Atmospheric sciences

The extensive work on the increasing burden of aerosols and resultant climate implications shows a matter of great concern. In this study, we investigate the aerosol optical depth (AOD) variations in the Indian Himalayan Region (IHR) between its plains and alpine regions and the corresponding consequences on the energy balance on the Himalayan glaciers. For this purpose, AOD data from Moderate Resolution Imaging Spectroradiometer (MODIS, MOD-L3), Aerosol Robotic Network (AERONET), India, and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) were analyzed. Aerosol radiative forcing (ARF) was assessed using the atmospheric radiation transfer model (RTM) integrated into AERONET inversion code based on the Discrete Ordinate Radiative Transfer (DISORT) module. Further, air mass trajectory over the entire IHR was analyzed using a hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. We estimated that between 2001 and 2015, the monthly average A...

Ground based measurement of aerosol optical depth (AOD) and black carbon (BC) aerosol were carried out on the foothills of the three important selected glaciers (i.e., Parbati, Hamta and Beas Kund) in winter season in the northwestern Indian Himalayan Region. The AOD values were found to be in the range of 0.05-0.19. The aerosol loading was observed relatively to be higher (0.15) on 10 November 2014. Besides the biomass burning and frequent incidents of forest fire at local levels, long-range transportation of aerosol particles by air mass from the desert region also contribute to aerosol loading at observing sites. The average value of BC concentration ranges from 283 to 2026 ng m -3 . BC concentration increases more than three times during morning and evening compared to night hours, in addition to shallow boundary layer and a larger possibility of BC intrusion from it during morning and evening. Variations of BC shows high concentration during winter dry season associated with the air masses predominantly coming from Indian plain rich in carbonaceous aerosols. The BC concentration is found to have relationship with anthropogenic activities, fossil fuel burning and biomass burning which has been observed in past in this region.

Aerosol parameters are measured using a ground-based Multi-wavelength Radiometer (MWR) at Mohal (31.90 • N, 77.11 • E, 1154 m amsl) in the Kullu valley during clear sky days of a seasonal year. The study shows that the values of spectral aerosol optical depths (AODs) at 500 nm and the Ångstrom turbidity coefficient 'β' (a measure of columnar loading in atmosphere) are high (0.41 ± 0.03, 0.27 ± 0.01) in summer, moderate (0.30 ± 0.03, 0.15 ± 0.03) in monsoon, low (0.19 ± 0.02, 0.08 ± 0.01) in winter and lowest (0.18 ± 0.01, 0.07 ± 0.01) in autumn, respectively. The Ångstrom wavelength exponent 'α' (indicator of the fraction of accumulation-mode particles to coarse-mode particles) has an opposite trend having lowest value (0.64 ± 0.06) in summer, low (0.99 ± 0.10) in monsoon, moderate (1.20 ± 0.15) in winter and highest value (1.52 ± 0.03) in autumn. The annual mean value of AOD at 500 nm, 'α' and 'β' are 0.24 ± 0.01, 1.06 ± 0.09 and 0.14 ± 0.01, respectively. The fractional asymmetry factor is more negative in summer due to enhanced tourists' arrival and also in autumn months due to the monthlong International Kullu Dussehra fair. The AOD values given by MWR and satellite-based moderate resolution imaging spectro-radiometer have good correlation of 0.76, 0.92 and 0.97 on diurnal, monthly and seasonal basis, respectively. The AODs at 500 nm as well as 'β' are found to be highly correlated, while 'α' is found to be strongly anti-correlated with temperature and wind speed suggesting high AODs and turbidity but low concentration of fine particles during hot and windy days. With wind direction, the AOD and 'β' are found to be strongly anti-correlated, while 'α' is strongly correlated.

Investigations of aerosol optical and physical characteristics using the application of Ångström formula and second order polynomial fit were carried out from April 2006 to March 2009 at Mohal in the Kullu valley. The measurements of spectral aerosol optical depths (AODs) were conducted using multiwavelength radiometer (MWR). The AOD at 0.5 μm wavelength on daily basis (mean ± standard deviation) for the entire three-year study period is obtained as 0.24 ± 0.08. Seasonal variations show the highest AOD at 0.5 μm wavelength with ∼0.34 ± 0.08 during pre-monsoon (April-July), followed by ∼0.26 ± 0.08 during monsoon (August-September), ∼0.21 ± 0.05 during post-monsoon (October-November) and ∼0.20 ± 0.07 during winter (December-March). The seasonal values indicate that the AOD at 0.5 μm wavelength is decreasing from pre-monsoon to winter with a notable reduction around 41%. The Ångström parameters using least square method is not found appropriate for size distribution particularly when coarse mode aerosols dominate. The coefficients of second order polynomial fit are more appropriate for the discrimination of aerosol size or irrespective to the dominance of either of the aerosols size. The difference in coefficient of polynomial fit is used to get confirmation on the dominant mode during different seasons. Study reveals that about 93%, 72% and 59% of AOD spectra are dominated by a wide range of fine mode fractions or mixture of modes during post-monsoon, winter and monsoon, respectively. On the other hand, during pre-monsoon, 72% of AOD spectra are found to be dominated by coarse mode aerosols.

The present study deals with the aerosol optical property which carried out during April 2006 to March 2007 over Mohal (31.9°N, 77.12°E) in the northwestern Indian Himalaya. The study was conducted using ground based Multi-wavelength Radiometer (MWR) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The daily average aerosol optical depth (AOD) at 500 nm was found to be (mean ± standard deviation) 0.24 ± 0.10. The afternoon AOD values have been noticed to be higher than the forenoon AOD values. Spectral AOD values exhibited larger day-to-day variation in finer aerosols during the observation period. The daily average value of Ångström exponent 'α' and turbidity coefficient 'β' obtained was 1.10± 0.38 and 0.12 ± 0.08 respectively. Higher value of AOD ~0.39± 0.06 during summer associated with low α ~0.73± 0.28 has attributed to the increase in the relative dominance of coarse size particles. In winter α ~1.21± 0.32 indicating a considerable increase in fine size particles, attributed to the anthropogenic activities. The AOD spectra seem to be more wavelength dependent in winter as compared to summer. Comparison of MWR observation with MODIS observation indicates a good conformity between ground-based and satellite derived AOD. The root mean square deviation (RMSD), mean absolute bias deviation (MABD) and correlation coefficient have been found to be ~0.08, ~0.06 and ~0.77 respectively. These results suggest that the AOD retrieval through satellite can be able to characterize AOD distribution over Mohal. However, further efforts to eliminate systematic errors in the existing MODIS products are needed. During the observation period ~30%, ~47% and ~62% air parcels drawn at 4000, 5500 and 8000 m above ground level respectively reached at Mohal which passed through or originated from The Great Sahara. The maximum AOD at 500 nm occurred on 8 May 2006. This has caused a significant reduction in surface reaching solar irradiance by ~59 Wm -2 . The back trajectory analysis suggested that the highest AOD during summer is due to high degree of human interference in the form of tourism and dust transport from the country lying in the northwestern part of India.

