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41.
Kristie L. Ebi Elisabet Lindgren Jonathan E. Suk Jan C. Semenza 《Climatic change》2013,118(2):355-365
Climate change has the potential to increase the challenge of preventing and controlling outbreaks of infectious diseases. An adaptation assessment is an important aspect of designing and implementing policies and measures to avoid, prepare for, and effectively respond to infectious diseases outbreaks. The main steps in conducting an adaptation assessment include: 1) evaluating the effectiveness of policies and measures that address the burden of climate-sensitive infectious diseases; 2) identifying options to manage the health risks of current and projected climate change; 3) evaluating and prioritizing the options; 4) identifying human and financial resources needs, and possible barriers, constraints, and limits to implementation; and 5) developing monitoring and evaluation programs to ensure continued effectiveness of policies and measures in a changing climate. Optimally, relevant stakeholders are optimally included throughout the adaptation assessment. Although the process of conducting an assessment is similar across nations and regions, the context and content will vary depending on local circumstances, socioeconomic conditions, legal and regulatory frameworks, and other factors. The European Centers for Disease Prevention and Control developed guidelines for conducting assessments, with sufficient consistency to facilitate learning lessons across assessments. 相似文献
42.
Chris Turney Mike Baillie Steve Clemens David Brown Jonathan Palmer Jonathan Pilcher Paula Reimer Hanns Hubert Leuschner 《第四纪科学杂志》2005,20(6):511-518
The temporal and spatial extent of Holocene climate change is an area of considerable uncertainty, with solar forcing recently proposed to be the origin of cycles identified in the North Atlantic region. To address these issues we have developed an annually resolved record of changes in Irish bog tree populations over the last 7468 years which, together with radiocarbon‐dated bog and lake‐edge populations, extend the dataset back to ~9000 yr ago. The Irish trees underpin the internationally accepted radiocarbon calibration curve, used to derive a proxy of solar activity, and allow us to test solar forcing of Holocene climate change. Tree populations and age structures provide unambiguous evidence of major shifts in Holocene surface moisture, with a dominant cyclicity of 800 yr, similar to marine cycles in the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. The cycles, however, are not coherent with changes in solar activity (both being on the same absolute timescale), indicating that Holocene North Atlantic climate variability at the millennial and centennial scale is not driven by a linear response to changes in solar activity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
43.
Se i resonance lines have been measured in absorption to an accuracy of a few milliång-stroms by using the flash photolysis technique. As a result it was found that the 4p
3nl levels and the ionization limit given by Morillon and Vergès should be increased by 0.23 ± 0.02 cm–1. Calculated wavelengths are given for Se i lines which may be searched for in the solar spectrum in order to find selenium in the Sun. 相似文献
44.
Ilhem Bentaleb Cyril Langlois Céline Martin Paula Iacumin Matthieu Carré Pierre-Olivier Antoine Francis Duranthon Issam Moussa Jean-Jacques Jaeger Nicholas Barrett Ron Kandorp 《Comptes Rendus Geoscience》2006,338(3):172-179
The relationship between the oxygen isotope ratio of mammal tooth enamel and that of drinking water was used to reconstruct changes in the Miocene oxygen isotope ratio of rainfall (meteoric water OMW). These, in turn, are related to climatic parameters (temperature, precipitation and evaporation rate). O values of rhinocerotid teeth from the Aquitaine Basin (southwestern France) suggest a significant climatic change between 17 and 12 Ma, characterized by cooling together with precipitation increase, in agreement with other terrestrial and oceanic records. To cite this article: I. Bentaleb et al., C. R. Geoscience 338 (2006). 相似文献
45.
Giovana M. de Espindola Ana Paula D. de AguiarEdzer Pebesma Gilberto CâmaraLeila Fonseca 《Applied geography (Sevenoaks, England)》2012,32(2):240-252
The potential impact of deforestation in the Brazilian Amazon on greenhouse gas emissions to the atmosphere calls for policies that take account of changes in forest cover. Although much research has focused on the location and effects of deforestation, little is known about the distribution and reasons for the agricultural uses that replace forest cover. We used Landsat TM-based deforestation and agricultural census data to generate maps of the distribution and proportion of four major agricultural land uses throughout the Brazilian Amazon in 1997 and 2007. We built linear and spatial regression models to assess the determinant factors of deforestation and those major agricultural land uses - pasture, temporary agriculture and permanent agriculture - for the states of Pará, Rondônia, and Mato Grosso. The data include 30 determinant factors that were grouped into two years (1996 and 2006) and in four categories: accessibility to markets, public policies, agrarian structure, and environment. We found an overall expansion of the total agricultural area between 1997 and 2007, and notable differences between the states of Pará, Rondônia, and Mato Grosso in land use changes during this period. Regression models for deforestation and pasture indicated that determinant factors such as distance to roads were more influential in 1997 than in 2007. The number of settled families played an important role in the deforestation and pasture, the effect was stronger in 2007 than 1997. Indigenous lands were significant in preventing deforestation in high-pressure areas in 2007. For temporary and permanent agricultures, our results show that in 1997 the effect of small farms was stronger than in 2007. The mapped land use time series and the models explain empirically the effects of land use changes across the region over one decade. 相似文献
46.
