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KEK. The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies ${\sim}0.8$ GeV. The differential measurements are presented as a function of muon and pion kinematics, in the restricted phase-space defined by $p_{\pi^+} > 200$ MeV/c, $p_{\mu^-} > 200$ MeV/c, $\cos\theta_{\pi^+} > 0.3$ and $\cos\theta_{\mu^-} > 0.3$. The total flux integrated $\nu_\mu$ charged current single positive pion production cross section on water in the restricted phase-space is measured to be $\langle\sigma\rangle_\phi=4.25\pm0.48~(\mathrm{stat})\pm1.56~(\mathrm{syst})\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$. Data points taken from attached tar file available at http://t2k-experiment.org/results/. Unfolded $\nu_\mu$ CC1$\pi^+$ differential cross section as a function of $p_\pi$ in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$.

Super-Kamiokande. A comprehensive study on the atmospheric neutrino flux in the energy region from sub-GeV up to several TeV using the Super-Kamiokande water Cherenkov detector is presented in this paper. The energy and azimuthal spectra of the atmospheric ${\nu}_e+{\bar{\nu}}_e$ and ${\nu}_{\mu}+{\bar{\nu}}_{\mu}$ fluxes are measured. The energy spectra are obtained using an iterative unfolding method by combining various event topologies with differing energy responses. The azimuthal spectra depending on energy and zenith angle, and their modulation by geomagnetic effects, are also studied. A predicted east-west asymmetry is observed in both the ${\nu}_e$ and ${\nu}_{\mu}$ samples at 8.0 ${\sigma}$ and 6.0 ${\sigma}$ significance, respectively, and an indication that the asymmetry dipole angle changes depending on the zenith angle was seen at the 2.2 ${\sigma}$ level. The measured energy and azimuthal spectra are consistent with the current flux models within the estimated systematic uncertainties. A study of the long-term correlation between the atmospheric neutrino flux and the solar magnetic activity cycle is also performed, and a weak indication of a correlation was seen at the 1.1 ${\sigma}$ level, using SK I-IV data spanning a 20 year period. For particularly strong solar activity periods known as Forbush decreases, no theoretical prediction is available, but a deviation below the typical neutrino event rate is seen at the 2.4 ${\sigma}$ level. Muon neutrino flux measured by SK I-IV data. Error written in percentage including both statistical and systematic uncertainties.

Super-Kamiokande. A comprehensive study on the atmospheric neutrino flux in the energy region from sub-GeV up to several TeV using the Super-Kamiokande water Cherenkov detector is presented in this paper. The energy and azimuthal spectra of the atmospheric ${\nu}_e+{\bar{\nu}}_e$ and ${\nu}_{\mu}+{\bar{\nu}}_{\mu}$ fluxes are measured. The energy spectra are obtained using an iterative unfolding method by combining various event topologies with differing energy responses. The azimuthal spectra depending on energy and zenith angle, and their modulation by geomagnetic effects, are also studied. A predicted east-west asymmetry is observed in both the ${\nu}_e$ and ${\nu}_{\mu}$ samples at 8.0 ${\sigma}$ and 6.0 ${\sigma}$ significance, respectively, and an indication that the asymmetry dipole angle changes depending on the zenith angle was seen at the 2.2 ${\sigma}$ level. The measured energy and azimuthal spectra are consistent with the current flux models within the estimated systematic uncertainties. A study of the long-term correlation between the atmospheric neutrino flux and the solar magnetic activity cycle is also performed, and a weak indication of a correlation was seen at the 1.1 ${\sigma}$ level, using SK I-IV data spanning a 20 year period. For particularly strong solar activity periods known as Forbush decreases, no theoretical prediction is available, but a deviation below the typical neutrino event rate is seen at the 2.4 ${\sigma}$ level. Electron neutrino flux measured by SK I-IV data. Error written in percentage including both statistical and systematic uncertainties.

KEK. The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies ${\sim}0.8$ GeV. The differential measurements are presented as a function of muon and pion kinematics, in the restricted phase-space defined by $p_{\pi^+} > 200$ MeV/c, $p_{\mu^-} > 200$ MeV/c, $\cos\theta_{\pi^+} > 0.3$ and $\cos\theta_{\mu^-} > 0.3$. The total flux integrated $\nu_\mu$ charged current single positive pion production cross section on water in the restricted phase-space is measured to be $\langle\sigma\rangle_\phi=4.25\pm0.48~(\mathrm{stat})\pm1.56~(\mathrm{syst})\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$. Data points taken from attached tar file available at http://t2k-experiment.org/results/. Unfolded $\nu_\mu$ CC1$\pi^+$ differential cross section as a function of $\cos\theta_{\mu,\pi}$ in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$.

This article deals with surface loss on quartz of atomic hydrogen (H) and its isotope deuterium(D) in a low-pressure (10 Pa) pulsed inductively coupled plasma. The atomic temporal decayin the post discharge is measured by two-photon absorption laser-induced fluorescence(TALIF). From the loss rate, the atomic surface loss probability is determined. In purehydrogen or pure deuterium gas, no isotopic effect on surface kinetics has been observed andthe surface loss probabilities of H and D were found to be almost identical and equal to∼1.8%. However, despite the lack of difference in surface loss probability, a net isotopic effecton surface loss rate due to the mass difference between the isotopes is measured. Hydrogenatoms diffuse faster and have higher flux to the plasma chamber walls than deuterium atoms.Hydrogen atoms are therefore lost at higher rate than deuterium atoms. Based on the observedisotopic difference and on the comparison between H and D TALIF signals, the isotopiceffects on H and D atom production are discussed.