Las observaciones de un radiómetro de longitud de onda múltiple (MWR, por sus siglas en inglés) ubicado en tierra en el valle Kullu en la región noroccidental del Himalaya, de abril de 2007 a marzo de 2008, muestran que la profundidad óptica espectral del aerosol (AOD, por sus siglas en inglés) y el coeficiente Ångstr?m de turbidez (β) son altos durante la estación del monzón, ligeramente menores en el verano, bajos en invierno y los más bajos en otoño, para días claros, neblinosos y parcialmente claros, mientras que el exponente Ångstr?m de longitud de onda (α) tiene una tendencia opuesta. Los valores promedio anuales de AOD a 5000 nm son 0.25 ± 0.01, 0.46 ± 0.02 y 0.28 ± 0.02, para días de cielos claros, nebulosos y parcialmente claros, respectivamente. Los valores correspondientes para β son 0.13 ± 0.01, 0.22 ± 0.01 y 0.15 ± 0.01 y los de α 1.09 ± 0.04, 1.18 ± 0.03 y 0.89 ± 0.05. La α es ligeramente mayor pero la β es considerablemente más alta en los días nebulosos que en los claros, indicando que la niebla montañosa es rica en partículas gruesas. Hay una buena concordancia entre los valores MWR y los AOD satelitales de MODIS, con coeficientes de correlación anuales de 0.89, 0.70 y 0.81 para días claros, nebulosos y parcialmente claros, respectivamente. La correlación entre AOD a 500 nm y el coeficiente β con la temperatura, velocidad del viento y humedad es significativamente positivo, mientras que el del exponente α es negativo para la mayoría de los días, lo que sugiere alto AOD y turbidez pero baja concentración de partículas finas en días calientes, húmedos y con viento y viceversa. Asimismo, la correlación entre AOD a 500 nm y el coeficiente β con la dirección del viento es la mayoría de las veces negativa, mientras que la del exponente α es positiva, indicando que AOD y la turbidez disminuyen pero la concentración de partículas finas aumenta al cambiar la dirección del viento más hacia el sur de nuestro sitio. Así, durante el periodo analizado, los vientos que se dirigen hacia nuestro sitio desde las planicies indogangéticas son ricos en partículas gruesas, mientras que los vientos de la dirección sur o del desierto Thar transportan principalmente partículas finas.

Sizc!-se parated atmospheric aeroso ls were co llec ted at Kothi (a hill top) and M ohal (a va lley). situated at tho.: foo thill s of western Himalayas during th e summer sea son o f 1999. Bimodal di stributi on of aerosols was observed ::11 both the locat ions. Howeve r. at K othi . fin e si ze parti cles dominated (62 %). wherea s at Mohal . coa rse si ze parti cles co ntributed more (75 "/r•). Th e S0 4 and 0 3 panic le togeth er co ntributed -30% o f the total measured chemical co mposit ion o f aerosols. Burning of biomass and emi ssions from touri st ve hicles could be th e mai n loca l sources for these com ponent s. Ho'' ever. aeroso ls showed alkaline nature (L:•L:+ rati o< I ) clue to th e neutrali zing effec t of so me ca ti ons such as Ca and NH 4 .

The measurements using a ground based multi wavelength radiometer (MWR) at Mohal (31°54′N, 77°07′E, 1154 m AMSL) in the Kullu valley of Northwestern Himalayan region show that the spectral aerosol optical depth (AOD) and turbidity coefficient, β, are high in summer, moderate in monsoon season, low in winter and lowest in autumn, while wavelength exponent, α, has an opposite trend. Average annual value of AOD at 500 nm is 0.24±0.01, 0.43±0.02, and 0.28±0.02; that of β is 0.14±0.01, 0.22±0.02, and 0.17±0.03; and that of α is 1.06±0.09, 1.16±0.10, and 0.86±0.13, respectively, for clear, hazy and partially clear sky days. The considerably greater value of β on hazy days indicates more coarse particles in mountain haze. The fractional asymmetry factor (AF) is more negative in summer and autumn months. The AOD and β have significantly positive correlation with temperature and wind speed, suggesting high AODs and turbidity on hot and windy days.

In stitut e of Tropi cal M eteoro logy . Dr Homi I3habha Road. Pa shan. Pun e 41 10m:. India and Kh wai rakpalll Gajananda Shriralllinstillite for Indu strial Resea rch. Env iro nment Protccti on Di vision. 1<). Uni ve rsity Roaci. Delhi liD 007. India O.f; rel'i.l'et/ 20 April 2005 ; ({('ceIJ/l'd 14 Jlllle 2005 Tota l suspended particu lat e (TS P) matter on fortni ght ly basis throu ghou t th e: year and Illass si ze: distri buti on of aerosob as we l l as ultrafine: aeroso ls un week ly ba sis in th e Illonth s of May and June lVe re monitored during I <)<)6-2003 at dilTerent alti tu dinal locations of th e Kullu -M anali touri st co mpl ex in the: nort hwestern Himalaya. Conce ntrati on of TSP ra nged frolll 35.8 (A ugus t I <)l)6) to 207 .3 f1,g nf-' (Julle 2003) at Mohal II 150 m from ave rage: se a level (AS L ) I and from 31.7 (Ju ly 2003) to 23l) f1, g m'-' (A pril 200 I ) at Manali (2050 III ASL). Th e mass size di stribut ion o f aeroso ls showed a bimodal distribution hav ing onc peak in the coa rse size ra nge (3.3-l) f1, m dial and the oth er in th e finc size mnge (0.OX-2. 1 f1,1ll dial at both th e loca ti ons. Ultrafi ne aerosol (UA) (O'( )OI -O.1 f1,m radiu s) co nce ntrati ons we rc found to be hi ghes t at th e lowest experim ental altiwde site (M ohal) and l'ice 1'1' 1'.1'0. The diurn al variati on of UA co ncent rati oll for three yea rs showed lh at the conce ntrati on ranges from 2640 (a t 0500 hI'S LT) to 5 160 N umber (N) cm'-' (at 1300 hI'S L T) at M ohal and from 400 (a t 0400 Ill'S LT) to 2 1l)O N cm' .1 (at 1300 hI'S L T) at Koth i. On an ave rage. TSP crossed its permi ssib le limit set by National Ambielll Air Qua lit y Stand ard (NAAQS) leve l in th e sensiti ve area s such as Kullu -Manali hill spots. Bi modal nallire r Illass si ze dis tributi on indi cates tw o importalll sources co ntri bu tin g in total aerosols-th e fin e mode. primaril y due to anthropogenic act i vities and the coarse mode aeroso ls. mainl y due to natu ral ,ources. La rge number o f' co nce ntrati on o f ultrafine parti cles indicates th e presencc of air pollutants more <1 tl ow altitucies as co mpared to hi gh altillides. Keywords: Aerosols' beh av iour. To tal suspended particulate,. Mass size distri bu ti on. Ultrafinc aerosols. Kull u-Mana li touri st co mplex, North wes tern Himalaya

