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31.
Turbulent flux observations and modelling over a shallow lake and a wet grassland in the Nam Co basin,Tibetan Plateau 总被引:2,自引:1,他引:1
Tobias?BiermannEmail author Wolfgang?Babel Weiqiang?Ma Xuelong?Chen Elisabeth?Thiem Yaoming?Ma Thomas?Foken 《Theoretical and Applied Climatology》2014,116(1-2):301-316
The Tibetan Plateau plays an important role in the global water cycle and is strongly influenced by climate change. While energy and matter fluxes have been more intensely studied over land surfaces, a large proportion of lakes have either been neglected or parameterised with simple bulk approaches. Therefore, turbulent fluxes were measured over wet grassland and a shallow lake with a single eddy-covariance complex at the shoreline in the Nam Co basin in summer 2009. Footprint analysis was used to split observations according to the underlying surface, and two sophisticated surface models were utilised to derive gap-free time series. Results were then compared with observations and simulations from a nearby eddy-covariance station over dry grassland, yielding pronounced differences. Observations and footprint integrated simulations compared well, even for situations with flux contributions including grassland and lake. The accessibility problem for EC measurements on lakes can be overcome by combining standard meteorological measurements at the shoreline with model simulations, only requiring representative estimates of lake surface temperature. 相似文献
32.
Data from the 13 May 1971 β Scorpii occultation by the southern polar region of Jupiter (Vapillon et al., 1973, Astron. Astrophys. 29, 135-149) are re-analyzed with current methods. We correct the previous results for an inacurrate background estimation and calculate new temperature profiles, that are now consistent with the results of other observers of this occultation, as well as with the current knowledge of the jovian atmosphere. The characteristics of the profiles of temperature gradient and the spectral behavior of the temperature fluctuations are found to be similar to the results of previous investigations of planetary atmospheres and in agreement with the presence of atmospheric propagating gravity waves in the jovian atmosphere. We use a wavelet analysis of the temperature profiles to identify the dominant modes of wave activity and compare the reconstructed temperature fluctuations to model-generated gravity waves. 相似文献
33.
Limnological effects of growth and cessation of agricultural land use in Ladoga Karelia: sedimentary pollen and diatom analyses 总被引:2,自引:0,他引:2
Juha O.?MiettinenEmail author Heikki?Simola Elisabeth?Gr?nlund Jaana?Lahtinen Riitta?Niinioja 《Journal of Paleolimnology》2005,34(2):229-243
Reference conditions and changes in limnological conditions during the 20th century have been inferred in a palaeolimnological study of sediments from six lakes of the District of Sortavala, Karelian Republic, Russia. The area is former Finnish territory, which was in intensive use for arable field cultivation until the World War II, when the area was ceded to the Soviet Union. After the war, farming was resumed by cattle sovkhozes, and the fields were mainly used as pasture without regular ploughing. We have studied the history of eutrophication and recovery in some lakes related with the changes of agricultural intensity. The trophic level of the lakes was studied by sedimentary diatom assemblages, including reconstructions of total phosphorus levels in the lakes based on a weighted averaging transfer function. Pollen analyses were used to assess the changes in the land use near the lakes. Valuable background data on all the lakes used in the present study are provided by a doctoral thesis done on their limnology from the 1920s. According to our results, the four lakes situated on the clayey lowlands near the coast of Lake Ladoga were eutrophicating during the first half of the 20th century, and in two of them, a rapid recovery is evident. In two lakes situated in hilly landscape with limited agricultural activities, only minor changes are recorded in the diatom profiles. 相似文献
34.
Andreas Matzarakis Martin H?mmerle Elisabeth Koch Ernest Rudel 《Theoretical and Applied Climatology》2012,110(4):645-658
The climate tourism potential of a region can be described by methods used in human biometeorology and applied climatology. Frequency analyses based on complex thermal bioclimatic indices (e.g. physiologically equivalent temperature) and diagrams of precipitation patterns based on thresholds offer new approaches of visualisation. An integral approach for tourism climatologic analyses is provided by the climate?Ctourism/transfer?Cinformation?Cscheme that also bases on frequency distributions of relevant factors and parameters which are important for a destination. The knowledge about the vertical variability of tourism climatologic factors is of high importance because of the several kinds of tourism activities affected by weather. The same holds for a quantification of extreme events like heat waves because of their possible effects on health and recreation over a year's course. The results show that the vertical gradient of bioclimatic and tourism-related parameters can be of value when developing strategies of adaption to climate change. 相似文献
35.
