Do people “personally experience” global warming,and if so how,and does it matter?   总被引：1，自引：0，他引：1  

Karen Akerlof  Edward W. Maibach  Dennis Fitzgerald  Andrew Y. Cedeno  Amanda Neuman 《Global Environmental Change》2013,23(1):81-91

For most people, the direct and personally observable signals of climate change should be difficult to detect amid the variability of everyday weather. Yet, previous research has shown that some people believe they have personally experienced global warming. Through four related studies, our paper sheds light on what signals of global warming some people believe they are detecting, why, and whether or not it matters. These studies were conducted using population survey and climatic data from a single county in Michigan. Study 1 found that 27% of the county's adult residents felt that they had personally experienced global warming. Study 2 – based on content analysis of people's open-ended responses – found that the most frequently described personal experiences of global warming were changes in seasons (36%), weather (25%), lake levels (24%), animals and plants (20%), and snowfall (19%). Study 3 – based on NOAA climatic data – found that most, but not all, of these detected signals are borne out in the climatic record. Study 4 – using the survey data – found that personal experience of global warming matters in that it predicts perceptions of local risk of global warming, controlling for demographics, political affiliation, and cultural beliefs about national policy outcomes. We conclude that perceived personal experience of global warming appears to heighten people's perception of the risks, likely through some combination of direct experience, vicarious experience (e.g., news media stories), and social construction.  相似文献   

A high-resolution infrared spectral survey of Comet C/1999 H1 Lee     

Neil Dello Russo  Michael J. Mumma  Karen Magee-Sauer  Boncho P. Bonev  I.S. McLean 《Icarus》2006,184(1):255-276

We obtained high-resolution (λ/Δλ∼25,000) spectra of Comet C/1999 H1 (Lee) on UT 1999 August 19.6 and 21.6 using the cross-dispersed Near InfraRed SPECtrometer (NIRSPEC) at the Keck Observatory atop Mauna Kea, HI. Here we present spectra of Comet Lee between 2.874 and 3.701 μm (3479-2702 cm⁻¹) representing the most complete high-resolution infrared survey of a comet to date in this wavelength region. Using published line lists and laboratory spectra we have identified 444 of the 545 distinct emission features present in these spectra. We have tabulated the rest frequencies, assignments, relative intensities, and signal-to-noise ratios of all detected emissions. In addition to gaining insights into the chemistry of Comet Lee, this survey provides a valuable tool for planning future high-resolution infrared observations of comets and other astronomical targets, and for retrospective comparison to existing high-resolution infrared datasets.  相似文献   

Response of surface water chemistry to reduced levels of acid precipitation: comparison of trends in two regions of New York,USA     

Douglas A. Burns  Michael R. McHale  Charles T. Driscoll  Karen M. Roy 《水文研究》2006,20(7):1611-1627

In light of recent reductions in sulphur (S) and nitrogen (N) emissions mandated by Title IV of the Clean Air Act Amendments of 1990, temporal trends and trend coherence in precipitation (1984–2001 and 1992–2001) and surface water chemistry (1992–2001) were determined in two of the most acid‐sensitive regions of North America, i.e. the Catskill and Adirondack Mountains of New York. Precipitation chemistry data from six sites located near these regions showed decreasing sulphate (SO₄^2?), nitrate (NO₃^?), and base cation (C_B) concentrations and increasing pH during 1984–2001, but few significant trends during 1992–2001. Data from five Catskill streams and 12 Adirondack lakes showed decreasing trends in SO₄^2? concentrations at all sites, and decreasing trends in NO₃^?, C_B, and H⁺ concentrations and increasing trends in dissolved organic carbon at most sites. In contrast, acid‐neutralizing capacity (ANC) increased significantly at only about half the Adirondack lakes and in one of the Catskill streams. Flow correction prior to trend analysis did not change any trend directions and had little effect on SO₄^2? trends, but it caused several significant non‐flow‐corrected trends in NO₃^? and ANC to become non‐significant, suggesting that trend results for flow‐sensitive constituents are affected by flow‐related climate variation. SO₄^2? concentrations showed high temporal coherence in precipitation, surface waters, and in precipitation–surface water comparisons, reflecting a strong link between S emissions, precipitation SO₄^2? concentrations, and the processes that affect S cycling within these regions. NO₃^? and H⁺ concentrations and ANC generally showed weak coherence, especially in surface waters and in precipitation–surface water comparisons, indicating that variation in local‐scale processes driven by factors such as climate are affecting trends in acid–base chemistry in these two regions. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

Multiwavelength focusing with the Sun as gravitational lens     

Laurent Koechlin  Denis Serre  Gerald K. Skinner  Peter Von Ballmoos  Thomas Crouzil 《Experimental Astronomy》2005,20(1-3):307-315

