Contagion in financial networks

The recent financial crisis has prompted much new research on the interconnectedness of the modern financial system and the extent to which it contributes to systemic fragility. Network connections diversify firms' risk exposures, but they also create channels through which shocks can spread by contagion. We review the extensive literature on this issue, with the focus on how network structure interacts with other key variables such as leverage, size, common exposures, and short-term funding. We discuss various metrics that have been proposed for evaluating the susceptibility of the system to contagion and suggest directions for future research

The Seasonal Cycle and Interannual Variability in Stratospheric Temperatures and Links to the Brewer–Dobson Circulation: An Analysis of MSU and SSU Data

Previous studies have shown that lower-stratosphere temperatures display a near-perfect cancellation between tropical and extratropical latitudes on both annual and interannual time scales. The out-of-phase relationship between tropical and high-latitude lower-stratospheric temperatures is a consequence of variability in the strength of the Brewer–Dobson circulation (BDC). In this study, the signal of the BDC in stratospheric temperature variability is examined throughout the depth of the stratosphere using data from the Stratospheric Sounding Unit (SSU). While the BDC has a seemingly modest signal in the annual cycle in zonal-mean temperatures in the mid- and upper stratosphere, it has a pronounced signal in the month-to-month and interannual variability. Tropical and extratropical temperatures are significantly negatively correlated in all SSU channels on interannual time scales, suggesting that variations in wave driving are a major factor controlling global-scale temperature variability not only in the lower stratosphere (as shown in previous studies), but also in the mid- and upper stratosphere. The out-of-phase relationship between tropical and high latitudes peaks at all levels during the cold-season months: December–March in the Northern Hemisphere and July–October in the Southern Hemisphere. In the upper stratosphere, the out-of-phase relationship with high-latitude temperatures extends beyond the tropics and well into the extratropics of the opposite hemisphere. The seasonal cycle in stratospheric temperatures follows the annual march of insolation at all levels and latitudes except in the mid- to upper tropical stratosphere, where it is dominated by the semiannual oscillation. M

Domain Growth in Random Magnets

We study the kinetics of domain growth in ferromagnets with random exchange interactions. We present detailed Monte Carlo results for the nonconserved random-bond Ising model, which are consistent with power-law growth with a variable exponent. These results are interpreted in the context of disorder barriers with a logarithmic dependence on the domain size. Further, we clarify the implications of logarithmic barriers for both nonconserved and conserved domain growth.Comment: 7 pages, 4 figure

Interannual variability of tropospheric composition:the influence of changes in emissions, meteorology and clouds

We have run a chemistry transport model (CTM) to systematically examine the drivers of interannual variability of tropospheric composition during 1996-2000. This period was characterised by anomalous meteorological conditions associated with the strong El Nino of 1997-1998 and intense wildfires, which produced a large amount of pollution. On a global scale, changing meteorology (winds, temperatures, humidity and clouds) is found to be the most important factor driving interannual variability of NO2 and ozone on the timescales considered. Changes in stratosphere-troposphere exchange, which are largely driven by meteorological variability, are found to play a particularly important role in driving ozone changes. The strong influence of emissions on NO2 and ozone interannual variability is largely confined to areas where intense biomass burning events occur. For CO, interannual variability is almost solely driven by emission changes, while for OH meteorology dominates, with the radiative influence of clouds being a very strong contributor. Through a simple attribution analysis for 1996-2000 we conclude that changing cloudiness drives 25% of the interannual variability of OH over Europe by affecting shortwave radiation. Over Indonesia this figure is as high as 71%. Changes in cloudiness contribute a small but non-negligible amount (up to 6%) to the interannual variability of ozone over Europe and Indonesia. This suggests that future assessments of trends in tropospheric oxidizing capacity should account for interannual variability in cloudiness, a factor neglected in many previous studies

Surficial Geology of the Bluffton (Iowa) 7.5\u27\u27 Quadrangle,

https://ir.uiowa.edu/igs_ofm/1046/thumbnail.jp