Errors and uncertainty in radar estimates of precipitation result both from errors in the basic measurement of reflectivity and from attempts to relate this to the precipitation falling at the ground. If radar data are to be used to their full potential, it is essential that effective measures are taken to mitigate these problems. The automatic processing of radar data that forms part of the UK Met. Office's Nimrod system addresses a number of specific sources of error. These include the identification and removal of spurious echoes resulting from anomalous propagation of the radar beam, errors resulting from variations in the vertical profile of reflectivity and radar sensitivity errors. Routine verification of the surface precipitation estimates has been undertaken, largely through comparison with rain gauge observations, over a range of timescales, which has allowed the benefits of the quality control and correction processes to be quantified. Although the improvement derived varies according to the dominant synoptic situation, an average reduction in the root‐mean‐square difference between gauge and radar data of 30% can be achieved. Copyright © 2000 Royal Meteorological Society

We present initial dual spacecraft observations that for the first time both constrain the spatial scale size and provide spectral properties at medium energies of electron microbursts. We explore individual microburst events that occurred on 2 February 2015 using simultaneous observations made by the twin CubeSats which comprise the National Science Foundation (NSF) Focused Investigations of Relativistic Electron Bursts: Intensity, Range, and Dynamics (FIREBIRD II). During these microburst events, the two identically instrumented FIREBIRD II CubeSats were separated by as little as 11 km while traversing electron precipitation regions in low‐Earth orbit. These coincident microburst events map to size scales >120 km at the equator. Given the prevalence of coincident and noncoincident events we conclude that this is of the same order of magnitude as that of the spatial scale size of electron microburst, an unknown property that is critical for quantifying their overall role in radiation belt dynamics. Finally, we present measurements of electron microbursts showing that precipitation often occurs simultaneously across a broad energy range spanning 200 keV to 1 MeV, a new form of empirical evidence that provides additional insights into the physics of microburst generation mechanisms.

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There is increasing evidence that exposure to stress during development can have sustained effects on animal phenotype and performance across lifehistory stages. For example, developmental stress has been shown to decrease the quality of sexually selected traits (e.g. bird song), and therefore is thought to decrease reproductive success. However, animals exposed to developmental stress may compensate for poor quality sexually selected traits by pursuing alternative reproductive tactics. Here, we examine the effects of developmental stress on adult male reproductive investment and success in the zebra finch (Taeniopygia guttata). We tested the hypothesis that males exposed to developmental stress sire fewer offspring through extra-pair copulations (EPCs), but invest more in parental care. To test this hypothesis, we fed nestlings corticosterone (CORT; the dominant avian stress hormone) during the nestling period and measured their adult reproductive success using common garden breeding experiments. We found that nestlings reared by CORT-fed fathers received more parental care compared with nestlings reared by control fathers. Consequently, males fed CORT during development reared nestlings in better condition compared with control males. Contrary to the prediction that developmental stress decreases male reproductive success, we found that CORT-fed males also sired more offspring and were less likely to rear non-genetic offspring compared with control males, and thus had greater overall reproductive success. These data are the first to demonstrate that developmental stress can have a positive effect on fitness via changes in reproductive success and provide support for an adaptive role of developmental stress in shaping animal phenotype.

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Animals time reprocluctive events to overlap with periocls of favorable environmental conditions. However, weathet conditions can be unpredictable. Young animals may be particularly susceptible to extreme weather during sensitive developmental periods. Here, we investigated the effects of adverse weather conditions on corticosterone levels {a hormone linked to the avian stress resp0nse) and body condition of wild nestling zebra finches (Taeniopygia guttata). We sowght to tease apart the direct versus indirect (i.e. parental) effects of weather on nestling physiology and condition by increasing parental work load with a clutch manipulation experiment. We Found that high temperatures were associated with lower levels of restraint-induced corticosterone and high wind speeds were associated with higher levels of baseline corticosterone. We found no associations between weathet and nestling bocly condition. However, clutch manipulation did affect body condition, with nestlings from experimentally enlarged clutches in worse condition compared to nestlings from experimentally reduced clutches. Our findings suggest that weather can dircctly affect wild nestlings via changes in corticostetonc Ievels. Further research is nceded to understand how changes in corticosterone Ievels affect phenotype and survival in wild nestlings. Understanding how developing animals respond to changes in environmental predictability and extreme weather is vital for unders~anding the p0tential for rapid adaptation in the face of changing climatic conditions. Animals are undcr sclcetion to brecd when cnvironmcntal mnditions are optimal (Visser and Both, 2005). However, weather can be unpredictable and have significant consequences on reproductive outcomes (e.g. Breuner and Hahn, 2003; Martin and Wiehe, 2004). In birds, rainfall, wind, and high or low temperatures can affect nestling development, morphology, body condition, and survival (Conrey et al., 2016; Oberg et al" 2015). Developing animals can be particularly sensitive to perturbations in their environment and developmental effects can have sustained effects on phenotype and fitness across Jifehistory stages and even generations (reviewed in Crino and Breuner, 2015; Monaghan and Haussmann, 2015; Schoech et al" 2011). Consequently, exposure to extreme weather conditions during development could have profound and potentia!Jy long-lasting effects on nestlings via direct and/or indirect mechanisms (i.e. parental effects). Understanding how developing birds respond to extreme weather conditions is of relevance for predicting how they wiJJ cope with rapidly changing global conditions. Although the effects of weather on nestling condition and survival have been we!J described (e.g. Christensen-Dalsgaard et al., 2018; Geiser et al., 2008; Sicurella et al., 2015), the physiological mechanisms that modulate such changes in wild birds are less well-known. The glucocorticoid hormone corticosterone (CORD is an important modulator of the physiological stress response (Romero, 2004) and is thought to be ...

Microplastics have been documented in aquatic and terrestrial ecosystems throughout the world. However, few studies have investigated microplastics in freshwater fish diets. In this study, water samples and three trophic levels of a freshwater food web were investigated for microplastic presence: amphipods (Gammarus lacustris), Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri), and lake trout (Salvelinus namaycush). Microplastics and other anthropogenic materials were documented in water samples, amphipods, and fish, then confirmed using FTIR (Fourier-transform infrared) and Raman spectroscopy. Our findings confirmed the presence of microplastics and other anthropogenic materials in three trophic levels of a freshwater food web in a high-elevation lake in a national park, which corroborates recent studies implicating the global distribution of microplastics. This study further illustrates the need for global action regarding the appropriate manufacturing, use, and disposal of plastics to minimize the effects of plastics on the environment.