Narrowing uncertainties about carbon cycling is important in the Arctic where rapid environmental changes contribute to enhanced mobilization of carbon. Here we quantify soil organic carbon (SOC) contents of permafrost soils along the Yukon Coastal Plain and determine the annual fluxes from erosion. Different terrain units are assessed based on surficial geology, morphology, and ground ice conditions. To account for the volume of wedge ice and massive ice in a unit, sample SOC contents are reduced by 19% and sediment contents by 16%. The SOC content in a 1 m**2 column of soil varies according to the height of the bluff, ranging from 30 to 662 kg, with a mean value of 183 kg. Forty-four per cent of the SOC is within the top 1 m of soil and values vary based on surficial materials, ranging from 30 to 53 kg C/m**3, with a mean of 41 kg. Eighty per cent of the shoreline is erosive with a mean annual rate of change is 0.7 m/a. This results in a SOC flux per meter of shoreline of 131 kg C/m/a, and a total flux for the entire Yukon coast of 35.5 10**6 kg C/a (0.036 Tg C/a). The mean flux of sediment per meter of shoreline is 5.3 10**3 kg/m/a, with a total flux of 1,832.0 10**6 kg/a (1.832 Tg/a). Sedimentation rates indicate that approximately 13% of the eroded carbon is sequestered in nearshore sediments, where the overwhelming majority of organic carbon is of terrestrial origin. Supplement to: Couture, Nicole; Irrgang, Anna Maria; Pollard, Wayne H; Lantuit, Hugues; Fritz, Michael (2018): Coastal Erosion of Permafrost Soils Along the Yukon Coastal Plain and Fluxes of Organic Carbon to the Canadian Beaufort Sea. Journal of Geophysical Research: Biogeosciences

Rapid changes in ocean circulation and climate have been observed in marine-sediment and ice cores over the last glacial period and deglaciation, highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing. To date, these rapid changes in climate and ocean circulation are still not fully explained. One obstacle hindering progress in our understanding of the interactions between past ocean circulation and climate changes is the difficulty of accurately dating marine cores. Here, we present a set of 92 marine sediment cores from the Atlantic Ocean for which we have established age-depth models that are consistent with the Greenland GICC05 ice core chronology, and computed the associated dating uncertainties, using a new deposition modeling technique. This is the first set of consistently dated marine sediment cores enabling paleoclimate scientists to evaluate leads/lags between circulation and climate changes over vast regions of the Atlantic Ocean. Moreover, this data set is of direct use in paleoclimate modeling studies.

Based on the nitrous oxide (N2O) emission model developed by Maavara et al. (2019, GCB) and the HydroLAKES database, we simulated the average annual N2O emissions from 1.4 million lakes and reservoirs. We give bounded estimates of N2O emissions based on emission factors of 0.3%, 0.9% and 1.5%. We have gridded the model outputs at a resolution of 0.5 degree (i.e. ~50 km), and report emission fluxes normalized by total grid cell area. In addition, we report the areal proportion of lakes and reservoirs, which can be used to transform these emission estimates into N2O emission rates per water surface area. All estimates are reported for four types of standing water bodies: 0) All lakes and reservoirs, 1) Natural lakes w/o dam constructions, 2) Reservoirs, and 3) Regulated lakes. This classification of lake types was directly adopted from the HydroLAKES database. Supplement to: Lauerwald, Ronny; Regnier, Pierre; Figueiredo, Viviane; Enrich-Prast, Alex; Bastviken, David; Lehner, Bernhard; Maavara, Taylor; Raymond, Peter (2019): Natural Lakes Are a Minor Global Source of N₂O to the Atmosphere. Global Biogeochemical Cycles, 33(12), 1564-1581

KEK. The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies ${\sim}0.8$ GeV. The differential measurements are presented as a function of muon and pion kinematics, in the restricted phase-space defined by $p_{\pi^+} > 200$ MeV/c, $p_{\mu^-} > 200$ MeV/c, $\cos\theta_{\pi^+} > 0.3$ and $\cos\theta_{\mu^-} > 0.3$. The total flux integrated $\nu_\mu$ charged current single positive pion production cross section on water in the restricted phase-space is measured to be $\langle\sigma\rangle_\phi=4.25\pm0.48~(\mathrm{stat})\pm1.56~(\mathrm{syst})\times10^{-40}~\mathrm{cm}^{2}/\mathrm{nucleon}$. Data points taken from attached tar file available at http://t2k-experiment.org/results/. Total $\nu_\mu$ CC1$\pi^+$ cross section on water in the reduced phase-space of $p_{\pi^+} > 200$ MeV/$c$, $p_\mu > 200$ MeV/c, $\cos(\theta_{\pi^+}) > 0.3$ and $\cos(\theta_\mu) > 0.3$. The T2K data point is placed at the $\nu_\mu$ flux mean energy.