Atmospheric sciences

Reliable and self-consistent data on air quality are needed for an extensive period of time for conducting longterm, or even lifetime health impact assessments. We have modelled the urban-scale concentrations of fine particulate matter (PM 2.5 ) in the Helsinki Metropolitan Area for a period of 35 years, from 1980 to 2014. The regional background concentrations were evaluated based on reanalyses of the atmospheric composition on global and European scales, using the SILAM model. The high-resolution urban computations included both the emissions originated from vehicular traffic (separately exhaust and suspension emissions) and those from small-scale combustion, and were conducted using the road network dispersion model CAR-FMI and the multiplesource Gaussian dispersion model UDM-FMI. The modelled concentrations of PM 2.5 agreed fairly well with the measured data at a regional background station and at four urban measurement stations, during 1999-2014. The modelled concentration trends were also evaluated for earlier years, until 1988, using proxy analyses. There was no systematic deterioration of the agreement of predictions and data for earlier years (the 1980s and 1990s), compared with the results for more recent years (2000s and early 2010s). The local vehicular emissions were about 5 times higher in the 1980s, compared with the emissions during the latest considered years. The local small-scale combustion emissions increased slightly over time. The highest urban concentrations of PM 2.5 occurred in the 1980s; these have since decreased to about to a half of the highest values. In general, regional background was the largest contribution in this area. Vehicular exhaust has been the most important local source, but the relative shares of both small-scale combustion and vehicular non-exhaust emissions have increased in time. The study has provided long-term, high-resolution concentration databases on regional and urban scales that can be used for the assessment of health effects associated with air pollution.

Long term Atlantic tropical storm activity is described by the time series of the yearly Accumulated Cyclone Energy (ACE) Index for the time interval 1851-2007. ACE is a measure of total wind energy for North Atlantic basin and land falling tropical cyclone activity. Since the ACE index reflects a combination of storm intensity and duration it is a better measure of overall activity and likely damage than the number of either basin or land falling tropical storms or hurricanes. The yearly ACE time series is non-stationary, and one step toward detecting possible long-term quasi-periods is to detrend the original data. In this paper, we use a procedure for data transformation by which ACE index is fitted in least square sense with polynomials of increasing order, followed by detrend. It is shown that, with some approximation, the obtained time series is cyclostationary, and a multi-decadal oscillation is detectable, as indicated by the power spectrum analysis.

The tropopause is the boundary between the troposphere and the stratosphere, so its height determines the nature of processes in the atmosphere and depends on them. The criterion for determining the height of the tropopause is a decrease in the vertical temperature gradient in a layer above 5 km and at least 2 km thick. Consequently, the uncertainty in determining the height of the section between the troposphere and the stratosphere is 2 km or more. In addition, the temperature profile changes due to the influence of many reasons, so sometimes the height of the tropopause cannot even be determined. The optical properties of air in the troposphere and stratosphere differ, which makes it possible to measure the height of the section with high accuracy using a radiosonde with an optical sensor. The launches of radiosondes with optical sensors made it possible to measure the height of the tropopause by changing the attenuation coefficient of visible light. It turned out that the lower edge of the tropopause corresponds to a sharp change in the attenuation coefficient. The repeatability of the results was confirmed by the simultaneous launch of radiosondes. The results of the work will be useful for the tasks of weather forecasting and climate research.

The development of Jakarta as a metropolitan city worsens the PM 2.5 concentration in the area, causes health problems for the citizens, and becomes a major public concern. In this study, we use Pearson correlation and convergent cross mapping (CCM) to analyze any correlation between air quality and individual meteorological parameters, as well as the local PM2.5 nonlinear coupling pattern at two different locations in Jakarta. The influence of meteorological parameters and other pollutants in various seasons can be used to determine the variability of PM2.5. We found that the PM2.5 concentration is affected by PM10, SO2, and NO2 pollutant and is negatively correlated with precipitation, relative humidity, and the wind speed in all variations of the season. Causality analysis using CCM showed that PM2.5 coupling patterns differ for every season. The highest causality values (ρ) for air quality parameters are 0.74 (PM 10), 0.68 (SO2), 0.52 (wind speed), and 0.51 (temperature). In Central Jakarta and South Jakarta, the coupling pattern of PM2.5 concentration and air quality parameters increased during the DJF (December-February) season, while the coupling pattern of PM2.5 concentration and meteorological parameters increased during the DJF and MAM (March-May) seasons. During the JJA (June-August) season, most of the meteorological parameters did not have any impact, whereas the increased humidity during the SON (September-November) season also increased the PM2.5 concentration. In conclusion, the significant outcome of our research is to show that individual air quality and meteorological parameters had an influence on local PM2.5 concentrations in the Jakarta region. In addition, it has been proved that CCM can analyze mirage correlation better than other correlation methods.

High seismicity rates in and around West Java and Sumatra occur as a result of the Indo-Australian plate converging with and subducting beneath the Sunda plate. Large megathrust events associated with this process likely pose a major earthquake and tsunami hazard to the surrounding community, but further effort is required to help understand both the likelihood and frequency of such events. With this in mind, we exploit catalog seismic data sourced from the Agency for Meteorology, Climatology, and Geophysics (BMKG) of Indonesia and the International Seismological Centre (ISC) for the period April 2009 through to July 2020, in order to conduct earthquake hypocenter relocation using a teleseismic double-difference method. Our results reveal a large seismic gap to the south of West Java and southeast Sumatra, which is in agreement with a previous GPS study that finds the region to be a potential future source of megathrust earthquakes. To investigate this further, tsunami modeling was ...

