydrodynamic conditions, coastal erosion, and marine heat waves. To monitor changes in coastal marine habitats, such as reefs and macrophytes meadows, which add to the resilience of our coasts, consistent, medium- to long-term seafloor observations are needed. This project aims to deliver repeated, high-frequency sonar surveys on a stationary seabed mooring of a specific target area over a period of up to several months. A new stand-alone subsea system, the Sonarlogger, based on a battery pack, low-power logger and a high-resolution scanning sonar, was developed. It allows for long-term deployments with a customisable battery pack, WI-FI download and configurable sleep state. The system has been tested for over 130 days in dynamic coastal environments off the Belgian coast. Combined with auxiliary sensors, such as for measuring currents, waves and turbidity, this system enables comprehensive studies of morphologic changes and changing benthic ecosystems. Moreover, this system has the capacity to provide measurements of coastal environments during storms, where conventional systems may fall short, providing insights into event-based changes of the seafloor., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)

In recent years, black carbon (BC) has been gaining more attention due to the diversity of anthropogenic sources and the harmful effects on human health, environment, and climate. In this paper, for the first time in Poland, the results of long-term measurements of eBC concentrations (2009–2020) at the urban background station in Zabrze (southern Poland) are presented. A Multi-Angle Absorption Photometer (MAAP) was used, which enables the measurement of eBC concentration in fine particulate matter (PM2.5). The mean concentration of eBC over the 11-year period (3.82 μg·m−3) was higher compared to the values recorded at most European urban stations. Annual averaged eBC levels showed a downward trend and clear seasonal variations, which was caused mainly by changes in the intensity of anthropogenic emissions. The impact of meteorological parameters, in particular air temperature and wind speed, which determine the intensity of emissions and the conditions of pollutant dispersion, was not without significance. The work additionally attempts to assess the possible impact of remedial actions carried out in Zabrze over the last decade. The results showed that modernization in industry and heating and maintenance of green areas potentially had the most important impact on the decline in eBC concentrations.

Tree autotrophic respiratory processes, especially stem respiration or stem CO2 efflux (E stem), are important components of the forest carbon budget. Despite efforts to investigate the controlling processes of E stem in recent years, a considerable lack in our knowledge remains on the abiotic and biotic drivers affecting E stem dynamics. It has been strongly advocated that long-term measurements would shed light onto those processes. The expensive scientific instruments needed to measure gas exchange have prevented E stem measurements from being applied on a larger temporal and spatial scale. Here, we present an automated closed dynamic chamber system based on inexpensive and industrially broadly applied CO2 sensors, reducing the costs for the sensing system to a minimum. The CO2 sensor was cross-calibrated with a commonly used gas exchange system in the laboratory and in the field, and we found very good accordance of these sensors. We tested the system under harsh tropical climatic conditions, characterized by heavy tropical rainfall events, extreme humidity and temperatures, in a moist lowland forest in Malaysia. We recorded E stem of three Dyera costulata (Miq.) trees with our prototype over various days. The variation of E stem was large among the three tree individuals and varied by 7.5-fold. However, clear diurnal changes in E stem were present in all three tree individuals. One tree showed high diurnal variation in E stem, and the relationship between E stem and temperature was characterized by a strong hysteresis. The large variations found within one single tree species highlight the importance of continuous measurement to quantify ecosystem carbon fluxes. [ABSTRACT FROM AUTHOR]

Wind resource assessments with onsite wind data are indispensable when estimating the economic feasibility of developing a large-scale commercial offshore wind farm. However, several factors of the data measured from a meteorological mast, including short observation period and instrument errors, may result in uncertainty concerning wind resource assessments. To mitigate the uncertainty of wind resource assessments at the candidate site for a large-scale commercial offshore wind farm, HeMOSU-1, the first offshore meteorological mast in Asia, has been in operation for more than 6 years since it was installed at the western coast of the Korean Peninsula in 2010. A vertical wind lidar was also installed for quantitative evaluations and calibrations of the measured data from HeMOSU-1. This study analyzed several parameters associated with the long-term wind characteristics through cross-validation between HeMOSU-1 and the wind lidar. The parameters affecting the prediction results include the shading effect from the mast, year-to-year variation, the long-term correction methods, and the period of onsite measurements. Based on this analysis, long-term wind potentials are estimated with reliable parameters. • Wind resource is analyzed using measurement data of offshore meteorological mast. • Measurement data of mast is validated and calibrated using wind lidar. • Measurement period significantly affects long-term prediction by MCP method. • Six-year measurement is sufficient to estimate the long-term wind potentials. [ABSTRACT FROM AUTHOR]

