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英国资助人工智能项目助力工业减排 快报文章
气候变化快报,2023年第17期
作者:  王田宇 刘燕飞
Microsoft Word(15Kb)  |  收藏  |  浏览/下载:547/1  |  提交时间:2023/09/05
AI for Decarbonisation  Decarbonisation Applications  Hydrogen Energy Management  Building Energy Efficiency  Open-Source Forecasting Model  
Population flow drives spatio-temporal distribution of COVID-19 in China 期刊论文
NATURE, 2020
作者:  Fernandez, Diego Carlos;  Komal, Ruchi;  Langel, Jennifer;  Ma, Jun;  Duy, Phan Q.;  Penzo, Mario A.;  Zhao, Haiqing;  Hattar, Samer
收藏  |  浏览/下载:85/0  |  提交时间:2020/07/03

Sudden, large-scale and diffuse human migration can amplify localized outbreaks of disease into widespread epidemics(1-4). Rapid and accurate tracking of aggregate population flows may therefore be epidemiologically informative. Here we use 11,478,484 counts of mobile phone data from individuals leaving or transiting through the prefecture of Wuhan between 1 January and 24 January 2020 as they moved to 296 prefectures throughout mainland China. First, we document the efficacy of quarantine in ceasing movement. Second, we show that the distribution of population outflow from Wuhan accurately predicts the relative frequency and geographical distribution of infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) until 19 February 2020, across mainland China. Third, we develop a spatio-temporal '  risk source'  model that leverages population flow data (which operationalize the risk that emanates from epidemic epicentres) not only to forecast the distribution of confirmed cases, but also to identify regions that have a high risk of transmission at an early stage. Fourth, we use this risk source model to statistically derive the geographical spread of COVID-19 and the growth pattern based on the population outflow from Wuhan  the model yields a benchmark trend and an index for assessing the risk of community transmission of COVID-19 over time for different locations. This approach can be used by policy-makers in any nation with available data to make rapid and accurate risk assessments and to plan the allocation of limited resources ahead of ongoing outbreaks.


Modelling of population flows in China enables the forecasting of the distribution of confirmed cases of COVID-19 and the identification of areas at high risk of SARS-CoV-2 transmission at an early stage.


  
Hydrothermal (NN)-N-15-N-15 abundances constrain the origins of mantle nitrogen 期刊论文
NATURE, 2020, 580 (7803) : 367-+
作者:  Zhao, Steven;  Jang, Cholsoon;  Liu, Joyce;  Uehara, Kahealani;  Gilbert, Michael;  Izzo, Luke;  Zeng, Xianfeng;  Trefely, Sophie;  Fernandez, Sully;  Carrer, Alessandro;  Miller, Katelyn D.;  Schug, Zachary T.;  Snyder, Nathaniel W.;  Gade, Terence P.;  Titchenell, Paul M.;  Rabinowitz, Joshua D.;  Wellen, Kathryn E.
收藏  |  浏览/下载:34/0  |  提交时间:2020/05/13

Nitrogen is the main constituent of the Earth'  s atmosphere, but its provenance in the Earth'  s mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth'  s accretion versus that subducted from the Earth'  s surface is unclear(1-6). Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare (NN)-N-15-N-15 isotopologue of N-2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle delta N-15 (the fractional difference in N-15/N-14 from air), N-2/Ar-36 and N-2/He-3. Our results show that negative delta N-15 values observed in gases, previously regarded as indicating a mantle origin for nitrogen(7-10), in fact represent dominantly air-derived N-2 that experienced N-15/N-14 fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the (NN)-N-15-N-15 data allow extrapolations that characterize mantle endmember delta N-15, N-2/Ar-36 and N-2/He-3 values. We show that the Eifel region has slightly increased delta N-15 and N-2/Ar-36 values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts(11), consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has delta N-15 values substantially greater than that of the convective mantle, resembling surface components(12-15), its N-2/Ar-36 and N-2/He-3 ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume delta N-15 values may both be dominantly primordial features.


  
Backward Probability Model for Identifying Multiple Contaminant Source Zones Under Transient Variably Saturated Flow Conditions 期刊论文
WATER RESOURCES RESEARCH, 2020, 56 (4)
作者:  Hwang, Hyoun-Tae;  Jeen, Sung-Wook;  Kaown, Dugin;  Lee, Seong-Sun;  Sudicky, Edward A.;  Steinmoeller, Derek T.;  Lee, Kang-Kun
收藏  |  浏览/下载:21/0  |  提交时间:2020/07/02
backward probability model  source zone identifications  transient flow  vadose zone  uncertainty analysis  HydroGeoSphere  
Constraint on the matter-antimatter symmetry-violating phase in neutrino oscillations 期刊论文
NATURE, 2020, 580 (7803) : 339-+
作者:  Houben, Lothar;  Weissman, Haim;  Wolf, Sharon G.;  Rybtchinski, Boris
收藏  |  浏览/下载:30/0  |  提交时间:2020/07/03