CO mixing ratios in air have been measured continuously at Cape Point (34'21's; 18O29'E) between 1978 and 1981. The results show a seasonal variation of the CO mixing ratios with minimum values of 53 p.p.b.v. during January/February and maximum values of 87 p.p.b.v. during September/October. Short-term variations of CO mixing ratios in clean, undisturbed air were lacking, indicating that CO is well mixed in the Southern Hemisphere at latitudes of 20-40" S and that the observed seasonal variation is not due to temporal changes of local and regional source strengths. The seasonality of CO is explained by the seasonal variation of OH and by the north-south shift of the intertropical convergence zone. The agreement of CO mixing ratios measured at Cape Point and over the Southern Atlantic in 1971/1972 indicates that the southern hemispheric CO mixing ratios cannot have changed by more than 5-1096 during the last decade. Tellus 36B (1984), 4

Carbon sequestrated in marine ecosystems has been termed “blue carbon”, and seagrass meadows are one of the most dominant blue carbon stocks. Globally, one of the major distribution sites of seagrass meadows is coral reef flat. Recent studies have revealed that the amount of sedimentary organic matter in tropical and subtropical coasts is comparable to that in temperate coasts. However, these estimations are based on a few data and have wide range. Since quantifying organic carbon in the carbonate sediment is technically difficult and costly, easier methods for estimating the amount of organic carbon in seagrass meadows are strongly needed to assess the global blue carbon stocks for mitigation of global warming. Seagrass biomass is suggested to have responsible for the variability of seagrass carbon sink capacity, but the models have not been presented yet. To identify the relationship between seagrass biomass and blue carbon stocks, we developed a new box corer which can facilitate...

A physics-based cloud identification scheme, originally developed for a machine-learning forecast system, was applied to verify cloud location and coverage bias errors from two years of 6-h forecasts. The routine identifies stable and unstable environments by assessing the potential for buoyant versus stable cloud formation. The efficacy of the scheme is documented by investigating its ability to identify cloud patterns and systematic forecast errors. Results showed that stable cloud forecasts contained widespread, persistent negative cloud cover biases most likely associated with turbulent, radiative, and microphysical feedback processes. In contrast, unstable clouds were better predicted despite being poorly resolved. This suggests that scale aliasing, while energetically problematic, results in less-severe short-term cloud cover errors. This study also evaluated Geostationary Operational Environmental Satellite (GOES) cloud-base retrievals for their effectiveness at identifying r...

During the solar eclipse of 11 August 1999, measurements of sap flow at branch and stem level were made in a 75-year-old beech tree which was 27 m high growing near Ghent, Belgium. The sky was relatively free from clouds during the eclipse which reached its maximum at 10.26 h GMT (=10.36 h True Solar Time). Measurements also included short-wave radiation, air temperature and vapour pressure deficit. The daily variation of the sap flows and of short-wave radiation and vapour pressure deficit were compared to a reference based on mean diurnal cycles. During the eclipse short-wave radiation, air temperature and vapour pressure deficit showed a maximum reduction between the pre-eclipse maximum and the following minimum of respectively 439 W/m 2 , 3.0 • C and 0.27 kPa. The reduction of the solar energy resulted in the formation of a temporary temperature inversion above the canopy. At the time of maximum eclipse the sap flow rates at branch level and at stem level were reduced by 92 and 76%, respectively, indicating non-stationary flow conditions in the beech tree. Due to the eclipse, the tree reduced its water loss from transpiration by 32.0 kg of water, being about 25% of the total amount which is transpired by the beech tree during a sunny day in August. Regression analysis indicated that both short-wave radiation and vapour pressure deficit changed in a nearly linear fashion during the eclipse. Sap flow rates were given by an exponential equation, allowing the description of sap flow dynamics in terms of time lag and rate of change.

Urban green spaces function as biological filters in reducing atmospheric particles. Yet there is a profound requisite to identify the most effective plant species by their leaf traits that can enhance particle capture and improve ambient air quality. In this study, we investigated leaves of 96 perennial urban plant species consisting of 43 deciduous broadleaf trees, 32 deciduous broadleaf shrubs, 14 deciduous and evergreen needle/scale-like, 5 evergreen broadleaves, and 2 climber species for their differences in net particle accumulation. Leaf saturation isothermal remanent magnetization (SIRM), a proxy for traffic and industry induced particle accumulation, along with morphological and anatomical leaf traits were analyzed in a common garden experiment in June and September 2016. Leaf SIRM varied significantly between plant species. The most effective net particle accumulating plant species with a median value of 23.0 µA were Buddleja davidii, Viburnum opulus, Carpinus betulus, Quercus ilex, Viburnum lantana, Rosa rugosa, Sorbus aria, Aesculus hippocastanum, Pseudotsuga menziesii, Acer campestre. The least effective net particle accumulating plant species with a median value of 10.4 µA were Populus alba, Alnus glutinosa, Larix kaempferi, Larix decidua, Plantanus x acerilifolia, Acer pseudoplatanus, Robinia pseudoacacia, Quercus palustris, Rosa canina, Liquidambar styraciflua. The "variable importance" in net particle accumulation for the investigated plant species was achieved using ®randomForest. The presence of leaf trichomes and specific leaf area were identified as important leaf traits for categorization of the selected plant species in low, medium, and high net particle accumulators. The extensive analysis of plant species at leaf-level with distinct micro-morphology contributes to a better understanding of plant species behavior in net particle capture and their contribution in reducing atmospheric particulate matter. Furthermore, this study has practical implications for policymakers in making informed choices when planning urban green infrastructures. Lastly, our study can become a basis to validate atmospheric deposition model using species-specific information.