The ventilation modalities in most Chinese residences are infiltration and opening windows. We measured infiltration rates and air change rates at night, with no attempt to change occupants' behaviors, of urban residences in five climate zones of China during four seasons. Using the CO2 decay method, we found the median infiltration rate for 294 residences to be 0.34 h−1. Using occupant‐generated CO2 as tracer gas, we determined air change rates over the course of 1 year in 46 bedrooms at night from mass balance considerations. In 54% of the measurements, windows were closed, so ventilation was only by infiltration. Windows were mainly closed when the outdoor temperature was below 15°C and above 26°C. The median infiltration rates did not differ appreciably among seasons and climate zones and were always less than 0.45 h−1. [ABSTRACT FROM AUTHOR]

Turbulence characteristics in the urban boundary layer of a mid-latitude European city are investigated using a quadrant analysis of more than 12 years of eddy-covariance measurements at 39 m above street level. To describe the ongoing turbulent-exchange processes, particularly the properties of ejection and sweep events, presented here are the transfer efficiency and the similarity of momentum, heat, CO2 and H2O fluxes. In addition, an event-detection algorithm is applied to derive information on the importance of organized structures for the turbulent exchange, finding that momentum and heat fluxes are primarily controlled by atmospheric stability, whereas CO2 and H2O fluxes are more affected by the presence of active sources of the corresponding scalars (e.g. traffic for CO2 fluxes). The transfer efficiencies of momentum and heat can thus be modelled accurately, but the prediction for CO2 and H2O fluxes fails because of scalar dissimilarity. Generally, ejections are more important under buoyancy-driven unstable conditions and responsible for large structures, and sweeps are more characteristic of stable cases and smaller structures. The quadrant statistics enable the identification of scales between a hole-size factor of 10 and 20 where turbulent exchange is especially efficient and almost solely takes place by ejection–sweep cycles. This information is used to apply an event-detection algorithm, which quantifies flux fractions of such reoccurring structures to be around 0.5–0.8, with the time fraction being usually around 0.1. [ABSTRACT FROM AUTHOR]

Owing to insufficient detailed in-field observations for explaining and quantifying the wet-scavenging coefficients, especially those below-cloud (Λ below), prediction of accurate aerosol concentrations and/or behaviors in the atmosphere remains challenging. As a pioneering effort, this study focused on establishing an empirical equation for size-resolved Λ below , which represent the characteristics in Korea, using long-term aerosol number size distribution and meteorological variable measurements at two background sites in Korea (Baengnyeong and Jeju). The median Λ below values derived from the total number concentrations were 8.06 × 10−6 s−1 for Baengnyeong and 1.04 × 10−5 s−1 for Jeju, which are similar to or slightly lower than the Λ below reported by previous in-situ studies. These may be caused by differences in the precipitation rates, precipitation drop sizes, aerosol chemical/hygroscopic properties, and aerosol size distributions at the measurement sites. Although the derived parameterization can cover a wide range (10 nm to 10 μm), the derived equation for the fourth-degree polynomial shows a high correlation coefficient of 0.81, indicating that the measured and fitted Λ below converge within a narrow range. Moreover, the variation in Λ below is relatively constant for aerosol diameters larger than ∼1 μm, similar to those derived from theoretical equations rather than empirical equations in previous studies. This study is thus expected to contribute to improving the below-cloud scavenging module implemented in a chemical transport model by covering a wide range of aerosol diameters to avoid overestimation by extrapolation of Λ below. [Display omitted] • Aerosol number size distributions are measured at two background sites in Korea. • Empirical equation is developed for below-cloud scavenging coefficient (Λ below). • A lower Λ below is obtained from the newly derived equation than extant equations. • Λ below for d p > ∼1 μm shows constant variation, similar to theoretical eqs. • A wide range of aerosol diameters is covered for Λ below by avoiding extrapolation. [ABSTRACT FROM AUTHOR]

This article presents the results of experimental research on energy consumption of a prefabricated lightweight passive house located in the south of Poland. The key design parameters of the building were as follows: orientation maximizing heat gains from solar radiation, high thermal insulation of partitions, heat provided by ground source heat pump, and mechanical ventilation system with the heat exchanger. The measurements were performed in normal operating conditions in an inhabited building, throughout the years 2011–2019. For the year 2012, the article also presents the detailed structure of electricity used for particular devices. The objective of the research was to verify whether, in the long term, the building fulfils the energy consumption requirements for passive buildings. The measurements showed that energy consumption for heating was 50% lower than the value required from passive buildings. However, primary energy consumption for the entire building was exceeded already in the second year of research. This was caused by two factors: human behaviors and the type of primary energy source. The research concludes that the maintenance of passive house standard is vulnerable to human impact and difficult in the case of power source characterized by high index of expenditure on non-renewable primary energy. The article also presents recommendations on how to restore the passive house standard in the building.

