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Flatau, PJ, Draine BT.  2012.  Fast near field calculations in the discrete dipole approximation for regular rectilinear grids. Optics Express. 20:1247-1252.   10.1364/OE.20.001247   AbstractWebsite

A near-field calculation of light electric field intensity inside and in the vicinity of a scattering particle is discussed in the discrete dipole approximation. A fast algorithm is presented for gridded data. This algorithm is based on one matrix times vector multiplication performed with the three dimensional fast Fourier transform. It is shown that for moderate and large light scattering near field calculations the computer time required is reduced in comparison to some of the other methods. (C) 2012 Optical Society of America

Flatau, PJ.  2004.  Fast solvers for one dimensional light scattering in the discrete dipole approximation. Optics Express. 12:3149-3155.   10.1364/OPEX.12.003149   AbstractWebsite

In this paper we propose new algorithms for solution of light scattering on non-spherical particles using one-dimensional variant of discrete dipole approximation. We discuss recent advances in algorithms for matrices with structures in context of the discrete dipole approximation and show that it is possible to apply these advances to form non-iterative solvers and improve algorithmic complexity in case of many incoming plane parallel waves. (C) 2004 Optical Society of America.

Flatau, M, Flatau PJ, Phoebus P, Niller PP.  1997.  The feedback between equatorial convection and local radiative and evaporative processes: The implications for intraseasonal oscillations. Journal of the Atmospheric Sciences. 54:2373-2386.   10.1175/1520-0469(1997)054<2373:tfbeca>2.0.co;2   AbstractWebsite

Existing theories of the Madden-Julian oscillation neglect the feedback between the modification of sea surface temperature by the convection and development of a convective cluster itself. The authors show that the convection-generated SST gradient plays an important role in cluster propagation and development. The relative importance of radiative and evaporative fluxes in SST regulation is also discussed. Various Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment and Central Equatorial Pacific Experiment observation platforms are used to estimate the effects of equatorial convection on SST changes during March 1993. The data include drifting buoys and TAO-buoy array measurements, combined with the Navy Operational Global Atmospheric Prediction System analyzed surface wind fields and Geostationary Meteorological Satellite cloud-top temperatures. It is shown that during the equatorial convection episode SST is decreasing under and to the west of the convective heat source due to the large wind velocities and solar flux reduction. To the east of the source, in the convergence region of a Kelvin wave, low wind speeds and high insolation cause the SST to increase. The data are used to formulate an empirical relationship between wind speed and the 24-h SST change on the equator. Although formulated in terms of wind speed, this relationship implicitly includes radiative effects. This equation is then used in a global circulation model to examine the effect of SST feedback on the behavior of equatorial convection. A series of experiments is performed using an R15 general circulation model of the ''aquaplanet'' with a zonally symmetric SST distribution. In the case with fixed SSTs, equatorial wind fluctuations have the character of waves propagating around the globe with a phase speed of about 20 m s(-1). When the effect of SST modification is included, the fluctuations slow down and become more organized. In addition, a 40-60-day peak appears in the spectral analysis of equatorial precipitation.