Hongwoo Kwon

© Author 2014.We use a 3-D regional atmospheric chemistry transport model to examine ozone dry deposition in East Asia, which is an important but uncertain research area because of insufficient observation and numerical studies focusing on East Asia. Here we compare two widely used dry deposition parameterization schemes, the Wesely and M3DRY schemes, which are used in the WRF-Chem and Community Multiscale Air Quality models, respectively. Simulated ozone dry deposition velocities with the two schemes under identical meteorological conditions show considerable differences owing to surface resistance parameterization discrepancies. Resulting ozone concentrations differ by up to 10 ppbv for a monthly mean in May when the peak ozone typically occurs in East Asia. An evaluation of the simulated dry deposition velocities shows that the Wesely scheme calculates values with more pronounced diurnal variation than the M3DRY and results in a good agreement with the observations. However, we find significant changes in simulated ozone concentrations using the Wesely scheme but with different surface type data sets, indicating the high sensitivity of ozone deposition calculations to the input data. The need is high for observations to constrain the dry deposition parameterization and its input data to improve the use of air quality models for East Asia.

In this paper, I develop and defend a novel account of Moore’s paradox, which locates its source in self-reference. The main insight comes from Gareth Evans’s discussion of Transparency, which says that a normal person takes p to be directly relevant to the truth of “I believe that p.” It has been noticed by many philosophers that Moore’s paradox is closely related to Evans’s Transparency. However, Evans’s claim that Transparency is constitutively related to self-reference has received relatively little attention from those philosophers. I claim that once we get the two links straight and join them, a novel and plausible account of Moore’s paradox emerges. According to this account, the absurdity involved in Moore’s paradox is traceable to a constitutive relation between Transparency and self-reference. Asserting “p but I do not believe that p” sounds absurd, because the use of “I” indicates that the subject thinks of the individual referred to as herself, while her failing to conform to Transparency implies the opposite.

There are close parallels between Frank Jackson's case of black-and-white Mary and David Lewis's case of the two omniscient gods. This essay develops and defends what may be called “the ability hypothesis” about the knowledge that the gods lack, by adapting Lewis's ability hypothesis about the knowledge that Mary acquires. What the gods might lack despite their propositional omniscience is not any distinctive kind of information, but certain abilities of introspection. The motivating idea is that knowledge one acquires by exercising introspective abilities cannot fail to be knowledge about oneself or indexical knowledge. So in order to envisage the gods' epistemic situation coherently, we need to assume that they lack those introspective abilities. But once we recognize that, it turns out that positing a special kind of information is a gratuitous addition. The two gods' ignorance simply consists in their lack of introspective abilities.