The interrelated use of geological information and other types of geoinformation in local governments 下载免费PDF全文
Elisabeth Häggquist 《Transactions in GIS》2017,21(5):1010-1022
There is a growing interest in the use of geoinformation in government decision‐making. Studies on the usability of geological information, which is one type of geoinformation, have however been scarce in the literature. A system built for an efficient organization may, therefore, not be catering to the needs of the individual user and understanding the perceived barriers to using geological information should be an important goal of geodata implementation. The objectives of this article are to: (1) investigate whether the analyses of user patterns are improved by considering an interrelated estimation with two types of geoinformation, and (2) explore whether there are gender differences in how peer advice affects the use of geoinformation. The data were collected in 2014 through a web survey, and the sample consisted of 390 women and 287 men working in Swedish municipalities. The results indicates a more accurate prediction pattern when a secondary geoinformation decision was included, thus suggesting that different types of geoinformation should be jointly analyzed. The officials tend to use both types of geoinformation, alluding to a demand for combined geoinformation products among the target population. Finally, there is evidence of women's decision to use geoinformation being affected by peer advice. 相似文献
36.
Elisabeth Rathschüler 《Theoretical and Applied Climatology》1948,1(1):17-31
Zusammenfassung Auf Grund von Registrierungen an eng benachbarten Stationen, die im obersten Salzachtal im Land Salzburg in verschiedenen Höhenlagen zwischen Tal (900 m) und Kammhöhe (2000 m) des begleitenden Gebirgszuges gelegen waren, werden Tagesgänge der relativen Feuchtigkeit, des Dampfdrucks und der spezifischen Feuchtigkeit für Schönwettertage abgeleitet (Tab. 2). Im Vergleich dieser Stationen zeigt sich der Übergang der Form der Tagesgänge der relativen Feuchtigkeit (Abb. 2 und 3) und des Dampfdrucks (Abb. 4) von dem Typ der Niederung zu dem der Bergstationen. Der Einfluß der Konvektion und der über die feuchten Hänge streichenden Hangaufwinde auf diese Umgestaltung der Tagesgänge wird für die einzelnen Jahreszeiten quantitativ nachgewiesen und diskutiert.
Mit 4 Textabbildungen. 相似文献
Summary Using records taken at closely neighbouring stations situated in the uppermost valley of the Salzach in the province of Salzburg at different levels between the valley-bottom (900 m) and the height of the adjacent mountain-ridge (2000 m) the diurnal variation of relative humidity, vapor pressure and specific humidity are derived for fair weather days (Tab. 2). The comparison of these stations shows the transition of the diurnal variation of relative humidity (Fig. 2 and 3) and vapor pressure (Fig. 4) from the ground type to that of the mountain stations. The influence of the convection and of the ascending currents passing over the moist slopes upon this modification of the diurnal variation is quantitatively proved and discussed for the different seasons.
Résumé Sur la base d'enregistrements à des stations étroitement voisines situées dans la vallée la plus haute de la Salzach en province de Salzbourg à des niveaux differents entre la vallée (900 m) et l'altitude de la crête de la chaine adjacente de montagnes (2000 m) les variations diurnes de l'humidité relative, de la pression de vapeur et de l'humidité spécifique sont derivées pour les jours de beau temps (Tab. 2). En comparaison de cettes stations la transition de la forme des variations diurnes de l'humidité relative (Fig. 2 et 3) et de la pression de vapeur (Fig. 4) se présente du type de vallée à celui des stations de montagne. L'influence de la convection et des courants ascendants passant sur les pentes humides sur la transformation des variations diurnes est démontrée quantitativement et discutée.
Mit 4 Textabbildungen. 相似文献
37.
State governments in the United States are well placed to identify opportunities for mitigation and the needs for adaptation to climate change. However, the cost of these efforts can have important implications for budgets that already face pressures from diverse areas such as unfunded pensions and growing health care costs. In this work, the current level of spending on climate-related activities at the state level are evaluated and policy recommendations are developed to improve financial management practices as they relate to climate risk. An examination of state budgets reveals that climate mitigation and adaptation activities represent less than 1% of spending in most states. The data collection highlights the obstacles to collecting accurate spending data and the lack of budgetary and accounting procedures in place. More importantly, the difficulty in benchmarking these activities poses challenges for the analysis of state-level policies as well as planning and modelling future climate-related spending. Other policy contexts, including public pensions and infrastructure, can provide guidance on budgetary and accounting tools that may help states prepare for and more efficiently manage climate-related expenditures.
Key policy insights
Climate change mitigation and adaptation will require substantial investments across many levels of government on a wide range of activities.
Currently, US states are not clearly demarcating climate expenditures, hindering the identification of climate-related budgetary risks.
In the absence of guidelines, these longer term fiscal outlays may remain chronically underfunded in favour of more near-term spending priorities.
Establishing appropriate financial management and data collection practices is important for more sophisticated cost-effectiveness and policy analyses.
38.
