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Timeline of Marni Pazos

2017
Nov
08
Published new article






Identification of moisture sources in the Atlantic Ocean for cyclogenesis processes

Published: 08 November 2017 by MDPI AG in First International Electronic Conference on the Hydrological Cycle

doi: 10.3390/CHyCle-2017-04862

<p>We used the Lagrangian model FLEXPART to identify the moisture sources of 110 tropical cyclones with cyclogenesis within an area comprised between 15 &ndash; 45 W and 8 &ndash; 20 N. The model computes changes in the specific humidity from a 10-day period before the day of cyclogenesis of each tropical cyclone is and its contribution to the moisture budget of the region of interest. We calculated the values of the anomalies of the moisture budget to identify the main regions of moisture sources: the African coasts in the North Atlantic, the continental region over western Africa and along the South African coast. We also calculated the contribution of moisture sources from the South Atlantic to the cyclogenesis. The frequency distribution of these percentages shows two main peaks, one in ~20% and other in ~50%. The result shows that the path of tropical cyclones with ~50% of moisture contribution from the South Atlantic made landfall more often than those with ~20%.&nbsp;&nbsp;</p>

11 Reads | 0 Citations
2016
Dec
01
Published new article




Article

New perspectives on contributing factors to the monthly behavior of the aa geomagnetic index

Published: 01 December 2016 by Springer Nature in Earth, Planets and Space

doi: 10.1186/s40623-016-0569-z

We studied the Aa geomagnetic index (aa index daily average) behavior on a monthly timescale using data from 1868 to 2015 for cycles 11–24. We identified solar- and lunar-associated periodicities in the Aa time series and found statistically significant Aa minima values a few days before the full Moon and high Aa values during the new Moon. When considering all the cycles, it was clear that the deepest Aa minima occurred during the Aa descending activity phase. However, when the cycles were separated according to the direction of the interplanetary magnetic field (IMF), the Aa minima came from the contribution of cycles with the IMF pointing toward the Sun (Type 1). Furthermore, during the descending phase of cycles with the IMF pointing away from the Sun (Type 2), the smallest Aa index values were found along with smaller changes compared to Type 1 cases. This behavior implies that during Type 1 cycles there are larger Aa perturbations than during Type 2 cycles. It is very likely that the mechanisms responsible for the Aa monthly behavior are a combination of solar and lunar effects that depend on several factors: (a) the Moon phases (new and full Moon), (b) the phase of the solar cycle (ascending or descending), and (c) the direction of the interplanetary magnetic field (away or toward the Sun). Keywords Moon Geomagnetic activity aa index Solar activity Interplanetary magnetic field

2 Reads | 0 Citations
2016
Jul
15
Published new article






Moisture Sources Identification of Tropical Cyclones in the North Atlantic

Published: 15 July 2016 by MDPI AG in The 1st International Electronic Conference on Atmospheric Sciences

doi: 10.3390/ecas2016-E001

<p>In this study, we identified the moisture sources of 110 tropical cyclones with cyclogenesis within the area comprised between 15&ndash;45&deg;W and 8&ndash;20&deg;N. We used the Lagrangian FLEXPART model to perform the analysis that computes the changes in the specific humidity of ten days before the day of cyclogenesis of each tropical cyclone and its contribution to the moisture budget of the region of interest. Then we calculated the anomaly values of the results to identify the main regions of moisture sources: The African coasts in the North Atlantic, the continental region over western Africa and the area along the South Atlantic from the Equator to the Southern Africa coast.</p>

14 Reads | 0 Citations
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