"NOAA encourages science that adds benefit to society and the environment. CarbonTracker does both." said retired Navy Vice Admiral Conrad Lautenbacher, Ph.D., former undersecretary of commerce for oceans and atmosphere and NOAA administrator. CarbonTracker is a system to keep track of carbon dioxide uptake and release at the Earth's surface over time. It was developed by the Carbon Cycle Greenhouse Gases group at NOAA's Earth System Research Laboratory. As a scientific tool, CarbonTracker has helped improve the understanding of carbon uptake and release from the land and oceans, and how those sources and sinks are responding to the changing climate, increasing levels of atmospheric CO2 (the CO2 fertilization effect), and human management of land and oceans. CarbonTracker relies on the long-term monitoring of atmospheric CO2 performed by the NOAA Global Monitoring Division and international partners.
This data set shows the distribution of carbon dioxide in the "free troposphere", which is the lower atmosphere below the tropopause, but above the surface-dominated planetary boundary layer. CO2 distributions are displayed for every day from 2000 through March 11th, 2016. The large variations in CO2 seen here are caused by surface sources and sinks of CO2, coupled with transport of CO2 plumes by weather systems. The resulting patterns seen here are called "carbon weather".
The data set also shows white dots at every location and time that NOAA ESRL and collaborators collect samples of air to analyze the contents for CO2 and multiple other gases. These are the locations for which we know the mixing ratios of CO2 exactly. The rest of the globe is filled in by a computer model driven by our best knowledge of the surface sources and sinks (fossil fuel and biomass burning emissions, land biosphere and ocean uptake or release) of CO2 that are across the globe.
Plumes of CO2 can be seen moving across the globe, illustrating the importance of monitoring CO2 globally, not just locally. The large variations in CO2 concentration from season to season are due to the annual cycle of summertime green-up and autumn decay of land plants. During the winter season, plants and trees respire CO2 as they shed leaves and stop growing or decay, adding significant amounts of CO2 to the atmosphere. This process reverses during spring and summer, when plants have access to sufficient sunlight and grow leaves and flowers, or increase their size substantially and remove CO2 from the atmosphere. The summer green-up is quite visible in the movie: in July the northern hemisphere shows intense blue colors, especially over the mid-latitude regions where forests and crops take up CO2 vigorously. The large change in CO2 between the seasons caused by plant activity is sometimes referred to as the 'breathing' of the planet. In the tropics, intense red areas are visible especially during July, August and September. This is due to the burning of biomass. Some of this is natural, such as dry grasses on the savannas burning, but most of it is man-made as people burn fields to prepare them for another year of production, or burn forests to make way for new agricultural lands.
In this dataset, the color bar has a sliding scale. This means that the colors represent different CO2 values over time. For example, in the year 2000, the average global CO2 concentration was nearly 367 ppm, which shows up as light blue. As the global average increases in the visualization through March 2016, the color light blue changes value to depict 400 ppm, the global average at the end of 2014. The sliding scale dataset is best used to show the CO2 being moved around the Earth by weather patterns. This is different from CarbonTracker 2000 - 2016 Fixed Scale, which has a colorbar with a larger difference in values, a visualization that changes color more drastically, and is best used to show the overall growth in atmospheric CO2 concentration over time.
Both datasets show small white dots that depict the observation sites where glass flask atmospheric samples are taken worldwide. The observation dots are a layer that can be toggled on or off using the layers tab.