Part 2—Select Animations from the Collection
Step 1 – Examine the Range of Data Available in Earth Observatory's Global Maps
- On the Earth Observatory Home (more info) page, click the Global Maps tab that appears just below the page banner.
- Click the name of an interesting map to see a sample of the data, its color scale, and an explanation of what it shows. Click your browser's Back button to return to the Global Maps collection.
- The legend below the map indicates the months and years for which each type of data are available. Take a minute to understand how the legend indicates what data are available.
- Look specifically at the Aerosol Optical Depth image. For what dates are these data available? Aerosol Index data is available from early January 2005 through present.
- Check your understanding.
- For which months and years are 1 km2 fire data available? March 2000 through present.
- Which type of data has the longest continuous record available? Total Rainfall has the longest record.
Step 2 – Conduct your Preliminary Investigation of Carbon Pathways
- Build several animations comparing various datasets to help you visualize carbon's movements between land plants and the atmosphere. Use the step forward and step backward buttons to control the animation so you can examine the difference in the datasets from month to month.
- List each animation that you build and describe the movement of carbon that it illustrates (i.e., carbon moving from the atmosphere to the biosphere).
- What patterns can you detect in the animations? For instance, is there a relationship between the locations of vegetation and fire? Between rainfall and vegetation?
In an animation comparing these two datasets, notice how both rainfall and vegetation move to the north and then the south as seasons change through a year. This indicates that plant growth is related to rainfall, as one would expect. How does this relate to carbon movement though? Plant growth indicates that carbon dioxide is moving from the atmosphere into plant tissues. So, generally, where rain falls, carbon moves from the atmosphere to the biosphere.
Vegetation vs. Fire
Fire is a natural part of Earth's environment. Humans use fire as a tool to clear croplands or forestlands. In an animation comparing vegetation and fire, burning usually occurs in regions where the green values are low. Generally, this is because the seasonal rains have moved elsewhere, leaving the landscape dry and relatively easy for humans to burn. At high latitudes—like the boreal forests of Canada, Alaska, and Siberia—many fires occur during the summer and early fall, even while the landscape is quite green. Many of these fires are sparked by lightning strikes. The fire animation illustrates places where carbon is being released from plant tissue (the biosphere) into the atmosphere.
Image Source: NASA NEO
Step 3 – Look for Other Carbon Pathways
What datasets in the Global maps collection might provide evidence of other carbon pathways? Examine several data descriptions to find other datasets that illustrate carbon's movement through the Earth system. List your ideas of carbon "sources" and "sinks" and pathways on a piece of paper.
- In addition to plants on land, microscopic organisms, known as plankton, in the ocean also use carbon for photosynthesis. The animals form shells made of calcium carbonate or calcite (CaCO3). To observe the concentration of these microscopic plants and animals, scientists look for high concentrations of chlorophyll.
- Human respiration exchanges oxygen in the atmosphere for carbon dioxide.
- Machines that humans use release carbon from fossil fuels into the atmosphere, as do human-caused fires used for cooking.
Examine datasets related to these processes to look for evidence of carbon pathways.