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1.
J Adv Model Earth Syst ; 14(6): e2021MS002852, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35864944

RESUMO

The NASA Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) provides recent estimates and 5-day forecasts of atmospheric composition to the public in near-real time. To do this, the GEOS Earth system model is coupled with the GEOS-Chem tropospheric-stratospheric unified chemistry extension (UCX) to represent composition from the surface to the top of the GEOS atmosphere (0.01 hPa). The GEOS-CF system is described, including updates made to the GEOS-Chem UCX mechanism within GEOS-CF for improved representation of stratospheric chemistry. Comparisons are made against balloon, lidar, and satellite observations for stratospheric composition, including measurements of ozone (O3) and important nitrogen and chlorine species related to stratospheric O3 recovery. The GEOS-CF nudges the stratospheric O3 toward the GEOS Forward Processing (GEOS FP) assimilated O3 product; as a result the stratospheric O3 in the GEOS-CF historical estimate agrees well with observations. During abnormal dynamical and chemical environments such as the 2020 polar vortexes, the GEOS-CF O3 forecasts are more realistic than GEOS FP O3 forecasts because of the inclusion of the complex GEOS-Chem UCX stratospheric chemistry. Overall, the spatial patterns of the GEOS-CF simulated concentrations of stratospheric composition agree well with satellite observations. However, there are notable biases-such as low NO x and HNO3 in the polar regions and generally low HCl throughout the stratosphere-and future improvements to the chemistry mechanism and emissions are discussed. GEOS-CF is a new tool for the research community and instrument teams observing trace gases in the stratosphere and troposphere, providing near-real-time three-dimensional gridded information on atmospheric composition.

2.
Q J R Meteorol Soc ; 143(707): 2481-2495, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29760535

RESUMO

In this study, gravity waves (GWs) in the high-resolution GEOS-5 Nature Run are first evaluated with respect to satellite and other model results. Southern Hemisphere winter sources of non-orographic GWs in the model are then investigated by linking measures of tropospheric non-orographic gravity wave generation tied to precipitation and frontogenesis with absolute gravity wave momentum flux in the lower stratosphere. Finally, non-orographic GW momentum flux is compared to orographic gravity wave momentum flux and compared to previous estimates. The results show that the global patterns in GW amplitude, horizontal wavelength, and propagation direction are realistic compared to observations. However, as in other global models, the amplitudes are weaker and horizontal wavelengths longer than observed. The global patterns in absolute GW momentum flux also agree well with previous model and observational estimates. The evaluation of model non-orographic GW sources in the Southern Hemisphere winter shows that strong intermittent precipitation (greater than 10 mm h-1) is associated with GW momentum flux over the South Pacific, whereas frontogenesis and less intermittent, lower precipitation rates (less than 10 mm h-1) are associated with GW momentum flux near 60°S. In the model, orographic GWs contribute almost exclusively to a peak in zonal mean momentum flux between 70 and 75°S, while non-orographic waves dominate at 60°S, and non-orographic GWs contribute a third to a peak in zonal mean momentum flux between 25 and 30°S.

3.
J Econ Entomol ; 109(1): 232-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26476555

RESUMO

Two saproxylic forest insects, Hylurgus ligniperda (F.) (Coleoptera: Scolytinae) and Arhopalus ferus (Mulsant)(Coleoptera: Cerambycidae), were reared on artificial or natural diet at 15 or 25°C to compare larval growth rates and survival. A significant diet by temperature interaction was observed in the growth of H. ligniperda larvae,which developed faster when reared on natural diet at 15°C, but grew faster and pupated significantly earlier when reared on artificial diet at 25°C. However, H. ligniperda survival by the end of the experiment was low on both diets when reared at 25°C (10.1%, 95% CI: 5.2­15.1%), which suggests that rearing at lower temperatures may be required. A. ferus larvae gained significantly larger body size when reared on artificial diet than on natural diet at both temperatures. Survival of A. ferus reared on artificial diet was significantly lower than larvae reared on natural diet at 25°C. The significant differences between A. ferus larval development rates when reared on artificial and natural diets preclude the use of artificial diet to collect meaningful data to construct temperature development models for ecological comparisons. Artificial diet provided a suitable medium for mass production of individuals for research purposes, e.g., test mortality in response to treatments. However, additional rearing studies are needed to determine whether the larger artificially reared larvae result in adults that are healthier, more productive, and live longer.


