Rates of deforestation in the Amazon region have been accelerating, but the quantity and timing of nutrient losses from forested and deforested ecosystems are poorly understood. This paper investigates the broad variation in soil properties of the Amazon Basin as they influence transfers of plant nutrients from the terrestrial biosphere to the atmosphere and the aquatic biosphere. The dominant ...

The major portion of the global nitrogen cycle occurs between vegetation and soil, only minor exchanges generally taking place with the atmosphere and the hydrosphere. Nitrogen conversions in soil are briefly reviewed and a global flow chart for soil nitrogen is presented. The turnover times of nitrogen in various components of this global system are compared with its turnover times in some sel...

The oxygen isotope composition of terrestrial sulfate is affected measurably by many Earth-surface processes. During the Neoproterozoic, severe "snowball" glaciations would have had an extreme impact on the biosphere and the atmosphere. Here, we report that sulfate extracted from carbonate lenses within a Neoproterozoic glacial diamictite suite from Svalbard, with an age of approximately 635 mi...

The Genesis Discovery mission returned solar matter in the form of the solar wind with the goal of obtaining precise solar isotopic abundances (for the first time) and greatly improved elemental abundances. Measurements of the light noble gases in regime samples demonstrate that isotopes are fractionated in the solar wind relative to the solar photosphere. Theory is required for correction. Mea...

[1] We present a method for deriving constraints on the structure and composition of the lunar atmosphere by using pickup ion measurements from ARTEMIS, mapping observed fluxes from the spacecraft location to derive production rates at the source region, and fitting to a parameterized neutral atmosphere model. We apply this technique to ~12min of high-resolution burst data collected by ARTEMIS ...

[1] The geographical distribution of water-equivalenthydrogen (WEH) near the equator of Mars was compared with the topography and distribution of atmospheric water vapor to constrain possible recharge mechanisms of nearsurface water (<1 m of the surface). Recharge through a subsurface conduit provided by an aquifer, although possible, seems less likely than recharge through the atmosphere. Alth...

The job of observational meteorology is to produce knowledge of the condition of the atmosphere at a desired future time. This problem has not been solved for the scientific weather forecaster in even the most felicitous circumstances. Two gaps are especially noticeable. Firstly, the only weather stations reporting daily are on the land. On the sea, which constitutes four fifths of the earth’s ...

Despite decades of efforts aimed at unraveling its origin, the terrestrial atmosphere is still considered to be one of the most puzzling enigmas in earth sciences. Remote observations will provide information on the atmospheres of extra-solar planets, some of these may prove to be hospitable for life. Understanding the origin of Earth’s atmosphere thus improves our knowledge of the sources and ...

We present an estimate of net CO(2) exchange between the terrestrial biosphere and the atmosphere across North America for every week in the period 2000 through 2005. This estimate is derived from a set of 28,000 CO(2) mole fraction observations in the global atmosphere that are fed into a state-of-the-art data assimilation system for CO(2) called CarbonTracker. By design, the surface fluxes pr...