scholarly journals Southern hemispheric halon trends and global halon emissions, 1978–2011

2012 ◽  
Vol 12 (11) ◽  
pp. 29289-29324 ◽  
Author(s):  
M. J. Newland ◽  
C. E. Reeves ◽  
D. E. Oram ◽  
J. C. Laube ◽  
W. T. Sturges ◽  
...  
Keyword(s):  
Steady State ◽  
Atmospheric Model ◽  
Two Dimensional ◽  
Top Down ◽  
Bottom Up ◽  
Mixing Ratios ◽  
The Past ◽  
Cape Grim

Abstract. The atmospheric records of four halons, H-1211 (CBrClF2), H-1301 (CBrF3), H-2402 (CBrF2CBrF2) and H-1202 (CBr2F2), measured from air collected at Cape Grim, Tasmania between 1978 and 2011, are reported. Mixing ratios of H-1211, H-2402 and H-1202 began to decline in the early to mid-2000s but those of H-1301 continue to increase throughout the record. These trends are compared to those reported by NOAA (National Oceanic and Atmospheric Administration) and AGAGE (Advanced Global Atmospheric Experiment). The continued increase of H-1301 mixing ratios means that the contribution of the halons to total tropospheric bromine is not declining. Top-down global annual emissions of the halons were derived using a two-dimensional atmospheric model. The emissions of all four have decreased since peaking in the late 1980s–mid 1990s but this decline has slowed recently, particularly for H-1301 and H-2402 which have shown no decrease in emissions over the past five years. The UEA top-down model derived emissions are compared to those reported using a top-down approach by NOAA and AGAGE and the bottom-up estimates of HTOC (Halons Technical Options Committee). Additionally results are presented that suggest that H-1202 emissions are linked to H-1211 emissions rather than H-1211 production. Finally revised steady state atmospheric lifetimes are reported as 14 yr for H-1211, 75 yr for H-1301, 17 yr for H-2402 and 2.6 yr for H-1202. These revised lifetimes would reduce the estimated existing bank of H-1211 by over 80% to 10 Gg while increasing the H-1301 bank by 15% to 49 Gg.

scholarly journals Southern hemispheric halon trends and global halon emissions, 1978–2011

2013 ◽  
Vol 13 (11) ◽  
pp. 5551-5565 ◽  
Author(s):  
M. J. Newland ◽  
C. E. Reeves ◽  
D. E. Oram ◽  
J. C. Laube ◽  
W. T. Sturges ◽  
...  
Keyword(s):  
Steady State ◽  
Atmospheric Model ◽  
Production Data ◽  
Two Dimensional ◽  
Top Down ◽  
East Anglia ◽  
Mixing Ratios ◽  
The Past ◽  
Alternative Set ◽  
Cape Grim

Abstract. The atmospheric records of four halons, H-1211 (CBrClF2), H-1301 (CBrF3), H-2402 (CBrF2CBrF2) and H-1202 (CBr2F2), measured from air collected at Cape Grim, Tasmania, between 1978 and 2011, are reported. Mixing ratios of H-1211, H-2402 and H-1202 began to decline in the early to mid-2000s, but those of H-1301 continue to increase up to mid-2011. These trends are compared to those reported by NOAA (National Oceanic and Atmospheric Administration) and AGAGE (Advanced Global Atmospheric Experiment). The observations suggest that the contribution of the halons to total tropospheric bromine at Cape Grim has begun to decline from a peak in 2008 of about 8.1 ppt. An extrapolation of halon mixing ratios to 2060, based on reported banks and predicted release factors, shows this decline becoming more rapid in the coming decades, with a contribution to total tropospheric bromine of about 3 ppt in 2060. Top-down global annual emissions of the halons were derived using a two-dimensional atmospheric model. The emissions of all four have decreased since peaking in the late 1980s–mid-1990s, but this decline has slowed recently, particularly for H-1301 and H-2402 which have shown no decrease in emissions over the past five years. The UEA (University of East Anglia) top-down model-derived emissions are compared to those reported using a top-down approach by NOAA and AGAGE and the bottom-up estimates of HTOC (Halons Technical Options Committee). The implications of an alternative set of steady-state atmospheric lifetimes are discussed. Using a lifetime of 14 yr or less for H-1211 to calculate top-down emissions estimates would lead to small, or even negative, estimated banks given reported production data. Finally emissions of H-1202, a product of over-bromination during the production process of H-1211, have continued despite reported production of H-1211 ceasing in 2010. This raises questions as to the source of these H-1202 emissions.

