scholarly journals Five-year flask measurements of long-lived trace gases in India

2015 ◽  
Vol 15 (5) ◽  
pp. 7171-7238 ◽  
Author(s):  
X. Lin ◽  
N. K. Indira ◽  
M. Ramonet ◽  
M. Delmotte ◽  
P. Ciais ◽  
...  
Keyword(s):  
Indian Subcontinent ◽  
Trace Gases ◽  
Temporal Variations ◽  
Seasonal Cycles ◽  
Synoptic Scale ◽  
Observation Network ◽  
Annual Means ◽  
Atmospheric Concentrations ◽  
Regional Fluxes

Abstract. With the rapid growth in population and economic development, emissions of greenhouse gases (GHGs) from the Indian subcontinent have sharply increased during recent decades. However, evaluation of regional fluxes of GHGs and characterization of their spatial and temporal variations by atmospheric inversions remain uncertain due to a sparse regional atmospheric observation network. As a result of Indo-French collaboration, three new atmospheric stations were established in India at Hanle (HLE), Pondicherry (PON) and Port Blair (PBL), with the objective of monitoring the atmospheric concentrations of GHGs and other trace gases. Here we present the results of five-year measurements (2007–2011) of CO2, CH4, N2O, SF6, CO, and H2 from regular flask sampling at these three stations. For each species, annual means, seasonal cycles and gradients between stations were calculated and related to variations in the natural GHG fluxes, anthropogenic emissions, and the monsoon circulations. Covariances between species at the synoptic scale were analyzed to investigate the dominant source(s) of emissions. The flask measurements of various trace gases at the three stations show potential to constrain the inversions of fluxes over Southern and Northeastern India. However, this network of ground stations needs further extension to other parts of India to allow a better understanding of, and constraints on the GHG budgets at regional and continental scales.

scholarly journals Long-lived atmospheric trace gases measurements in flask samples from three stations in India

2015 ◽  
Vol 15 (17) ◽  
pp. 9819-9849 ◽  
Author(s):  
X. Lin ◽  
N. K. Indira ◽  
M. Ramonet ◽  
M. Delmotte ◽  
P. Ciais ◽  
...  
Keyword(s):  
Indian Subcontinent ◽  
Trace Gases ◽  
Temporal Variations ◽  
Seasonal Cycles ◽  
Synoptic Scale ◽  
Observation Network ◽  
Annual Means ◽  
Atmospheric Concentrations ◽  
Regional Fluxes

Abstract. With the rapid growth in population and economic development, emissions of greenhouse gases (GHGs) from the Indian subcontinent have sharply increased during recent decades. However, evaluation of regional fluxes of GHGs and characterization of their spatial and temporal variations by atmospheric inversions remain uncertain due to a sparse regional atmospheric observation network. As a result of an Indo-French collaboration, three new atmospheric stations were established in India at Hanle (HLE), Pondicherry (PON) and Port Blair (PBL), with the objective of monitoring the atmospheric concentrations of GHGs and other trace gases. Here we present the results of the measurements of CO2, CH4, N2O, SF6, CO, and H2 from regular flask sampling at these three stations over the period 2007–2011. For each species, annual means, seasonal cycles and gradients between stations were calculated and related to variations in natural GHG fluxes, anthropogenic emissions, and monsoon circulations. Covariances between species at the synoptic scale were analyzed to investigate the likely source(s) of emissions. The flask measurements of various trace gases at the three stations have the potential to constrain the inversions of fluxes over southern and northeastern India. However, this network of ground stations needs further extension to other parts of India to better constrain the GHG budgets at regional and continental scales.

scholarly journals Temporal evolution of flow-like landslide hazard for a road infrastructure in the municipality of Nocera Inferiore (southern Italy) under the effect of climate change

2018 ◽  
Vol 18 (11) ◽  
pp. 3019-3035 ◽  
Author(s):  
Marco Uzielli ◽  
Guido Rianna ◽  
Fabio Ciervo ◽  
Paola Mercogliano ◽  
Unni K. Eidsvig
Keyword(s):  
Climate Change ◽  
Southern Italy ◽  
Spatial Location ◽  
Temporal Variations ◽  
Landslide Hazard ◽  
Climate Projections ◽  
Atmospheric Concentration ◽  
Campania Region ◽  
Event Occurrence

