Frequency Changes of Weather Types in the Alpine Region since 1945     

G. Stefanicki  P. Talkner  R. O. Weber 《Theoretical and Applied Climatology》1998,60(1-4):47-61

Summary The annual occurrence of different weather types of Schüepp’s synoptic classification in the Alpine region has significantly changed since the beginning of its recording in 1945. The annual frequency (number of days per year) has shifted towards more convective and less advective weather types. Since 1945 the number of long-lasting convective episodes rose and the number of long-lasting advective episodes lessened. Most of these changes took place in winter. The annual frequencies of weather types and the annual mean of certain local meteorological parameters are significantly correlated. On the large scale there is a strong interdependence between the high pressure weather type and the North Atlantic Oscillation (NAO) index which is based on the sea-level pressure difference between Portugal and Iceland. Received July 28, 1997 Revised November 18, 1997  相似文献   

On the upper bounding approach to thermal convection at moderate Rayleigh numbers, II. Rigid boundaries     

Joe M. Straus 《Dynamics of Atmospheres and Oceans》1976,1(1):77-90

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Geochronology: Radiometric dating of rocks and minerals: Christopher T. Harper (Editor), 1973. Benchmark Papers in Geology. Dowden, Hutchinson and Ross, Stroudsburg, Pa., xv + 469 pp., £ 12.00     

Jon N. Weber 《Earth》1974,10(4):349

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Extension of a polar ionospheric current to the nightside equator     

Tohru Araki  Joe H. Allen  Yuriko Araki 《Planetary and Space Science》1985,33(1):11-16

A detailed analysis of rapid-run magnetograms from Guam (geomagnetic latitude = 4.2°) revealed that there are two kinds of geomagnetic sudden commencement (SC) observed in nighttime. One is the ordinary SC consisting of a main impulse only which has a smooth rise of the H-component. The other is a superposition by a small positive impulse on the very beginning part of the smooth rise of the main impulse and consequently the SC starts with a small stepwise increase of the H-component. The latter type of SC occurs between 20 and 08 h L.T. and its occurrence rate takes the maximum value of about 50% around 03 h L.T. Corresponding magnetograms from a dayside equatorial station (Huancayo, geomagnetic latitude = ?0.7°) were examined and a good correlation was found between the stepwise SC at the nightside (Guam) and SC¹ with a preliminary reverse impulse (PRI) at the dayside (Huancayo). Since PRI observed at the dayside equator may be interpreted as an extension of an ionospheric current due to an dusk-to-dawn electric field impressed on the polar ionosphere, our results show that a polar originating ionospheric current can extend to the nightside equator and produce a small but observable magnetic effect in spite of much reduced nighttime ionospheric conductivity.  相似文献   

Cosmochemical and spectroscopic properties of Northwest Africa 7325—A consortium study          下载免费PDF全文

I. Weber  A. Morlok  A. Bischoff  H. Hiesinger  D. Ward  K. H. Joy  S. A. Crowther  N. D. Jastrzebski  J. D. Gilmour  P. L. Clay  R. A. Wogelius  R. C. Greenwood  I. A. Franchi  C. Münker 《Meteoritics & planetary science》2016,51(1):3-30

This work is part of a project to build an infrared database in order to link IR data of planetary materials (and therefore possible Mercury material) with remote sensing observations of Mercury, which will probably be obtained by the MERTIS instrument on the forthcoming BepiColombo mission. The unique achondrite Northwest Africa (NWA) 7325, which has previously been suggested to represent the first sample from Mercury, was investigated by optical and electron microscopy, and infrared and Raman spectroscopy. In addition, the oxygen, strontium, xenon, and argon isotopes were measured and the abundance of selected trace elements determined. The meteorite is a cumulate rock with subchondritic abundances of HFSE and REE and elevated Sr contents, which underwent a second heating and partial remelting process. Oxygen isotope measurements show that NWA 7325 plots in the ureilite field, close to the ALM‐A trachyandesitic fragment found in the unique Almahata Sitta meteorite breccia. On the other hand, mineralogical investigations of the pyroxenes in NWA 7325 provide evidence for similarities to the lodranites and acapulcoites. Furthermore, the rock is weakly shocked and argon isotope data record ancient (~4.5 Ga) plateau ages that have not been reset. The sample records a cosmogenic exposure age of ~19 Ma. Systematics of Rb‐Sr indicate an extreme early volatile depletion of the precursor material, similar to many other achondrite groups. However, despite its compositional similarities to other meteorite groups, our results suggest that this meteorite is unique and unrelated to any other known achondrite group. An origin for NWA 7325 as a sample from the planet Mercury is not supported by the results of our investigation. In particular, the evidence from infrared spectroscopy indicates that a direct relationship between NWA 7325 and the planet Mercury can be ruled out: no acceptable spectral match between laboratory analyses and remote sensing observations from Mercury has been obtained. However, we demonstrate that infrared spectroscopy is a rapid and nondestructive method to characterize mineral phases and thus an excellent tool for planetary surface characterization in space missions.  相似文献   