Landslides are one of the many catastrophic events which result in massive destruction and loss of lives across the globe. Hence, an appropriate forecasting technique is essential in order to predict such potential weak slip planes which may eventually lead to landslides. Here, we present a study where Fracture Induced Electromagnetic Radiation (FEMR) technique has been used to identify such regions of potential "activity" in a study area around IISER Bhopal Hill, India, stretched along a length of approximately 1 km. The hill is majorly composed of basaltic rocks belonging to the Deccan traps which have been heavily weathered and have resulted in the formation of unconsolidated soil cover. In numerous locations, it has been observed that natural gullies have formed as a result of the breakage of masses from weak slip planes. In this study, we have taken linear measurements along four different profiles along and across the hill using a portable measuring device ANGEL-M. Anomalously high amplitudes of FEMR values are obtained in the regions which consist of weak slip planes which can be considered to be potential zones of future landslides. The results were further verified by calculating the factor of safety for a few locations along the profiles where anomalies in the FEMR data were compared. Consequently, predicting areas prone to natural calamities such as landslides has always been a priority in terms of current research. Hence, we have made an active endeavor to propose a new technique in order to identify landslide-prone areas by detecting the adjoining weak slip planes.

The hot electron transport properties of the Cu/Si(001) interface have been studied using ballistic electron emission microscopy (BEEM). The Schottky barrier height was measured to be 0.64±0.02 eV. The scanning tunneling microscopy images provide evidence of Volmer–Weber growth of the metal, while Rutherford backscattering spectrometry data corroborated with Auger depth profiling indicate distinct Cu and Si regions with little intermixing. Comparison with Au/Si(001) BEEM data provides some insight into the hot electron transport and scattering properties of the Cu/Si(001) interface.

Uncertainty requirements for climate observations are more stringent than for weather observations because of the scale dependency of natural variation. At present there is no space-based climate observing system, so weather observations have to be aggregated for the study of large-scale change. The management and minimization of uncertainty sources in weather observations are, therefore, a high priority. This work is a first attempt at investigating if a single long-term record can be assembled with temperature retrievals from three hyperspectral satellite sounders in polar orbit: the Atmospheric Infrared Sounder (AIRS) on Aqua in afternoon orbit since 2002, the Infrared Atmospheric Sounding Interferometer (IASI) on MetOp-A in morning orbit since 2006, and the Cross-track Infrared Sounder (CrIS) on board the Suomi National Polar-Orbiting Partnership in afternoon orbit since 2011. These instruments measure not only the vertical atmospheric structure but also atmospheric composition,...

Line-by-line calculations of up-welling atmospheric radiances are compared to clear-sky radiances observed with the University of Wisconsin High-resolution Interferometer Sounder (HIS). We concentrate on water emission in the 1400-1750 cm-' region which is sensitive to the Nz-broadened water continuum. This work applies our recently developed water continuum derived from new laboratory data to atmospheric emission measurements. The atmospheric state under clear-sky conditions was characterized with radiosonde and LIDAR observations. Radiances in-between absorption lines probe the lower troposphere, where the water vapor profiles are best characterized, allowing comparison of several different water continuum models. Closer to the centers of the absorption lines all models yield relatively large errors, most likely due to inaccuracies in the high altitude water vapor radiosonde measurements.

Tropospheric carbon monoxide (CO) column densities were retrieved from 491 nadir infrared spectra obtained by the University of Wisconsin's High‐Resolution Interferometer Sounder (HIS) during a cross‐country flight of a NASA ER‐2 on September 12–13, 1993 (UT). A classical, Fourier‐based signal‐processing technique was utilized to retrieve the CO column density from the 2135–2200 cm−1 portion of the CO 1–0 vibration‐rotation band. Error analysis indicates column CO retrieval uncertainties of approximately ±10%. Retrieved CO column densities over the western United States from this flight, ∼1.2×1018 cm−2, agree well with previous ground‐based CO column measurements over the western United States at the same season. Derived CO sensitivity functions for these measurements possess a broad peak centered in the 500–600 mbar region, thus implying the retrieved tropospheric CO mixing ratios are indicative of the mean free troposphere (mft). Across the United States, three spatial groupin...

The Department of Energy Atmospheric Radiation Measurement Program (ARM) has funded the development and installation of five ground-based atmospheric emitted radiance interferometer (AERI) systems at the Southern Great Plains (SGP) site. The purpose of this paper is to provide an overview of the AERI instrument, improvement of the AERI temperature and moisture retrieval technique, new profiling utility, and validation of high-temporal-resolution AERI-derived stability indices important for convective nowcasting. AERI systems have been built at the University of Wisconsin-Madison, Madison, Wisconsin, and deployed in the Oklahoma-Kansas area collocated with National Oceanic and Atmospheric Administration 404-MHz wind profilers at Lamont, Vici, Purcell, and Morris, Oklahoma, and Hillsboro, Kansas. The AERI systems produce absolutely calibrated atmospheric infrared emitted radiances at one-wavenumber resolution from 3 to 20 m at less than 10-min temporal resolution. The instruments are robust, are automated in the field, and are monitored via the Internet in near-real time. The infrared radiances measured by the AERI systems contain meteorological information about the vertical structure of temperature and water vapor in the planetary boundary layer (PBL; 0-3 km). A mature temperature and water vapor retrieval algorithm has been developed over a 10-yr period that provides vertical profiles at less than 10-min temporal resolution to 3 km in the PBL. A statistical retrieval is combined with the hourly Geostationary Operational Environmental Satellite (GOES) sounder water vapor or Rapid Update Cycle, version 2, numerical weather prediction (NWP) model profiles to provide a nominal hybrid first guess of temperature and moisture to the AERI physical retrieval algorithm. The hourly satellite or NWP data provide a best estimate of the atmospheric state in the upper PBL; the AERI radiances provide the mesoscale temperature and moisture profile correction in the PBL to the large-scale GOES and NWP model profiles at high temporal resolution. The retrieval product has been named AERIplus because the first guess used for the mathematical physical inversion uses an optimal combination of statistical climatological, satellite, and numerical model data to provide a best estimate of the atmospheric state. The AERI physical retrieval algorithm adjusts the boundary layer temperature and moisture structure provided by the hybrid first guess to fit the observed AERI downwelling radiance measurement. This provides a calculated AERI temperature and moisture profile using AERIobserved radiances ''plus'' the best-known atmospheric state above the boundary layer using NWP or satellite data. AERIplus retrieval accuracy for temperature has been determined to be better than 1 K, and water vapor retrieval accuracy is approximately 5% in absolute water vapor when compared with well-calibrated radiosondes from the surface to an altitude of 3 km. Because AERI can monitor the thermodynamics where the atmosphere usually changes most rapidly, atmospheric stability tendency information is readily available from the system. High-temporal-resolution retrieval of convective available potential energy, convective inhibition, and PBL equivalent potential temperature e are provided in near-real time from all five AERI systems at the ARM SGP site, offering a unique look at the atmospheric state. This new source of meteorological data has shown excellent skill in detecting rapid synoptic and mesoscale meteorological changes within clear atmospheric conditions. This method has utility in nowcasting temperature inversion strength and destabilization caused by e advection. This high-temporal-resolution monitoring of rapid atmospheric destabilization is especially important for nowcasting severe convection.

