Physics-based modelling for remote sensing of snow

Remote sensing is the only practicable means to observe snow at large scales. Measurements from passive microwave instruments have been used to derive snow climatology since the late 1970’s, but the algorithms used were limited by the computational power of the era. Simplifications such as the assumption of constant snow properties enabled snow mass to be retrieved from the microwave measurements, but large errors arise from those assumptions, which are still used today. A better approach is to perform retrievals within a data assimilation framework, where a physically-based model of the snow properties can be used to produce the best estimate of the snow cover, in conjunction with multi-sensor observations such as the grain size, surface temperature, and microwave radiation. We have developed an existing snow model, SNOBAL, to incorporate mass and energy transfer of the soil, and to simulate the growth of the snow grains. An evaluation of this model is presented and techniques for the development of new retrieval systems are discussed.

Solar physics: shining a light on solar impacts

Comparing changes in temperature and solar radiation on centennial timescales can help to constrain the Sun’s impact on climate. New findings regarding the minimum activity level of the Sun reveal that comparisons made so far may have been too simplistic.

An examination of the complementary volume–volatility information theories

The volume–volatility relationship during the dissemination stages of information flow is examined by analyzing various theories relating volume and volatility as complementary rather than competing models. The mixture of distributions hypothesis, sequential arrival of information hypothesis, the dispersion of beliefs hypothesis, and the noise trader hypothesis all add to the understanding of how volume and volatility interact for different types of futures traders. An integrated picture of the volume–volatility relationship is provided by investigating the dynamic linear and nonlinear associations between volatility and the volume of informed (institutional) and uninformed (the general public) traders. In particular, the trading behavior explanation for the persistence of futures volatility, the effect of the timing of private information arrival, and the response of institutional traders to excess noise trading risk is examined

Scripture, style and persuasion in seventeenth-century English theories of preaching

The distinction between a Puritan ‘plain’ and a Laudian ‘metaphysical’ preaching style rests on secular rhetorical theories of persuasion that are relatively unimportant to early Stuart homiletics but are central to later Latitudinarian polemics on preaching. Instead, the ‘English Reformed’ theory and method of sermon composition rests on the didactic function of preaching and the need for the Holy Spirit and hearers to co-operate with the preacher. Although Andrewes and some avant-garde conformists questioned this theory, they developed no alternative method of composition. Arguments made in the 1650s for direct inspiration by the Spirit contributed to the decline of both theory and method

Reduced space optimal interpolation of daily rain gauge precipitation in Switzerland

The coarse spacing of automatic rain gauges complicates near-real- time spatial analyses of precipitation. We test the possibility of improving such analyses by considering, in addition to the in situ measurements, the spatial covariance structure inferred from past observations with a denser network. To this end, a statistical reconstruction technique, reduced space optimal interpolation (RSOI), is applied over Switzerland, a region of complex topography. RSOI consists of two main parts. First, principal component analysis (PCA) is applied to obtain a reduced space representation of gridded high- resolution precipitation fields available for a multiyear calibration period in the past. Second, sparse real-time rain gauge observations are used to estimate the principal component scores and to reconstruct the precipitation field. In this way, climatological information at higher resolution than the near-real-time measurements is incorporated into the spatial analysis. PCA is found to efficiently reduce the dimensionality of the calibration fields, and RSOI is successful despite the difficulties associated with the statistical distribution of daily precipitation (skewness, dry days). Examples and a systematic evaluation show substantial added value over a simple interpolation technique that uses near-real-time observations only. The benefit is particularly strong for larger- scale precipitation and prominent topographic effects. Small-scale precipitation features are reconstructed at a skill comparable to that of the simple technique. Stratifying the reconstruction method by the types of weather type classifications yields little added skill. Apart from application in near real time, RSOI may also be valuable for enhancing instrumental precipitation analyses for the historic past when direct observations were sparse.

Understanding stakeholder requirements on an NHS hospital project: application of semiotics-rooted theories.

Hospitals represent complex and difficult contexts for AEC (architecture, engineering and construction) professionals to engage with due to their functional complexity and diversity of stakeholder interests (i.e. patient, visitor, medical specialist). Hospital designers need to take note of changing NHS policy contexts (e.g. the possible empowerment of general practitioners to shape services), technological advances in medical equipment design and the potential health needs of future generations. It is imperative for hospital designers and architects to align their processes and methodologies (e.g. briefing and requirements capture) to the needs and desires of their clients so that a medical facility design is produced which is truly aligned to the requirements of the hospital stakeholders. Semiotics, the “study” or “discipline” of signs aims to investigate the nature of signs (their inception, representation and meaning), whilst semiotics-rooted theories are concerned with investigating how meaning and understanding is mobilized between persons and between organisations. This paper details a semiotics-rooted research approach for investigating the interactions between hospital designers and stakeholders on a forthcoming NHS hospital project in the UK. A semiotics grounded study will potentially provide a deeper understanding of how meaning and understanding is established between hospital project stakeholders and construction professionals.

'Response and Responsibility: Theories of the Implied Reader in Children's Literature Criticism'

Reader Response Theory remains popular within Children's Literature Criticism. It seems to offer a sensible resolution to the question of whether meaning derives from text or reader. Through a close reading of one example of this criticism, I suggest that its dualisms are constantly collapsing into appeals to singular authority. at various stages the text or the reader is wholly responsible for meaning. I further suggest that the criticism bypasses the question of interpretation through claiming knowledge of a child reader whose opinions and reactions can be unproblematically accessed. We do not have to worry about reading texts, because we can, apparently, know the child's response to them with certainty. Anything other than this claim to certainty is taken to be a failure of responsibility, a wallowing in the subjective, obscure and perverse. My intention is to reinstate reading as the responsibility of criticism.