scholarly journals BrO/SO<sub>2</sub> molar ratios from scanning DOAS measurements in the NOVAC network

2013 ◽  
Vol 5 (2) ◽  
pp. 1845-1870 ◽  
Author(s):  
P. Lübcke ◽  
N. Bobrowski ◽  
S. Arellano ◽  
B. Galle ◽  
G. Garzón ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Optical Absorption Spectroscopy ◽  
Short Term ◽  
Dynamic Changes ◽  
Volcanic System ◽  
Molar Ratios ◽  
Remote Sensing Technique ◽  
Field Campaigns ◽  
Term Field

Abstract. The molar ratio of BrO to SO2 is, like other halogen/sulphur ratios, a~possible precursor for dynamic changes in the shallow part of a volcanic system. While the predictive significance of the BrO/SO2 ratio has not been well constrained yet, it has the major advantage that this ratio can be readily measured using the remote-sensing technique Differential Optical Absorption Spectroscopy (DOAS) in the UV. While BrO/SO2 ratios have been measured during several short-term field campaigns this article presents an algorithm that can be used to obtain long-term time series of BrO/SO2 ratios from the scanning DOAS instruments of the Network for Observation of Volcanic and Atmospheric Change (NOVAC) or comparable networks. Parameters of the DOAS retrieval of both trace gases are given and the influence of co-adding spectra on the retrieval error will be investigated. Difficulties in the evaluation of spectroscopic data from monitoring instruments in volcanic environments and possible solutions are discussed. The new algorithm is demonstrated by evaluating data from the NOVAC scanning DOAS systems at Nevado del Ruiz, Colombia encompassing almost four years of measurements between November 2009 and end of June 2013. This dataset shows variations of the BrO/SO2 ratio several weeks prior to the eruption on 30 June 2012.

scholarly journals BrO/SO<sub>2</sub> molar ratios from scanning DOAS measurements in the NOVAC network

Solid Earth ◽  
2014 ◽  
Vol 5 (1) ◽  
pp. 409-424 ◽  
Author(s):  
P. Lübcke ◽  
N. Bobrowski ◽  
S. Arellano ◽  
B. Galle ◽  
G. Garzón ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Optical Absorption Spectroscopy ◽  
Dynamic Changes ◽  
Data Set ◽  
Volcanic System ◽  
Molar Ratios ◽  
Remote Sensing Technique ◽  
Field Campaigns ◽  
Term Field

Abstract. The molar ratio of BrO to SO2 is, like other halogen/sulfur ratios, a possible precursor for dynamic changes in the shallow part of a volcanic system. While the predictive significance of the BrO/SO2 ratio has not been well constrained yet, it has the major advantage that this ratio can be readily measured using the remote-sensing technique differential optical absorption spectroscopy (DOAS) in the UV. While BrO/SO2 ratios have been measured during several short-term field campaigns, this article presents an algorithm that can be used to obtain long-term time series of BrO/SO2 ratios from the scanning DOAS instruments of the Network for Observation of Volcanic and Atmospheric Change (NOVAC) or comparable networks. Parameters of the DOAS retrieval of both trace gases are given. The influence of co-adding spectra on the retrieval error and influences of radiative transfer will be investigated. Difficulties in the evaluation of spectroscopic data from monitoring instruments in volcanic environments and possible solutions are discussed. The new algorithm is demonstrated by evaluating data from the NOVAC scanning DOAS systems at Nevado del Ruiz, Colombia, encompassing almost 4 years of measurements between November 2009 and end of June 2013. This data set shows variations of the BrO/SO2 ratio several weeks prior to the eruption on 30 June 2012.