Frequent repair and reconstruction activities required on existing pavements lead to significant expenses for highway agencies and road users. Economic loss and inconveniences resulting from frequent road maintenance and rehabilitation activities led researchers and practitioners to seek pavement alternatives that have longer service lives and, at the same time, have lower life-cycle costs. One such alternative developed by the asphalt industry was the design and construction of perpetual pavements. Several studies have compared conventional pavements to perpetual pavements, focusing primarily on construction, maintenance, and rehabilitation-related financial costs. With environmental sustainability gaining importance as a component of decision-making processes, it is critical to compare the environmental impacts of these pavement alternatives. This paper uses life cycle assessment (LCA) to accomplish this objective. This paper also focuses on studying the benefits that will ensue from the combination of reduced-temperature warm mix asphalt (WMA) and perpetual pavement concepts. Therefore, alternatives considered in this study include: (1) a hot mix asphalt (HMA) conventional pavement, (2) an HMA perpetual pavement, and (3) a WMA perpetual pavement. AASHTO 1993, PerROAD, and TxME were used to design the pavement structures. The LCA was carried out over a 50-year analysis period, and it involved all cradle-to-grave life cycle stages of a pavement, excluding the use phase. The maintenance and rehabilitation of the pavements were scheduled based on performance prediction results. Opting for a hot-perpetual pavement instead of a hot-conventional pavement resulted in lower environmental impacts in all five impact categories considered. Moreover, when the perpetual pavement was constructed using WMA instead of HMA, further improvements in three out of the five impact categories were realized.

Stochastic parameterization has become commonplace in numerical weather prediction (NWP) models used for probabilistic prediction. Here a specific stochastic parameterization will be related to the theory of stochastic differential equations and shown to be affected strongly by the choice of stochastic calculus. From an NWP perspective the focus will be on ameliorating a common trait of the ensemble distributions of tropical cyclone (TC) tracks (or position); namely, that they generally contain a bias and an underestimate of the variance. With this trait in mind the authors present a stochastic track variance inflation parameterization. This parameterization makes use of a properly constructed stochastic advection term that follows a TC and induces its position to undergo Brownian motion. A central characteristic of Brownian motion is that its variance increases with time, which allows for an effective inflation of an ensemble’s TC track variance. Using this stochastic parameterizat...

In this paper l{ossby wave frequenciPs and group velocitiPs are analyzed for various finitP elPment and finite diffPrence approximaJiorrn to the vorticity-divergence form of the shallow •water eaquations. Also included a.re finite difference solutions for the primitive equations for the staggered grids B and C from \Vajsowicz and for the unstaggcrcd grid A. The result;,; arc pre;scntcd for three ratio:,< bct>vccn 1.hc grid 8izc and the l{ossby radius of deformation. The vorticity-divergence equation schemes givP supPrior solutions to those based on thP primitive equations. The lwst results come from thP finite element schemes that use linear basis functions on isosceles triangles and bilinear functions on rectangles. All of the primitive equation finite difference schemes have problem;,; for at least. one Ro;,;;,;by deformation-grid size ratio.

ABSTRACTWhile seasonal outlooks have been operational for many years, until recently the extended‐range timescale referred to as subseasonal‐to‐seasonal (S2S) has received little attention. S2S prediction fills the gap between short‐range weather prediction and long‐range seasonal outlooks. Decisions in a range of sectors are made in this extended‐range lead time; therefore, there is a strong demand for this new generation of forecasts. International efforts are under way to identify key sources of predictability, improve forecast skill and operationalize aspects of S2S forecasts; however, challenges remain in advancing this new frontier. If S2S predictions are to be used effectively, it is important that, along with science advances, an effort is made to develop, communicate and apply these forecasts appropriately. In this study, the emerging operational S2S forecasts are presented to the wider weather and climate applications community by undertaking the first comprehensive review...

Honeydew honey has differentiated chemical and physicochemical characteristics besides potential functional properties such as antimicrobial, anti-inflammatory and antioxidant. In this sense, the interest and consumption of this honey as a functional product by the food industry and consumers have increased. Honeydew honeys usually present dark color, a lower content of monosaccharides and higher values of pH, acidity, electric conductivity, proteins, minerals, phenolic compounds, and oligosaccharides compared to blossom honeys, which contribute to its outstanding biological activities. Consequently, contaminations and adulterations of this honey can occur and compromise the quality, safety and authenticity of honeydew honey. Thus, detailed knowledge of the composition and properties of honeydew honeys is of great importance, especially considering that honeydew honeys are still few studied and therefore underestimated. Therefore, in this review, the physicochemical characteristics, chemical and bioactive composition, functional and health-promoting properties of honeydew honey as well as contamination, adulteration and authenticity of this honey are summarized.

