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Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere – the “global carbon budget” – is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (EFF) are based on energy statistics and cement production data, while emissions from land use change (ELUC), mainly deforestation, are based on land use and land use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly and its growth rate (GATM) is computed from the annual changes in concentration. The ocean CO2 sink (SOCEAN) and terrestrial CO2 sink (SLAND) are estimated with global process models constrained by observations. The resulting carbon budget imbalance (BIM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as ±1σ. For the last decade available (2009–2018), EFF was 9.5±0.5 GtC yr−1, ELUC 1.5±0.7 GtC yr−1, GATM 4.9±0.02 GtC yr−1 (2.3±0.01 ppm yr−1), SOCEAN 2.5±0.6 GtC yr−1, and SLAND 3.2±0.6 GtC yr−1, with a budget imbalance BIM of 0.4 GtC yr−1 indicating overestimated emissions and/or underestimated sinks. For the year 2018 alone, the growth in EFF was about 2.1 % and fossil emissions increased to 10.0±0.5 GtC yr−1, reaching 10 GtC yr−1 for the first time in history, ELUC was 1.5±0.7 GtC yr−1, for total anthropogenic CO2 emissions of 11.5±0.9 GtC yr−1 (42.5±3.3 GtCO2). Also for 2018, GATM was 5.1±0.2 GtC yr−1 (2.4±0.1 ppm yr−1), SOCEAN was 2.6±0.6 GtC yr−1, and SLAND was 3.5±0.7 GtC yr−1, with a BIM of 0.3 GtC. The global atmospheric CO2 concentration reached 407.38±0.1 ppm averaged over 2018. For 2019, preliminary data for the first 6–10 months indicate a reduced growth in EFF of +0.6 % (range of −0.2 % to 1.5 %) based on national emissions projections for China, the USA, the EU, and India and projections of gross domestic product corrected for recent changes in the carbon intensity of the economy for the rest of the world. Overall, the mean and trend in the five components of the global carbon budget are consistently estimated over the period 1959–2018, but discrepancies of up to 1 GtC yr−1 persist for the representation of semi-decadal variability in CO2 fluxes. A detailed comparison among individual estimates and the introduction of a broad range of observations shows (1) no consensus in the mean and trend in land use change emissions over the last decade, (2) a persistent low agreement between the different methods on the magnitude of the land CO2 flux in the northern extra-tropics, and (3) an apparent underestimation of the CO2 variability by ocean models outside the tropics. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding of the global carbon cycle compared with previous publications of this data set (Le Quéré et al., 2018a, b, 2016, 2015a, b, 2014, 2013). The data generated by this work are available at https://doi.org/10.18160/gcp-2019 (Friedlingstein et al., 2019).

Introgression among parasite species has the potential to transfer traits of biomedical importance across species boundaries. The parasitic blood fluke Schistosoma haematobium causes urogenital schistosomiasis in humans across sub-Saharan Africa. Hybridization with other schistosome species is assumed to occur commonly, because genetic crosses between S. haematobium and livestock schistosomes, including S. bovis, can be staged in the laboratory, and sequencing of mtDNA and rDNA amplified from microscopic miracidia larvae frequently reveals markers from different species. However the frequency, direction, age and genomic consequences of hybridization are unknown. We hatched miracidia from eggs, and sequenced the exomes from 96 individual S. haematobium miracidia from infected patients from Niger and the Zanzibar archipelago. These data revealed no evidence for contemporary hybridization between S. bovis and S. haematobium in our samples. However, all Nigerien S. haematobium genomes sampled show hybrid ancestry, with 3.3-8.2% of their nuclear genomes derived from S. bovis, providing evidence of an ancient, introgression event that occurred at least 108-613 generations ago. Some S. bovis derived alleles have spread to high frequency or reached fixation and show strong signatures of directional selection; the strongest signal spans a single gene in the invadolysin gene family (Chr. 4). Our results suggest that S. bovis/S. haematobium hybridization occurs rarely, but demonstrate profound consequences of ancient introgression from a livestock parasite into the genome of S. haematobium, the most prevalent schistosome species infecting humans.