The present study is based on hourly aerosol particle and ancillary data taken at three stations in Northeastern Germany 150–200 km apart in the years 2009 through 2015 in order to investigate systematic process related differences that might show up when connecting their data with forward and backward air mass trajectories. The analysis of changes in the atmospheric aerosol during air mass transport between the stations focused on two low-pollution-to-high-pollution pathways of similar distance around 200 km. Despite rather different initial size distributions the increases in total concentration of particle number, volume, and black carbon agreed within 15%. Systematic variations were found in the different concentration increases as a function of time of day at which an interstation air mass transport took place that could be explained with related source and transport processes. With Radar-based precipitation data at the stations and along connecting trajectories sub-cloud particle scavenging was investigated. At each station sub-cloud particle scavenging coefficients were determined as a function of particle size between 10 and 700 nm diameter, and as a function of precipitation sums. Median particle scavenging coefficients taken over the central part of the size range of the study strongly increased between 0.2 and 1 mm of precipitation and then planed out towards higher precipitation values. With the particle scavenging coefficients determined at the individual stations and precipitation data along connecting trajectories the sub-cloud particle scavenging analysis was extended to wet scavenging along the transport paths yielding median sub-cloud scavenging ratios over the range 0.2–25 mm of precipitation sums with a non-linear shape similar to that of the median particle scavenging coefficients at the individual stations. Whereas in light precipitation more than 80% of the initial particles in the considered range survived 150–200 km of transport, more than 50% was scavenged by more than 15 mm of precipitation during aerosol transport. [ABSTRACT FROM AUTHOR]

The results presented in this work demonstrate for the first time a distribution of elements in the spectral analysis of aerosols in the suburban continental Balkan Peninsula. Samples were collected in the suburban area of Belgrade (Serbia) in the period from March 2012 till December 2013. Results presented here are from long-term measurements of masses of size-segregated aerosols and macro- and microelements in the range of PM0.27-16. The following elements were analyzed: Al, Ag, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sb, Ti, Tl, V, and Zn; levels of Be, Hg, and Se were under the detection limits in all samples. Average concentrations and time and seasonal variations of particulate matter (PM) as well as element contents and their percentage shares are given. The results showed the domination of particle content around the accumulation mode in the range of 0.53 < Dp < 1.06 μm, but the fractional distribution of elements showed maximal average concentrations in different fractions depending on the origin of each element. Crustal elements (Al, Ca, Fe, Mg, Mn, Ti, etc.) dominated in coarse mode, while anthropogenic elements (As, Cd, Cu, Pb, Sb, etc.) were mainly distributed in fine mode fractions. Some elements, such are As and Ni, were detected in investigated aerosols only occasionally, while others, such as Ca, Fe, and Mg, were detected in all analyzed samples. The application of multivariate analysis (PCA) demonstrated the connection between the elements of similar origin, in fine fractions mainly of anthropogenic origin, while in coarse mode of crustal origin, indicating the resuspension with contribution of about 40%. The contents of some measured elements were compared with their contents in aerosols in some European suburban areas. [ABSTRACT FROM AUTHOR]

We have found distinct long-period changes in erythemal UV radiation (Qer) characterized by a pronounced decrease at the end of the 1970s and a statistically significant positive trend of more than 5%/10 years since 1979 over the territory of the Moscow region according to the measurements and reconstruction model. The positive Qer trend is shown to be associated mainly with a decrease in the effective cloud amount and total ozone content (TOC). Due to these variations, UV resources have significantly changed in spring for the population with the most vulnerable skin type I, which means a transition from the UV optimum to UV moderate excess conditions. The simulation experiments using the INM-RSHU chemistry climate model (CCM) for several scenarios with and without anthropogenic factors have revealed that the variations in the anthropogenic emissions of halogens have the most significant impact on the variability of TOC and Qer. Among natural factors, noticeable effects are observed due to volcanic aerosol. The calculations of the cloud transmittance of Qer are generally consistent with the measurements; however, they do not reproduce the observed value of the positive trend. [ABSTRACT FROM AUTHOR]

