Record of the Sedimentary Dynamics and Climatic Variability Within the Sedimentary Filling of Mchiguig Wetland During the Late Holocene

This work aimed to study the cyclicity of the geochemical chemical parameters and the carbonate percentages along a 59 cm core from the sebkha of Mchiguig, Central Tunisia. In fact, from the bottom upwards, six climatic phases were recorded including the Warming Present (Great Acceleration), the Late Little Ice Age (Anthropocene), the Early Little Ice Age, the Medieval Climatic Anomaly, the Dark Age, and the Roman Warm Period. In fact, the spectral analysis of the studied parameters visualized many cycles. Those cycles are related to sun activity, oceanographic, and atmospheric factors. Solar activity generated 500 yr cycles; however, the oceanographic circulation generated other cycles of 1500 yr and 700-800 yr. The 1500 yr cycle may be the result of the solar activity and NAO-like circulation.

ANALISIS VARIASI FREKUENSI KRITIS DAN KETINGGIAN LAPISAN IONOSFER DI ATAS KUPANG

ABSTRAK Variasi perubahan frekuensi kritis lapisan F2 (foF2) dan ketinggian lapisan F2 (h'F2) di atas Kupang selama tahun 2014 mengalami perubahan yang bervariasi dimana hal ini bergantung pada aktivitas matahari, semakin tinggi tingkat aktivitas matahari semakin tinggi pula tingkat variasi pada foF2 dan h'F2, sebaliknya semakin rendah tingkat aktivitas matahari semakin berkurang pula tingkat variasi foF2 dan h'F2 variasi perubahan terhadap lapisan F diindikasikan dengan penurunan dan peningkatan nilai foF2 dan h'F2. Peningkatan nilai foF2 rata-rata terjadi pada pukul 07.00 WITA mencapai maksimumnya pada pukul 12.00-14.00 WITA siang hari dan dikuti dengan penurunan nilai foF2 pada malam hari yang mencapai minimumnya pada pukul 05.00-06.00 WITA pagi. Selama tahun 2014, ketinggian lapisan F2 memiliki tiga pola peningkatan yang berbeda, (1) peningkatan ketinggian pada jam tengah hari seperti yang terjadi pada bulan Januari – April, (2) peningkatan pada jam tengah malam hingga menjelang matahari terbit, jam-jam tengah hari dan sore hingga malam hari terjadi pada bulan Mei – Agustus (3) peningkatan pada pada jam tengah malam hingga menjelang matahari terbit dan jam-jam tengah hari seperti pada bulan September – Desember. Dalam pemanfaatannya sebagai media pantul gelombang komunikasi radio frekuensi tinggi (HF), karakteristik ionosfer di atas Kupang selama tahun 2014, memiliki kemampuan memantulkan gelombang frekuensi tinggi berada pada rentang 2-19.2 MHz dengan ketinggian yang berada pada rentang 179 – 550 Km. Akan mengakibatkan gagalnya komunikasi radio frekuensi tinggi, apabila menggunakan frekuensi lebih besar atau lebih kecil dari frekuensi yang dapat bekerja tersebut. Kata Kunci : Aktivitas matahari, Frekuensi kritis F2, ketinggian lapisan F2, komunikasi radio, frekuensi tinggi. ABSTRACT The ionospheric critical frequency (foF2) and the F2 layer height (h'F2) variation over Kupang during 2014 period unchanged varied where it is dependent on solar activity, the higher the level of solar activity the higher the level of variation in foF2 and h'F2, conversely the lower level of sun activity diminishing the level of variation foF2 and h'F2 variation changes to the F layer is indicated by a decrease and an increase in the value of foF2 and h'F2. Increasing the value of the average foF2 occurred at 07:00 pm reaching it's maximum at noon and 12:00 to 14:00 pm followed by impairment foF2 at night, which reached it's minimum at morning 5:00 to 6:00 pm. During 2014, the altitude of the F2 has three patterns different upgrade, (1) an increase in height on the hour midday as happened in January-April, (2) an increase in the hours of midnight until before sunrise, hours noon and afternoon until the evening occurred in May-August (3) an increase in the hours of midnight until near sunrise and midday hours as in September-December. In the media utilization as reflected waves of high frequency radio communications (HF), characteristics of the ionosphere above Kupang during 2014, has the ability to reflect high frequency waves that are in the range of 2 - 19.2 MHz with a height that is in the range 179-550 Km. Will lead to high frequency radio communication failure, when using a frequency of greater or smaller than the frequency that can work. Keywords: solar activity, the critical frequency of F2, F2 layer heights, radio communications, high frequency.

Moon/sun – suicide

Introduction: Findings concerning the effects of moon phases and sun activity on suicide are mixed in the international literature. Aim: Our aim was to examine the hypothesised effects according to gender and age on Hungarian data covering more than 30 years. Methods: Time series ARIMA models and dynamic regression models were applied in our analysis. Results: Among women aged 20–49 years, a significant increase in the risk of suicide has been observed during proton solar events. At the same time, among women aged 50–59 years a slight but significant decrease has been identified in the risk of suicide during magnetic storms and full moons. Conclusion: Proton solar events, geomagnetic storms and moon phases caused changes in the risk of suicide in certain age groups in the case of women only.

Decoupling of ground level pressures observed in Italian volcanoes: are they driven by space weather geo-effectiveness?

<p>Investigations on correlation drops between near-ground atmospheric pressures measured at sea level and at higher altitudes on Italian volcanoes have been carried out. We looked for perturbations of the atmospheric pressure field driven by volcanic activity, but not excluding possible external triggers for the observed anomalies. Decorrelations between atmospheric pressures measured at Stromboli Island in stations located at different altitudes (years 2002-10) have been analysed and compared with data from other volcanic (Vesuvius) and non volcanic (Mt. Soro) orographic structures. We investigated as their possible triggers volcanic, meteorological and space weather parameters, with particular attention to Total Solar Irradiance (TSI), Kp index and Forbush decreases. Pressure decorrelations seems to be driven by astronomic cycles, with maxima in summer and minima in winter. A further contribution was found, seemingly assignable to TSI anomalies, with correlation minima occurring 12 hours after these but only during phases of high Sun activity. Moreover, during the same phases a main periodicity of about 27 days in pressure decorrelations was revealed by FFT analysis. This period is the same of the Sun Carrington rotation, expressing the periodic reappearance of sunspot groups on Sun’s surface. The strong similarity between recurrences of sunspot number and atmospheric pressure anomalies further supports the role of the former as a possible trigger for the latter.</p>