Assuntos
Besouros/fisiologia , Ração Animal/análise , Animais , Besouros/crescimento & desenvolvimento , Dieta , Controle de Insetos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Gorgulhos/crescimento & desenvolvimento , Gorgulhos/fisiologia
4.
J Geophys Res Atmos ; 121(13): 8067-8082, 2016 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-29593948

RESUMO

Satellite instruments show a cooling of global stratospheric temperatures over the whole data record (1979-2014). This cooling is not linear, and includes two descending steps in the early 1980s and mid-1990s. The 1979-1995 period is characterized by increasing concentrations of ozone depleting substances (ODS) and by the two major volcanic eruptions of El Chichón (1982) and Mount Pinatubo (1991). The 1995-present period is characterized by decreasing ODS concentrations and by the absence of major volcanic eruptions. Greenhouse gas (GHG) concentrations increase over the whole time period. In order to isolate the roles of different forcing agents in the global stratospheric temperature changes, we performed a set of AMIP-style simulations using the NASA Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). We find that in our model simulations the cooling of the stratosphere from 1979 to present is mostly driven by changes in GHG concentrations in the middle and upper stratosphere and by GHG and ODS changes in the lower stratosphere. While the cooling trend caused by increasing GHGs is roughly constant over the satellite era, changing ODS concentrations cause a significant stratospheric cooling only up to the mid-1990s, when they start to decrease because of the implementation of the Montreal Protocol. Sporadic volcanic events and the solar cycle have a distinct signature in the time series of stratospheric temperature anomalies but do not play a statistically significant role in the long-term trends from 1979 to 2014. Several factors combine to produce the step-like behavior in the stratospheric temperatures: in the lower stratosphere, the flattening starting in the mid 1990's is due to the decrease in ozone depleting substances; Mount Pinatubo and the solar cycle cause the abrupt steps through the aerosol-associated warming and the volcanically induced ozone depletion. In the middle and upper stratosphere, changes in solar irradiance are largely responsible for the step-like behavior of global temperatures anomalies, together with volcanically induced ozone depletion and water vapor increases in the post-Pinatubo years.

5.
Ecol Appl ; 24(7): 1561-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-29210222

RESUMO

Recognition of the extent and magnitude of night-time light pollution impacts on natural ecosystems is increasing, with pervasive effects observed in both nocturnal and diurnal species. Municipal and industrial lighting is on the cusp of a step change where energy-efficient lighting technology is driving a shift from "yellow" high-pressure sodium vapor lamps (HPS) to new "white" light-emitting diodes (LEDs). We hypothesized that white LEDs would be more attractive and thus have greater ecological impacts than HPS due to the peak UV-green-blue visual sensitivity of nocturnal invertebrates. Our results support this hypothesis; on average LED light traps captured 48% more insects than were captured with light traps fitted with HPS lamps, and this effect was dependent on air temperature (significant light × air temperature interaction). We found no evidence that manipulating the color temperature of white LEDs would minimize the ecological impacts of the adoption of white LED lights. As such, large-scale adoption of energy-efficient white LED lighting for municipal and industrial use may exacerbate ecological impacts and potentially amplify phytosanitary pest infestations. Our findings highlight the urgent need for collaborative research between ecologists and electrical engineers to ensure that future developments in LED technology minimize their potential ecological effects.


Assuntos
Cor , Poluição Ambiental , Luz/efeitos adversos , Iluminação , Animais , Biodiversidade , Cidades , Conservação dos Recursos Naturais , Meio Ambiente
6.
J Econ Entomol ; 102(1): 79-85, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19253621