This paper explores the hypothesis that electromagnetic fields can serve as both energy source and organizational template for complex self-organizing systems. Using data from NASA's Juno mission, we analyze Jupiter's Great Blue Spot (GBS) and related magnetic anomalies for evidence of field-based organizational processes. We identify key characteristics suggesting proto-metabolic behavior: (1) autonomous energy cycling through documented oscillatory patterns, (2) coherent energy transfer mechanisms, (3) field-matter energy exchange, (4) self-organizing torsional oscillations, (5) adaptive behaviors in response to environmental changes, and (6) evidence of pattern propagation across multiple magnetic structures. Additionally, we examine the interactions between these magnetic anomalies, including a ribbon-like structure that follows Jupiter's magnetic equator and potentially connects discrete magnetic structures. These findings align with predicted characteristics of complex electromagnetic organization and suggest that Jupiter's magnetosphere may harbor an ecosystem of field-based structures. This provides a new framework for understanding potential electromagnetic complexity and expands our conception of organized systems beyond conventional biochemistry.

The horizontal irradiance at the sea surface is an informative light pollution indicator to study Artificial Light at Night (ALAN) effects on marine biodiversity (e.g.: zooplankton diel vertical migration). The Posch ratio (PR) for the horizontal irradiance (that is, the ratio of the horizontal irradiance to the zenith radiance) is a useful tool for estimating the irradiance from easily available measurements of the zenith night sky brightness. The PR definition has already been generalized for any pair of linear radiance indicators in any pair of arbitrarily chosen photometric bands, and can also be applied to estimate e.g. the average sky radiance or the radiance at some elevation above the horizon as a function of the radiance in any other direction of the sky. The PR for a single light source depends on the distance from the source, its angular and spectral emission pattern, and the state of the atmosphere. The PR for any set of sources is a linear combination of the individual PRs that each one would produce separately, with weights that can be easily derived from the relative contribution of each source to the zenith radiance. Whereas in populated lands the ALAN PR varies relatively fast from one location to another, due to the particular spatial distribution of lights, in coastal waters and the high seas the light pollution PR is a smooth function of the distance to the shoreline, due to the progressive lack of neighboring sources and the absence of obstacles. In this work we present the fundamental equations of the model and an example of application for the waters surrounding the Iberian Peninsula, North Africa and the West Mediterranean islands.

In The border city of Oujda (Moroccan-Algerian border /east of Morocco), and in order to monitor the tropospheric ozone (O 3) levels, two sampling campaign of stratospheric ozone have been carried between 04/2013 and 01/ 2014 out on an hourly base with the use of an automatic ozone analyzer device using the UV absorption technology. This article provides O 3 results to incorporate into reports and research studies. The monitoring of O 3 levels in the ambient air of Oujda during warm and the cold seasons respectively is needed, justified, discussed and interpret the O 3 measurements. During the warm season 60.07% of the recorded values are below the Moroccan limits and 41.1% are below world health organization limits, in the second sampling campaign (in cold season) 92% of the recorded values are below the Moroccan limits and 84.6% are below world health organization limits. This article provides background information on O 3 formation, sources, and a comprehensive review of probable...

Understanding air exchange dynamics between underground cavities (e.g., caves, mines, boreholes, etc.) and the atmosphere is significant for the exploration of gas transport across the Earth-atmosphere interface. Here, we investigated the role of atmospheric conditions in controlling air transport inside boreholes using in situ field measurements. Three geometries were explored: (1) a narrow and deep shaft (0.1 m wide and 27 m deep), ending in a large underground cavity; (2) the same shaft after the pipe was lowered and separated from the cavity; and (3) a deep large-diameter borehole (59 m deep and 3.4 m wide). Absolute humidity was found to be a reliable proxy for distinguishing between atmospheric and cavity air masses (mainly during the winter and spring seasons) and thus to explore air transport through the three geometries. Airflow directions in the first two narrow-diameter geometries were found to be driven by changes in barometric pressure, whereas airflow in the large-diameter geometry was correlated primarily with the diurnal cycles of ambient atmospheric temperature. CO 2 concentrations of ∼ 2000 ppm were found in all three geometries, indicating that airflow from the Earth's subsurface into the atmosphere may also be significant in the investigation of greenhouse gas emissions.

This article introduces the second generation CMCC Earth System Model (CMCC‐ESM2) that extends a number of marine and terrestrial biogeochemical processes with respect to its CMIP5 predecessor. In particular, land biogeochemistry was extended to a wider set of carbon pools and plant functional types, along with a prognostic representation of the nitrogen cycle. The marine ecosystem representation was reshaped toward an intermediate complexity of lower trophic level interactions, including an interactive benthic compartment and a new formulation of heterotrophic bacterial population. Details are provided on the model setup and implementation for the different experiments performed as contribution to the sixth phase of the Coupled Model Intercomparison Project. CMCC‐ESM2 shows an equilibrium climate sensitivity of 3.57°C and a transient climate response of 1.97°C which are close to the CMIP5 and CMIP6 multi‐model averages. The evaluation of the coupled climate‐carbon response in the h...

Most available climate/weather stations (e.g., COOP stations) are located in valleys. The few high elevation stations we have (RAWS, SNOTEL) and are relatively sparse, so do not adequately capture temperature variation in steep complex topography. There is growing awareness of just how much information current air temperature models are missing in complex mountainous terrain. For example, cold air drainage and lapse rates vary from night to night. Many terrestrial management decisions (tree planting, growth and yield, species occurrence, etc.) are made at the stand or aspect scale, due to variation in solar insolation, and temperature predictions must match that scale in order to be useful for site-level predictions. For aquatics applications, one of the most important questions is understanding the mechanisms associated with how streams warm up & whether that information can be used to predict which types of streams will be more/less sensitive to future changes. As a result, there is growing interest in using inexpensive sensors to develop massive air temperature monitoring arrays in mountains. We are now beginning to make progress in using sensor networks to empirically downscale temperatures in complex topography (see Holden et al. (2011); Holden et al. (in press); and attachments). However, there are some real challenges to accurately measuring air temperature in forested environments. I'm now in my 3 rd year of deploying air sensor arrays across the northern Rockies, I've learned a lot mainly from mistakes that I've made and will try to share some of that information here (see attachment on tradeoffs). In short, it's a significant challenge to measure air temperature accurately but it's also a very important to try and minimize bias associated with solar radiation. Note that we are inherently dealing with a highly modified radiation environment, because of the presence of trees and vegetation, which all absorb and re-emit radiation. In the end, as a user community, ecologists and climatologists should work toward standardizing our methods for monitoring air temperatures in forested environments. I don't claim to have all the answers, but if interested in discussing further or if you'd like more information on our radiation shield design, you can contact me at:

This research mainly focuses on the transport and dispersion of chemical agent plume according to the Lagrangian Puff Model and Lagrangian Particle Model of NBC_RAMS(Nuclear, Biological, Chemical Reporting And Modeling S/W System). NBC_RAMS was developed with the purposes of estimating the fate of Chemical, Biological, and Radioactive(CBR) agent plumes and evaluating damages in the Republic of Korea. First, it calculates the local weather pattern, i.e. wind speed, wind direction, and temperature, by considering the effects of land uses and topography. The plume behaviors are calculated by adopting the Lagrangian Puff Model(LPFM) or Lagrangian Particle Model(LPTM). In this research, we assumed a virtual chemical agent exposure event in a stable atmospheric condition during the summer season. The plume behaviors were estimated by both LPFM and LPTM on the used area(urbanized and dry area) and the agricultural land. The higher heat flux in the used area led to stronger winds and further downward movement moving of the chemical agent than the farmland. The lateral dispersion of the chemical plume was emphasized in the Lagrangian Puff Model because it adopted Gaussian distribution.

This research mainly focuses on the transport and dispersion of chemical agent plume according to the Lagrangian Puff Model and Lagrangian Particle Model of NBC_RAMS(Nuclear, Biological, Chemical Reporting And Modeling S/W System). NBC_RAMS was developed with the purposes of estimating the fate of Chemical, Biological, and Radioactive(CBR) agent plumes and evaluating damages in the Republic of Korea. First, it calculates the local weather pattern, i.e. wind speed, wind direction, and temperature, by considering the effects of land uses and topography. The plume behaviors are calculated by adopting the Lagrangian Puff Model(LPFM) or Lagrangian Particle Model(LPTM). In this research, we assumed a virtual chemical agent exposure event in a stable atmospheric condition during the summer season. The plume behaviors were estimated by both LPFM and LPTM on the used area(urbanized and dry area) and the agricultural land. The higher heat flux in the used area led to stronger winds and furthe...

In this study, we examine the nonlinear interdependence between the parameters of the solar wind influencing geomagnetic activity (proton density and solar wind dynamic pressure, IMF B z and solar wind dynamic pressure) and geomagnetic indices (AE and SYM-H) during pre-storm, storm and post-storm of intense, major, moderate and minor geomagnetic storms. Nonlinear analytical tools comprising Cross Recurrence Plot (CRP) and Recurrence Rate (RR) was used to capture the features of nonlinear interdependence in the time series data of the solar wind parameters (solar wind dynamic pressure, IMF B z and Proton density) and geomagnetic indices (AE and SYM-H). The Pearson correlation coefficient was also used to reveal the features of linear dependence between the parameters of the solar wind during the different categories of geomagnetic storms. Our result shows that during the storm, the CRPs of the solar wind parameters investigated pictured a strong deterministic structure of CRP which is an indication of strong interdependence. In particular, the results of our analysis showed that the solar wind dynamic pressure and proton density depicted very strong interdependence features. On the other hand, during pre-storm and post-storm, the CRP of solar wind dynamic pressure in relation to IMF B z and proton density pictured a rare deterministic structure signifying weak interdependence. Furthermore, the values of RR were very high (an indication of strong interdependence between the parameters of the solar wind) during the storm while at pre-storm and post-storm, the values of RR declined significantly in most of the periods which further strengthened the evidence of weak interdependence in the parameters of solar wind. The CRP and RR of the geomagnetic indices (AE and SYM-H) reveals no significant difference between pre-storm, storm and post-storm of the different categories of geomagnetic storms. However, strong interdependence between the geomagnetic indices were observed in most of the periods investigated. Finally, the Pearson correlation coefficient reveals high values of linear dependence between the solar wind parameters without any significant difference between pre-storm, storm and post-storm periods during intense, major, moderate and minor geomagnetic storms.

This work is addressing the decision making process involved in the selection of the most suited air q uality model to assess the impact of a cement plant located within a complex terrain domai n in Northern East of Italy. The overall objective is the description and analys is of operational issues arising from the case stud y which are among others: complexity of problem setting, assumptions and range of model app lic bility (pollutant types, spatial and temporal s cales, orography description, wind calm treatment) and the input data availability. The use of a specific model and its setting up is always a trade off between consistency and accuracy of results. Two air quality models (CALPUF F vs ADMS-Urban) were used to simulate emissions fr om the kiln of a cement plant over a complex orography domain (6 Km x 6 Km). Both models were run under different configurations and sensitivity analysis of results was performed. On strict terms this ‘field testing’ was not a comparison of mode...

The study of changes in river discharge is important for the development of effi cient water resource management systems, as well as for the development and validation of climate change impact models. The discharge regime of rivers and their long-term changes in Latvia were investigated. Four major types of river discharge regimes, which depend on climatic and physico-geographic factors, were characterized. These factors are linked to the changes observed in river discharge. Periodic oscillations of discharge intensity, and low-and high-water fl ow years are common for the major rivers in Latvia. A main frequency of about 20 and 13 years was estimated for the studied rivers.

The intensity of soil erosion to occur in a region depends on multiple factors including climatic conditions, elevation, terrain, soil type, and land use. Among these factors, land use is one of the particular importance as it reflects the outsized role of humans in the exacerbation of erosion condition. This study aimed to investigate the effects of land use changes on soil erosion in Qaresu watershed, using Remote Sensing (RS) and Geographical Information System (GIS) techniques, a watershed with an area of 4370.8 km 2 located in the center of Ardabil province, northwest of Iran. For this purpose, the 1985 and 2015 Landsat images captured by TM and OLI-TIRS sensors were used to develop the land use maps of the watershed area using the maximum likelihood method. The erosion zoning maps were then developed by integrating the maps of land use, slope, lithology, distance from roads, distance from streams, precipitation, and soil using the Weighted Linear Combination (WLC) method after an AHP-based weighting stage. The results showed that in the 30-year period from 1985 to 2015, the region has experienced a decrease in the area of forest, dry farming, and rangeland land uses and an increase in the area of land uses defined as urban, barren, irrigated farming, and water cover. In total, dry farming and rangeland were the largest land-uses in the studied area. According to the developed erosion zoning maps, in 1985, 14.4% and 36.84%, and in 2015, 15.64% and 32.3% of the studied area belonged to high and very high risk zones in terms of erosion potential, respectively. In defined two periods, high risk and very high risk zones were mostly positioned over dry and irrigated farmlands.