“Forward to David the Builder!” Georgia's (re)turn to language-centered nationalism

2016 ◽  
Vol 44 (4) ◽  
pp. 522-542 ◽  
Author(s):  
Christofer Berglund
Keyword(s):  
Large Scale ◽  
Nation Building ◽  
The State ◽  
Top Down ◽  
Bottom Up ◽  
The Past ◽  
Building Project ◽  
The Rose ◽  
State Language

After the Rose Revolution, President Saakashvili tried to move away from the exclusionary nationalism of the past, which had poisoned relations between Georgians and their Armenian and Azerbaijani compatriots. His government instead sought to foster an inclusionary nationalism, wherein belonging was contingent upon speaking the state language and all Georgian speakers, irrespective of origin, were to be equals. This article examines this nation-building project from a top-down and bottom-up lens. I first argue that state officials took rigorous steps to signal that Georgian-speaking minorities were part of the national fabric, but failed to abolish religious and historical barriers to their inclusion. I next utilize a large-scale, matched-guise experiment (n= 792) to explore if adolescent Georgians ostracize Georgian-speaking minorities or embrace them as their peers. I find that the upcoming generation of Georgians harbor attitudes in line with Saakashvili's language-centered nationalism, and that current Georgian nationalism therefore is more inclusionary than previous research, or Georgia's tumultuous past, would lead us to believe.

scholarly journals Beyond the Post-Sovereign State?: The Past, Present, and Future of Constitutional Pluralism

2019 ◽  
Vol 21 ◽  
pp. 6-23
Author(s):  
Michael WILKINSON
Keyword(s):  
Political Economy ◽  
European Integration ◽  
Recent Decade ◽  
Popular Sovereignty ◽  
Top Down ◽  
Bottom Up ◽  
Sovereign State ◽  
European State ◽  
The Past ◽  
Constitutional Pluralism

AbstractConstitutional pluralism is a theory for the post-sovereign European state. This only makes sense historically, emerging out of postwar European reconstruction through the repression of popular sovereignty and restraining of democracy, including through the project of European integration. It became unsettled at Maastricht and evolved from a series of irritants into a full-blown crisis in the recent decade, with sovereignty claims returning both from the bottom-up and the top-down, to the extent that we can legitimately ask whether we are now moving ‘beyond the post-sovereign state’? Constitutional pluralist literature fails to capture this in that evades material issues of democracy and political economy.

Contemporary Issues and Christian Models of Integration: Into the Modern/Postmodern Age

1995 ◽  
Vol 23 (1) ◽  
pp. 3-14 ◽  
Author(s):  
John A. Ingram
Keyword(s):  
Present Article ◽  
Model Building ◽  
Social Practices ◽  
Top Down ◽  
Bottom Up ◽  
Comprehensive View ◽  
The Past ◽  
Psychological Theories ◽  
Proposed Model ◽  
Dsm Iv

Model building in Christian psychology has gradually become increasingly outdated and unsophisticated over the past decade, particularly in light of postmodern challenges to the limitations of received modern scientific perspectives and social practices. The present article draws from Rychlak's (1993) “complementarity” model, Sperry's (1993) “bidirectional determinism” concept, and Engel's (1977) biopsychosocial formulation to develop a multiperspectival, holistic framework drawing on the strengths of both modern and postmodern approaches. The proposed model includes inferences from both top down and bottom up formulations, as well as potential for interactions between or among any of the various “groundings” for psychological theories. Such a model seems more faithful to both biblical and scientific perspectives, and thus may provide a more accurate and comprehensive view of persons to facilitate more effective research and treatment. A clinical example is provided with DSM-IV descriptive and criterion referents.