Nadir looking infrared spectra of a forest fire smoke plume off the south shore of Long Island, New York, were obtained from a NASA ER-2 aircraft during two spatially coincident over-flights on the morning of August 25, 1995. These spectra exhibit enhanced CO column densities at the same geographic locations over the smoke plume on both over-flights with a peak CO column density ∼ 2.6 × 10 18 cm -2 , ∼ 6σ above the clear air background. Meteorological conditions suggest the smoke plume was confined to the planetary boundary layer (PBL), pressures ≥ 850 mb, and perhaps to a thin region near the top of the PBL. Constraining the excess CO to the PBL yields a CO mixing ratio ∼ 1,400 ppbv. Further constraining the CO to the model layer nearest the top of the PBL, 852-878 mb, yields ∼ 4,300 ppbv. From the spatial overlap of the spectra, the estimated width of the CO rich portion of the plume is ≤ 2.8 km vs. a plume width of ∼ 5 km in GOES-8 satellite visible images.

The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5–50 μm), the spectrum of solar radiation reflected by the Earth and its atmosphere (320–2300 nm), and radio occu...

Infrared ultra-spectral spectrometers have brought in a new era in satellite remote atmospheric sounding capability. During the 1970s, after the implementation of the first satellite sounding instruments, it became evident that much higher vertical resolution sounding information was needed to be able to forecast life and property threatening localized severe weather. The demonstration of the ultra-spectral radiance measurement technology required to achieve higher vertical resolution began in 1985, with the aircraft flights of the High resolution Interferometer Sounder (HIS) instrument. The development of satellite instruments designed to have a HIS-like measurement capability was initiated in the late 1980's. Today, after more than a decade of development time, the Atmospheric Infrared Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI) are now operating successfully from the Aqua and MetOp polar orbiting satellites. The successful development and ground demonstration of the Geostationary Imaging Fourier Transform Spectrometer (GIFTS), during this decade, is now paving the way toward the implementation of the ultraspectral sounding capability on the international system of geostationary environmental satellites. This note reviews the evolution of the satellite ultra-spectral sounding systems, shows examples of current polar satellite sounding capability, and discusses future advances planned for geostationary orbit.

The influence of the anisotropy of the (5×n) reconstructed (100) face of gold on the generation of vacancy islands by sputtering with 600 eV Ar+ ions has been investigated by scanning tunneling microscopy. The shapes of these islands, bounded by monoatomic steps, are shown to be growth shapes, rather than equilibrium shapes. The growth mechanisms leading to these shapes are discussed.

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) is a satellite mission implemented by the European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), to measure global profiles of aerosols, clouds and precipitation properties together with radiative fluxes and derived heating rates. The simultaneous measurements of the vertical structure and horizontal distribution of cloud and aerosol fields, together with outgoing radiation, will be used in particular to evaluate their representation in weather forecasting and climate models and to improve our understanding of cloud and aerosol radiative impact and feedback mechanisms. To achieve the objective, the goal is that a retrieved scene with footprint size of 10 km × 10 km is measured with sufficiently high resolution that the atmospheric vertical profile of short-wave (solar) and long-wave (thermal) flux can be reconstructed with an accuracy of 10 W m -2 at the top of the atmosphere. To optimise the performance of the two active instruments, the platform will fly at a relatively low altitude of 393 km, with an equatorial revisit time of 25 d. The scientific payload consists of four instruments: an atmospheric lidar, a cloudprofiling radar with Doppler capability, a multi-spectral imager and a broadband radiometer. Co-located measurements from these instruments are processed in the ground segment, which produces and distributes a wide range of science data products. As well as the Level 1 (L1) product of each instrument, a large number of multiple-instrument L2 products have been developed, in both Europe and Japan, benefiting from the data synergy. An end-to-end simulator and several test scenes have been developed that simulate EarthCARE observations and provide a development and test environment for L1 and L2 processors. Within this paper the EarthCARE observational requirements are addressed. An overview is given of the space segment with a detailed description of the four science instruments, demonstrating how the observational requirements will be met. Furthermore, the elements of the space segment and ground segment that are relevant for science data users are described and the data products are introduced.

The Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) is a satellite mission implemented by the European Space Agency (ESA), in cooperation with the Japan Aerospace Exploration Agency (JAXA), to measure global profiles of aerosols, clouds and precipitation properties together with radiative fluxes and derived heating rates. The simultaneous measurements of the vertical structure and horizontal distribution of cloud and aerosol fields, together with outgoing radiation, will be used in particular to evaluate their representation in weather forecasting and climate models and to improve our understanding of cloud and aerosol radiative impact and feedback mechanisms. To achieve the objective, the goal is that a retrieved scene with footprint size of 10 km × 10 km is measured with sufficiently high resolution that the atmospheric vertical profile of short-wave (solar) and long-wave (thermal) flux can be reconstructed with an accuracy of 10 W m -2 at the top of the atmosphere. To optimise the performance of the two active instruments, the platform will fly at a relatively low altitude of 393 km, with an equatorial revisit time of 25 d. The scientific payload consists of four instruments: an atmospheric lidar, a cloudprofiling radar with Doppler capability, a multi-spectral imager and a broadband radiometer. Co-located measurements from these instruments are processed in the ground segment, which produces and distributes a wide range of science data products. As well as the Level 1 (L1) product of each instrument, a large number of multiple-instrument L2 products have been developed, in both Europe and Japan, benefiting from the data synergy. An end-to-end simulator and several test scenes have been developed that simulate EarthCARE observations and provide a development and test environment for L1 and L2 processors. Within this paper the EarthCARE observational requirements are addressed. An overview is given of the space segment with a detailed description of the four science instruments, demonstrating how the observational requirements will be met. Furthermore, the elements of the space segment and ground segment that are relevant for science data users are described and the data products are introduced.

We present biogenic VOC, including sesquiterpenes, measurements at the SMEAR II station (Station For Measuring Forest Ecosystem-Atmosphere Relations) in Finland using an in situ gas chromatograph mass-spectrometer with 2 h time resolution. The measurements were conducted over the period October 2010-October 2011, at least one week every month. To our knowledge there are no earlier species-speciated semi-continuous BVOC data also covering dormant periods. This was also the first time sesquiterpene mixing ratios were measured in a boreal forest. During the winter months, and still in March, the mixing ratios of all biogenic compounds were very low, most of the time below detection limits. The monoterpene mixing ratios increased in April and started to show diurnal variability, with maximum mixing ratio at night and minima during the day. The diurnal variability continued until October, after which the mixing ratios decreased and then only occasional episodes took place. The diurnal variation was affected by boundary layer height. Sesquiterpene mixing ratios were very low, only a few ppt. The main sesquiterpenes were longifolene and isolongifolene. The diurnal variation of isoprene was opposite to the mono-and sesquiterpene diurnal curve due to isoprene's light dependent emissions. Due to its daytime maximum mixing ratios, isoprene also dominated hydroxyl radical reactivity in summer even though our isoprene measurements are underestimates due to a breakthrough in a cold trap.

The characteristics of ground deformation induced by the excavation of underground orebodies are summarized based on an analysis of over 10 years of deformation data recorded in the eastern mining area of the Chengchao mine in China. These data are combined with laws governing the development of ground-surface cracking and collapse to study the corresponding failure mechanism. The results indicate that the ground deformation in most mining-affected areas increases at a low rate of acceleration. Furthermore, the displacement-time curves are exponential in nature (that is, the relationship between displacement and time can be expressed using an exponent). Curves representing the ratio of the horizontal: vertical displacement over time show different behaviors including convergence, fluctuation, increase, fall-back, exponential, and linear trends. The originally designed scope of the ground movement is significantly smaller than the scope of the actual ground movement suggested by the in situ deformation data (the difference in movement angle amounts to 18°; the difference in break angle to 20°). After rapidly decreasing in the initial mining stage, the break angle remained constant (~ 50°) for a long period of time. The surrounding rock mass conformed to a failure model in which the rock mass topples toward the mined-out area leading to failure surfaces being formed in the deep parts of the rock mass. The inclination angles of these failure surfaces are different in different excavation-affected areas. The excavation-affected area in which the failure surfaces occur can be viewed as a large-scale surface-cracking zone. Outside this zone, small-scale surface cracking can be observed and this area can be viewed as a small-scale surface-cracking zone. In the area investigated, the occurrence of ground movement that is significantly larger than predicted is attributed to the combined effect of engineering-geological conditions, hydrogeological conditions, and the burial depth and geometric configuration of the underground orebodies of the mine. More specifically, the surrounding rock mass is continuously subjected to large-scale unloading during the process of karst collapse (during the construction stage) and ground collapse (during the mining stage) of the mine. Then, the surrounding rock mass progressively undergoes toppling failure and becomes unstable, making the region subjected to ground movement progressively extend outwards.

Esse livro se propõe a discutir como a vida ocorre em Umbaúba, um pequeno município do interior do estado nordestino de Sergipe. Em meio a discussões acaloradas sobre a importância dos programas sociais de distribuição de renda que mascara uma forte onda latente e sempre presente de racismo, busca-se demonstrar, de forma generalista, não apenas a importância de programas assistenciais públicos, mas também como a não reflexão sobre os municípios brasileiros por parte da Academia e da Sociedade pode impactar negativamente no acesso à qualidade de vida.