Elemental carbon (EC) and organic carbon (OC) are major components of atmospheric PM 2.5. In this article we represent the results of long-term measurements (8–12 years) of EC and OC at three different background sites in Finland: in a rural area (Virolahti) since the summer 2010, in a marine environment (Utö) since the summer 2011, and in a clean arctic environment (Pallas/Matorova) since 2014. The concentrations of OC and EC were measured with a semi-continuous organic and elemental carbon analyser (SC-OCEC) in all the sites. The yearly average concentrations of OC varied between 0.96–3.1, 0.76–1.6 and 0.30–0.69 μg m−3 at the rural (Virolahti), marine (Utö) and arctic (Pallas/Matorova) sites, respectively. Similarly, the corresponding yearly average concentrations of EC ranged between 0.095–0.48, 0.090–0.2 and 0.010–0.086 μg m−3 at those sites. A clear seasonal variation in OC and EC concentrations was observed at each measurement site. OC concentrations were highest during summertime whereas EC concentrations were highest in wintertime. The seasonality of OC was clearest at the Arctic site that had also the largest temperature variation and shortest growing season resulting in a sharp increase in OC concentrations from June to August. At all the measurement sites, OC concentrations gradually increased when the temperature rose over sub-zero temperatures whereas the daily average EC concentrations did not show as apparent temperature dependence as OC. Based on the cluster analysis, highest OC and EC concentrations, and the highest total load for EC (23–32%), at all the sites were detected with the air mass origin of southeast. In the marine environment, the effect of black carbon from ship plumes was investigated. The limit for ship fuel sulfur content changed during the measurement period (in January 2015), but it was not observed to influence the Optical EC concentrations. Overall, long-term, continuous measurements are crucial when the time trends in air quality and the effect of emission mitigation actions are investigated. In this study, a slight decrease in OC was observed at the Marine site, however, a decrease for EC was seen both at the rural and marine sites suggesting that the emission mitigation actions like EURO limits for light vehicles or improved after-treatment systems developed for industry and energy production have already decreased the background concentrations in rural areas. • Long-term EC and OC measurements were conducted in three contrasting background areas. • Biogenic sources affected clearly OC concentrations in the summertime. • EC had a significant decreasing trend at the rural site. • Sulfur content in ship fuels was not influencing Optical EC concentration at the marine site. [ABSTRACT FROM AUTHOR]

When designing energy efficient buildings it is useful to study existing climate—responsive building typologies. The wind towers or wind-catchers of Yazd city in Iran are typical examples of such a typology. Although many previous studies have investigated the performance of various types of wind catcher systems, studies based on a long-term real-life measurement can be rarely found. In this study a long-term whole year monitoring campaign on an existing full scale four sided wind catcher in Yazd was carried out in 2014–2015. Three prevailing wind directions were identified and the measured on-site wind speeds were used to estimate the wind induced natural ventilation potential of the tower. A shaft/tower airflow performance index was developed. The monitoring results were compared to the ASHRAE Standard 62:2001 ventilation rate requirement. Results show that the total ventilation rate of the wind tower surpasses the ASHRAE Standard requirements. Furthermore it shows that the shafts are exposed to the prevailing wind directions perform better. For more effective natural ventilation a wind tower with adaptable openings/shafts are proposed. [ABSTRACT FROM AUTHOR]

• 8-years of continuous CO 2 fluxes from a pristine East-Central European peatland. • A temperate peatland with an overall robust sink of CO 2. • CO 2 source under dry and hot conditions. • High summertime TA and VPD limiting net ecosystem production. • Net ecosystem production increases during warmer spring and decreases in a hot summer. Peatlands are among the largest stocks of soil carbon, which can be stored for thousands of years under well-wetted conditions. The main goals of the study were to assess annual and seasonal CO 2 balances of a temperate peatland and the main biophysical factors affecting these CO 2 fluxes. The studied peatland was usually a CO 2 sink with a mean annual net ecosystem production (NEP) of 110±83 gCO 2 -C·m−2·yr−1 and extreme balances in 2006 (-17 gCO 2 -C·m−2·yr−1) and 2011 (194 gCO 2 -C·m−2·yr−1). Annual fluxes were not significantly correlated with biophysical variables, unlike seasonal data. Furthermore, the average air temperature in spring and summer was related to NEP at r2=0.65 and r2=0.61, respectively (warmer spring increased NEP while hot summer decreased NEP in these seasons). A decrease in daytime measured NEP during the summer period (June-August) was observed when TA exceeded 25 °C or VPD was above 15 hPa, respectively, due to the growing R eco and possibly plant photorespiration. These findings suggest a negative impact of ongoing global warming on temperate peatland CO 2 balances. [ABSTRACT FROM AUTHOR]

