The dependence of precipitation and its footprint on atmospheric temperature in idealized extratropical cyclones

Flood hazard is a function of the magnitude and spatial pattern of precipitation accumulation. The sensitivity of precipitation to atmospheric temperature is investigated for idealized extratropical cyclones, enabling us to examine the footprint of extreme precipitation (surface area where accumulated precipitation exceeds high thresholds) and the accumulation in different-sized catchment areas. The mean precipitation increases with temperature, with the mean increase at 5.40%/∘C. The 99.9th percentile of accumulated precipitation increases at 12.7%/∘C for 1 h and 9.38%/∘C for 24 h, both greater than Clausius-Clapeyron scaling. The footprint of extreme precipitation grows considerably with temperature, with the relative increase generally greater for longer durations. The sensitivity of the footprint of extreme precipitation is generally super Clausius-Clapeyron. The surface area of all precipitation shrinks with increasing temperature. Greater relative changes in the number of catchment areas exceeding extreme total precipitation are found when the domain is divided into larger rather than smaller catchment areas. This indicates that fluvial flooding may increase faster than pluvial flooding from extratropical cyclones in a warming world. When the catchment areas are ranked in order of total precipitation, the 99.9th percentile is found to increase slightly above Clausius-Clapeyron expectations for all of the catchment sizes, from 9 km2 to 22,500 km2. This is surprising for larger catchment areas given the change in mean precipitation. We propose that this is due to spatially concentrated changes in extreme precipitation in the occluded fron

On the relationship between hurricane cost and the integrated wind profile

It is challenging to identify metrics that best capture hurricane destructive potential and costs. Although it has been found that the sea surface temperature and vertical wind shear can both make considerable changes to the hurricane destructive potential metrics, it is still unknown which plays a more important role. Here we present a new method to reconstruct the historical wind structure of hurricanes that allows us, for the first time, to calculate the correlation of damage with integrated power dissipation and integrated kinetic energy of all hurricanes at landfall since 1988. We find that those metrics, which include the horizontal wind structure, rather than just maximum intensity, are much better correlated with the hurricane cost. The vertical wind shear over the main development region of hurricanes plays a more dominant role than the sea surface temperature in controlling these metrics and therefore also ultimately the cost of hurricanes

A time delay controller for magnetic bearings

The control of systems with unknown dynamics and unpredictable disturbances has raised some challenging problems. This is particularly important when high system performance needs to be guaranteed at all times. Recently, the Time Delay Control has been suggested as an alternative control scheme. The proposed control system does not require an explicit plant model nor does it depend on the estimation of specific plant parameters. Rather, it combines adaptation with past observations to directly estimate the effect of the plant dynamics. A control law is formulated for a class of dynamic systems and a sufficient condition is presented for control systems stability. The derivation is based on the bounded input-bounded output stability approach using L sub infinity function norms. The control scheme is implemented on a five degrees of freedom high speed and high precision magnetic bearing. The control performance is evaluated using step responses, frequency responses, and disturbance rejection properties. The experimental data show an excellent control performance despite the system complexity

James Baldwin and Ernest Hemingway: The Expatriate Artist as Organic Intellectual

Intellectuals are a class of educated and gifted people (writers, scholars, scientists, artists) produced by society to perform social functions and assume a historical responsibility. Their ethically-based competences and prophetic visions are vital to establishing a sustainable social order and promoting the society of justice. Edward Said wrote in Representations of the Intellectual that “the proliferation of intellectuals has expanded into the very large number of fields in which intellectuals—possibly following on Gramsci’s pioneering suggestions in The Prison Notebooks which almost for the first time saw intellectuals, and not social classes, as pivotal to the workings of modern society—have become the object of study.” To exemplify and understand the role of the intellectual vocation, this paper explores the question of organic intellectualism in famous American expatriate writers Ernest Hemingway and James Baldwin using distinguished public intellectuals such as Edward Said and Cornel West as a conceptual framework and theoretical reference. The discussion raises, among others, the following focus questions: what is an intellectual? What is the role and responsibility of this social class in the public domain? How do intellectuals relate to the marketplace, power, and the marginalized? How do intellectuals contribute to social change? The paper argues that both transatlantic authors Ernest Hemingway and James Baldwin were organic intellectuals whose engaged social critique, intellectual expertise, and activism were designed to counter social dysfunction, injustice, and modern alienation