RESUMO

Several longhorn beetles (Cerambycidae) and bark beetles (Scolytinae) have been accidentally introduced to New Zealand and are now widespread and abundant. In particular Arhopalus ferus (Mulsant) represents a significant quarantine risk for export timber. Because of this risk timber is fumigated with methyl bromide. Six different light traps baited with different colors (yellow, red, green, white, UV-black light [UV-BL], and UV-black-light-blue [UV-BLB]) were investigated for their population monitoring potential and as a push-pull (incorporating mass trapping) alternative control technique. UV-BLB light traps captured an order of magnitude more A. ferus (122 individuals per night) than yellow light traps (eight individuals per night). The bark beetles Hylurgus ligniperda (F.) and Hylastes ater (Paykull) were most attracted to UV-BL lights that captured 2-4 times more beetles than traps baited with other wavelengths. Results suggest that light traps provide a sensitive method for population monitoring. The responses of these wood borers and bark beetles to different colored light traps provide an opportunity to apply a push-pull control technique. The management of these species could be improved by minimizing the visual attractiveness (push) of wood processing facilities through a conversion to low intensity yellow site lighting, combined with the strategic placement of UV light traps for mass-trapping of residual populations (pull). Light management on its own is unlikely to eliminate the quarantine risk entirely; however, it is likely to reduce populations substantially and contribute toward the aim of reducing methyl bromide use.


Assuntos
Comportamento Apetitivo/efeitos da radiação , Besouros/efeitos da radiação , Controle de Insetos/métodos , Luz , Animais , Madeira/parasitologia
7.
Science ; 320(5882): 1486-9, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18556557

RESUMO

In the past several decades, the tropospheric westerly winds in the Southern Hemisphere have been observed to accelerate on the poleward side of the surface wind maximum. This has been attributed to the combined anthropogenic effects of increasing greenhouse gases and decreasing stratospheric ozone and is predicted to continue by the Intergovernmental Panel on Climate Change/Fourth Assessment Report (IPCC/AR4) models. In this paper, the predictions of the Chemistry-Climate Model Validation (CCMVal) models are examined: Unlike the AR4 models, the CCMVal models have a fully interactive stratospheric chemistry. Owing to the expected disappearance of the ozone hole in the first half of the 21st century, the CCMVal models predict that the tropospheric westerlies in Southern Hemisphere summer will be decelerated, on the poleward side, in contrast with the prediction of most IPCC/AR4 models.

9.
Biochem J ; 180(1): 195-9, 1979 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-226065

RESUMO

Feeding rats with sorbitol, fructose, glycerol and ethanol increases the concentration of serum corticosterone without significantly altering the concentration of insulin. This increase appears to be partly responsible for the increases in the hepatic activity of phosphatidate phosphohydrolase (compared with rats fed glucose or 0.9% NaCl) that has been reported [Sturton, Pritchard, Han & Brindley (1978) Biochem. J. 174, 667--670] and the enhanced capacity of the liver to synthesize triacylglycerols. The ethanol-induced increase in phosphohydrolase activity was largely, but not completely, prevented by adrenalectomy.


Assuntos
Corticosterona/sangue , Fígado/metabolismo , Fosfatidato Fosfatase/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Triglicerídeos/biossíntese , Animais , Etanol/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Glicerol/metabolismo , Insulina/sangue , Ratos , Sorbitol/metabolismo
12.
J Natl Cancer Inst ; 54(4): 829-34, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1168727

RESUMO

Biologic and physiologic factors associated with the availability of breast secretions by a nipple aspiration technique were investigated in 606 normal, non-lactating women. Data obtained on race, age, menstrual status, parity, contraceptive pill use, hormone use, and cerumen type indicated that availability of secretions was related to race, age, and menopause, and to genetic factors associated with apocrine bland function. Fluid aspirates were obtained most often from Caucasians (70.2% success), least often from Chinese (24.1% success). The percentage of successful aspirations declined in women over 50 years of age in all racial groups, but distinctly less so in Caucasians. Chinese and Japanese women with dry-type cerumen had a lower percentage of successful aspirations than those with wet type, which suggested that genetic factors may be associated with breast fluid secretion in nonlactating women.


Assuntos
Fatores Etários , Mama/metabolismo , Menopausa , Grupos Raciais , População Negra , Doenças Mamárias/fisiopatologia , Cerume , China/etnologia , Anticoncepcionais Orais , Drenagem , Estrogênios/uso terapêutico , Feminino , Humanos , Japão/etnologia , Lactação , Mastectomia , México/etnologia , Paridade , Filipinas/etnologia , Gravidez , Estados Unidos , População Branca
13.
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