Previous studies have shown that Regional Climate Models (RCM) internal variability (IV) fluctuates in time depending on synoptic events. This study focuses on the physical understanding of episodes with rapid growth of IV. An ensemble of 21 simulations, differing only in their initial conditions, was run over North America using version 5 of the Canadian RCM (CRCM). The IV is quantified in terms of energy of CRCM perturbations with respect to a reference simulation. The working hypothesis is that IV is arising through rapidly growing perturbations developed in dynamically unstable regions. If indeed IV is triggered by the growth of unstable perturbations, a large proportion of the CRCM perturbations must project onto the most unstable singular vectors (SVs). A set of ten SVs was computed to identify the orthogonal set of perturbations that provide the maximum growth with respect to the dry total-energy norm during the course of the CRCM ensemble of simulations. CRCM perturbations were then projected onto the subspace of SVs. The analysis of one episode of rapid growth of IV is presented in detail. It is shown that a large part of the IV growth is explained by initially small-amplitude unstable perturbations represented by the ten leading SVs, the SV subspace accounting for over 70% of the CRCM IV growth in 36?h. The projection on the leading SV at final time is greater than the projection on the remaining SVs and there is a high similarity between the CRCM perturbations and the leading SV after 24–36?h tangent-linear model integration. The vertical structure of perturbations revealed that the baroclinic conversion is the dominant process in IV growth for this particular episode. 相似文献
47.
J.-F. Miao D. Chen K. Wyser K. Borne J. Lindgren M. K. S. Strandevall S. Thorsson C. Achberger E. Almkvist 《Meteorology and Atmospheric Physics》2008,99(1-2):77-103
Summary The performance of MM5 mesoscale model (Version 3.6.3) using different planetary boundary layer (PBL) and land surface model
(LSM) parameterizations is evaluated and compared using high temporal and spatial resolution G?TE2001 campaign data at local
scale (a few kilometers) over the Greater G?teborg area along the Swedish west coast during 7–20 May 2001. The focus is on
impact of PBL and LSM parameterizations on simulated meteorological variables important for air quality applications such
as global radiation, diurnal cycle of near-surface air temperature and wind, diurnal cycle intensity, near-surface vertical
temperature gradient, nocturnal temperature inversion, boundary layer height, and low-level jet (LLJ). The model performance
for daytime and nighttime and under different weather conditions is also discussed. The purpose is to examine the performance
of the model using different PBL and LSM parameterizations at local scale in this area for its potential applications in air
quality modeling. The results indicate that the influence of PBL and LSM parameterizations on simulated global radiation,
diurnal cycle of near-surface air temperature and wind speed, diurnal cycle intensity, vertical temperature gradient, nocturnal
temperature inversion and PBL heights, which are critical parameters for air quality applications, is evident. Moreover, the
intensity and location of LLJ are simulated well by all schemes, but there also exist some differences between simulated results
by using different PBL and LSM schemes. Therefore, the choice of PBL and LSM parameterizations is important for MM5 applications
to air quality studies.
Correspondence: Junfeng Miao, Department of Earth Sciences, G?teborg University, P.O. Box 460, 405 30 G?teborg, Sweden 相似文献
48.
Salles Lucas A. Vani Bruno C. Moraes Alison Costa Emanoel de Paula Eurico R. 《Surveys in Geophysics》2021,42(4):999-1025
Surveys in Geophysics - Over the last 15 years, the satellite constellation of the global positioning system (GPS) has been modernized for more precise applications, with the introduction... 相似文献
49.
Bissiri Pier Giovanni Peron Ana Paula Porcu Emilio 《Stochastic Environmental Research and Risk Assessment (SERRA)》2020,34(5):723-732
Stochastic Environmental Research and Risk Assessment - Axial symmetry for covariance functions defined over spheres has been a very popular assumption for climate, atmospheric, and environmental... 相似文献
50.
Ugur Kagan Tekin Cengiz Okuyucu Kaan Sayit Yavuz Bedi Paula J. Noble Leopold Krystyn Mehmet Cemal Gncüoglu 《Island Arc》2019,28(2)
Blocks and tectonic slices within the Mersin Mélange (southern Turkey), which are of Northern Neotethyan origin (Izmir–Ankara–Erzincan Ocean (IAE)), were studied in detail by using radiolarian, conodont, and foraminiferal assemblages on six different stratigraphic sections with well‐preserved Permian succesions. The basal part of the Permian sequence, composed of alternating chert and mudstone with basic volcanics, is assigned to the late Asselian (Early Permian) based on radiolarians. The next basaltic interval in the sequence is dated as Kungurian. The highly alkaline basic volcanics in the sequence are extremely enriched, similar to kimberlitic/lamprophyric magmas generated at continental intraplate settings. Trace element systematics suggest that these lavas were generated in a continental margin involving a metasomatized subcontinental lithospheric mantle source (SCLM). The middle part of the Permian sequences, dated by benthic foraminifera and conodont assemblages, includes detrital limestones with chert interlayers and neptunian dykes of middle Wordian to earliest Wuchiapingian age. Higher in the sequence, detrital limestones are overlain by alternating chert and mudstone with intermittent microbrecciated beds of early Wuchiapingian to middle Changhsingian (Late Permian) age based on the radiolarians. A large negative shift at the base of the Lopingian at the upper part of section is correlated to negative shifts at the Guadalupian/Lopingian boundary associated with the end‐Guadalupian mass extinction event. All these findings indicate that a continental rift system associated with a possible mantle plume existed during the late Early to Late Permian period. This event was responsible for the rupturing of the northern Gondwanan margin related to the opening of the IAE Ocean. When the deep basinal features of the Early Permian volcano‐sedimentary sequence are considered, the proto IAE oceanic crust formed possibly before the end of the Permian. This, in turn, suggests that the opening of the IAE Ocean dates back to as early as the Permian. 相似文献