scholarly journals A multi-decadal history of biomass burning plume heights identified using aerosol index measurements

2010 ◽  
Vol 10 (14) ◽  
pp. 6461-6469 ◽  
Author(s):  
H. Guan ◽  
R. Esswein ◽  
J. Lopez ◽  
R. Bergstrom ◽  
A. Warnock ◽  
...  
Keyword(s):  
High Altitude ◽  
Biomass Burning ◽  
Northeast Asia ◽  
Time Interval ◽  
Ozone Monitoring Instrument ◽  
Fire Plume ◽  
Data Set ◽  
History Of ◽  
Aerosol Index

Abstract. We have quantified the relationship between Aerosol Index (AI) measurements and plume height for young biomass burning plumes using coincident Ozone Monitoring Instrument (OMI) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) measurements. This linear relationship allows the determination of high-altitude plumes wherever AI data are available, and it provides a data set for validating global fire plume heights in chemistry transport models. We find that all plumes detected from June 2006 to February 2009 with an AI value ≥9 are located at altitudes higher than 5 km. Older high-altitude plumes have lower AI values than young plumes at similar altitudes. We have examined available AI data from the OMI and TOMS instruments (1978–2009) and find that large AI plumes occur more frequently over North America than over Australia or Russia/Northeast Asia. According to the derived relationship, during this time interval, 181 plumes, in various stages of their evolution, reached altitudes above 8 km.

scholarly journals A multi-decadal history of biomass burning plume heights identified using aerosol index measurements

2010 ◽  
Vol 10 (1) ◽  
pp. 1-25 ◽  
Author(s):  
H. Guan ◽  
R. Esswein ◽  
J. Lopez ◽  
R. Bergstrom ◽  
A. Warnock ◽  
...  
Keyword(s):  
High Altitude ◽  
Biomass Burning ◽  
Northeast Asia ◽  
Time Interval ◽  
Fire Plume ◽  
Data Set ◽  
History Of ◽  
The Relationship ◽  
Aerosol Index

Abstract. We have quantified the relationship between Aerosol Index (AI) measurements and plume height for young biomass burning plumes using coincident OMI and CALIPSO measurements. This linear relationship allows the determination of high-altitude plumes wherever AI data are available, and it provides a data set for validating global fire plume injection heights in chemistry transport models. We find that all plumes detected from June 2006 to February 2009 with an AI value ≥9 are located at altitudes higher than 5 km. Older high-altitude plumes have lower AI values than young plumes at similar altitudes. We have examined available AI data from the OMI and TOMS instruments (1978–2009) and find that large AI plumes occur more frequently over North America than over Australia or Russia/Northeast Asia. According to the derived relationship, during this time interval, 181 plumes reached altitudes above 8 km. One hundred and thirty-two had injection heights ≥8 km but below 12 km, and 49 were lofted to 12 km or higher, including 14 plumes injected above 16 km.

scholarly journals Investigating the frequency and interannual variability in global above-cloud aerosol characteristics with CALIOP and OMI

2016 ◽  
Vol 16 (1) ◽  
pp. 47-69 ◽  
Author(s):  
R. Alfaro-Contreras ◽  
J. Zhang ◽  
J. R. Campbell ◽  
J. S. Reid
Keyword(s):  
Interannual Variability ◽  
Orthogonal Polarization ◽  
Cloud Detection ◽  
Ozone Monitoring Instrument ◽  
Data Set ◽  
Moderate Resolution ◽  
Resolution Imaging ◽  
Moderate Resolution Imaging Spectroradiometer ◽  
First Time ◽  
Aerosol Index

