We present a new data set of annual historical (1750–2014) anthropogenic chemically reactive gases (CO, CH₄, NH₃, NO_x, SO₂, NMVOCs), carbonaceous aerosols (black carbon – BC, and organic carbon – OC), and CO₂ developed with the Community Emissions Data System (CEDS). We improve upon existing inventories with a more consistent and reproducible methodology applied to all emission species, updated emission factors, and recent estimates through 2014. The data system relies on existing energy consumption data sets and regional and country-specific inventories to produce trends over recent decades. All emission species are consistently estimated using the same activity data over all time periods. Emissions are provided on an annual basis at the level of country and sector and gridded with monthly seasonality. These estimates are comparable to, but generally slightly higher than, existing global inventories. Emissions over the most recent years are more uncertain, particularly in low- and middle-income regions where country-specific emission inventories are less available. Future work will involve refining and updating these emission estimates, estimating emissions' uncertainty, and publication of the system as open-source software.

We present a new data set of annual historical (1750–2014) anthropogenic chemically reactive gases (CO, CH₄, NH₃, NO_X, SO₂, NMVOC), carbonaceous aerosols (BC and OC), and CO₂ developed with the Community Emissions Database System (CEDS). We improve upon existing inventories with a more consistent and reproducible methodology applied to all emissions species, updated emission factors, and recent estimates through 2014. The data system relies on existing energy consumption data sets and regional and country-specific inventories to produce trends over recent decades. All emissions species are consistently estimated using the same activity data over all time periods. Emissions are provided on an annual basis at the level of country and sector and gridded with monthly seasonality. These estimates are comparable to, but generally slightly higher than, existing global inventories. Emissions over the most recent years are more uncertain, particularly in low- and middle-income regions where country-specific emission inventories are less available. Future work will involve refining and updating these emission estimates, estimating emissions uncertainty, and publication of the system as open source software.

US natural gas production increased by ∼43% between 2005 and 2015, but there is disagreement among existing studies on whether this growth led to increased methane emissions. We evaluate the likely contributions of atmospheric transport to an upward trend in atmospheric methane enhancements during 2007–2015, defined as the contribution of North American emissions to atmospheric observations across the US. We find that interannual variability (IAV) in transport yields an apparent upward trend in enhancements across much of the US during this time and can explain disagreements among existing studies over emissions trends. We further find that enhancements at satellite and in situ monitoring sites are 19% higher during El Niño than La Niña, possibly because air masses spend more time over North America on average during some years. The results show that accurate modeling of IAV in transport is a key prerequisite to quantifying emissions trends.

This project discussed the technical feasibility and comprehensive utilization of resources and energy on Mars, which may have applications in the Mars exploration. Renewable fuel cell system could convert solar energy into chemical energy, electric energy and heat energy with the medium of recycled water, hydrogen and oxygen. In this project, a renewable energy system was designed based on fuel cell and water electrolyzer. Thereafter, the performance of the regenerative fuel cell was tested. The result shows that the power generation efficiency of the regenerative fuel cell was 65.41%, and the electrolysis efficiency was 90.2%. Meanwhile, the purity of hydrogen and oxygen were over 99.99% and the conductivity of water was lower than 5.0μS/cm.