A new method for indirect calculation of the surface meridional velocity is presented. On the base of the known latitude function of the pressure an expression is found for the calculation of the mean meridional component of velocity in the winter season, including surface friction. Together with known values of the meridional wind in the higher levels the mean mass transport at the Northern Hemisphere in the planetary boundary layer is calculated. The computation shows that the mean meridional mass transport in the planetary boundary layer is southward and that it is greater than 2/3 of the total southward mass transport in the entire atmosphere. The mean vertical velocity is calculated from the continuity of the mass of air in the planetary boundary layer. The difference between measured and calculated meridional wind profile in the Ekman layer shows greater values in the lower latitudes than at higher ones. Ober die mittlere meridionale Zirkulation in der planetaren Grundschicht im Winter in der Nordhemisphiire Es wird eine neue Methode zur indirekten Berechnung der meridionalen Oberfl~ichengeschwindigkeit dargelegt. Auf Grund der bekannten Breitenabh~ingigkeit des Druckes wird eine Gleichung zur Berechnung der mittleren meridionalen Komponente der Geschwindigkeit im Winter mit Bemcksichtigung der Bodenreibung abgeleitet. Mit Beriicksichtigung der bekannten Werte des Windes in h6heren Schichten wird der mittlere Massentransport in der planetaren Grundschicht der Nordhemisph~re berechnet. Die Berechnung ergibt, dai~ dieser Massentransport gegen Stiden gerichtet ist und daf~ er gr6i~er ist als 2/3 des gesamten Massentransports nach Siiden in der ganzen Atmosph~ire. Die mitflere vertikale Geschwindigkeit wird aus der Kontinuit~t der Luftmasse in der planetaren Gmndschicht berechnet. Die Differenz zwischen gemessenem und berechnetem meridionalen Windproffl in der Ekman-Schicht weist in niedrigeren Breiten gr6t~ere Werte auf als in h6heren Breiten.

A new method for indirect calculation of the surface meridional velocity is presented. On the base of the known latitude function of the pressure an expression is found for the calculation of the mean meridional component of velocity in the winter season, including surface friction. Together with known values of the meridional wind in the higher levels the mean mass transport at the Northern Hemisphere in the planetary boundary layer is calculated. The computation shows that the mean meridional mass transport in the planetary boundary layer is southward and that it is greater than 2/3 of the total southward mass transport in the entire atmosphere. The mean vertical velocity is calculated from the continuity of the mass of air in the planetary boundary layer. The difference between measured and calculated meridional wind profile in the Ekman layer shows greater values in the lower latitudes than at higher ones. Ober die mittlere meridionale Zirkulation in der planetaren Grundschicht im Winter in der Nordhemisphiire Es wird eine neue Methode zur indirekten Berechnung der meridionalen Oberfl~ichengeschwindigkeit dargelegt. Auf Grund der bekannten Breitenabh~ingigkeit des Druckes wird eine Gleichung zur Berechnung der mittleren meridionalen Komponente der Geschwindigkeit im Winter mit Bemcksichtigung der Bodenreibung abgeleitet. Mit Beriicksichtigung der bekannten Werte des Windes in h6heren Schichten wird der mittlere Massentransport in der planetaren Grundschicht der Nordhemisph~re berechnet. Die Berechnung ergibt, dai~ dieser Massentransport gegen Stiden gerichtet ist und daf~ er gr6i~er ist als 2/3 des gesamten Massentransports nach Siiden in der ganzen Atmosph~ire. Die mitflere vertikale Geschwindigkeit wird aus der Kontinuit~t der Luftmasse in der planetaren Gmndschicht berechnet. Die Differenz zwischen gemessenem und berechnetem meridionalen Windproffl in der Ekman-Schicht weist in niedrigeren Breiten gr6t~ere Werte auf als in h6heren Breiten.

The site-percolation problem on a simple cubic lattice is studied by the Monte Carlo method. By combining results for periodic lattices of different sizes through the use of finite-size scaling theory we obtain good estimates forpc (0.3115 + 0.0005),/3 (0.41 4-0.01), 7 (1.6 4-0.I), and v (0.8 + 0.1). These results are consistent with other studies. The shape of the clusters is also studied. The average "surface area" for clusters of size k is found to be close to its maximal value for the low-concentration region as well as for the critical region. The percentage of particles in clusters of different sizes k is found to have an exponential tail for large values of k for p < pc. For p > Pc there is too much scatter in the data to draw firm conclusions about the size distribution.

Pollen records from large lakes have been used for quantitative palaeoclimate reconstruction, but the influences that lake size (as a result of species-specific variations in pollen dispersal patterns that smaller pollen grains are more easily transported to lake centre) and taphonomy have on these climatic signals have not previously been systematically investigated. We introduce the concept of pollen source area to pollen-based climate calibration using the north-eastern Tibetan Plateau as our study area. We present a pollen data set collected from large lakes in the arid to semiarid region of central Asia. The influences that lake size and the inferred pollen source areas have on pollen compositions have been investigated through comparisons with pollen assemblages in neighbouring lakes of various sizes. Modern pollen samples collected from different parts of Lake Donggi Cona (in the north-eastern part of the Tibetan Plateau) reveal variations in pollen assemblages within this large lake, which are interpreted in terms of the species-specific dispersal and depositional patterns for different types of pollen, and in terms of fluvial input components. We have estimated the pollen source area for each lake individually and used this information to infer modern climate data with which to then develop a modern calibration data set, using both the multivariate regression tree (MRT) and weighted-averaging partial least squares (WA-PLS) approaches. Fossil pollen data from Lake Donggi Cona have been used to reconstruct the climate history of the north-eastern part of the Tibetan Plateau since the Last Glacial Maximum (LGM). The mean Published by Copernicus Publications on behalf of the European Geosciences Union.

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Statistical characteristics are calculated for stationary velocity fluctuations in a one-dimensional open channel flow with a given vertical velocity profile and with one-dimensional irregular bottom waves, characterized by a spectral density function. The calculations are based on an approximate calculation of the velocity fluctuations in the fluid generated by a harmonic corrugation of the bottom. As linearized dynamical equations are used, the velocity fluctuations caused by random bottom disturbances may be obtained by superposition. The dynamics of the motion is assumed to be governed by the Orr-Sommerfeld equation representing the internal wave motion in the fluid. This equation is solved in an approximate manner by reducing it in the upper layer of the fluid to the Rayleigh equation. Close to the bottom we simplify it to a shape still containing the essentials of the viscous behaviour of the flow. Numerical examples and a tentative qualitative comparison with experimental data are given.