A global perspective on Bromine monoxide composition in volcanic plumes derived from three years of S5-P/TROPOMI data

2021 ◽  
Author(s):  
Simon Warnach ◽  
Holger Sihler ◽  
Christian Borger ◽  
Nicole Bobrowski ◽  
Stefan Schmitt ◽  
...  
Keyword(s):  
Global Perspective ◽  
Coefficient Of Determination ◽  
Optical Absorption Spectroscopy ◽  
Polar Regions ◽  
Volcanic Gas ◽  
Volcanic Plumes ◽  
Molar Ratios ◽  
Volcanic Events ◽  
Global Coverage

&lt;p&gt;Bromine monoxide (BrO) is a halogen radical capable of influencing atmospheric chemical processes, in particular the abundance of ozone, e. g. in the troposphere of polar regions, the stratosphere as well as in volcanic plumes. Furthermore, the molar bromine to sulphur ratio in volcanic gas emissions is a proxy for the magmatic composition of a volcano and potentially an eruption forecast parameter.&lt;/p&gt;&lt;p&gt;The high spatial resolution of the S5-P/TROPOMI instrument (up to 3.5x5.5km&lt;sup&gt;2&lt;/sup&gt;) and its daily global coverage offer the potential to detect BrO even during minor eruptions and also to determine BrO/SO&lt;sub&gt;2&lt;/sub&gt; ratios during continuous passive degassing.&lt;/p&gt;&lt;p&gt;Here, we present a global overview of BrO/SO&lt;sub&gt;2&lt;/sub&gt; molar ratios in volcanic plumes derived from a systematic long-term investigation of three years of TROPOMI data.&lt;/p&gt;&lt;p&gt;We retrieved column densities of BrO and SO&lt;sub&gt;2&lt;/sub&gt; using Differential Optical Absorption Spectroscopy (DOAS) and calculated mean BrOSO&lt;sub&gt;2&lt;/sub&gt; molar ratios for each volcano. As expected, the calculated BrO/SO&lt;sub&gt;2&lt;/sub&gt; molar ratios differ strongly between different volcanoes ranging from several 10&lt;sup&gt;-5&lt;/sup&gt; up to several 10&lt;sup&gt;-4&lt;/sup&gt;. In our study of three years of S5P/TROPOMI data we successfully recorded elevated BrO column densities for more than 100 volcanic events and were able to derive meaningful (coefficient of determination, R&lt;sup&gt;2&lt;/sup&gt; exceeding 0.5) BrO/SO&lt;sub&gt;2&lt;/sub&gt; ratios for multiple volcanoes.&lt;/p&gt;

Dynamic changes in HLA-DR expression during short-term and long-term ibrutinib treatment in patients with chronic lymphocytic leukemia

2018 ◽  
Vol 72 ◽  
pp. 113-119 ◽  
Author(s):  
Gayane Manukyan ◽  
Peter Turcsanyi ◽  
Zuzana Mikulkova ◽  
Gabriela Gabcova ◽  
Renata Urbanova ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Lymphocytic Leukemia ◽  
Short Term ◽  
Dynamic Changes ◽  
Hla Dr

Study on Characteristics of Water Waves in Bohai Sea Using SWAN Model

2014 ◽  
Vol 522-524 ◽  
pp. 983-989
Author(s):  
Dao Sheng Wang ◽  
Xiang Cui Lv ◽  
De Kui Yuan
Keyword(s):  
Wave Height ◽  
Water Waves ◽  
Bohai Sea ◽  
Measured Data ◽  
Wave Direction ◽  
Short Term ◽  
The Bohai Sea ◽  
Good Agreement ◽  
Term Field

The SWAN (Simulating WAves Nearshore) model was applied to study the characteristics of water waves in the Bohai Sea. The model was calibrated against both short-term and long-term field measured data from six different stations in the Bohai Sea and the computational results are in good agreement with the measured data. Then the wave process during 1999 to 2009 in the Bohai Sea was simulated using the calibrated model. The wave characteristics such as significant wave height, average period, dominant wave direction and their seasonal variations were analyzed based on the simulated results. The distributions of wave height and wave period are similar to those of the previous studies, but the wave height is slightly smaller than that given by other researchers.

scholarly journals Long-term field-realistic exposure to a next-generation pesticide, flupyradifurone, impairs honey bee behaviour and survival

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Simone Tosi ◽  
James C. Nieh ◽  
Annely Brandt ◽  
Monica Colli ◽  
Julie Fourrier ◽  
...  
Keyword(s):  
Honey Bees ◽  
Global Scale ◽  
Risk Assessments ◽  
Ring Test ◽  
Emerging Contaminant ◽  
Short Term ◽  
Insect Pollinators ◽  
Impact Of Pesticides ◽  
Term Field