Due to the spatial variations of the strong ground motions and Near-Field (N-F) effects, significant and unexpected damages have been observed in long-span bridges during past earthquakes. One of the outstanding characteristics of N-F motions is the forward directivity effect seen as a single, intense, long period pulse at the beginning of velocity records in the fault-normal direction. To better understand the effect of this pulse and the wave passage effect of spatially correlated motions on the seismic response of long-span bridges in comparison with these bridges' response to the far-field earthquakes, a comprehensive case study has been done in three parts on the finite element model of a long-span bridge: 1) Uniform excitations of the model bridge with forward directivity pulses and the original records; 2) Asynchronous excitations with different shear wave velocities for impulsive part of the inputs; and 3) Comparison of the wave passage effect of two sets of near-field and far-field strong ground motions (SGMs) on the seismic response of the model bridge. The results show that the wave passage effect of forward directivity N-F pulses can have significant influence on the bridge nonlinear response, and it becomes more evident in the soft soils causing severe seismic demands. Even in the case of rock sites, ignoring this effect can result in under-designed piers. Besides, comparison of the near-field and far-field SGM excitations effect on the bridge response indicates that although in uniform excitations both sets cause approximately the same displacement response values, in the case of asynchronous inputs, the N-F records can produce larger ductility demands.

At an urban site in Kenitra, Morocco, two aerosol size fractions (PM2.5 and PM10) were sampled for four seasons to characterize the seasonal trends of particulate (PM) and carbonaceous (BC) aerosols. An in-depth statistical analysis of the lag-effects of meteorology on collected data was investigated using uni- and multivariate linear regression analyses. The results revealed significant seasonal trends for PM10, PM2.5, and BC. PM concentrations showed the maximum values in autumn (61.4 ± 24.5 µg/m3 for PM10 and 21.2 ± 8.2 µg/m3 for PM2.5), while the minimum was observed in winter (40.2 ± 17.1 µg/m3) for PM10 and in summer (14.3 ± 3.3 µg/m3) for PM2.5. High BC concentrations were recorded in summer (6.3 ± 4.2 μg/m3, on average). The relative humidity 1–2 days earlier showed a higher negative correlation with the PM concentrations (except in winter), and the temperature 1–3 days earlier showed a negative correlation with the PM2.5 in winter and summer and a positive one with the PM10...

River water bodies are being altered due to hydromorphological and chemical pressures. An integrated approach in the assessment of water quality was outlined more as a result of the EU water directives, especially the Water Framework Directive (WFD), which requires the development and harmonization of monitoring and assessment of water quality for all surface water bodies. As WFD addresses water quality in terms of &quot;ecological status&quot; respectively &quot;ecological potential&quot;, the paper aims to discuss the analysis and the assessment of a &quot;heavily modified river water body&quot; in terms of hydromorphological, physico-chemical and biological elements. The analyzed waterbody is in the same time the whole Hartibaciu River (110 km length) located within the central part of Romania. The study is based on monitoring data provided by the National Administration “Apele Romane” – The Olt River Basin Authority for three monitoring sections (one being a reference site). The...

An analysis has been carried out on the effects of variable viscosity on the problem of Magnetohydrodynamic fluid flow past an infinite continuous moving sheet embedded in porous media. The fluid viscosity is assumed to vary as an inverse linear function of temperature. The x -axis runs along the permeable continuous moving surface in the direction of the motion and the y -axis is perpendicular to it. The magnetic field is applied along the y axis. The governing equations have been reduced to the coupled non linear partial differential equations. The system of transformed non linear partial differential equations is solved numerically using the finite difference method. The effects of the various parameters on the flow are analyzed and discussed through graphs.

Symbiotic and asymbiotic nitrogen fixation (SNF and ANF), two forms of biological nitrogen (N) fixation, are the main pathways for external N inputs into natural terrestrial ecosystems. However, the regulatory mechanisms of SNF and ANF, particularly in response to changing environmental conditions, remain poorly understood. Here, we investigated changes in SNF and ANF rates along two altitudinal gradients in two subtropical forests on soils with granite and slate parent materials. Our results revealed distinct patterns for SNF and ANF rates. SNF rates consistently declined with increasing altitude, whereas ANF rates initially increased at lower altitudes but declined at higher altitudes. These contrasting trends were attributed to divergent regulatory mechanisms of SNF and ANF rates. Specifically, the decrease in SNF rates was primarily driven by increased soil N availability and decreased air temperature. However, the drivers of ANF rates shifted from soil properties (e.g., phosphorus, iron, and moisture) at lower altitudes to climatic factors (e.g., air temperature) at higher altitudes. We also observed opposite trends of SNF and ANF between forests on granite and slate, demonstrating that lithology is an important driver of both SNF and ANF. Collectively, our findings highlight the divergent mechanisms regulating SNF and ANF in subtropical forests, which contribute to improving the mechanistic representation of biological N fixation in Earth system models.

Freshwater in the Arctic Ocean plays an important role in the regional ocean circulation, sea ice, and global climate. From salinity observed by a variety of platforms, we are able, for the first time, to estimate a statistically reliable liquid freshwater trend from monthly gridded fields over all upper Arctic Ocean basins. From 1992 to 2012 this trend was 600±300 km3 yr−1. A numerical model agrees very well with the observed freshwater changes. A decrease in salinity made up about two thirds of the freshwater trend and a thickening of the upper layer up to one third. The Arctic Ocean Oscillation index, a measure for the regional wind stress curl, correlated well with our freshwater time series. No clear relation to Arctic Oscillation or Arctic Dipole indices could be found. Following other observational studies, an increased Bering Strait freshwater import to the Arctic Ocean, a decreased Davis Strait export, and enhanced net sea ice melt could have played an important role in the...

After 35 years and 40,000 plus published papers, there is still not one paper in the literature where an atmospheric warming has been measured in an experiment and that any of that warming was attributed to rising levels of carbon dioxide (CO2).

The Earth’s surface temperature is set by atmospheric pressure, auto-compression, convection and solar insolation, not a greenhouse effect.