Abstract. Seven and a half years (June 2006 to November 2013) of Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aerosol and cloud layer products are compared with collocated Ozone Monitoring Instrument (OMI) aerosol index (AI) data and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) cloud products in order to investigate variability in estimates of biannual and monthly above-cloud aerosol (ACA) events globally. The active- (CALIOP) and passive-based (OMI-MODIS) techniques have their advantages and caveats for ACA detection, and thus both are used to derive a thorough and robust comparison of daytime cloudy-sky ACA distribution and climatology. For the first time, baseline above-cloud aerosol optical depth (ACAOD) and AI thresholds are derived and examined (AI  =  1.0, ACAOD  =  0.015) for each sensor. Both OMI-MODIS and CALIOP-based daytime spatial distributions of ACA events show similar patterns during both study periods (December–May) and (June–November). Divergence exists in some regions, however, such as Southeast Asia during June through November, where daytime cloudy-sky ACA frequencies of up to 10 % are found from CALIOP yet are non-existent from the OMI-based method. Conversely, annual cloudy-sky ACA frequencies of 20–30 % are reported over northern Africa from the OMI-based method yet are largely undetected by the CALIOP-based method. Using a collocated OMI-MODIS-CALIOP data set, our study suggests that the cloudy-sky ACA frequency differences between the OMI-MODIS- and CALIOP-based methods are mostly due to differences in cloud detection capability between MODIS and CALIOP as well as QA flags used. An increasing interannual variability of  ∼  0.3–0.4 % per year (since 2009) in global monthly cloudy-sky ACA daytime frequency of occurrence is found using the OMI-MODIS-based method. Yet, CALIOP-based global daytime ACA frequencies exhibit a near-zero interannual variability. Further analysis suggests that the OMI-derived interannual variability in cloudy-sky ACA frequency may be affected by OMI row anomalies in later years. A few regions are found to have increasing slopes in interannual variability in cloudy-sky ACA frequency, including the Middle East and India. Regions with slightly negative slopes of the interannual variability in cloudy-sky ACA frequencies are found over South America and China, while remaining regions in the study show nearly zero change in ACA frequencies over time. The interannual variability in ACA frequency is not, however, statistically significant on both global and regional scales, given the relatively limited sample sizes. A longer data record of ACA events is needed in order to establish significant trends of ACA frequency regionally and globally.

scholarly journals The Pristine Inner Galaxy Survey (PIGS) II: Uncovering the most metal-poor populations in the inner Milky Way

2020 ◽  
Vol 496 (4) ◽  
pp. 4964-4978 ◽  
Author(s):  
Anke Arentsen ◽  
Else Starkenburg ◽  
Nicolas F Martin ◽  
David S Aguado ◽  
Daniel B Zucker ◽  
...  
Keyword(s):  
Milky Way ◽  
Dynamical Evolution ◽  
Spectral Library ◽  
Data Set ◽  
Unique Data ◽  
Horizontal Branch Stars ◽  
History Of ◽  
Low Metallicity

ABSTRACT Metal-poor stars are important tools for tracing the early history of the Milky Way, and for learning about the first generations of stars. Simulations suggest that the oldest metal-poor stars are to be found in the inner Galaxy. Typical bulge surveys, however, lack low metallicity ($\rm {[Fe/H]} \lt -1.0$) stars because the inner Galaxy is predominantly metal-rich. The aim of the Pristine Inner Galaxy Survey (PIGS) is to study the metal-poor and very metal-poor (VMP, $\rm {[Fe/H]} \lt -2.0$) stars in this region. In PIGS, metal-poor targets for spectroscopic follow-up are selected from metallicity-sensitive CaHK photometry from the CFHT. This work presents the ∼250 deg2 photometric survey as well as intermediate-resolution spectroscopic follow-up observations for ∼8000 stars using AAOmega on the AAT. The spectra are analysed using two independent tools: ULySS with an empirical spectral library, and FERRE with a library of synthetic spectra. The comparison between the two methods enables a robust determination of the stellar parameters and their uncertainties. We present a sample of 1300 VMP stars – the largest sample of VMP stars in the inner Galaxy to date. Additionally, our spectroscopic data set includes ∼1700 horizontal branch stars, which are useful metal-poor standard candles. We furthermore show that PIGS photometry selects VMP stars with unprecedented efficiency: 86 per cent/80 per cent (lower/higher extinction) of the best candidates satisfy $\rm {[Fe/H]} \lt -2.0$, as do 80 per cent/63 per cent of a larger, less strictly selected sample. We discuss future applications of this unique data set that will further our understanding of the chemical and dynamical evolution of the innermost regions of our Galaxy.

scholarly journals Ancient Hybridization with an Unknown Population Facilitated High-Altitude Adaptation of Canids

2020 ◽  
Vol 37 (9) ◽  
pp. 2616-2629 ◽  
Author(s):  
Ming-Shan Wang ◽  
Sheng Wang ◽  
Yan Li ◽  
Yadvendradev Jhala ◽  
Mukesh Thakur ◽  
...  
Keyword(s):  
High Altitude ◽  
Evolutionary History ◽  
Nuclear Genome ◽  
Genetic Introgression ◽  
Data Set ◽  
Whole Genomes ◽  
Ancient Lineage ◽  
History Of ◽  
Evolutionary Trajectories ◽  
Altitude Adaptation