Shallow and deep branches of the Meridional Overturning Circulation pass through the Rockall Trough and Iceland Basin where measurements of salinity and temperature have been made for 65 years. There is a very small number of decadal-scale time series in the world ocean, so this long-term data collection represents an unusually rich resource for climate science. The early data sets of surface temperature and salinity collected by ocean weather ships provided a previously unseen picture of the annual cycle of these properties as well as multiyear variability. In 1975, regular, repeated sampling of the full-depth deep ocean began to reveal the variability of water masses and details of their circulation. Here, we describe the history of sampling in the region and the main scientific discoveries about ocean circulation and variability made using these data. Continuing sustained observing of temperature, salinity, nutrients, and carbon from ships will contribute to the international focus in the subpolar gyre over the next decade.

Recent studies have shown that (three-electrode) electrochemical sensors can be utilised for air quality monitoring and exposure assessment. The long-term performance of these sensors is however, often limited by the effects of ambient meteorological parameters on the sensor baseline, in particular temperature. If electrochemical (EC) sensors are to be adopted for air quality measurement over extended periods (months), this effect must be accounted for. Recent long-term, ambient measurements of CO, NO and NO 2 using EC sensors have revealed that temperature (and relative humidity (RH)) had an effect on the baseline which was more pronounced in the case of NO sensors with coefficient of determination, R 2 of 0.9 when compared to CO and NO 2 with R 2 < 0.2. In this paper we present a correction methodology that quantifies this effect (referred to here as fitted baseline), implementing these correction on the EC measurements. We found that EC sensors corrected for baseline-temperature effect using the method describe in this paper show good agreement when compared with traditional reference instrument. The coefficient of determination R 2 of 0.7–0.8 and gradient of 0.9 was observed for baseline-temperature corrected NO compared to R 2 = 0.02 prior to baseline-temperature correction. Furthermore, the correction methodology was validated by comparing the temperature-baseline with proxy temperature compensating measurements obtained from the fourth electrode of a set of novel four-electrode electrochemical sensors. A good agreement (R 2 = 0.9, with gradients = 0.7–1.08 for NO and 0.5 < R 2 < 0.73 for CO) was observed between temperature fitted baselines and outputs from the fourth electrodes (also known non-sensing/auxiliary electrode). Meanwhile, the long-term stability (calibrated signal output) of temperature-corrected data was evaluated by comparing the change in sensor gain to meteorological parameters including temperature, relative humidity, wind speed and wind direction. The results showed that there was no statistically significant change in sensitivity (two-sided t -test, p = 0.34) of the temperature-corrected electrochemical sensor with respect to these parameters (over several months). This work demonstrates that using the baseline-temperature correction methodology described in this paper, electrochemical sensors can be used for long-term (months), quantitative measurements of air quality gases at the parts per billion volume (ppb) mixing ratio level typical of ambient conditions in the urban environment. [ABSTRACT FROM AUTHOR]

This study presents the long-term measurements of traffic load induced settlement of pavement surface in Saga airport highway, Japan. In addition, the subground characteristics of the deposit were discussed in associated with their typical properties such as; high sensitivity, high compressibility, and low bearing capacity. The basic features of deposit are characterized to be soft alluvial deposit with thickness 20 - 25 m with natural water contents are much higher than their corresponding liquid limits. Permeability of the salty clay layer is approximated 3 to 5 times of the Ariake clay permeability. The settlement profiles along the Saga airport highway visualized a non uniform differential settlement. Large differential settlement occurred in between the two box culverts supported by end bearing piles. A dynamic impact is considered as one factor affecting the large observed settlement in the central part of the road section between the two box culverts. The observed total settlement was around 0.5 m after 3 years open for traffic; it was mainly accumulated due to consolidation settlement of embankment highway. It can be justified that the settlement induced by traffic loading is approximately around 20% of the total settlement.