Abstract. In recent years, flow-like landslides have extensively affected pyroclastic covers in the Campania region in southern Italy, causing human suffering and conspicuous economic damages. Due to the high criticality of the area, a proper assessment of future variations in event occurrences due to expected climate changes is crucial. The study assesses the temporal variation in flow-like landslide hazard for a section of the A3 “Salerno–Napoli” motorway, which runs across the toe of the Monte Albino relief in the Nocera Inferiore municipality. Hazard is estimated spatially depending on (1) the likelihood of rainfall-induced event occurrence within the study area and (2) the probability that the any specific location in the study area will be affected during the runout. The probability of occurrence of an event is calculated through the application of Bayesian theory. Temporal variations due to climate change are estimated up to the year 2100 through an ensemble of high-resolution climate projections, accounting for current uncertainties in the characterization of variations in rainfall patterns. Reach probability, or defining the probability that a given spatial location is affected by flow-like landslides, is calculated spatially based on a distributed empirical model. The outputs of the study predict substantial increases in occurrence probability over time for two different scenarios of future socioeconomic growth and atmospheric concentration of greenhouse gases.

Isolation and Molecular Characterization of Newcastle Disease Virus in Layers

2021 ◽  
Author(s):  
Smita Bordoloi ◽  
Anju Nayak ◽  
A.P. Singh ◽  
R.V. Singh ◽  
Kajal Jadav ◽  
...  
Keyword(s):  
Newcastle Disease Virus ◽  
Disease Virus ◽  
Newcastle Disease ◽  
Virulent Strain ◽  
Indian Subcontinent ◽  
Economic Losses ◽  
Tissue Samples ◽  
F Gene ◽  
Virulent Newcastle Disease Virus

Background: Newcastle disease (ND) in spite of the availability of vaccines remains a constant threat to poultry producers worldwide. It is prevalent in Indian subcontinent and leads to economic losses. The present study was aimed with isolate and identify virulent Newcastle disease virus (NDV) in layer poultry from field outbreaks.Methods: Total 47 samples consisting of nasal (05), oropharyngeal (13) and cloacal swabs (11) and tissue samples consisting of trachea (07), lungs (06), larynx (05) were collected from layer birds. For isolation of NDV swab and tissue samples were inoculated in 9-11 days old embryonated eggs via allantoic cavity route. After preparing the viral inoculum, 47 suspected samples (29 swab and 18 tissue samples) were inoculated in 141 embryonated eggs to isolate the virus.Result: Out of 47 samples 10 (21.27%) samples were positive for HA activity. All the 10 isolates showing HA activity subjected to Reverse-Transcriptase PCR of F gene and 6 were found positive in RT-PCR for F1 gene. The PCR amplified product showed amplicon at 356 bp and 254 bp positive for F1 and F2 gene, respectively. On basis of F gene, 06 (50%) isolates were considered as virulent Newcastle Disease Virus. One isolate sequence was submitted at NCBI with accession MT890653 On phylogenetic analysis MT890653 designated as Class II/ genotype II/ virulent strain and had the motif 112R-R-R-K-R-F117 at the cleavage site of the fusion protein.

Studying the spatial and seasonal variability of greenhouse gases across West Siberia: large-scale mobile measurement campaigns of 2018-2019

2020 ◽  
Author(s):  
Mikhail Arshinov ◽  
Boris Belan ◽  
Denis Davydov ◽  
Artem Kozlov ◽  
Alexander Fofonov ◽  
...  
Keyword(s):  
Greenhouse Gases ◽  
Large Scale ◽  
Seasonal Pattern ◽  
West Siberia ◽  
Small Scale ◽  
Seasonal Cycles ◽  
Ocean Optics ◽  
Atmospheric Physics ◽  
Mixing Ratios ◽  
Observation Network

