Projected changes in vertical temperature profiles for Australasia     

Ji  Fei  Evans  Jason P.  Di Virgilio  Giovanni  Nishant  Nidhi  Di Luca  Alejandro  Herold  Nicholas  Downes  Stephanie M.  Tam  Eugene  Beyer  Kathleen 《Climate Dynamics》2020,55(9-10):2453-2468

The vertical temperature profile in the atmosphere reflects a balance between radiative and convective processes and interactions with the oceanic and land surfaces. Changes in vertical temperature profiles can affect atmospheric stability, which in turn can impact various aspects of weather systems. In this study, we analyzed recent-past trends of temperature over the Australian region using a homogenized monthly upper-air temperature dataset and four reanalysis datasets (NCEP, ERA-Interim, JRA-55 and MERRA). We also used outputs of 12 historical and future regional climate model (RCM) simulations from the NSW/ACT (New South Wales/Australian Capital Territory) Regional Climate Modelling (NARCliM) project and 6 RCM simulations from the CORDEX (Coordinated Regional Downscaling Experiment) Australasian project to investigate projected changes in vertical temperature profiles. The results show that the currently observed positive trend in the troposphere and negative trend in the lower stratosphere will continue in the future with significant warming over the whole troposphere and largest over the middle to upper troposphere. The increasing temperatures are found to be latitude-dependent with clear seasonal variations, and a strong diurnal variation for the near surface layers and upper levels in tropical regions. Changes in the diurnal variability indicate that near surface layers will be less stable in the afternoon leading to conditions favoring convective systems and more stable in the early morning which is favorable for temperature inversions. The largest differences of future changes in temperature between the simulations are associated with the driving GCMs, suggesting that large-scale circulation plays a dominant role in regional atmospheric temperature change.

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Seasonal patterns in zooplankton community structure on the Newfoundland and Labrador Shelf     

Pierre Pepin  Eugene Colbourne  Gary Maillet 《Progress in Oceanography》2011,91(3):273-285

We report on the patterns in zooplankton community structure on the Newfoundland and Labrador Shelf from seasonal collections along oceanographic sections during 2000–2007. We use a combination of constrained and unconstrained multivariate methods to assess latitudinal and cross shelf patterns in community structure. Both physical and biological features of the region are dominated by the cross-shelf gradient in water mass characteristics although there is evidence of a latitudinal gradient that may be a reflection of the influence of freshwater outflow from the Arctic. All analyses reveal a strong and consistent pattern in species composition among water masses that extends across spring, summer and autumn, although there are some variations that occur among seasons that reflect differences in development state of certain taxa. The strong association between community structure and water mass characteristics in the region may be the result of the Newfoundland and Labrador Shelf being at the intersection of several major oceanographic domains, bounded by strong Labrador and Gulf Stream currents, that allows the formation and persistence of well defined zooplankton communities. Our findings have implications for the region’s potential as a monitoring location for long term changes in ocean state.  相似文献   

Role of wave–mean flow interaction in sun–climate connections: Historical overview and some new interpretations and results     

Terrence R. Nathan  John R. Albers  Eugene C. Cordero 《Journal of Atmospheric and Solar》2011,73(11-12):1594-1605

Quasi-decadal variations in solar irradiance – termed the 11-year solar cycle (SC) – have been linked to variations in a variety of atmospheric circulation features, including the polar vortex, the Brewer–Dobson circulation, and the quasi-biennial oscillation. These features share an underlying commonality: they are all rooted in wave–mean flow interaction. The purpose of this paper is to provide a historical overview of the connection between the SC and wave–mean flow interaction and to propose a more complete theoretical framework for solar modulated wave–mean flow interaction that includes both zonal-mean and zonally asymmetric ozone as intermediaries for communicating variations in solar spectral irradiance to the climate system. We solve a quasi-geostrophic model using the WKB formalism to highlight the physics connecting the SC to planetary wave-drag. Numerical results show the importance of the zonally asymmetric ozone field in mediating the effects of solar variability to the wave-driven circulation in the middle atmosphere.  相似文献   

Are we loving 'em to death?     