Hot carrier injection (HCI) degradation is evaluated for n-metal oxide semiconductor (MOS) and pMOS high-κ-fin shaped field effect transistor with (100) and (110) sidewall surface orientations. It was found that impact ionization at the source, in addition to the traditional drain side enhances HCI degradation for the Vg=Vd condition. The degradation increases with decreasing fin length, with negligible dependence on substrate orientation.

As a part of the PM 2.5 Technology Assessment and Characterization Study-New York (PMTACS-NY), concentrations of sulfate and 15 trace elements were determined in daily PM 2.5 samples collected from July 2001 to September 2002 at a site in urban Queens, NY. The elements were Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Cd, Sb, and Pb. Over the first 12 months these elemental concentrations were measured in both a water extract and in a total acid digestate so that the solubility of the aerosols bearing the above trace elements could be evaluated. This is important as elements with high solubility can be more readily bio-activated in the lungs and thus may be potentially more harmful to humans. An overview of the elemental composition of PM 2.5 aerosols at the Queens, NY site over the 15-month period is presented. This includes a comparison of seasonal changes in aerosol composition and solubility at the sites along with an evaluation of the impacts on aerosol composition of the collapse of the World Trade Center Towers in Manhattan on 9/11/2001 and the smoke from Quebec wildfires in early July 2002.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

The EUREQUA project raises the issue of the definition and evaluation of the environmental quality of neighbourhoods. The approach consists of integrating and cross-referencing observable data characterising the physical environment and people's perception of their quality of life. The study area is a neighbourhood in Toulouse (France) with high social and typomorphological diversity, subject to noise and air pollution nuisances. Three 3-day field campaigns were organised in January, April, and June 2014. Instrumented and commented walks took place three times per day. For each one, measurements of physical environmental parameters and surveys were performed simultaneously at six locations in the neighbourhood. The study focuses on microclimate and thermal comfort issues. It aims to compare in situ meteorological data of air temperature, humidity, wind speed, and mean radiant temperature, with quantitative results rating human perception of heat, humidity, wind, and thermal comfort. The variability in perception and measurements is mainly driven by seasonal effects, especially for heat and humidity, and, to a lesser extent, for wind. Wind perception and measurement also vary spatially, thus highlighting site effects. Linear models indicate a positive link between heat perception and mean radiant temperature, as well as between wind perception and mean and standard deviation of wind speed (with a higher sensitivity of people to wind under winter climate conditions). Finally, it is found that perception of thermal comfort is only slightly linked to the different microclimate dimensions, and is rather driven by other appreciation factors and emotional criteria related to the general environmental quality of the study area.

Atmospheric water demand drives forest evaporation controlled by the plant physiological properties within available moisture storage thresholds. The pattern and magnitude of African Miombo Forest transpiration across dry season canopy phenophases are unknown. This is because estimating forest evaporation in African ecosystems continues to be a challenge as flux observation towers are scant, if not completely lacking in most ecosystems like the Miombo Forest, one of Africa's largest woodland formations. Moreover, in the Miombo Forest, satellite databased evaporation products (i.e., GLEAM, MOD16, SSEBop and WaPOR) show significant discrepancies in both 20 pattern and amounts of evaporation especially during the dry season canopy phenophases. Despite the main limitations with estimation of forest evaporation the development and application of the distributed temperature sensing (DTS) system is providing deepened insights and improved accuracy in forest energy partitioning for evaporation assessment. In this study the Bowen ratio distributed temperature sensing (BR-DTS) approach is used to partition available energy and estimate evaporation across three Miombo Forest canopy phenophases covering the entire 2021 dry season and early rain season. Furthermore, four satellite evaporation products are compared to the field observations. Results show that evaporation appears to follow the net radiation and air temperature pattern with the lowest values observed during the most net radiation and air temperature depressed periods and highest values during the peak net radiation and air temperature. Evaporation continues to rise even during the driest period in the dormant leaf phenophase when canopy cover is said to be at its minimum. This is possibly facilitated by the 30 retention of about 70 percent canopy cover during the dry season which transpires within the adapted thresholds constrained by physiological properties of each Miombo Forest species with access to ground water and vegetative water storage. This goes to show that during the dry season Miombo species may not be as water stressed as imagined. When compared to field observations all four-satellite evaporation products underestimate evaporation with only the WaPOR showing a similar pattern of evaporation during the dry season. The differences between field observations and satellite-based evaporation products can be attributed to the model structure, processes as well as inputs.

The rapid development of cities has led to the urban sprawl to the suburbs. Studies have shown that urban sprawl leads to the increasing intensity of heat island effect. This paper, based on the DMSP/OLS nighttime light data and the MODIS land surface temperature data during the years 2000, 2005, and 2013, discussed the spatial and temporal characteristics of urban sprawl, urban heat island intensity in China, and their relationship, respectively. The results show that (1) the national urban expansion index showed an upward trend. The urban area was 104,000 km 2

Abstract: MODerate Resolution Imaging Spectroradiometer (MODIS) aerosol retrievals over the North Atlantic spanning seven hurricane seasons are combined with the Statistical Hurricane Intensity Prediction Scheme (SHIPS) parameters. The difference between the current and future intensity changes were selected as response variables. For 24 major hurricanes (category 3, 4 and 5) between 2003 and 2009, eight lead time response variables were determined to be between 6 and 48 h. By combining MODIS and SHIPS data, 56 variables were compiled and selected as predictors for this study. Variable reduction from 56 to 31 was performed in two steps; the first step was via correlation coefficients (cc) followed by Principal Component Analysis (PCA) extraction techniques. The PCA reduced 31 variables to 20. Five categories were established based on the PCA group variables exhibiting similar physical phenomena. Average aerosol retrievals from MODIS Level 2 data in the vicinity of UTC 1,200 and 1,80...