The light deviation caused by the gravitational potential in the vicinity of the sun could be used as a means of focussing radiation that cannot be focussed easily otherwise. The gravitational lens formed by the sun is not stigmatic, but does have the advantage of being achromatic and acts identically on all types of mass-less radiations. For a source at infinity, its geometrical characteristics present a “caustic” line starting at 550 astronomical units (UA) downstream from the sun. In a plane perpendicular to that caustic line, images of distant objects are formed.The perturbations by the solar corona plasma will significantly blur electromagnetic radiation for wavelengths longer than those of the IR domain. At shorter wavelengths, for example the γ domain, the focussing process could lead to 10⁸ amplification factors. In order to reach the regions where images are formed, long distance space missions are necessary. Once launched, missions of this type would be dedicated to a single field. Some possible targets are considered, such as Sagitarius A observed in X and γ rays.In this paper we study the point spread function (PSF) of the sun as a gravitational lens. Taking into account perturbations by the planets, the non sphericity of the sun and coronal plasma index, we derive limits within which such observations could be possible.  相似文献   

Neutral gas composition measurements between 80 and 120 km     

D. Offermann  V. Friedrich  P. Ross  U. Von Zahn 《Planetary and Space Science》1981,29(7):747-764

Atmospheric composition in the turbopause regime was determined by four rocket-borne mass spectrometers, which employed shock-freezing cryo-ion sources. Number densities of N₂, O₂, O, Ar and CO₂ are presented for these experiments. The results are compared with those of other rocket experiments taken from the literature. Ar/N₂ ratios are analyzed with respect to atmospheric turbulence. Magnitude and variability of atomic oxygen layer maximum density and layer content are discussed. Variations of O densities and simultaneous Ar/N₂ ratio changes are compared. Six CO₂ measurements are discussed in terms of CO₂/N₂ ratios.  相似文献   

Historical Climatology In Europe – The State Of The Art     

Rudolf?BráZdilEmail author  Christian?Pfister  Heinz?Wanner  Hans?Von?Storch  JüRg?Luterbacher 《Climatic change》2005,70(3):363-430

This paper discusses the state of European research in historical climatology. This field of science and an overview of its development are described in detail. Special attention is given to the documentary evidence used for data sources, including its drawbacks and advantages. Further, methods and significant results of historical-climatological research, mainly achieved since 1990, are presented. The main focus concentrates on data, methods, definitions of the “Medieval Warm Period” and the “Little Ice Age”, synoptic interpretation of past climates, climatic anomalies and natural disasters, and the vulnerability of economies and societies to climate as well as images and social representations of past weather and climate. The potential of historical climatology for climate modelling research is discussed briefly. Research perspectives in historical climatology are formulated with reference to data, methods, interdisciplinarity and impacts.  相似文献   

A geochemical record of the mining history of the Erme Estuary, south Devon, UK     

Price GD  Winkle K  Gehrels WR 《Marine pollution bulletin》2005,50(12):1706-1712

The concentration of selected trace metals (Cu, Pb and Zn) in salt-marsh sediments from within the Erme Estuary have been measured in order to assess possible historical sources of pollution. The Erme Estuary, south Devon, UK is an Area of Outstanding Natural Beauty and has remained largely unaffected by industrialisation, although a number of small silver–lead mines were in operation in the 1800s. Five cores reveal comparable geochemical profiles. An increase of lead at 40 cm depth is observed, reaching maximum values of 427 ppm. Less distinct trends are revealed by zinc and copper, probably reflecting the lack of widespread mining for ores of these elements within the catchment and possible post-depositional mobility rendering the metal concentrations non-contemporaneous with the chemostratigraphy of lead. The geochemical analysis of the salt-marsh sediments provides a fairly robust chemostratigraphic scheme and the likely sources of mine waste can be pinpointed within the catchment. Based upon reference to the historical mining record of these mines chemostratigraphic dating of the sediments can be achieved in order to provide an estimate of salt-marsh accretion rates and sea-level rise.  相似文献   

Die Verölung der Oberflächengewässer durch die Kleinschiffahrt     

H. E. Von Vogel 《Aquatic Sciences - Research Across Boundaries》1963,25(1):119-151

Ohne Zusammenfassung  相似文献   

Generation of flow nets using fem nodal potentials and bilinear shape functions     

Yuehui Fan  F. D. Tompkins  E. C. Drumm  R. D. Von Bernuth 《国际地质力学数值与分析法杂志》1992,16(6):425-437

A method for generating both equipotential lines and streamlines directly based upon nodal potentials and bilinear shape functions is presented. The method involves post-processing a finite element (FE) solution utilizing typical four-node isoparametric quadrilateral elements. The application of the method can be important in the interpretation of FE analysis results, especially when inhomogeneous, anisotropic, unconfined or/and other complicated conditions exist. Compared with conventional techniques to generate flow nets which depend upon both the potential and stream functions, the method presented is simpler and more powerful.  相似文献   

An analysis of carrier phase differential kinematic GPS positioning using DynaPos     

Karen?M.?CoveEmail author  Marcelo?C.?Santos 《GPS Solutions》2004,8(4):210-216

A series of activities have been carried out at the University of New Brunswick in an effort to evaluate advances in long-range marine kinematic differential positioning. These activities involved processing and analysis of GPS carrier phase kinematic data sets. Some of the data was collected by UNB and some was provided by The XYZs of GPS Inc. Data were collected using Trimble 5700 and Ashtech Z-12 receivers. The data sets were processed using the software DynaPos provided by the The XYZs of GPS Inc. The best results obtained in our analysis indicate an agreement of 5 cm RMS for the horizontal component and 12 cm RMS for the vertical component between two ionospheric-delay free solutions, in baselines varying from 40 to 100 km.  相似文献