Atmospheric Chemistry and Global Change

Atmospheric methane and global change

Methane (CH4) is the most abundant organic trace gas in the atmosphere. In the distant past, variations in natural sources of methane were responsible for trends in atmospheric methane levels recorded in ice cores. Since the 1700s, rapidly growing human activities, particularly in the areas of agriculture, fossil fuel use, and waste disposal, have more than doubled methane emissions. Atmospheri...

Global atmospheric change and human health.

Toxic nitric oxide (NO) levels can regulate gene expression. Using a novel protein/DNA array, we show that toxic NO levels regulate the binding of trans-factors to various cis-elements in neuroblastoma cells, including CRE and those recognized by the transcription factors AP1, AP2, Brn-3a, EGR, E2F1 and SP1. Functionality of some of the ciselements was confirmed by electro mobility shift and re...

Ozone, Climate, and Global Atmospheric Change

Coupling advection and chemistry in a global atmospheric test model

In this talk we consider the numerical difficulties that arise when horizontal advection is coupled with chemistry on a sphere, using operator splitting. From a numerical point of view, these two processes are the most difficult parts of an atmospheric model for global studies. The advection process is solved on a uniform grid and on a so-called reduced grid, where less cells are used near the ...

Coupling of nitrous oxide and methane by global atmospheric chemistry.

Nitrous oxide (N(2)O) and methane (CH(4)) are chemically reactive greenhouse gases with well-documented atmospheric concentration increases that are attributable to anthropogenic activities. We quantified the link between N(2)O and CH(4) emissions through the coupled chemistries of the stratosphere and troposphere. Specifically, we simulated the coupled perturbations of increased N(2)O abundanc...