Abstract Genetic introgression not only provides material for adaptive evolution but also confounds our understanding of evolutionary history. This is particularly true for canids, a species complex in which genome sequencing and analysis has revealed a complex history of admixture and introgression. Here, we sequence 19 new whole genomes from high-altitude Tibetan and Himalayan wolves and dogs and combine these into a larger data set of 166 whole canid genomes. Using these data, we explore the evolutionary history and adaptation of these and other canid lineages. We find that Tibetan and Himalayan wolves are closely related to each other, and that ∼39% of their nuclear genome is derived from an as-yet-unrecognized wolf-like lineage that is deeply diverged from living Holarctic wolves and dogs. The EPAS1 haplotype, which is present at high frequencies in Tibetan dog breeds and wolves and confers an adaptive advantage to animals living at high altitudes, was probably derived from this ancient lineage. Our study underscores the complexity of canid evolution and demonstrates how admixture and introgression can shape the evolutionary trajectories of species.

scholarly journals Determination of Acquisition Frequency for Intrafractional Motion of Pancreas in CyberKnife Radiotherapy

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Huailing Zhang ◽  
Guoru Zhao ◽  
David Djajaputra ◽  
Yaoqin Xie
Keyword(s):  
Effective Means ◽  
Time Interval ◽  
Data Sets ◽  
Data Set ◽  
X Ray ◽  
Adequate Dose ◽  
Time Stamps ◽  
Movement Distance ◽  
Intrafractional Motion

Purpose.To report the characteristics of pancreas motion as tracked using implanted fiducials during radiotherapy treatments with CyberKnife.Methods and Materials. Twenty-nine patients with pancreas cancer treated using CyberKnife system were retrospectively selected for this study. During the treatment, the deviation is examined every 3-4 nodes (~45 s interval) and compensated by the robot. The pancreas displacement calculated from X-ray images acquired within the time interval between two consecutive couch motions constitute a data set.Results. A total of 498 data sets and 4302 time stamps of X-ray images were analyzed in this study. The average duration for each data set is 634 s. The location of the pancreas becomes more dispersed as the time elapses. The acquisition frequency depends on the prespecified movement distance threshold of pancreas. If the threshold between two consecutive images is 1 mm, the acquisition frequency should be less than 30 s, while if the threshold is 2 mm, the acquisition frequency can be around 1 min.Conclusions. The pancreas target moves significantly and unpredictably during treatment. Effective means of compensating the intrafractional movement is critical to ensure adequate dose coverage of the tumor target.

scholarly journals An Aerosol Optical Depth time series 1982–2014 for atmospheric correction based on OMI and TOMS Aerosol Index

2016 ◽  
Author(s):  
Emmihenna Jääskeläinen ◽  
Terhikki Manninen ◽  
Johanna Tamminen ◽  
Marko Laine
Keyword(s):  
Time Series ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Surface Albedo ◽  
Atmospheric Correction ◽  
In Situ Measurements ◽  
Ozone Monitoring Instrument ◽  
Data Set ◽  
Aerosol Index

Abstract. The atmospheric correction of old optical satellite data is problematic, because corresponding Aerosol Optical Depth (AOD) measurements in the visible wavelength range do not exist. The construction of an AOD time series for atmospheric correction purposes to cover the period 1982–2014 is described in this paper. The AOD estimates are calculated from the Aerosol Index (AI) data from the Total Ozone Mapping Spectrometer (TOMS) and the Ozone Monitoring Instrument (OMI). We apply this time series to the generation of the surface albedo data set CLARA-A2-SAL (the Surface ALbedo from the CM SAF cLoud, Albedo and RAdiation data set, the second version). The constructed AOD time series is temporally homogeneous, and it has sufficient quality compared to the AOD from OMI observations and from in situ measurements. The simulated atmospheric correction calculations, where the constructed AOD data are used as an aerosol input, are similar to the simulations where the aerosol information from OMI and in situ measurements is used. Also, the simulations show that the use of the constructed AOD time series decreases the surface reflectance values (the output of the atmospheric correction) globally compared to the use of the constant AOD value 0.1.

