Dynamic Power Spectral Analysis of Solar Measurements from Photospheric, Chromospheric, and Coronal Sources

An important aspect in the power spectral analysis of solar variability is the quasistationary and quasiperiodic nature of solar periodicities. In other words, the frequency, phase, and amplitude of solar periodicities vary on time scales ranging from active region lifetimes to solar cycle time scales. Here, researchers employ a dynamic, or running, power spectral density analysis to determine many periodicities and their time-varying nature in the projected area of active sunspot groups (S sub act). The Solar Maximum Mission/Active Cavity Radiometer Irradiance Monitor (SMM/ACRIM) total solar irradiance (S), the Nimbus-7 MgII center-to-wing ratio (R (MgII sub c/w)), the Ottawa 10.7 cm flux (F sub 10.7), and the GOES background x ray flux (X sub b) for the maximum, descending, and minimum portions of solar cycle 21 (i.e., 1980 to 1986) are used. The technique dramatically illustrates several previously unrecognized periodicities. For example, a relatively stable period at about 51 days has been found in those indices which are related to emerging magnetic fields. The majority of solar periodicities, particularly around 27, 150 and 300 days, are quasiperiodic because they vary in amplitude and frequency throughout the solar cycle. Finally, it is shown that there are clear differences between the power spectral densities of solar measurements from photospheric, chromospheric, and coronal sources

Disasters and climate change: analyses and methods for projecting future losses from extreme weather

Vellinga, P. [Promotor]Aerts, J.C.J.H. [Promotor

Have disaster losses increased due to anthropogenic climate change?

A number of studies were conducted to demonstrate the best way to assess the potential influence of climate change on disaster losses was to analyze future projections in place of historical data. These studies showed that increases in exposure and wealth were the most important drivers for growing disaster losses. Most of these studies also showed that disaster losses remained constant after normalization, including losses from earthquakes They found that increases after normalization did not fully correct for wealth and population increases, or they identified other sources of exposure increases or vulnerability changes or changing environmental conditions. The analysis of these disaster loss studies showed that economic losses from various weather-related natural hazards, such as storms, tropical cyclones, floods, and small-scale weather events had increased around the globe

Subject to Instability

For Plantier, language constitutes reality and is male dominated. Readers of texts, she says, are at a disadvantage because the author imposes a logic that we must accept in order to understand the text. The discourses shaping our social reality have the same effect. Plantier has struggled against individual voices, discourses, and the very fabric of language informed by these discourses. Subject to Instability examines the impact on her generic evolution of a changing sense of self, of who her interlocutors are, and of those for whom she is speaking. I argue that her increasing attempt to juggle many different voices destabilizes her monologic, poetical voice, resulting in a blurring of generic boundaries and eventually the abandonment of poetry. Recognizing that our entry into language is a form of alienation also unsettles Plantier because it undermines the very identity that allows her to speak for others. She concludes that each woman needs to become a Subject in her own right, but she continues to struggle against dominant discourses, modeling resisting reader strategies. If she can no longer practice monologic steadfastness, this does not deter her from attempting to dismantle patriarchal language and striving to make her voice prevail over others