<p>The continuous ground-based measurements of greenhouse gases carried out in Siberia in the past two decades allowed the long-term trends, as well as the diurnal and seasonal cycles of CO<sub>2</sub> and CH<sub>4</sub> to be derived for this poorly studied region (Belikov et al., 2019). To date, these in-situ observations are made at the joint Japan-Russia Siberian Tall Tower Inland Observation Network (JR-STATION) consisted of 6 automated stations that should be maintained several times per year. In late October to early November 2018, we have undertaken the first mobile campaign to derive a distribution of CO<sub>2</sub> and CH<sub>4</sub> concentrations at high spatial resolution while traveling to the sites of the above network. For that, we used a commercially available GHG CRDS analyzer (G4301, Picarro Inc., Santa Clara, CA, USA) installed in an off-road vehicle (Arshinov et al., 2019). Over one trip, the instrument were driven over 7000 km throughout the study area.</p><p>In March, June, August, and October 2019 we have performed four more campaigns along the same route. This enabled the seasonal pattern of CO<sub>2</sub> and CH<sub>4</sub> concentrations to be obtained over a huge area of West Siberia between 54.5° and 63.2° north latitude and between 62.3° and 85.0° east longitude, as well as to reveal a large- and small-scale spatial heterogeneity in CH<sub>4</sub> mixing ratios particularly over wetland regions. We plan to continue mobile campaigns to cover interannual variations.</p><p> </p><p>This work was supported by the Ministry of Science and Higher Education of the Russian Federation under State Contract No. 14.616.21.0104 (ID No RFMEFI61618X0104).</p><p>Belikov, D.; Arshinov, M.; Belan, B.; Davydov, D.; Fofonov, A.; Sasakawa, M.; Machida, T. Analysis of the Diurnal, Weekly, and Seasonal Cycles and Annual Trends in Atmospheric CO<sub>2</sub> and CH<sub>4</sub> at Tower Network in Siberia from 2005 to 2016. Atmosphere 2019, 10, 689.</p><p>Arshinov, M.Yu.; Belan B.D.; Davydov D.K.;  Kozlov A.V., Fofonov A.V., and  Arshinova V. Heterogeneity of the spatial distribution of CO<sub>2</sub> and CH<sub>4</sub> concentrations in the atmospheric surface layer over West Siberia: October-November 2018, Proc. SPIE 11208, 25th International Symposium on Atmospheric and Ocean Optics: Atmospheric Physics, 1120831 (18 December 2019);https://doi.org/10.1117/12.2539205</p>

scholarly journals In situ measurement of atmospheric CO<sub>2</sub> at the four WMO/GAW stations in China

2014 ◽  
Vol 14 (5) ◽  
pp. 2541-2554 ◽  
Author(s):  
S. X. Fang ◽  
L. X. Zhou ◽  
P. P. Tans ◽  
P. Ciais ◽  
M. Steinbacher ◽  
...  
Keyword(s):  
Atmospheric Carbon Dioxide ◽  
Co2 Concentration ◽  
Comprehensive Analysis ◽  
Northeastern China ◽  
Seasonal Cycles ◽  
Production Area ◽  
Carbon Dioxide Co2 ◽  
The City

Abstract. Atmospheric carbon dioxide (CO2) mole fractions were continuously measured from January 2009 to December 2011 at four atmospheric observatories in China using cavity ring-down spectroscopy instruments. The stations are Lin'an (LAN), Longfengshan (LFS), Shangdianzi (SDZ), and Waliguan (WLG), which are regional (LAN, LFS, SDZ) or global (WLG) measurement stations of the World Meteorological Organization's Global Atmosphere Watch program (WMO/GAW). LAN is located near the megacity of Shanghai, in China's economically most developed region. LFS is in a forest and rice production area, close to the city of Harbin in northeastern China. SDZ is located 150 km northeast of Beijing. WLG, hosting the longest record of measured CO2 mole fractions in China, is a high-altitude site in northwestern China recording background CO2 concentration. The CO2 growth rates are 3.7 ± 1.2 ppm yr−1 for LAN, 2.7 ± 0.8 ppm yr−1 for LFS, 3.5 ± 1.6 ppm yr−1 for SDZ, and 2.2 ± 0.8 ppm yr−1 (1σ) for WLG during the period of 2009 to 2011. The highest annual mean CO2 mole fraction of 404.2 ± 3.9 ppm was observed at LAN in 2011. A comprehensive analysis of CO2 variations, their diurnal and seasonal cycles as well as the analysis of the influence of local sources on the CO2 mole fractions allows a characterization of the sampling sites and of the key processes driving the CO2 mole fractions. These data form a basis to improve our understanding of atmospheric CO2 variations in China and the underlying fluxes using atmospheric inversion models.