Border Tax adjustment – legal perspective     

Rolf H. Weber 《Climatic change》2015,133(3):407-417

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Solar Spectral Irradiance Variations in 240 – 1600 nm During the Recent Solar Cycles 21 – 23     

J.?PagaranEmail author  M.?Weber  M.?T.?DeLand  L.?E.?Floyd  J.?P.?Burrows 《Solar physics》2011,272(1):159-188

Regular solar spectral irradiance (SSI) observations from space that simultaneously cover the UV, visible (vis), and the near-IR (NIR) spectral region began with SCIAMACHY aboard ENVISAT in August 2002. Up to now, these direct observations cover less than a decade. In order for these SSI measurements to be useful in assessing the role of the Sun in climate change, records covering more than an eleven-year solar cycle are required. By using our recently developed empirical SCIA proxy model, we reconstruct daily SSI values over several decades by using solar proxies scaled to short-term SCIAMACHY solar irradiance observations to describe decadal irradiance changes. These calculations are compared to existing solar data: the UV data from SUSIM/UARS, from the DeLand & Cebula satellite composite, and the SIP model (S2K+VUV2002); and UV-vis-IR data from the NRLSSI and SATIRE models, and SIM/SORCE measurements. The mean SSI of the latter models show good agreement (less than 5%) in the vis regions over three decades while larger disagreements (10 – 20%) are found in the UV and IR regions. Between minima and maxima of Solar Cycles 21, 22, and 23, the inferred SSI variability from the SCIA proxy is intermediate between SATIRE and NRLSSI in the UV. While the DeLand & Cebula composite provide the highest variability between solar minimum and maximum, the SIP/Solar2000 and NRLSSI models show minimum variability, which may be due to the use of a single proxy in the modeling of the irradiances. In the vis-IR spectral region, the SCIA proxy model reports lower values in the changes from solar maximum to minimum, which may be attributed to overestimations of the sunspot proxy used in modeling the SCIAMACHY irradiances. The fairly short timeseries of SIM/SORCE shows a steeper decreasing (increasing) trend in the UV (vis) than the other data during the descending phase of Solar Cycle 23. Though considered to be only provisional, the opposite trend seen in the visible SIM data challenges the validity of proxy-based linear extrapolation commonly used in reconstructing past irradiances.  相似文献   

The Value of Practice-Based Knowledge     

Edward P. Weber  Jill M. Belsky  Denise Lach  Antony S. Cheng 《社会与自然资源》2014,27(10):1074-1088

Increasing recognition of the value of practice-based or experiential knowledge in natural resource management justifies the creation of a new category of articles in Society & Natural Resources that we are calling Practice-Based Knowledge (PBK). The rationale for focusing on PBK is due to its key role in the emergence of hybrid governance institutions across state, market, and civil society, understanding the complexity of dynamic socioecological systems, recognizing the challenges of multiple knowledge systems and context-specific practices, embracing the power of informal institutions and civic science, and engaging debates on the growing prevalence of market-oriented conservation. The goal is to provide a dedicated space within the published, peer-reviewed literature for scholars, government officials, nonprofit managers, and engaged citizens to share experiences informed by practical action. Relevant and timely practice-based insights may improve understanding and management of social and ecological processes and systems, while also offering the potential to contribute to theory.  相似文献   

In Situ Maintenance of Traditional Ecological Knowledge on Malekula Island,Vanuatu     

Joe McCarter  Michael C. Gavin 《社会与自然资源》2014,27(11):1115-1129

Traditional ecological knowledge (TEK) guides resource management across the globe, but is at risk amid social and ecological change. This has prompted numerous calls for TEK maintenance efforts, but these remain largely unexamined in the literature. Here, we discuss three examples of in situ TEK maintenance from Malekula Island in Vanuatu, locally known as kastom schools. Based on qualitative data, we find that the kastom schools may create several opportunities to maintain TEK (e.g., establishing local control over education), and argue that they represent the creative and adaptive management of tradition in dynamic social–ecological contexts. However, a number of challenges, both practical (e.g., lack of funding) and epistemological (e.g., changing modes of cultural transmission), threaten the efficacy of the kastom schools. We argue that in situ modes of TEK maintenance have promise, but that issues of power and heterogeneity require serious consideration if such measures are to succeed.  相似文献   

Data-driven Expansion of Dense Regions – A Cartographic Approach in Literary Geography     

Anne-Kathrin Weber Reuschel 《The Cartographic journal》2014,51(2):123-140

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