AbstractThe assessment of pesticide risks to insect pollinators have typically focused on short-term, lethal impacts. The environmental ramifications of many of the world’s most commonly employed pesticides, such as those exhibiting systemic properties that can result in long-lasting exposure to insects, may thus be severely underestimated. Here, seven laboratories from Europe and North America performed a standardised experiment (a ring-test) to study the long-term lethal and sublethal impacts of the relatively recently approved ‘bee safe’ butenolide pesticide flupyradifurone (FPF, active ingredient in Sivanto®) on honey bees. The emerging contaminant, FPF, impaired bee survival and behaviour at field-realistic doses (down to 11 ng/bee/day, corresponding to 400 µg/kg) that were up to 101-fold lower than those reported by risk assessments (1110 ng/bee/day), despite an absence of time-reinforced toxicity. Our findings raise concerns about the chronic impact of pesticides on pollinators at a global scale and support a novel methodology for a refined risk assessment.

scholarly journals Long-term field experiment on the impacts of the neonicotinoid dinotefuran and the organophosphate fenitrothion on a honeybee colony

2015 ◽  
Author(s):  
Toshiro Yamada ◽  
Yasuhiro Yamada ◽  
Kazuko Yamada
Keyword(s):  
Field Experiment ◽  
Lethal Dose ◽  
Short Term ◽  
Long Period ◽  
Sugar Syrup ◽  
The World ◽  
Long Term Experiments ◽  
Honeybee Colony ◽  
Term Field

Neonicotinoides are persistent and highly toxic pesticides that have become popular instead of organophosphates, being suspected to be a trigger of massive disappearance of bees that raises concern in the world. The evaluation of the long-term influence for a whole colony in the natural environment is, however, not established yet. In this paper, we conducted a long-term field experiment and found different impacts on honeybee colonies (Apis mellifera) in an apiary between the neonicotinoid dinotefuran and the organophosphate fenitrothion even though whose concentrations in sugar syrup provided for bees were adjusted to have nearly equal short-term effects on a honeybee based on the median lethal dose (LD50) as well as the insecticidal activity to exterminate stinkbugs. The colony with administration of dinotefran (dinotefuran colony) became extinct in 26 days, while the colony with administration of fenitrothion (fenitrothion colony) survived the administration for the same period. Furthermore, the fenitrothion colony succeeded to be alive for more than 293 days after administration, and also succeeded an overwintering, which indicates that colonies exposed to fenitrothion can recover after the exposure. Meanwhile, the dinotefuran colony became extinct even though the intake of dinotefuran was estimated to be comparable with that of fenitrothion in terms of the LD50 of a honeybee. Moreover, the colonies in our previous long-term experiments where dinotefuran with higher concentration were administered only for first few days (Yamada et al., 2012) became extinct in 104 days and 162 days, respectively. From these results, we speculate that colonies exposed to dinotefuran hardly recover from the damage because dinotefuran is much more persistent than fenitrothion and toxic foods stored in cells can affect a colony in a long period.

scholarly journals Hyper-Nutrient Enrichment Status in the Sabalan Lake, Iran

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2874
Author(s):  
Roohollah Noori ◽  
Elmira Ansari ◽  
Yong-Wook Jeong ◽  
Saber Aradpour ◽  
Mohsen Maghrebi ◽  
...  
Keyword(s):  
Nutrient Enrichment ◽  
Management Practices ◽  
Storage Capacity ◽  
Limiting Factors ◽  
Molar Ratio ◽  
Anthropogenic Factors ◽  
Short Term ◽  
Reservoir Water ◽  
P Deficiency