The rapid development of cities has led to the urban sprawl to the suburbs. Studies have shown that urban sprawl leads to the increasing intensity of heat island effect. This paper, based on the DMSP/OLS nighttime light data and the MODIS land surface temperature data during the years 2000, 2005, and 2013, discussed the spatial and temporal characteristics of urban sprawl, urban heat island intensity in China, and their relationship, respectively. The results show that (1) the national urban expansion index showed an upward trend. The urban area was 104,000 km 2

Many regions of the world have experienced dramatic changes in occurrence of heat waves. Investigating changes in their spatial patterns is of great importance for understanding the causes of heat waves and their related processes. This paper, based on observation data collected from 611 meteorological stations, used the weighted mean center tool in ArcGIS to calculate China's heat wave center of gravity and to trace its migration over the past five decades. The results show an association between its north-south movements and the change of Arctic Oscillation Index, especially for the period after the mid-1980s, during which substantial north-south displacements took place. This study also revealed a close relationship between its west-east movements and the change in annual number of heat wave days before the 1990s, after which it was replaced by a timedependent relationship that showed increasing heat wave trend only.

Dust monitoring is one of the most challenging issues in today's aerosol remote sensing. Aerosol loading of dust predominantly in the arid regions is highly variable and thus poses challenges that are several magnitudes larger while compared to the monitoring of continental aerosols. This paper addresses the time varying aspects of the Saharan dust. A time series analysis from 2002-2013 of the Saharan dust region using multi-sensor measurements is done to capture the dust transport mechanisms that have been proven to have far reaching consequences in shaping the climatology of the Northern Atlantic region. Based on over decadal measurement datasets it was found that temporal and amount of dust transport were found to be a chief catalyst in the large number of storm systems (28) that occurred in 2005. Similarly, a time lag, slight change in spatial location, coupled with a reduction in the amount of dust transport had reduced the number of storm systems (11) that occurred in 2009. Relationship studies of the surface air temperatures and Aerosol Optical Thickness (AOT) over the study area showed a reduction in the correlation between the two geophysical parameters in 2005 compared to 2009. This means the large AOT values tended to slightly decrease the surface air temperatures. This also gave an idea of the location in terms of height of the dust to be in the upper troposphere and lower stratosphere (approximately between 2 km -4 km above ground surface).

Wildfires can lead to severe environmental consequences by releasing large amounts of particulate matter (PM) and precursors of ozone (Sandberg et al., 1999; Riebau and Fox, 2001). The Southeast has the most burned area among various US regions (Stanturf et al., ...

This paper presents the first field, geochemical and geophysical information on the recently recognized Early Cretaceous Balud Ophiolitic Complex (BOC) in the island of Masbate in the Central Philippines. Mapping of the western limb of the island revealed that only the upper crustal section of the BOC is exposed in this area. Geochemically, the pillow basalts are characterized by transitional mid-oceanic ridge basalt-island arc tholeiitic compositions. Gravity surveys yielded low Bouguer anomaly values that are consistent with the highly dismembered nature of the BOC. Short wavelength, high amplitude magnetic anomalies registered across the study area are attributed to shallow magnetic sources. This is taken to support the model that the ophiolitic complex occurs as thin crustal slivers that are not deeply-rooted in the mantle. Comparing BOC with other ophiolites in the Central Philippines, such as those in the islands of Sibuyan, Leyte and Bohol, suggests the possibility of a common or contiguous source for similarly-aged and geochemically composed crust-mantle sequences in the region.

Two oil particle trajectory forecasting systems were developed and applied to the 2010 Deepwater Horizon Oil Spill in the Gulf of Mexico. Both systems use ocean current fields from high-resolution numerical ocean circulation model simulations, Lagrangian stochastic models to represent unresolved sub-grid scale variability to advect oil particles, and Monte Carlo-based schemes for representing uncertain biochemical and physical processes. The first system assumes two-dimensional particle motion at the ocean surface, the oil is in one state, and the particle removal is modeled as a Monte Carlo process parameterized by a one number removal rate. Oil particles are seeded using both initial conditions based on observations and particles released at the location of the Maconda well. The initial conditions (ICs) of oil particle location for the two-dimensional surface oil trajectory forecasts are based on a fusing of all available information including satellitebased analyses. The resulting oil map is digitized into a shape file within which a polygon filling software generates longitude and latitude with variable particle density depending on the amount of oil present in the observations for the IC. The more complex system assumes three (light, medium, heavy) states for the oil, each state has a different removal rate in the Monte Carlo process, three-dimensional particle motion, and a particle size-dependent oil mixing model.

Two oil particle trajectory forecasting systems were developed and applied to the 2010 Deepwater Horizon Oil Spill in the Gulf of Mexico. Both systems use ocean current fields from high-resolution numerical ocean circulation model simulations, Lagrangian stochastic models to represent unresolved sub-grid scale variability to advect oil particles, and Monte Carlo-based schemes for representing uncertain biochemical and physical processes. The first system assumes two-dimensional particle motion at the ocean surface, the oil is in one state, and the particle removal is modeled as a Monte Carlo process parameterized by a one number removal rate. Oil particles are seeded using both initial conditions based on observations and particles released at the location of the Maconda well. The initial conditions (ICs) of oil particle location for the two-dimensional surface oil trajectory forecasts are based on a fusing of all available information including satellitebased analyses. The resulting oil map is digitized into a shape file within which a polygon filling software generates longitude and latitude with variable particle density depending on the amount of oil present in the observations for the IC. The more complex system assumes three (light, medium, heavy) states for the oil, each state has a different removal rate in the Monte Carlo process, three-dimensional particle motion, and a particle size-dependent oil mixing model.