You will learn that 99% of what you’ve been told about climate change and global warming is wrong. We show that there is no ‘greenhouse effect’ and no such thing as greenhouse gases. We also show that no matter what man tries to do with our CO2 emissions, we cannot control the climate, the global temperature, or even levels of CO2 in the atmosphere.

Trillions of dollars are being wasted on a non-problem.

Atmospheric aerosols and dust have become a challenge for urban air quality. The presented study quantified seasonal spatio-temporal variations of aerosols, tropospheric ozone, and dust over the Middle East (ME) for the year 2012 by using the HTAP emission inventory in the WRF-Chem model. Simulated gaseous pollutants, aerosols and dust were evaluated against satellite measurements and reanalysis datasets. Meteorological parameters, temperature, and wind vector were evaluated against MERRA2. The model showed high spatio-temporal variability in meteorological parameters during summer and low variability in winter. The correlation coefficients for all the parameters are estimated to be 0.92, 0.93, 0.98, and 0.89 for January, April, July, and October respectively, indicating that the WRF-Chem model reproduced results very well. Simulated monthly mean AOD values were maximum in July (1.0–1.5) and minimum in January (0.1–0.4) while April and October were in the range of 0.6–1.0 and 0.3–0....

This paper reports analytical review results on the global and national importance of solar energy as a clean and renewable source of energy. Pre-monsoon and post monsoon seasons have higher mean monthly sunshine duration (about 8 hours/day) than summer (about 5 hours/day) and winter (about 7 hours/day) seasons in Kathmandu. The lowest sunshine duration during summer season is attributed to the effect of monsoonal clouds during that period. Pre-monsoon and monsoon seasons receive solar energy of about 250 W/m2 and 200 W/m2 respectively. The winter season receives the least amount of solar radiation (about 150 W/m2). Results show high prospect of solar energy utilization both in rural and urban areas of Nepal.

The SASS Ozone and Nitrogen Oxides Experiment (SONEX) over the North Atlantic during October/November 1997 offered an excellent opportunity to examine the budget of total reactive nitrogen (NOy) inthe upper troposphere (8 -12 km altitude). The median measured NOy mixing ratio was 425 parts per trillion by volume (pptv). Two different methods were used to measure HNO3: (1) the mist chamber technique and, (2) chemical ionization mass spectrometry. Two merged data sets using these HNO3 measurements were used to calculate NO r by summing the reactive nitrogen species (a combination of measured plus modeled results) and comparing the resultant values to measured NOy (gold catalytic reduction method). Both comparisons showed good agreement in the two quantities (slope > 0.9 and r2 > 0.9). Thus, the total reactive nitrogen budget in the upper troposphere over the North Atlantic can be explained in a general manner as a simple mixture of NOx (NO + NOz), HNO3, and PAN. Median values of NO_/NOy were _0.25, HNO3/NOy =0.35 and PAN/NOy _0.17. Particulate NO 3" and alk-yl nitrates together composed <10% of NOy, while mode/ estimated HNO, averaged 12%.

Accurate representation of aerosol optical properties is essential for the modeling and remote sensing of atmospheric aerosols. Although aerosol optical properties are strongly dependent upon the aerosol size distribution, the use of detailed aerosol microphysics schemes in global atmospheric models is inhibited by associated computational demands. Computationally efficient parameterizations for aerosol size are needed. In this study, airborne measurements over the United States (DISCOVER-AQ) and South Korea (KORUS-AQ) are interpreted with a global chemical transport model (GEOS-Chem) to investigate the variation in aerosol size when organic matter (OM) and sulfate-nitrate-ammonium (SNA) are the dominant aerosol components. The airborne measurements exhibit a strong correlation (r = 0.83) between dry aerosol size and the sum of OM and SNA mass concentration (M SNAOM ). A global microphysical simulation (GEOS-Chem-TOMAS) indicates that M SNAOM and the ratio between the two components (OM/SNA) are the major indicators for SNA and OM dry aerosol size. A parameterization of the dry effective radius (R eff ) for SNA and OM aerosol is designed to represent the airborne measurements (R 2 = 0.74; slope = 1.00) and the GEOS-Chem-TOMAS simulation (R 2 = 0.72; slope = 0.81). When applied in the GEOS-Chem high-performance model, this parameterization improves the agreement between the simulated aerosol optical depth (AOD) and the ground-measured AOD from the Aerosol Robotic Network (AERONET; R 2 from 0.68 to 0.73 and slope from 0.75 to 0.96). Thus, this parameterization offers a computationally efficient method to represent aerosol size dynamically.

Improvements in air quality and Earth's climate predictions require improvements of the aerosol speciation in chemical transport models, using observational constraints. Aerosol speciation (e.g., organic aerosols, black carbon, sulfate, nitrate, ammonium, dust or sea salt) is typically determined using in situ instrumentation. Continuous, routine aerosol composition measurements from ground-based networks are not uniformly widespread over the globe. Satellites, on the other hand, can provide a maximum coverage of the horizontal and vertical atmosphere but observe aerosol optical properties (and not aerosol speciation) based on remote sensing instrumentation. Combinations of satellite-derived aerosol optical properties can inform on air mass aerosol types (AMTs). However, these AMTs are subjectively defined, might often be misclassified and are hard to relate to the critical parameters that need to be refined in models. In this paper, we derive AMTs that are more directly related to sources and hence to speciation. They are defined, characterized and derived using simultaneous in situ gas-phase, chemical and optical instruments on the same aircraft during the Study of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC 4 RS, an airborne field campaign carried out over the US during the summer of 2013). We find distinct optical signatures for AMTs such as biomass burning (from agricultural or wildfires), biogenic and polluted dust. We find that all four AMTs, studied when prescribed using mostly airborne in situ gas measurements, can be successfully extracted from a few combinations of airborne in situ aerosol optical properties (e.g., extinction Ångström exponent, absorption Ångström exponent and real refractive index). However, we Published by Copernicus Publications on behalf of the European Geosciences Union. 3714 M. S. F. Kacenelenbogen et al.: Bridging aerosol chemistry and physics find that the optically based classifications for biomass burning from agricultural fires and polluted dust include a large percentage of misclassifications that limit the usefulness of results related to those classes. The technique and results presented in this study are suitable to develop a representative, robust and diverse source-based AMT database. This database could then be used for widespread retrievals of AMTs using existing and future remote sensing suborbital instruments/networks. Ultimately, it has the potential to provide a much broader observational aerosol dataset to evaluate chemical transport and air quality models than is currently available by direct in situ measurements. This study illustrates how essential it is to explore existing airborne datasets to bridge chemical and optical signatures of different AMTs, before the implementation of future spaceborne missions (e.g., the next generation of Earth Observing System (EOS) satellites addressing Aerosols, Cloud, Convection and Precipitation (ACCP) designated observables).

to dust events, which can be attributed to the sparsely populated nature of the region. Furthermore, seasonal analysis reveals that dust events are prevalent during the Summer months followed by Spring. These results are consistent with previous traditional studies that did not use social media of dust occurrences in the U.S., and Flickr-identified images of dust events show substantial co-occurrence with regions of NWS dust warnings. This paper highlights the potential of using crowdsourced data for the often overlooked field of dust monitoring that has substantial health and economic impacts.