scholarly journals Field characterization of the PM<sub>2.5</sub> Aerosol Chemical Speciation Monitor: insights into the composition, sources, and processes of fine particles in eastern China

2017 ◽  
Vol 17 (23) ◽  
pp. 14501-14517 ◽  
Author(s):  
Yunjiang Zhang ◽  
Lili Tang ◽  
Philip L. Croteau ◽  
Olivier Favez ◽  
Yele Sun ◽  
...  
Keyword(s):  
Chemical Speciation ◽  
Fine Particles ◽  
Eastern China ◽  
Temporal Variations ◽  
Inorganic Aerosols ◽  
Mass Fractions ◽  
Highly Correlated ◽  
First Time

Abstract. A PM2.5-capable aerosol chemical speciation monitor (Q-ACSM) was deployed in urban Nanjing, China, for the first time to measure in situ non-refractory fine particle (NR-PM2.5) composition from 20 October to 19 November 2015, along with parallel measurements of submicron aerosol (PM1) species by a standard Q-ACSM. Our results show that the NR-PM2.5 species (organics, sulfate, nitrate, and ammonium) measured by the PM2.5-Q-ACSM are highly correlated (r2 > 0.9) with those measured by a Sunset Lab OC  /  EC analyzer and a Monitor for AeRosols and GAses (MARGA). The comparisons between the two Q-ACSMs illustrated similar temporal variations in all NR species between PM1 and PM2.5, yet substantial mass fractions of aerosol species were observed in the size range of 1–2.5 µm. On average, NR-PM1−2.5 contributed 53 % of the total NR-PM2.5, with sulfate and secondary organic aerosols (SOAs) being the two largest contributors (26 and 27 %, respectively). Positive matrix factorization of organic aerosol showed similar temporal variations in both primary and secondary OAs between PM1 and PM2.5, although the mass spectra were slightly different due to more thermal decomposition on the capture vaporizer of the PM2.5-Q-ACSM. We observed an enhancement of SOA under high relative humidity conditions, which is associated with simultaneous increases in aerosol pH, gas-phase species (NO2, SO2, and NH3) concentrations and aerosol water content driven by secondary inorganic aerosols. These results likely indicate an enhanced reactive uptake of SOA precursors upon aqueous particles. Therefore, reducing anthropogenic NOx, SO2, and NH3 emissions might not only reduce secondary inorganic aerosols but also the SOA burden during haze episodes in China.

scholarly journals Heart-brain interactions in the MR environment: characterization of the ballistocardiogram in EEG signals collected during simultaneous fMRI

2017 ◽  
Author(s):  
Marco Marino ◽  
Quanying Liu ◽  
Mariangela Del Castello ◽  
Cristiana Corsi ◽  
Nicole Wenderoth ◽  
...  
Keyword(s):  
Temporal Dynamics ◽  
Cardiac Activity ◽  
Principal Component ◽  
Head Rotation ◽  
Temporal Variations ◽  
Single Subject ◽  
Cardiac Events ◽  
Large Variability ◽  
Eeg Recordings

AbstractThe ballistocardiographic (BCG) artifact is linked to cardiac activity and occurs in electroencephalographic (EEG) recordings acquired inside the magnetic resonance (MR) environment. Its variability in terms of amplitude, waveform shape and spatial distribution over subject’s scalp makes its attenuation a challenging task. In this study, we aimed to provide a detailed characterization of the BCG properties, including its temporal dependency on cardiac events and its spatio-temporal dynamics. To this end, we used high-density EEG data acquired during simultaneous functional MR imaging in six healthy volunteers. First, we investigated the relationship between cardiac activity and BCG occurrences in the EEG recordings. We observed large variability in the delay between ECG and subsequent BCG events (ECG-BCG delay) across subjects and non-negligible epoch-by-epoch variations at the single subject level. Also, we found positive correlations between heart rate variability and ECG-BCG delay. The inspection of spatial-temporal variations revealed a prominent non-stationarity of the BCG signal. We identified five main BCG waves, which were common across subjects. Principal component analysis revealed two spatially distinct patterns to explain most of the variance (85% in total). These components are possibly related to head rotation and pulse-driven scalp expansion, respectively. Our results may inspire the development of novel, more effective methods for the removal of the BCG, capable of isolating and attenuating artifact occurrences while preserving true neuronal activity.

