CO2 levels over Asia. Computer simulation showing how carbon dioxide (CO2) travels around the globe in the Earth's atmosphere, showing the results for one month (February 2006). Plumes of carbon dioxide in the simulation swirl and shift as winds disperse the greenhouse gas away from its source. The concentration of carbon dioxide is colour-coded in parts per million by volume (ppmv) from relatively low levels (green, 380ppmv) through yellow (383ppmv) to relatively high concentrations (red, 385ppmv). The regular pulsing (green) is the daily production of CO2 by plants. High concentrations (red) can be due to natural fires and human use of fossil fuels, with high levels seen here in China and Japan. For similar clips, see K004/5257 (North America) and K004/5259 (Africa). This visualisation is a 'Nature Run', a type of simulation that uses real data on atmospheric conditions and the emission of greenhouse gases. The simulation was produced by a computer model called GEOS-5 (Goddard Earth Observing System Model, Version 5), created at NASA Goddard Space Flight Center's Global Modeling and Assimilation Office. This is the highest-resolution simulation produced to date, with the results made available in 2014.