Very rarely, the atmosphere produces a natural experiment that, if captured, has the potential to lend insight into the fundamentals of atmospheric behavior. During the North American solar eclipse on 8 April 2024, a prescribed fire on the grounds of Fort Benning produced a smoky haze in Columbus, Georgia, USA. This haze covered the Columbus State University main campus and the nearby Columbus Airport (KCSG) leading up to and during the peak of the eclipse. Automated Surface Observing Station (ASOS) and Georgia Weather Network observations were examined for the event. At the time of temperature minimum, the temperature depression at KCSG was 0.5 • C greater than at nearby ASOS stations. An "eclipse wind" was observed at KCSG but not at the nearby ASOS stations. Based on observations of steady-state air and dewpoint temperatures, together with rapid fluctuations in visibility, we propose the Subcritical Aerosol-Moisture Feedback (SAMF) mechanism, in which subtle feedbacks among particle growth, relative humidity, and scattering of radiation by aerosol-laden air may maintain steady-state thermodynamic conditions. This case study offers a unique opportunity to examine aerosol behavior under transient radiative forcing, suggesting insights into how a smoky environment enhances thermal buffering and stabilizes the boundary-layer response under rare conditions.

Riverine flooding is associated with not only displacement of people but also loss of property and lives in the lower course of rivers. However, there is a dearth of literature on land use and land cover within flood risk zones and safe zones within the Western Region in Kenya. Using Landsat satellite images and household surveys, this study aimed at mapping land use and land cover within flood risk and safe zones in Budalangi sub-county, Kenya. A sample size of 162 household heads was selected using stratified random sampling. Flood stage scenarios were hypothesized, and overlay analysis was done to determine the locations for evacuation and land use at risk. Descriptive data analysis was adopted to analyze data from respondents. Analyzed Landsat satellite images reveal that 39.1 % (76.2 km²) of the study area were flood risk zones, while 60.9 % (118.8 km²) were safe zones. Ninety percent (90 %, 68.6 km²) of the flood risk zones were located at altitudes less than 1144 m above sea level (a.s.l) while safe zones were located in areas with more than 1144 m a.s.l. Within the flood risk zones, 57.0 % (39.1 km²) was covered with papyrus vegetation, 19.2 % (13.2 km²) with riverine vegetation, 18.4 % (12.6 km²) with farmland, and 5.4 % (3.7 km²) with buildings or bare land. Ninety percent (90 %) of the safe regions were found within learning institutions, market centres and administrative centres. Majority of the respondents (n = 157, 96.9 %) had experienced flooding on their farmlands and some of them (n = 125, 79.6 %) indicated that floods had destroyed their crops. The flooding that occurred frequently within the study area during high rain season was mainly mitigated through terracing and use of canals. Current study concludes that flood risk zones were covered by natural vegetation while safe zones were occupied by human settlement. This study suggests that residents in flood prone areas should avoid residing within flood risk zones during rainy seasons.
Key words: Floods, Flood risk, Fluvial/Riverine Flooding, Safe zones, Budalangi

Laboratory experiments were carried out in a vertical wind tunnel to study the retention of different atmospheric trace gases during riming. In the experiments, the rimed ice particles floated in a laminar air stream carrying a cloud of supercooled droplets with radii between 10 and 20 µm. Ice particles, dendritic ice crystals, and snow flakes with diameters between 6 mm and 1.5 cm were allowed to rime at temperatures between -5 and -12 • C where riming mainly proceeds in the atmosphere and with cloud liquid water contents between 1 and 1.5 g m -3 which are values typically found in atmospheric mixed-phase clouds. Three trace species were investigated, nitric and hydrochloric acid, and hydrogen peroxide. They were present in the supercooled liquid droplets in concentrations from 1 to 120 ppmv, i.e. similar to the concentrations measured in cloud drops. The chemical analyses of the rimed ice particles allow one to determine the trace species concentration in the ice phase. Together with the known liquid phase concentration the retention coefficients were calculated in terms of the amount of the species which remained in the ice phase after freezing. It was found that the highly soluble trace gases, nitric and hydrochloric acid, were retained nearly completely (98.6±8 % and 99.7±9 %, respectively) while for hydrogen peroxide a retention of 64.3±11 % was determined. No influence of the riming temperature on the retention was found which can be explained by the fact that in the observed range of temperature and liquid water content, riming proceeded in the dry growth regime.

Heat shock proteins (Hsp) aid in protein folding and also to combat stress in all cellular organisms. HspB1 is a member of the small HSP family that has a significant role in thermo-tolerance. In this study, we aimed to determine the relationship (if any) between age at sexual maturity of layer poultry (Rhode Island Red and Punjab Red) and HspB1 expression both at mRNA and protein levels under heat stress. The mRNA expression of hspB1 was checked by real-time PCR. Delay in sexual maturity of the birds was found to be directly associated with the hspB1 mRNA expression in both the bird varieties under heat stress. No significant regression (association) of hspB1 mRNA expression with age at sexual maturity was observed in case of control, nonheat stressed birds. The serum levels of HspB1 were measured by indirect ELISA, using recombinant HspB1 that was expressed using pET-32b(+) vector in BL21(DE3) cells. Serum HspB1 concentration increased significantly (p ≤ 0.001) in heat-stressed birds as compared with control ones. A significant association was found between the increase in serum HspB1 concentration and delay in sexual maturity of all the birds under heat stress while no such association was found in control birds. In conclusion, HspB1 mRNA and protein expression were found to be associated with age at sexual maturity in Punjab Red and RIR layers under heat stress.