The simultaneous increase of atmospheric CO(2) and nitrogen (N) deposition to terrestrial ecosystems is predicted to alter plant productivity and, consequently, to change the amount and quality of above- and belowground carbon entering forest soils. It is not known how such changes will impact the composition and function of soil fungal communities that play a key role in degrading complex carb...

We performed an intensive comparison of an isotope-incorporated atmospheric general circulation model with vapor isotopologue ratio observation data by two quasi global satellite sensors in preparation for data assimilation of water isotope ratios. A global IsoGSM simulation nudged toward the reanalysis wind field, atmospheric total column data from SCIAMACHY on Envisat, and mid-tropospheric (8...

A large-eddy simulation model developed at the National Center for Atmospheric Research (NCAR) is extended to simulate the transport and diffusion of C18OO, H2O and CO2 in the atmospheric boundary layer (ABL). The simulation results show that the 18O compositions of leaf water and the ABL CO2 are moderately sensitive to wind speed. The variations in the 18O composition of water vapour are an or...

Secondary organic aerosol (SOA) accounts for a significant fraction of ambient tropospheric aerosol and a detailed knowledge of the formation, properties and transformation of SOA is therefore required to evaluate its impact on atmospheric processes, climate and human health. The chemical and physical processes associated with SOA formation are complex and varied, and, despite considerable prog...

We present a framework for interpreting the carbon isotopic composition of sedimentary rocks, which in turn requires a fundamental reinterpretation of the carbon cycle and redox budgets over Earth's history. We propose that authigenic carbonate, produced in sediment pore fluids during early diagenesis, has played a major role in the carbon cycle in the past. This sink constitutes a minor compon...

The IceCube detector allows for the first time a measurement of atmospheric muon and neutrino energy spectra from tens of GeV up to the PeV range. The lepton flux in the highest energy region depends on both the primary cosmic ray composition around the “knee” and the contribution from prompt decays of mostly charmed hadrons produced in air showers. It is demonstrated here that a direct measure...

Liquid particle composition and heterogeneous reactions in a mountain wave Polar Stratospheric Cloud D. Lowe, A. R. MacKenzie, H. Schlager, C. Voigt, A. Dörnbrack, M. J. Mahoney, and F. Cairo Environmental Science Dept., Lancaster University, Lancaster, UK Institute for Atmospheric Physics, DLR, Oberpfaffenhofen, Germany Jet Propulsion Laboratory, California Institute of Technology, Pasadena, C...

A Mie backscattering model for spherical particles with off-center inclusion has been developed and tested. The program is capable of dealing with size parameter values up to approximately 1000, thus allowing one to simulate the optical behavior of a large variety of atmospheric aerosols, as well as cloud and precipitation particles. On the basis of this model, we simulated the optical properti...

Mass analysis is demonstrated for the detection of sub-microgram quantities of explosive samples on a metallic surface at atmospheric pressure using laser electrospray mass spectrometry (LEMS). A non-resonant femtosecond duration laser pulse vaporizes native samples for subsequent electrospray ionization and transfer into a time-of-flight mass spectrometer. LEMS was used to detect 2,3-dimethyl-...

Change in global aerosol composition since preindustrial times K. Tsigaridis, M. Krol, F. J. Dentener, Y. Balkanski, J. Lathière, S. Metzger, D. A. Hauglustaine, and M. Kanakidou Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete, P.O. Box 2208, 71003 Voutes, Heraklion, Greece Institute for Marine and Atmospheric Research, Utrecht, The Netherlands JRC, Ins...