scholarly journals Bias corrections of GOSAT SWIR XCO<sub>2</sub> and XCH<sub>4</sub> with TCCON data and their evaluation using aircraft measurement data

2016 ◽  
Author(s):  
M. Inoue ◽  
I. Morino ◽  
O. Uchino ◽  
T. Nakatsuru ◽  
Y. Yoshida ◽  
...  
Keyword(s):  
Measurement Data ◽  
Correction Method ◽  
Temporal Variations ◽  
Department Of Energy ◽  
Total Carbon ◽  
Japan Meteorological Agency ◽  
Aircraft Measurement ◽  
Observation Network ◽  
Systematic Biases ◽  
Aircraft Data

Abstract. We describe a method for removing systematic biases of column-averaged dry air mole fractions of CO2 (XCO2) and CH4 (XCH4) derived from short-wavelength infrared (SWIR) spectra of the Greenhouse gases Observing SATellite (GOSAT). We conduct correlation analyses between the GOSAT biases and simultaneously-retrieved auxiliary parameters. We use these correlations to bias correct the GOSAT data, removing these spurious correlations. Data from Total Carbon Column Observing Network (TCCON) were used as reference values for this regression analysis. To evaluate the effectiveness of this correction method, the uncorrected/corrected GOSAT data were compared to independent XCO2 and XCH4 data derived from aircraft measurements taken for the Comprehensive Observation Network for TRace gases by AIrLiner (CONTRAIL) project, the National Oceanic and Atmospheric Administration (NOAA), the U.S. Department of Energy (DOE), the National Institute for Environmental Studies (NIES), the Japan Meteorological Agency (JMA), the HIAPER Pole- to-Pole observations (HIPPO) program, and the GOSAT validation aircraft observation campaign over Japan. These comparisons demonstrate that the empirically-derived bias correction improves the agreement between GOSAT XCO2/XCH4 and the aircraft data. Finally, we present latitudinal distributions and temporal variations of the derived GOSAT biases.

scholarly journals The imprint of surface fluxes and transport on variations in total column carbon dioxide

2011 ◽  
Vol 8 (4) ◽  
pp. 7475-7524 ◽  
Author(s):  
G. Keppel-Aleks ◽  
P. O. Wennberg ◽  
R. A. Washenfelder ◽  
D. Wunch ◽  
T. Schneider ◽  
...  
Keyword(s):  
Northern Hemisphere ◽  
Large Scale ◽  
Carbon Sink ◽  
Potential Temperature ◽  
Surface Flux ◽  
Growing Season ◽  
Temporal Variations ◽  
Surface Fluxes ◽  
Synoptic Scale ◽  
Meridional Gradient

Abstract. New observations of the vertically integrated CO2 mixing ratio, ⟨CO2⟩, from ground-based remote sensing show that variations in ⟨CO2⟩ are primarily determined by large-scale flux patterns. They therefore provide fundamentally different information than observations made within the boundary layer, which reflect the combined influence of large scale and local fluxes. Observations of both ⟨CO2⟩ and CO2 concentrations in the free troposphere show that large-scale spatial gradients induce synoptic-scale temporal variations in ⟨CO2⟩ in the Northern Hemisphere midlatitudes through horizontal advection. Rather than obscure the signature of surface fluxes on atmospheric CO2, these synoptic-scale variations provide useful information that can be used to reveal the meridional flux distribution. We estimate the meridional gradient in ⟨CO2⟩ from covariations in ⟨CO2⟩ and potential temperature, θ, a dynamical tracer, on synoptic timescales to evaluate surface flux estimates commonly used in carbon cycle models. We find that Carnegie Ames Stanford Approach (CASA) biospheric fluxes underestimate both the ⟨CO2⟩ seasonal cycle amplitude throughout the Northern Hemisphere midlatitudes as well as the meridional gradient during the growing season. Simulations using CASA net ecosystem exchange (NEE) with increased and phase-shifted boreal fluxes better reflect the observations. Our simulations suggest that boreal growing season NEE (between 45–65° N) is underestimated by ~40 % in CASA. We describe the implications for this large seasonal exchange on inference of the net Northern Hemisphere terrestrial carbon sink.

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