Shinn EA 《Marine pollution bulletin》2011,62(12):2581-2583

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Structure analysis on synthetic emerald crystals     

Pei-Lun Lee  Jiann-Shing Lee  Eugene Huang  Ju-Hsiou Liao 《Physics and Chemistry of Minerals》2013,40(5):439-446

Single crystals of emerald synthesized by means of the flux method were adopted for crystallographic analyses. Emerald crystals with a wide range of Cr³⁺-doping content up to 3.16 wt% Cr₂O₃ were examined by X-ray single crystal diffraction refinement method. The crystal structures of the emerald crystals were refined to R ₁ (all data) of 0.019–0.024 and wR ₂ (all data) of 0.061–0.073. When Cr³⁺ substitutes for Al³⁺, the main adjustment takes place in the Al-octahedron and Be-tetrahedron. The effect of substitution of Cr³⁺ for Al³⁺ in the beryl structure results in progressively lengthening of the Al–O distance, while the length of the other bonds remains nearly unchanged. The substitution of Cr³⁺ for Al³⁺ may have caused the expansion of a axis, while keeping the c axis unchanged in the emerald lattice. As a consequence, the Al–O–Si and Al–O–Be bonding angles are found to decrease, while the angle of Si–O–Be increases as the Al–O distance increases during the Cr replacement.  相似文献   

“Bush Doctors and Wild Medicine”: The Scale of Trade in Cape Town's Informal Economy of Wild-Harvested Medicine and Traditional Healing     

Leif M. Petersen  Andrew J. E. Charman  Eugene J. Moll  Ray J. Collins  Marc T. Hockings 《社会与自然资源》2014,27(3):315-336

South Africa's organically emerged cultural business of traditional healing is almost exclusively reliant on wild-harvested resources extracted from wilderness areas or open-access commons. The wild medicine business has been described for much of South Africa, although is little understood in Cape Town, the urban centerpiece of the Cape Floristic Region (CFR). A census of different traditional healer typologies in five typical working-class residential areas (representing ～71,500 residents) was conducted to assess the nature and extent of traditional medicine harvesting and trade. Extrapolating these findings for the city reveals a local industry of more than 15,000 practitioners collectively conducting trade worth US $15.6 million per year. More than 40% of the volume of traditional medicines traded in the city is harvested from the CFR. Future conservation approaches must consider that the business of traditional healing and dispensing wild-harvested medicines is both economically important and culturally entrenched.  相似文献   

Policy Boosterism,Policy Mobilities,and the Extrospective City   总被引：1，自引：1，他引：0  

Eugene McCann 《Urban geography》2013,34(1):5-29

Abstract

This study develops the notion of “policy boosterism,” a subset of traditional branding and marketing activities that involves the active promotion of locally developed and/or locally successful policies, programs, or practices across wider geographical fields as well as to broader communities of interested peers. It is argued that policy boosterism is (1) an important element of how urban policy actors engage with global communities of professional peers and with local residents, and (2) a useful concept with which to interrogate and understand how policies and policy knowledge are mobilized among cities. A conceptualization of policy boosterism and its role in global-urban policymaking is developed by combining insights from the burgeoning “policy mobilities” literature with those of the longstanding literature on entrepreneurial city marketing. It is supported by illustrative examples of policy boosterism in Vancouver: the city's Greenest City and Green Capital initiatives, the use of the term “Vancouverism” among the city's urban design community, and demonstrations of new urban technologies during the 2010 Winter Olympics that were used to market a particular vision of the city's governance to people from elsewhere, but also—crucially—to local audiences. The article concludes by highlighting four foci that might frame future work at the intersections of policy boosterism and policy mobilities.  相似文献   