Participation or Pathology: Contradictory Tensions in Area-Based Policy

2004 ◽  
Vol 3 (2) ◽  
pp. 87-96 ◽  
Author(s):  
Pete Alcock
Keyword(s):  
Social Policy ◽  
Social Exclusion ◽  
Government Policy ◽  
Service Provision ◽  
Central Feature ◽  
Top Down ◽  
Bottom Up ◽  
Policy Practice ◽  
The Past ◽  
The Uk

This paper discusses some of the tensions revealed in the development and implementation of recent area-based approaches to social policy in England. Such programmes are now a central feature of Government policy practice, although similar programmes have been developed in the past in the UK and other welfare capitalist countries. They reflect concerns to combat social exclusion and ‘join-up’ service provision. They are also evidence of a shift towards more agency based policy practice – from ‘top-down’ to ‘bottom-up’ planning. Thus participation of citizens is a key element in all programmes. Some of the problems of securing such participation are discussed, including in particular the tendency for expectations of participation to lead to pathological interpretations of the causes of (and solutions too) social exclusion.

scholarly journals A review of bottom-up vs. top-down control of sponges on Caribbean fore-reefs: what’s old, what’s new, and future directions

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4343 ◽  
Author(s):  
Joseph R. Pawlik ◽  
Tse-Lynn Loh ◽  
Steven E. McMurray
Keyword(s):  
Community Structure ◽  
Past Research ◽  
Fish Predation ◽  
Sponge Species ◽  
Top Down ◽  
Bottom Up ◽  
Fore Reef ◽  
The Past ◽  
The Impact ◽  
Hawksbill Turtles

Interest in the ecology of sponges on coral reefs has grown in recent years with mounting evidence that sponges are becoming dominant members of reef communities, particularly in the Caribbean. New estimates of water column processing by sponge pumping activities combined with discoveries related to carbon and nutrient cycling have led to novel hypotheses about the role of sponges in reef ecosystem function. Among these developments, a debate has emerged about the relative effects of bottom-up (food availability) and top-down (predation) control on the community of sponges on Caribbean fore-reefs. In this review, we evaluate the impact of the latest findings on the debate, as well as provide new insights based on older citations. Recent studies that employed different research methods have demonstrated that dissolved organic carbon (DOC) and detritus are the principal sources of food for a growing list of sponge species, challenging the idea that the relative availability of living picoplankton is the sole proxy for sponge growth or abundance. New reports have confirmed earlier findings that reef macroalgae release labile DOC available for sponge nutrition. Evidence for top-down control of sponge community structure by fish predation is further supported by gut content studies and historical population estimates of hawksbill turtles, which likely had a much greater impact on relative sponge abundances on Caribbean reefs of the past. Implicit to investigations designed to address the bottom-up vs. top-down debate are appropriate studies of Caribbean fore-reef environments, where benthic communities are relatively homogeneous and terrestrial influences and abiotic effects are minimized. One recent study designed to test both aspects of the debate did so using experiments conducted entirely in shallow lagoonal habitats dominated by mangroves and seagrass beds. The top-down results from this study are reinterpreted as supporting past research demonstrating predator preferences for sponge species that are abundant in these lagoonal habitats, but grazed away in fore-reef habitats. We conclude that sponge communities on Caribbean fore-reefs of the past and present are largely structured by predation, and offer new directions for research, such as determining the environmental conditions under which sponges may be food-limited (e.g., deep sea, lagoonal habitats) and monitoring changes in sponge community structure as populations of hawksbill turtles rebound.

