1. Ivančić, I., D. Herak, S. Markušić, I. Sović and M. Herak (2006): Seismicity of Croatia in the period 2002-2005. Geofizika, 23, 87-103.
ABSTRACT:
During the 2002–2005 period a total of 3459 earthquakes were located in Croatia and its neighbouring areas with 15 main events registering magnitudes from 4.0 to 5.5. Seismically the most prominent were the two strongest earthquake sequences recorded in the central part of the Adriatic Sea, near Jabuka Island (the first one with the mainshock on March 29, 2003, 17:42, ML = 5.5, and the second, weaker, with the mainshock on November 25, 2004, 6:21, ML = 5.2). In the epicentral area W and NW of the Jabuka Island 781 earthquakes were confidently located (28 events with magnitudes equal to or larger than 4.0). Seismically active coastal part of Croatia, especially its southern part exhibited the seismicity within well-known epicentral areas. The earthquake with the magnitude ML = 5.5, recorded in the Imotski–Grude area, on May 23, 2004 at 15:19 (Imax = VI–VII °MSK) was the second strongest event during the studied period. Continental part of Croatia experienced moderate seismicity during the observed period, with earthquakes of magnitudes ML ≤ 3.9.
Keywords: Seismicity, Croatia
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2. Verbanac, and M. Korte (2006): The geomagnetic field in Croatia. Geofizika, 23, 105-117.
ABSTRACT:
In this study we present the distribution of the geomagnetic field components: declination (D), horizontal intensity (H), inclination (I), total field intensity (F), as well as the crustal and anomaly geomagnetic fields over the region of Croatia for the 2003.76 epoch, calculated using the Comprehensive model CM4 (Sabaka et al., 2004).
The smooth change of D, H, I and F values over the whole territory is found. The map of the crustal field reveals symmetric north-south and east-west isolines behaviour, with the minimum value in the middle part of the north Croatia. The highest values are found at the Adriatic see, along all the coast and at the very eastern part of the country. The anomalies are everywhere negative, with the smallest values in the north-east of Croatia.
The predicted annual secular variation for the Croatian region is: 0.06 °/year for D, 11 nT/year for H, 0.02 °/year for I and 50 nT/year for F.
In order to get an insight in the structure of the local field and determine the best location for the observatory, we made use of a set of intensity data measured over the northern part of middle Croatia in 2003. The obtained detailed anomaly map reveals weak small-scale negative structure (–40 nT in average).
Predicted crustal and anomaly fields suggest that the best place for the observatory would be in the middle northern part of Croatia, what is further constrained with the anomalies obtained on the surveyed area.
With the present study we aim to pave a way for more detail research in the field of geomagnetism in Croatia, which has commenced again after more than 50 years’ gap.
Keywords: geomagnetic field, geomagnetic measurements, geomagnetic models, geomagnetic observatory
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3. Nami, H.G. (2006): Preliminary paleomagnetic results of a terminal pleistocene/holocene record from northeastern Buenos Aires province (Argentina). Geofizika, 23, 119-141.
ABSTRACT:
Paleomagnetic data from the Lomas del Mirador (34° 39.29’ S, 58° 32.17’ W) sedimentary section in northeastern Buenos Aires province (Argentina) comprises 149 oriented samples that record a significant but gentle gradual change in the geomagnetic field at the terminal Pleistocene and Holocene. Based on rock magnetic and detrital remanence experiments, the deposit seems to be a good recorder of the past geomagnetic field behavior. The characteristic remanent magnetization (ChRM), determined by progressive AF demagnetization, shows that the sections registered normal and intermediate polarities during the terminal Pleistocene/Holocene. The PSV is characterized by a large variation with ~ 80° difference in inclination in both sections and a significant but gentle westward shift in the declination in the upper part. A similar trend was observed in the paleomagnetic record registered in other sections from northeastern Argentina. This remarkably large PSV, especially the inclination record, became a reliable chronostratigraphical marker for latest Pleistocene/Holocene sedimentary deposits in northeastern Buenos Aires. VGPs resemble those registered during terminal Pleistocene and Holocene in the southern cone of South America. Palaeomagnetic poles for the sections other contemporaneous sites from northeastern Argentina fall some ~ 5–15° away from the Earth’s rotation’s axis
Keywords: Paleomagnetism, paleosecular variation, terminal Pleistocene, Holocene, South America, Argentina
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4. Ninić, N., Z. Jurić and S. Nižetić (2006): Thermodynamical aspect of definitions ˝CAPE˝ and ˝TCAPE˝. Geofizika, 23, 143-154.
ABSTRACT:
The paper analyses the thermodynamical aspect of the terms CAPE and TCAPE, defined in the standard way according to Brunt (1941) and in another way in Renno and Ingersol’s paper (1996). Based on this, in this paper it is pointed out that the thermodynamical foundations for the difference existing between the two definitions. The analyses itself is based on the presentation of all the relevant terms in thermodynamics diagrams and relations for internal-equilibrium processes and processes with internal friction.
