Persistent Decadal-Scale Rainfall Variability in the Tropical South Pacific Convergence Zone Through the Past Six Centuries

Modern Pacific decadal variability (PDV) has global impacts; hence records of PDV from the pre-instrumental period are needed to better inform models that are used to project future climate variability. We focus here on reconstructing rainfall in the western tropical Pacific (Solomon Islands; similar to 9.5 degrees S, similar to 160 degrees E), a region directly influenced by PDV, using cave deposits (stalagmite). A relationship is developed between delta O-18 variations in the stalagmite and local rainfall amount to produce a 600 yr record of rainfall variability from the South Pacific Convergence Zone (SPCZ). We present evidence for large (similar to 1.5 m), abrupt, and periodic changes in total annual rainfall amount on decadal to multidecadal timescales since 1423 +/- 5 CE (Common Era) in the Solomon Islands. The timing of the decadal changes in rainfall inferred from the 20th-century portion of the stalagmite delta O-18 record coincides with previously identified decadal shifts in PDV-related Pacific ocean-atmosphere behavior (Clement et al., 2011; Deser et al., 2004). The Solomons record of PDV is not associated with variations in external forcings, but rather results from internal climate variability. The 600 yr Solomon Islands stalagmite delta O-18 record indicates that decadal oscillations in rainfall are a persistent characteristic of SPCZ-related climate variability.Taiwan ROC NSCNTU 101-2116-M-002-009, 102-2116-M-002-016, 101R7625Geological Science

On the inexplicability of the implicit: differences in the information provided by implicit and explicit tests

Implicit measures are often preferred to overt questioning in many areas of psychology. Their covert nature allows them to circumvent conscious expectations and biases, theoretically providing more objective indicators of people's true attitudes and bel iefs. However, we argue that implicit and explicit measures tap into different memory systems, so that the interpretation of implicit measures is not as straightforward as the interpretation of explicit measures. We conducted an experiment investigating the relation between implicit and explicit measures of person impressions. The results demonstrate that a single stimulus can have opposite effects on implicit and explicit measures, supporting the theory that the measures reflect the contents of different memory systems. We suggest that implicit measures reflect simple associations stored in a "slow-learning" memory system, while explicit measures reflect a combination of these associations with contextually dependent memories stored in a "fast-binding" memory system

The use of national datasets to baseline science education reform: exploring value-added approaches

This paper uses data from the National Pupil Database to investigate the differences in ‘performance’ across the range of science courses available following the 2006 Key Stage 4 (KS4) science reforms in England. This is a value-added exploration (from Key Stage 3 [KS3] to KS4) aimed not at the student or the school level, but rather at that of the course. Different methodological approaches to carrying out such an analysis, ranging from simple non-contextualized techniques, to more complex fully contextualized multilevel models, are investigated and their limitations and benefits are evaluated. Important differences between courses are found in terms of the typical ‘value’ they add to the students studying them with particular applied science courses producing higher mean KS4 outcomes for the same KS3 level compared with other courses. The implications of the emergence of such differences, in a context where schools are judged to a great extent on their value-added performance, are discussed. The relative importance of a variety of student characteristics in determining KS4 outcomes are also investigated. Substantive findings are that across all types of course, science prior attainment at KS3, rather than that of mathematics or English, is the most important predictor of KS4 performance in science, and that students of lower socio-economic status consistently make less progress over KS4 than might be expected, despite prior attainment being accounted for in the modelling

A Note on the Phillips Spectral Framework for Ocean Whitecaps

There has been a recent upsurge in interest in quantifying kinematic, dynamic, and energetic properties of wave breaking in the open ocean, especially in severe sea states. The underpinning observational and modeling framework is provided by the seminal paper of O. M. Phillips. In this note, a fundamental issue contributing to the scatter in results between investigators is highlighted. This issue relates to the choice of the independent variable used in the expression for the spectral density of the mean breaking crest length per unit area. This note investigates the consequences of the different choices of independent variable presently used by various investigators for validating Phillips model predictions for the spectral density of the breaking crest length per unit area and the associated spectral breaking strength coefficient. These spectral measures have a central role in inferring the associated turbulent kinetic energy dissipation rate and the momentum flux to the upper ocean from breaking wave observations

Wave breaking in developing and mature seas

In response to the growing need for robust validation data for Phillips (1985) breaking wave spectral framework, we contribute new field results observed from R/P FLIP for the breaking crest length distributions, Λ, during two different wind-wave conditions, and breaking strength during one wind-wave condition. The first experiment in Santa Barbara Channel had developing seas and the second experiment in the central Pacific Ocean south of Hawaii had mature seas. These are among the first experiments to use dissipation rate measurements probing up into the breaking crest together with simultaneous measurements of breaking crest length distributions. We directly measured the effective breaking strength parameter to be inline image in mature seas with wave age, inline image, of 40–47. We also found that the velocity scale of the breaking dissipation rate peak decreases with increasing wave age. Further, the breaking crest length spectrum falls off slower than the inline image behavior predicted by Phillips (1985). The integrated dissipation rate was consistently higher for mature seas compared to developing seas due to higher energy and momentum fluxes from the wind