Moderne Q’eqchi’-Maya-Identität und der antike Maya-Ort Tamarindito in Guatemala

Anthropos ◽  
2019 ◽  
Vol 114 (1) ◽  
pp. 19-32
Author(s):  
Markus Eberl ◽  
Santiago Cho Coc
Keyword(s):  
Classic Maya ◽  
National Identities ◽  
Top Down ◽  
Bottom Up ◽  
The Past ◽  
Tropical Lowlands ◽  
Ritual Practices

Guatemala’s Q’eqchi’-Maya employ the past to construct their identity. In modern states, leaders like Mussolini or Hitler appropriated the past to shape national identities. Unlike these top-down approaches, the Q’eqchi’ offer a bottom-up perspective. In the Guatemalan highlands, Q’eqchi’ ritual practices involve the tzuul taq’a’s, supernatural beings linked to mountains and owners of the land. Recently many Q’eqchi’ migrated into the tropical lowlands and settled among Classic Maya ruins. Through questionnaires and interviews we reconstruct the complex ways in which Q’eqchi’ transfer the tzuul taq’a’ to the lowlands and appropriate their new surroundings both ideologically and physically.

scholarly journals Canopy-scale flux measurements and bottom-up emission estimates of volatile organic compounds from a mixed oak and hornbeam forest in northern Italy

2016 ◽  
Vol 16 (11) ◽  
pp. 7149-7170 ◽  
Author(s):  
W. Joe F. Acton ◽  
Simon Schallhart ◽  
Ben Langford ◽  
Amy Valach ◽  
Pekka Rantala ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Transfer Reaction ◽  
Proton Transfer Reaction ◽  
Northern Italy ◽  
Top Down ◽  
Bottom Up ◽  
Mixing Ratios ◽  
Volatile Organic ◽  
Leaf Level ◽  
Tof Ms

Abstract. This paper reports the fluxes and mixing ratios of biogenically emitted volatile organic compounds (BVOCs) 4 m above a mixed oak and hornbeam forest in northern Italy. Fluxes of methanol, acetaldehyde, isoprene, methyl vinyl ketone + methacrolein, methyl ethyl ketone and monoterpenes were obtained using both a proton-transfer-reaction mass spectrometer (PTR-MS) and a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) together with the methods of virtual disjunct eddy covariance (using PTR-MS) and eddy covariance (using PTR-ToF-MS). Isoprene was the dominant emitted compound with a mean daytime flux of 1.9 mg m−2 h−1. Mixing ratios, recorded 4 m above the canopy, were dominated by methanol with a mean value of 6.2 ppbv over the 28-day measurement period. Comparison of isoprene fluxes calculated using the PTR-MS and PTR-ToF-MS showed very good agreement while comparison of the monoterpene fluxes suggested a slight over estimation of the flux by the PTR-MS. A basal isoprene emission rate for the forest of 1.7 mg m−2 h−1 was calculated using the Model of Emissions of Gases and Aerosols from Nature (MEGAN) isoprene emission algorithms (Guenther et al., 2006). A detailed tree-species distribution map for the site enabled the leaf-level emission of isoprene and monoterpenes recorded using gas-chromatography mass spectrometry (GC–MS) to be scaled up to produce a bottom-up canopy-scale flux. This was compared with the top-down canopy-scale flux obtained by measurements. For monoterpenes, the two estimates were closely correlated and this correlation improved when the plant-species composition in the individual flux footprint was taken into account. However, the bottom-up approach significantly underestimated the isoprene flux, compared with the top-down measurements, suggesting that the leaf-level measurements were not representative of actual emission rates.

scholarly journals Brief communication: Comparing top-down and bottom-up paradigms for global flood hazard mapping

2020 ◽  
Author(s):  
Giuliano Di Baldassarre ◽  
Fernando Nardi ◽  
Antonio Annis ◽  
Vincent Odongo ◽  
Maria Rusca ◽  
...  
Keyword(s):  
Flood Risk ◽  
Flood Hazard ◽  
Hazard Mapping ◽  
Top Down ◽  
Bottom Up ◽  
The Past ◽  
Floodplain Mapping

Abstract. Global floodplain mapping has rapidly progressed over the past few years. Different methods have been proposed to identify areas prone to flooding, resulting into a plethora of freely available products. Here we assess the potential and limitations of two main paradigms, and provide guidance on the use of these global products in assessing flood risk in data-poor regions.

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