Zonally elongated areas of cloudiness that make up the east Pacific intertropical convergence zone (ITCZ) can take on several configurations in instantaneous observations. A novel statistical model is used to automatically assess the daily state of the east Pacific ITCZ using infrared satellite images from 1980 to 2012. Four ITCZ states are defined based on ITCZ location relative to the equator: north (nITCZ) and south (sITCZ) of the equator, simultaneously north and south of the equator (dITCZ, for double ITCZ), and over the equator (eITCZ). A fifth ITCZ state is used to classify days when no zonally elongated area of cloudiness is present (aITCZ, for absent ITCZ). The ITCZ states can occur throughout the year (except for the eITCZ, which is not present during June–October), with the nITCZ state dominating in terms of frequency of occurrence. Interannual variability of the state distribution is large. The most striking variability in ITCZ states is observed in spring. During March–April, the dITCZ state occurs on average 34% of the time, second only to the nITCZ state (39%). Composites of observed infrared temperature and precipitation by ITCZ state reveal distinct spatial configurations of cloudiness and rainfall. Strong sea surface temperature anomalies are associated only with eITCZ and sITCZ and they correspond to El Niño and La Niña, respectively. However, all five ITCZ states are associated with distinct atmospheric circulation patterns. A connection is found between the ITCZ and the South Pacific convergence zone (SPCZ), such that activity in the SPCZ is enhanced when the ITCZ is absent in the east Pacific.

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Laboratory prepared and commercial poly(2‐2,2,2‐trifluoroethoxy‐2‐methyl)oxetane, P[3FOx] and poly(2‐2,2,2‐pentafluoropropoxy‐2‐methyl)oxetane, P[5FOx] polyols contain varying amounts of cyclics and low molar mass (LMW) constituents as byproducts of ring opening polymerization. Guided by phase diagrams determined by cloud point measurements, P[3FOx] diol separation is achieved. The impact of purification is explored via the preparation of P[3FOx] and P[5FOx] polyurethanes from cyclic/LMW‐free diols. Mechanical properties are improved because of higher polyurethane molecular weights. AFM revealed complex rugosity that is correlated with dynamic contact angles free from effects of water contamination.

A novel method for moving-target tracking using single-channel synthetic aperture radar (SAR) with a large antenna beamwidth is introduced and evaluated using a field experiment and real SAR data. The presented approach is based on subaperture SAR processing, image statistics, and multitarget unscented Kalman filtering. The method is capable of robustly detecting and tracking moving objects over time, providing information not only about the existence of moving targets but also about their trajectories in the image space while illuminated by the radar beam. We have successfully applied the method on an experimental data set using miniature SAR to accurately characterize the movement of vehicles on a highway section in the radar image space. > Moving target tracking in single-channel, wide-beam SAR < 1 Abstract-A novel method for moving target tracking using single-channel Synthetic Aperture Radar (SAR) with a large antenna beam width is introduced and evaluated using a field experiment and real SAR data. The presented approach is based on sub-aperture SAR processing, image statistics and multitarget unscented Kalman filtering. The method is capable of robustly detecting and tracking moving objects over time, providing information not only about the existence of moving targets but additionally about their trajectories in the image space while illuminated by the radar beam. We have successfully applied the method on an experimental data set using MiSAR to accurately characterize the movement of vehicles on a highway section in the radar image space.

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