When designing a new radar system, standard resolution trade-offs play a major role, providing the basic parameters of the radar, such as size, update rate, and range. Besides, diversity has long been used for mitigating fading effects due to the fluctuation of targets and clutter. However, with the arrival of more flexible systems, using multiple parallel channels on transmit and receive, and wider instantaneous bandwidths, these standard trade-offs are becoming less simple—and more flexible. In this communication, we will analyse the benefits of diversity and its relations with range, Doppler, and angle, for detection and location of moving targets with wideband/wide-beam radar systems. The idea is to contribute to a better understanding of the real benefits of agile transmissions for detection/localization of moving targets, focusing on range, velocity, and angular measurement improvements, as well as on the benefits for detection of moving targets. Special attention will be given to the quality of the different wideband wide-beam sensor modes for long-range surveillance, and new results on detection of moving targets in clutter will be provided to demonstrate the effectiveness of these new architectures for small target detection at long range, in difficult environments.

Adult schistosomes live in the blood vessels and cannot easily be sampled from humans, so archived miracidia larvae hatched from eggs expelled in feces or urine are commonly used for population genetic studies. Large collections of archived miracidia on FTA cards are now available through the Schistosomiasis Collection at the Natural History Museum (SCAN). Here we describe protocols for whole genome amplification of Schistosoma mansoni and Schistosome haematobium miracidia from these cards, as well as real time PCR quantification of amplified schistosome DNA. We used microgram quantities of DNA obtained for exome capture and sequencing of single miracidia, generating dense polymorphism data across the exome. These methods will facilitate the transition from population genetics, using limited numbers of markers to population genomics using genome-wide marker information, maximising the value of collections such as SCAN.

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In this paper the influence of clutter power spectrum on unambiguous radar target detection with single low pulse repetition frequency wideband waveform is analyzed. Impact of both stationary and diffuse clutter components for different signal bandwidths and coherent processing intervals (CPI) is studied. Exponential model of the ground clutter power spectrum for the diffuse component is used. For the first time, radar detection performance for wideband signals at ambiguous to clutter velocities is predicted as function of bandwidth and CPI.

In this paper the problem of unambiguous target detection with wideband radar is discussed. A range migration phenomenon is used to resolve Doppler ambiguities present in low pulse repetition frequency mode. Iterative Adaptive Approach is applied to solve this problem and shown to be an attractive solution. Capability of the proposed processing is shown via numerical simulations. Experimental data sets demonstrate 25 dB improvement in detection performance of a moving target at the first blind velocity.

One of the most striking challenges that radar designers have to deal with, when developing new doppler systems, is to overcome the difficulty of working with ambiguous velocities. Even using high PRF’s, target’s velocities become ambiguous because wavelengths are getting shorter. This article tries to depict an idea of becoming unambiguous in doppler, using only one PRF and without range tracking, taking advantage of target’s range migration if high range resolution radars are used. Simulations will be shown justifying the idea, but also, pointing out some limitations depending on the radar’s operational parameters and target’s relative motion.

This paper describes an analytical model of the full-polarimetric sea surface scattering and Doppler signature. The model combines the small-slope-approximation theory (at the second order) with a weak nonlinear sea surface representation. Such a model is used to examine the variation of the Doppler central frequency/bandwidth and of the normalized radar cross section as function of wind speed and direction. The results suggest that the model can be a valuable tool for the accurate observation of sea surface currents.

Wideband radars are sensors of new generation used for target detection and classification. Detection of moving targets with wideband radar faces range migration phenomenon which is used to resolve velocity ambiguities in low pulse repetition frequency mode. The resolution is equivalent to a bi-dimensional spectrum estimation problem with non-uniform sampling, while the ability to resolve velocity ambiguity depends on spectral resolution of the method used. Recently Iterative Adaptive Approach (IAA) was shown an attractive solution of this problem. Nevertheless straightforward implementation of IAA for wideband signal suffers from high computational requirements. In this paper fast implementation of IAA for wideband data is proposed and studied with numerical simulations. Proposed solution decreases computational cost by an order of magnitude for realistic data sizes.