269 research outputs found
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Southern Hemisphere Cloud–Dynamics Biases in CMIP5 Models and Their Implications for Climate Projections
This study quantifies cloud–radiative anomalies associated with interannual variability in the latitude of the Southern Hemisphere (SH) midlatitude eddy-driven jet, in 20 global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5). Two distinct model types are found. In the first class of models (type I models), total cloud fraction is reduced at SH midlatitudes as the jet moves poleward, contributing to enhanced shortwave radiative warming. In the second class of models (type II models), this dynamically induced cloud radiative warming effect is largely absent. Type I and type II models have distinct deficiencies in their representation of observed Southern Ocean clouds, but comparison with two independent satellite datasets indicates that the cloud–dynamics behavior of type II models is more realistic.
Because the SH midlatitude jet shifts poleward in response to CO₂ forcing, the cloud–dynamics biases uncovered from interannual variability are directly relevant for climate change projections. In CMIP5 model experiments with abruptly quadrupled atmospheric CO₂ concentrations, the global-mean surface temperature initially warms more in type I models, even though their equilibrium climate sensitivity is not significantly larger. In type I models, this larger initial warming is linked to the rapid adjustment of the circulation and clouds to CO₂ forcing in the SH, where a nearly instantaneous poleward shift of the midlatitude jet is accompanied by a reduction in the reflection of solar radiation by clouds. In type II models, the SH jet also shifts rapidly poleward with CO₂ quadrupling, but it is not accompanied by cloud radiative warming anomalies, resulting in a smaller initial global-mean surface temperature warming
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The response midlatitude jets to increased CO2: Distinguishing the roles of sea surface temperature and direct radiative forcing
In Coupled Model Intercomparison Project Phase 5 (CMIP5) models, the zonal-mean tropospheric circulation shifts robustly poleward in the Southern Hemisphere extratropics in response to increased atmospheric CO₂ concentrations. However, in the Northern Hemisphere (NH) extratropics, the circulation response to CO₂ is largely absent in the zonal mean and is instead characterized by complex regional anomalies. This study decomposes the atmospheric circulation response to CO₂ forcing in CMIP5 models into two components: a direct component due to CO₂ radiative forcing and an indirect component associated with sea surface temperature (SST)-mediated changes. The direct radiative forcing of CO₂ drives a weak poleward jet shift in both hemispheres, whereas the indirect (SST) component of the CO₂ forcing dominates the total response and drives a zonally asymmetric response in the NH. Hence, understanding the SST-mediated component of atmospheric CO₂ forcing appears crucial to unlocking the mechanisms that contribute to forced extratropical circulation changes
Searching for X-ray sources in nearby late-type galaxies with low star formation rates
Late type non-starburst galaxies have been shown to contain X-ray emitting
objects, some being ultraluminous X-ray sources. We report on XMM-Newton
observations of 11 nearby, late-type galaxies previously observed with the
Hubble Space Telescope (HST) in order to find such objects. We found 18 X-ray
sources in or near the optical extent of the galaxies, most being point-like.
If associated with the corresponding galaxies, the source luminosities range
from erg s to erg s. We
found one ultraluminous X-ray source, which is in the galaxy IC 5052, and one
source coincident with the galaxy IC 4662 with a blackbody temperature of
keV that could be a quasi-soft source or a quiescent neutron
star X-ray binary in the Milky Way. One X-ray source, XMMU J205206.0691316,
is extended and coincident with a galaxy cluster visible on an HST image. The
X-ray spectrum of the cluster reveals a redshift of and a
temperature of 3.60.4 keV. The redshift was mainly determined by a cluster
of Fe XXIV lines between the observed energy range keV.Comment: 8 pages, to appear in MNRA
Chain Community Pharmacists\u27 Willingness, Attitudes, and Barriers in Providing Self-Care Medication and Supplement Recommendations