Light element nucleosynthesis is an important chapter of nuclear astrophysics. Specifically, the rare and fragile light nuclei
Lithium, Beryllium and Boron (LiBeB) are not generated in the normal course of stellar nucleosynthesis (except 7Li) and are, in fact, destroyed in stellar interiors. This characteristic is reflected in the low abundance of these simple
species. Up to recently, the most plausible interpretation was that Galactic Cosmic Rays (GCR) interact with interstellar
CNO to form LiBeB. Other origins have been also identified: primordial and stellar (7Li) and supernova neutrino spallation (7Li and 11B). In contrast, 9Be, 10B and 6Li are pure spallative products. This last isotope presents a special interest since the 6Li/7Li ratio has been measured recently in a few halo stars offering a new constraint on the early galactic evolution of light
elements. Optical measurements of the beryllium and boron abundances in halo stars have been achieved by the 10 meter KECK
telescope and the Hubble Space Telescope. These observations indicate a quasi linear correlation between Be and B vs Fe, at
least at low metallicity, which, at first sight, is contradictory to a dominating GCR origin of the light elements which predicts
a quadratic relationship. As a consequence, the theory of the origin and evolution of LiBeB nuclei has to be refined. Aside
GCRs, which are accelerated in the general interstellar medium (ISM) and create LiBeB through the break up of CNO by fast
protons and alphas, Wolf-Rayet stars (WR) and core collapse supernovae (SNII) grouped in superbubbles could produce copious
amounts of light elements via the fragmentation in flight of rapid carbon and oxygen nuclei colliding with H and He in the
ISM. In this case, LiBeB would be produced independently of the interstellar medium chemical composition and thus a primary
origin is expected. These different processes are discussed in the framework of a galactic evolutionary model. More spectroscopic
observations (specifically of O, Fe, Li, Be, B) in halo stars are required for a better understanding of the relative contribution
of the various mechanisms. Future tests on the injection and acceleration of nuclei by supernovae and Wolf Rayet relying on
gamma-ray line astronomy will be invoked in the perspective of the European INTEGRAL satellite.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
39.
Accumulation in Svalbard glaciers deduced from ice cores with nuclear tests and Chernobyl reference layers 总被引:1,自引:0,他引:1
Jean Francis Pinglot Michel Pourchet Bernard Lefauconnier Jon Ove Hagen Elisabeth Isaksson Rein Vaikmäe Kokichi Kamiyama 《Polar research》1999,18(2):315-321
Mean net annual balance and the related spatio-temporal variations have been determined on the basis of well-dated artificial layers in shallow ice cores (Chernobyl, 1986, and atmospheric thermonuclear tests, mainly in 1961-62 in Novaya Zemlya). Seventy ice cores from 13 Svalbard glaciers have been analysed. On each glacier, in its accumulation area and at the highest elevation, one ice core was recovered down to about 40 m and sampled for radioactivity measurements to determine the 1986 and 1962-63 layer (1954 was the initial date of the nuclear tests). For each glacier, at least five complementary ice cores from the accumulation area were analysed to determine the Chernobyl reference layer. Six ice cores exhibit both the Chernobyl and nuclear tests layers and are of special interest in this study.
This work provides new data on the deposition rates of natural and artificial radioisotopes. Using ice cores samples from the Arctic glaciers, even with superimposed ice accumulation, it is possible to distinguish between the Chernobyl and the nuclear tests fallouts. This work also shows that the mean annual net balance did not significantly change for at least five ice core locations in the Svalbard glaciers for the two periods extending from 1963 to 1986 to the recent date of drilling. 相似文献
This work provides new data on the deposition rates of natural and artificial radioisotopes. Using ice cores samples from the Arctic glaciers, even with superimposed ice accumulation, it is possible to distinguish between the Chernobyl and the nuclear tests fallouts. This work also shows that the mean annual net balance did not significantly change for at least five ice core locations in the Svalbard glaciers for the two periods extending from 1963 to 1986 to the recent date of drilling. 相似文献
40.
Johannes Becherer Jacobus Hofstede Ulf Gräwe Kaveh Purkiani Elisabeth Schulz Hans Burchard 《Ocean Dynamics》2018,68(1):131-151
The impact of sea level rise (SLR) on the future morphological development of the Wadden Sea (North Sea) is investigated by means of extensive process-resolving numerical simulations. A new sediment and morphodynamic module was implemented in the well-established 3D circulation model GETM. A number of different validations are presented, ranging from an idealized 1D channel over a semi-idealized 2D Wadden Sea basin to a fully coupled realistic 40-year hindcast without morphological amplification of the Sylt-Rømøbight, a semi-enclosed subsystem of the Wadden Sea. Based on the results of the hindcast, four distinct future scenarios covering the period 2010–2100 are simulated. While these scenarios differ in the strength of SLR and wind forcing, they also account for an expected increase of tidal range over the coming century. The results of the future projections indicate a transition from a tidal-flat-dominated system toward a lagoon-like system, in which large fractions of the Sylt-Rømøbight will remain permanently covered by water. This has potentially dramatic implications for the unique ecosystem of the Wadden Sea. Although the simulations also predict an increased accumulation of sediment in the back-barrier basin, this accumulation is far too weak to compensate for the rise in mean sea level. 相似文献