The charge-conjugation and parity-reversal (CP) symmetry of fundamental particles is a symmetry between matter and antimatter. Violation of this CP symmetry was first observed in 1964(1), and CP violation in the weak interactions of quarks was soon established(2). Sakharov proposed(3) that CP violation is necessary to explain the observed imbalance of matter and antimatter abundance in the Universe. However, CP violation in quarks is too small to support this explanation. So far, CP violation has not been observed in non-quark elementary particle systems. It has been shown that CP violation in leptons could generate the matter-antimatter disparity through a process called leptogenesis(4). Leptonic mixing, which appears in the standard model'  s charged current interactions(5,6), provides a potential source of CP violation through a complex phase dCP, which is required by some theoretical models of leptogenesis(7-9). This CP violation can be measured in muon neutrino to electron neutrino oscillations and the corresponding antineutrino oscillations, which are experimentally accessible using accelerator-produced beams as established by the Tokai-to-Kamioka (T2K) and NOvA experiments(10,11). Until now, the value of dCP has not been substantially constrained by neutrino oscillation experiments. Here we report a measurement using long-baseline neutrino and antineutrino oscillations observed by the T2K experiment that shows a large increase in the neutrino oscillation probability, excluding values of dCP that result in a large increase in the observed antineutrino oscillation probability at three standard deviations (3 sigma). The 3 sigma confidence interval for delta(CP), which is cyclic and repeats every 2p, is [-3.41, -0.03] for the so-called normal mass ordering and [-2.54, -0.32] for the inverted mass ordering. Our results indicate CP violation in leptons and our method enables sensitive searches for matter-antimatter asymmetry in neutrino oscillations using accelerator-produced neutrino beams. Future measurements with larger datasets will test whether leptonic CP violation is larger than the CP violation in quarks.


  
Responses of soil moisture to regional climate change over the Three Rivers Source Region on the Tibetan Plateau 期刊论文
INTERNATIONAL JOURNAL OF CLIMATOLOGY, 2019
作者:  Deng, Mingshan;  Meng, Xianhong;  Li, Zhaoguo;  Lyv, Yaqiong;  Lei, Huajin;  Zhao, Lin;  Zhao, Shengnan;  Ge, Jun;  Jing, Hui
收藏  |  浏览/下载:21/0  |  提交时间:2019/11/27
land surface model data  precipitation  reanalysis data  soil moisture  temperature  Three Rivers Source region  
Predictive ability of climate change with the automated statistical downscaling method in a freeze-thaw agricultural area 期刊论文
CLIMATE DYNAMICS, 2019, 52 (11) : 7013-7028
作者:  Ouyang, Wei;  Hao, Fanghua;  Shi, Yandan;  Gao, Xiang;  Gu, Xiang;  Lian, Zhongmin
收藏  |  浏览/下载:19/0  |  提交时间:2019/11/26
Global warming  Automated statistical downscaling method (ASD model)  Non-point source pollution  Prediction ability  Freeze-thaw agricultural area  
Intraslab Deformation in the 30 November 2018 Anchorage, Alaska, M-W 7.1 Earthquake 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2019, 46 (5) : 2449-2457
作者:  Liu, Chengli;  Lay, Thorne;  Xie, Zujun;  Xiong, Xiong
收藏  |  浏览/下载:20/0  |  提交时间:2019/11/26
2018 Anchorage earthquake  intraslab rupture  Alaska subduction zone  source model  seismic inversion  seismic hazard  
Source Contributions to Carbon Monoxide Concentrations During KORUS-AQ Based on CAM-chem Model Applications 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2019, 124 (5) : 2796-2822
作者:  Tang, Wenfu;  Emmons, Louisa K.;  Arellano, Avelino F., Jr.;  Gaubert, Benjamin;  Knote, Christoph;  Tilmes, Simone;  Buchholz, Rebecca R.;  Pfister, Gabriele G.;  Diskin, Glenn S.;  Blake, Donald R.;  Blake, Nicola J.;  Meinardi, Simone;  DiGangi, Joshua P.;  Choi, Yonghoon;  Woo, Jung-Hun;  He, Cenlin;  Schroeder, Jason R.;  Suh, Inseon;  Lee, Hyo-Jung;  Jo, Hyun-Young;  Kanaya, Yugo;  Jung, Jinsang;  Lee, Youngjae;  Kim, Danbi
收藏  |  浏览/下载:30/0  |  提交时间:2019/11/26
KORUS-AQ  source contribution  carbon monoxide  CAM-chem  emissions  model evaluation  
Seasonality of the Transpiration Fraction and Its Controls Across Typical Ecosystems Within the Heihe River Basin 期刊论文
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 2019, 124 (3) : 1277-1291
作者:  Tong, Yaqin;  Wang, Pei;  Li, Xiao-Yan;  Wang, Lixin;  Wu, Xiuchen;  Shi, Fangzhong;  Bai, Yan;  Li, Engui;  Wang, Jiaqi;  Wang, Yang
收藏  |  浏览/下载:21/0  |  提交时间:2019/04/09
transpiration fraction  two-source model  Arid Inland Heihe River Basin  seasonality  sensitivity analysis  typical ecosystems