Lakes/reservoirs are rapidly deteriorating from cultural eutrophication due to anthropogenic factors. In this study, we aimed to (1) explore nutrient levels in the Sabalan dam reservoir (SDR) of northwest Iran, (2) determine the reservoir water fertility using the total phosphorus (TP)based and total nitrogen (TN)based Carlson trophic state indices, and (3) specify primary limiting factors for the reservoir eutrophication. Our field observations showed a state of hyper-nutrient enrichment in the SDR. The highest variation of TN in the reservoir water column happened when the reservoir was severely stratified (in August) while the highest variation of TP took place when the thermocline was attenuated with the deepening of the epilimnion (in October). Both TP and TN based trophic indicators classified the SDR as a hypereutrophic lake. TN:TP molar ratio averaged at the epilimnion indicated a P–deficiency in the reservoir during warm months whilst it suggested a co–deficiency of P and N in cold months. Given the hyper-nutrient enrichment state in the reservoir, other drivers such as water residence time (WRT) can also act as the main contributor of eutrophication in the SDR. We found that WRT in the SDR varied from hundreds to thousands of days, which was much longer than that of other reservoirs/lakes with the same and even much greater storage capacity. Therefore, both hyper-nutrient enrichment and WRT mainly controlled eutrophication in the reservoir. Given time consuming and expensive management practices for reducing nutrients in the watershed, changes in the SDR operation are suggested to somewhat recover its hypereutrophic state in the short-term. However, strategic long-term recovery plans are required to reduce the transition of nutrients from the watershed to the SDR.

scholarly journals On the importance of time scales when studying adaptive evolution

2018 ◽  
Author(s):  
Charles Perrier ◽  
Anne Charmantier
Keyword(s):  
Time Scales ◽  
Quantitative Traits ◽  
Field Studies ◽  
Data Series ◽  
Wild Populations ◽  
Short Term ◽  
Trait Variation ◽  
Bill Length ◽  
Term Field

AbstractLong-term field studies coupled with quantitative genomics offer a powerful means to understand the genetic bases underlying quantitative traits and their evolutionary changes. However, analyzing and interpreting the time scales at which adaptive evolution occurs is challenging. First, while evolution is predictable in the short term, with strikingly rapid phenotypic changes in data series, it remains unpredictable in the long term. Second, while the temporal dynamics of some loci with large effect on phenotypic variation and fitness have been characterized, this task can be complicated in cases of highly polygenic trait architecture implicating numerous small effect size loci, or when statistical tests are sensitive to the heterogeneity of some key characteristics of the genome, like recombination rate variations. After introducing these aforementioned challenges, we discuss a recent investigation of the genomic architecture and spatio-temporal variation in great tit bill length, which was related to the recent use of bird feeders. We discuss how this case study illustrates the importance of considering different temporal scales and evolutionary mechanisms both while analyzing trait temporal trends and when searching for and interpreting the signals of putative genomic footprints of selection. More generally this commentary discusses interesting challenges for unraveling the time scale at which adaptive traits evolve and their genomic bases.Impact summaryAn important goal in evolutionary biology is to understand how individual traits evolve, leading to fascinating variations in time and space. Long-term field studies have been crucial in trying to understand the timing, extent, and ecological determinants of such trait variation in wild populations. In this context, recent genomic tools can be used to look for the genetic bases underlying such trait variation and can provide clues on the nature and timing of their evolution. However, the analysis and the interpretation of the time scales at which evolution occurs remain challenging. First, analyzing long-term data series can be tricky; short-term changes are highly predictable whereas long-term evolution is much less predictable. A second difficult task is to study the architecture of complex quantitative traits and to decipher the timing and roles of the several genomic mechanisms involved in their evolution. This commentary introduces these challenges and discusses a recent investigation of the nature and timing of ecological and genomic factors responsible for variation in great tit bill length. Overall, we raise cautionary warnings regarding several conceptual and technical features and limitations when coupling analyses of long-term and genomic data to study trait evolution in wild populations.

Tests for phosphates from Rum Jungle, Northern Territory

1970 ◽  
Vol 10 (46) ◽  
pp. 592 ◽  
Author(s):  
MJ Fisher ◽  
MJT Norman
Keyword(s):  
Rock Phosphate ◽  
Field Experiments ◽  
Northern Territory ◽  
Residual Effects ◽  
Short Term ◽  
Christmas Island ◽  
Second Year ◽  
Term Response ◽  
Term Field

Phosphate-rich rock from Rum Jungle, N.T., was tested as fertilizer against Christmas Island rock phosphate dust (CIRPD) and superphosphate in two pot and three field experiments. The Rum Jungle material had little short-term value as fertilizer, but the long-term residual effects were about 60 per cent of those of CIRPD. Calcining at 450�C gave a marked improvement in short-term response in pots, but had little effect in a long-term field experiment. Pelletting the Rum Jungle material with sulphur and Thiobacillus ('biosuper') increased its effectiveness in the field at the end of the second year to the equivalent of that of superphosphate.

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