State-by-State Use of AMA Guides

2019 ◽  
Vol 24 (5) ◽  
pp. 3-7, 16
Keyword(s):  
Expert Testimony ◽  
Narrow Range ◽  
The United States ◽  
Workers Compensation ◽  
Federal Employees ◽  
Permanent Disability ◽  
Sixth Edition ◽  
History Of ◽  
Canadian Provinces

Abstract This article presents a history of the origins and development of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), from the publication of an article titled “A Guide to the Evaluation of Permanent Impairment of the Extremities and Back” (1958) until a compendium of thirteen guides was published in book form in 1971. The most recent, sixth edition, appeared in 2008. Over time, the AMA Guides has been widely used by US states for workers’ compensation and also by the Federal Employees Compensation Act, the Longshore and Harbor Workers’ Compensation Act, as well as by Canadian provinces and other jurisdictions around the world. In the United States, almost twenty states have developed some form of their own impairment rating system, but some have a narrow range and scope and advise evaluators to consult the AMA Guides for a final determination of permanent disability. An evaluator's impairment evaluation report should clearly document the rater's review of prior medical and treatment records, clinical evaluation, analysis of the findings, and a discussion of how the final impairment rating was calculated. The resulting report is the rating physician's expert testimony to help adjudicate the claim. A table shows the edition of the AMA Guides used in each state and the enabling statute/code, with comments.

Integrative Approach in Law Understanding: the History of the Origin of Ideas and the Current State

2020 ◽  
Vol 2 (1) ◽  
pp. 115-130
Author(s):  
R. R. Palekha ◽  
Keyword(s):  
Central Place ◽  
Scientific Basis ◽  
Integrative Approach ◽  
Current State ◽  
History Of ◽  
Legal Thinking ◽  
Reliable Knowledge ◽  
The Right ◽  
Fat Formulation

Introduction. Right understanding is the most live, interesting and, at the same time, the uncertain and changeable area of researches which takes the central place as in the general theory of the right, and gains the increasing value in industry jurisprudence that is connected with its considerable teoretiko-methodological and applied potential which is shown in spheres of lawmaking and law-enforcement activity. Thus, right understanding represents research tools of the subject of knowledge which allow to study all range legal and, the based on them, state phenomena for the purpose of obtaining reliable knowledge of state and legal reality. In this regard integrative approach in right understanding which has rich history of the formation and development is of special interest, allows to perceive the right as integrally complete phenomenon, as much as possible retrieves its regulatory abilities and, provides achievement of criteria of scientific research: comprehensiveness, objectivity, historicism. Materials and Methods. In article an attempt of the analysis of integrative approach in right understanding from a position of history of origin of his ideas and assessment of the current state is made. A result of studying of scientific literature, generalization and comparison of the different points of view fat formulation of author’s determination of category “right understanding” and submission of the evidence-based integrative theory of right understanding which as much as possible conforms to requirements of time and has essential regulatory and guarding potential. Results. In article the category right understanding is comprehensively considered, different integrative theories of right understanding from a position of their origin and development are submitted, the value of modern integrative approach in right understanding is shown, perspectives of its further development are evaluated. Discussion and Conclusion. The author comes to the conclusion about the theoretical and methodological consistency and inevitability of the integrative approach in law understanding, which acts as a scientifically grounded type of legal thinking capable of comprehending the law on a truly scientific basis.

The Earliest Christian Communities in Southeast and Northeast Asia: An Outline of the Evidence Available in Seven Countries before A.D. 1500

1991 ◽  
Vol 19 (2) ◽  
pp. 203-215 ◽  
Author(s):  
John C. England
Keyword(s):  
East Asia ◽  
Northeast Asia ◽  
Christian Communities ◽  
Christian Churches ◽  
Eastern Christianity ◽  
History Of ◽  
Material Evidence ◽  
Central South

The history of Eastern Christianity in central, south, and east Asia prior to A.D. 1500 is rich and extensive, yet has been largely ignored. Material evidence now available from southeast and northeast Asia shows that Christian communities were present in seven countries for different periods between the sixth and fifteenth centuries. Often termed “Nestorian,” or “Jacobite,” these communities have left a diversity of remains—epigraphical, architectural, sculptural, documentary—which testify to their presence, as far northeast as Japan and southeast as far as Indonesia. The glimpses of Christian churches in medieval Asia afforded by the evidence from these and other regions of Asia offer alternatives to Westernized patterns of mission, and question many assumptions concerning the history and character of Christian presence in the region.

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