The electric current approach in the solar–terrestrial relationship Annales Geophysicae DOI 10.5194/angeo-35-965-2017 21 August 2017 The sequence of phenomena consisting of solar flares, coronal mass ejections (CMEs), auroral substorm, and geomagnetic storms is mostly a manifestation of electromagnetic energy dissipation. Thus, first of all, it is natural to consider each of them in terms of a sequence of power supply (dynamo), power transmission (electric currents/circuits), and dissipation (mostly observed phenomena), i.e., as an input–output process and the electric current line approach. Read more
Simultaneous measurements of new particle formation at 1 s time resolution at a street site and a rooftop site Atmospheric Chemistry and Physics DOI 10.5194/acp-17-9469-2017 8 August 2017 This study reports the distinct effects of street canyons on new particle formation (NPF) under warm or cold ambient temperature conditions because of on-road vehicle emissions; i.e., stronger condensation sinks are responsible for the reduced NPF in the springtime, but efficient nucleation and partitioning of gaseous species contribute to the enhanced NPF in the wintertime. The oxidization of biogenic organics is suggested to play an important role in growing new particles. Read more
Has dyke development in the Vietnamese Mekong Delta shifted flood hazard downstream? Hydrology and Earth System Sciences DOI 10.5194/hess-21-3991-2017 7 August 2017 In this study we provide a numerical quantification of changes in flood hazard in the Vietnamese Mekong Delta as a result of dyke development. Other important drivers to the alteration of delta flood hazard are also investigated, e.g. tidal level. The findings of our study are substantial valuable for the decision makers in Vietnam to develop holistic and harmonized floods and flood-related issues management plan for the whole delta. Read more
NOx emission trends over Chinese cities estimated from OMI observations during 2005 to 2015 Atmospheric Chemistry and Physics DOI 10.5194/acp-17-9261-2017 1 August 2017 We assess NOx emission trends over Chinese cities based on satellite NO2 observations using a method independent of chemical transport models. NOx emissions over 48 Chinese cities have decreased significantly since 2011. Cities with different dominant emission sources (i.e. power, industrial, and transportation sectors) showed variable emission decline timelines that corresponded to the schedules for emission control in different sectors. OMI observations during 2005 to 2015">Read more
An intercomparison of approaches for improving operational seasonal streamflow forecasts Hydrology and Earth System Sciences DOI 10.5194/hess-21-3915-2017 31 July 2017 Water supply forecasts are critical to support water resources operations and planning. The skill of such forecasts depends on our knowledge of (i) future meteorological conditions and (ii) the amount of water stored in a basin. We address this problem by testing several approaches that make use of these sources of predictability, either separately or in a combined fashion. The main goal is to understand the marginal benefits of both information and methodological complexity in forecast skill. Read more
Every apple has a voice: using stable isotopes to teach about food sourcing and the water cycle Hydrology and Earth System Sciences DOI 10.5194/hess-21-3799-2017 25 July 2017 Fruits take up soil water as they grow, and thus the fruit water is related to the rain or irrigation the crop receives. We used a novel sampling system to measure the stable isotopes of H and O in the fruit water to determine its geographic origin by comparing it to maps of isotopes in rain. We used this approach to teach an audience of science students and teachers about water cycle concepts and how humans may modify the water cycle through agriculture and irrigation water diversions. Read more
The double high tide at Port Ellen: Doodson’s criterion revisited Ocean Science DOI 10.5194/os-13-599-2017 20 July 2017 Some places experience double high tides, where the tide starts to ebb for a short while, only to briefly flood again before finally receding. The result is a very long high tide with weak currents, and is important for navigational purposes. The existing theory for when and where double high tides occur does not always capture them, and it can only be applied to double highs occurring on a twice-daily tide. Here, the criterion has been generalized to capture all double high or low tides. Read more
Reviews and syntheses: Systematic Earth observations for use in terrestrial carbon cycle data assimilation systems Biogeosciences DOI 10.5194/bg-14-3401-2017 19 July 2017 This paper briefly reviews data assimilation techniques in carbon cycle data assimilation and the requirements of data assimilation systems on observations. We provide a non-exhaustive overview of current observations and their uncertainties for use in terrestrial carbon cycle data assimilation, focussing on relevant space-based observations. Read more
The CarbonTracker Data Assimilation Shell (CTDAS) v1.0: implementation and global carbon balance 2001–2015 Geoscientific Model Development DOI 10.5194/gmd-10-2785-2017 18 July 2017 The CarbonTracker Data Assimilation Shell (CTDAS) is the new modular implementation of the CarbonTracker Europe (CTE) data assimilation system. We present and document CTDAS and demonstrate its ability to estimate global carbon sources and sinks. We present the latest CTE results including the distribution of the carbon sinks over the hemispheres and between the land biosphere and the oceans. We show the versatility of CTDAS with an overview of the wide range of other applications. CTDAS) v1.0: implementation and global carbon balance 2001–2015">Read more
Periodic input of dust over the Eastern Carpathians during the Holocene linked with Saharan desertification and human impact Climate of the Past DOI 10.5194/cp-13-897-2017 18 July 2017 We present the first record of dust input into an eastern European bog over the past 10 800 years. We find significant changes in past dust deposition, with large inputs related to both natural and human influences. We show evidence that Saharan desertification has had a significant impact on dust deposition in eastern Europe for the past 6100 years. Read more