Distribution and morphology of mud volcanoes and other fluid flow-related lake-bed structures in Lake Baikal, Russia     

Myriam Cuylaerts  Lieven Naudts  Robbert Casier  Andrey V. Khabuev  Oleg V. Belousov  Eugene E. Kononov  Oleg Khlystov  Marc De Batist 《Geo-Marine Letters》2012,32(5-6):383-394

New high-resolution multibeam bathymetry data recorded in 2009 in the deepest lake in the World, Lake Baikal, Siberia, enabled a better understanding of the morphology of ten known lake-bed structures—the Bolshoy, Malenki, Malyutka and Stari mud volcanoes in the South Baikal Basin, the K1–4 structures in the Selenga delta, and the Novosibirsk and St. Petersburg structures in the Central Baikal Basin—and also the discovery of 29 new lake-bed structures. These new structures are the S1, Tolstiy, mTSG and S2 in the South Baikal Basin, the P1–P4, P6–P19 and K5–K8 in the Selenga delta accommodation zone, and the C1, C3 and C4 edifices in the Central Baikal Basin. In all, 39 positive relief structures were identified and their large-scale distribution mapped. Based on their typical shape, the observation of high-reflectivity areas on side-scan sonar data records, and evidence of feeder channels on subsurface data, these structures can be classified as mud volcanoes. This has already been confirmed in other publications for the Bolshoy, Malenki and K2 structures, by the recovery of mud breccias in sediment cores. Most structures occur on or near faults and have orientations parallel with the major faults and main stress orientations in the basins, suggesting a strong structural control on the formation of the mud volcanoes. Their slopes are generally steeper than 5°, consistent with interpretation as mud cones formed by high-viscosity, stiff mud plugs. Only few structures appear to be characterised by a crater, in which case this apparent crater seems to be formed by the coalescence of several single cones, leaving a depression in the centre. Some structures have a moat, which has probably an erosional origin. Furthermore, three depressions have been found, named P5, P20 and C2, which are suggested to be pockmarks.  相似文献   

Binary asteroid orbit expansion due to continued YORP spin-up of the primary and primary surface particle motion     

Eugene G. Fahnestock  Daniel J. Scheeres 《Icarus》2009,201(1):135-152

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Vulnerability to epidemic malaria in the highlands of Lake Victoria basin: the role of climate change/variability, hydrology and socio-economic factors     

Shem O. Wandiga  Maggie Opondo  Daniel Olago  Andrew Githeko  Faith Githui  Michael Marshall  Tim Downs  Alfred Opere  Christopher Oludhe  Gilbert O. Ouma  Pius Z. Yanda  Richard Kangalawe  Robert Kabumbuli  James Kathuri  Eugene Apindi  Lydia Olaka  Laban Ogallo  Paul Mugambi  Rehema Sigalla  Robinah Nanyunja  Timothy Baguma  Pius Achola 《Climatic change》2010,99(3-4):473-497

Endemic malaria in most of the hot and humid African climates is the leading cause of morbidity and mortality. In the last twenty or so years the incidence of malaria has been aggravated by the resurgence of highland malaria epidemics which hitherto had been rare. A close association between malaria epidemics and climate variability has been reported but not universally accepted. Similarly, the relationship between climate variability, intensity of disease mortality and morbidity coupled with socio-economic factors has been mooted. Analyses of past climate (temperature and precipitation), hydrological and health data (1961–2001), and socio-economics status of communities from the East African highlands confirm the link between climate variability and the incidence and severity of malaria epidemics. The communities in the highlands that have had less exposure to malaria are more vulnerable than their counterparts in the lowlands due to lack of clinical immunity. However, the vulnerability of human health to climate variability is influenced by the coping and adaptive capacities of an individual or community. Surveys conducted among three communities in the East African highlands reveal that the interplay of poverty and other socio-economic variables have intensified the vulnerability of these communities to the impacts of malaria.  相似文献