BACKGROUND: Pharmacists are commonly called on as the first resource for patients when selecting an appropriate self-care medication or supplement. This study examines pharmacists’ over-the-counter (OTC) recommendations in the chain community pharmacy setting in the United States. OBJECTIVES: The objective of the study was to assess chain community pharmacists’ willingness and attitudes to provide self-care recommendations to patients and to identify chain community pharmacists’ barriers to making OTC medication and supplement recommendations. METHODS: An anonymous survey was created to identify pharmacists’ attitudes and their willingness to perform these recommendations. The questionnaire included specific questions to identify barriers that exist to making OTC recommendations. The survey was distributed by fax and email to 527 pharmacists in the Mid-South regional district of a U.S. grocery chain pharmacy. Descriptive statistics were used to identify demographic trends and display results. RESULTS: Pharmacists are overwhelmingly willing to provide OTC recommendations (100%) and see it as an important part of community practice (99%). The greatest barriers were time/prescription volume (94%) and staffing demands (78%). The greatest need for education was in the areas of eye/ear care and vitamins/herbal products. CONCLUSIONS: The results affirmed pharmacists’ willingness and overall positive attitude to providing OTC medication counseling in the community pharmacy setting. The research uniquely identified barriers that pharmacists experience when attempting to make OTC recommendations. This information can be used not only for the implementation of patient care services targeting self-care needs but also in the application of general community pharmacy practice
The Ozone Hole Indirect Effect: Cloud-Radiative Anomalies Accompanying the Poleward Shift of the Eddy-Driven Jet in the Southern Hemisphere
This study quantifies the response of the clouds and the radiative budget of the Southern Hemisphere (SH) to the poleward shift in the tropospheric circulation induced by the development of the Antarctic ozone hole. Single forcing climate model integrations, in which only stratospheric ozone depletion is specified, indicate that (1) high-level and midlevel clouds closely follow the poleward shift in the SH midlatitude jet and that (2) low-level clouds decrease across most of the Southern Ocean. Similar cloud anomalies are found in satellite observations during periods when the jet is anomalously poleward. The hemispheric annual mean radiation response to the cloud anomalies is calculated to be approximately +0.25 W m−2, arising largely from the reduction of the total cloud fraction at SH midlatitudes during austral summer. While these dynamically induced cloud and radiation anomalies are considerable and are supported by observational evidence, quantitative uncertainties remain from model biases in mean-state cloud-radiative processes
Diagnóstico e modelagem da integração lavoura-pecuária na Região de Paragominas, PA.
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Is climate sensitivity related to dynamical sensitivity? A Southern Hemisphere perspective
This study examines whether the spread in the climate sensitivity of Coupled Model Intercomparison Project Phase 5 (CMIP5) models also captures the spread in the Southern Hemisphere dynamical response to greenhouse gas forcing. Three metrics are proposed to quantify the “dynamical sensitivity” of the Southern Hemisphere: the poleward expansion of the Hadley circulation, the poleward expansion of the subtropical dry zone, and the poleward shift of the midlatitude jet. In the CMIP5 abrupt 4 × CO₂ integrations, the expansion of the Hadley circulation is well correlated with climate sensitivity in all seasons; in contrast, the shifts in the subtropical dry zone and midlatitude jet are significantly correlated with climate sensitivity only in summer and fall. In winter, those responses are more strongly linked to the control climatology in each model. Thus, a narrow focus on traditional climate sensitivity alone might miss out on important features of the atmospheric circulation's response to increasing greenhouse gases, particularly in the extratropics
TT ILPF - construindo capacidades e inovando no setor produtivo do Tocantins e sul do Pará.
A pesquisa brasileira e, em especial, a Embrapa, passou a desenvolver tecnologias mais conservacionistas e, nesse sentido, a integração lavoura-pecuária-floresta (ILPF) vem sendo trabalhada pela empresa em todo o país como uma inovação para a produção agropecuária sustentável. Este sistema permite a produção concomitante de árvores, grãos, forragem e atividade pecuária em áreas anteriormente de monocultivo, e possibilita a recuperação das áreas de pastagens degradadas via consórcio, sucessão e/ou rotação. O sistema ILPF permite aumento da matéria orgânica e atividade biológica do solo, bem como, redução das emissões de gases do efeito estufa, promovendo a sustentabilidade produtiva das áreas. Além disso, a ILPF propicia ganhos econômicos, estabilidade da renda do produtor na medida em que permite maior oferta de emprego e produção o ano todo (grãos, carne, leite, energia, produtos madeireiros e não madeireiros oriundos das árvores). Em função de todas estas características técnicas, econômicas e sociais do sistema, a adoção de ILPF promove uma maneira inovadora de produção de alimentos, fibras e energia.bitstream/item/205777/1/CNPASA-2019-cap10.pd
Emissão de metano do solo em pastagens no município de Paragominas, Nordeste do Estado do Pará.
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