The paper shows the internal friction which Renno and Ingersol take into consideration and make their definition of CAPE and TCAPE different from the standard one and not equivalent to it. In this connection, only according to the standard definition CAPE and TCAPE represent the maximum work which is real in advance calculable measure of convective circulation intensity.
Keywords: maximum work, CAPE, TCAPE, energy dissipation
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5. Fuchs, Ž. and A. Marki (2006): Large-Scale Modes of the Tropical Atmosphere. Part I: Analytical Modeling of Convectively Coupled Kelvin Waves Using the Boundary-Layer Quasiequilibrium Approximation. Geofizika, 23, 155-164.
ABSTRACT:
One way of modeling the convectively coupled Kelvin waves in an equatorial non-rotating atmosphere is presented. It implements a simple linear, analytical model using the boundary-layer quasiequilibrium approximation and wind-induced surface heat exchange. The dynamics of the model are based on the assumption that the vertical heating profile has the shape of the first baroclinic mode. The vertical velocity has two sinusoidal components of different vertical wavelengths. One component corresponds to deep convection and the imposed heating profile while the other component, with shallower vertical wavelength, defines the phase speed of the convectively coupled Kelvin wave.
The results of the model show fast Kelvin waves that resemble adiabatic modes with the vertical wavelength being twice the depth of the troposphere and convectively coupled Kelvin waves that are damped and propagate with phase speed of 18 m/s. Wind-induced surface heat exchange causes the instability of the convectively coupled Kelvin waves, but only for very long wavelengths.
The value of the model is that under the single dynamical assumption of the vertical heating profile and using the boundary-layer quasiequilibrium assumption it yields the observed phase speed for the convectively couple Kelvin waves.
Keywords: Kelvin waves, convection
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6. Cvitaš,
T., N. Kezele, L. Klasnic and G. Šorgo
(2006): Ozone Measurement on Mount Srđ near Dubrovnik, Croatia. Geofizika,
23, 165-171.
ABSTRACT:
Results and analysis of ozone monitoring at station Sr| (46.25° N, 17.45° E, 412 m a.s.l.) near Dubrovnik from 1998 – 2005 are reported. It is confirmed that this is an unpolluted place despite of high summer solar radiation which could contribute to the photochemical air pollution formation. There is no significant trend in ozone levels found during this time and the overall average ozone fraction is found to be 46 ppb for the summer periods
Keywords:
ozone measurements, photochemical air pollution, Dubrovnik
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7. Volarić,
B., D. Skoko and I. Penzar
(2006): Geofizičar Andro Gilić – život i djelo. Geofizika, 23, 173-188.
ABSTRACT:
Dr. sc. Andro Gilic (Rijeka 30. 11. 1889. – Volosko 15. 9. 1977.) bio je prvi visokoskolovani geofizicar u Hrvatskoj. Studirao je u Becu, Göttingenu i Berlinu. Na Geofizickom zavodu u Zagrebu radio je od 1918. do 1923. i od 1948. do 1952. Izmedju tih godina zaposlen je u upravi Lloyda. U Zagrebu na Gospodarsko-sumarskom fakultetu predavao je meteorologiju s klimatologijom, a na novoosnovanom Tehnickom fakultetu 1920. uvodi predavanja iz vise geodezije. Fiziku i oceanografiju predavao je na zagrebackom Prirodoslovno-matematickom fakultetu. Koncem 1920. zapocinje objavljivati prve sluzbene vremenske prognoze za javnost u Hrvatskoj, sluzeci se sinoptickim metodama na najvisoj znanstvenoj razini onoga doba. Pronasao je i objavio (1948.) zapise o hladnim zimama na Krku pocetkom 17. stoljeca. Kao veliki prakticar nastojao je doci do dovoljno tocnih rezultata na sto jednostavniji nacin, sto je bilo vazno u doba prije elektronickih racunala. U tu svrhu razradio je vise originalnih grafickih postupaka, a u strucnim clancima izvjestavao je o novo izdanim tablicnim pomagalima takve vrste. Razradio je postupak plasticnijeg prikazivanja reljefa tla na zemljopisnim kartama (1930.). Za lakse odredjivanje koordinata Sunca, Mjeseca i planeta konstruirao je sferno-astronomski trokut za zemljopisnu sirinu Zagreba (1947a). Iznacao je originalni, graficki nacin lociranja epicentra dalekih potresa (1957., 1959.). Od 1943. do 1952. pratio je Suncevu aktivnost odredjujuci svakodnevno broj i polozaj pjega i grupa na Suncu (1946., 1947b, 1950., 1952.). Njegova sustavna fotografska opazanja Sunceve ploce za vrijeme totalne pomrcine u veljaci 1961. ostala su zabiljezena veoma uspjelim nizom snimaka (1967.).
Keywords:
Gilic Andro, Geofizicki zavod u Zagrebu, Sunceve pjege, lociranje epicentara
dalekih potresa, kartografski prikaz reljefa, prognoza vremena
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